TAP driver cleanup #1
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pull request for tap driver is now open #7 . |
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merged. |
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Functions rtsx_usb_ep0_read_register() and rtsx_usb_get_card_status() both use arbitrary buffer addresses from arguments directly for DMA and the buffers could be located in stack. This was caught by DMA-API debug check. Fixes this by using double-buffers via kzalloc in both functions to guarantee the validity of DMA buffer. WARNING: CPU: 1 PID: 25 at lib/dma-debug.c:1166 check_for_stack+0x96/0xe0() ehci-pci 0000:00:1a.0: DMA-API: device driver maps memory from stack [addr=ffff8801199e3cef] Modules linked in: rtsx_usb_ms arc4 memstick intel_rapl iosf_mbi rtl8192ce snd_hda_codec_hdmi snd_hda_codec_realtek snd_hda_codec_generic snd_hda_intel rtl_pci rtl8192c_common snd_hda_controller x86_pkg_temp_thermal snd_hda_codec rtlwifi mac80211 coretemp kvm_intel kvm iTCO_wdt snd_hwdep snd_seq snd_seq_device crct10dif_pclmul iTCO_vendor_support sparse_keymap cfg80211 crc32_pclmul snd_pcm crc32c_intel ghash_clmulni_intel rfkill i2c_i801 snd_timer shpchp snd serio_raw mei_me lpc_ich soundcore mei tpm_tis tpm wmi nfsd auth_rpcgss nfs_acl lockd grace sunrpc i915 rtsx_usb_sdmmc mmc_core 8021q uas garp stp i2c_algo_bit llc mrp drm_kms_helper usb_storage drm rtsx_usb mfd_core r8169 mii video CPU: 1 PID: 25 Comm: kworker/1:2 Not tainted 3.20.0-0.rc0.git7.3.fc22.x86_64 #1 Hardware name: WB WB-B06211/WB-B0621, BIOS EB062IWB V1.0 12/12/2013 Workqueue: events rtsx_usb_ms_handle_req [rtsx_usb_ms] 0000000000000000 000000003d188e66 ffff8801199e3808 ffffffff8187642b 0000000000000000 ffff8801199e3860 ffff8801199e3848 ffffffff810ab39a ffff8801199e3864 ffff8801199e3cef ffff880119b57098 ffff880119b37320 Call Trace: [<ffffffff8187642b>] dump_stack+0x4c/0x65 [<ffffffff810ab39a>] warn_slowpath_common+0x8a/0xc0 [<ffffffff810ab425>] warn_slowpath_fmt+0x55/0x70 [<ffffffff8187efe6>] ? _raw_spin_unlock_irqrestore+0x36/0x70 [<ffffffff81453156>] check_for_stack+0x96/0xe0 [<ffffffff81453934>] debug_dma_map_page+0x104/0x150 [<ffffffff81613b86>] usb_hcd_map_urb_for_dma+0x646/0x790 [<ffffffff81614165>] usb_hcd_submit_urb+0x1d5/0xa90 [<ffffffff81106f8f>] ? mark_held_locks+0x7f/0xc0 [<ffffffff81106f8f>] ? mark_held_locks+0x7f/0xc0 [<ffffffff81103a15>] ? lockdep_init_map+0x65/0x5d0 [<ffffffff81615d7e>] usb_submit_urb+0x42e/0x5f0 [<ffffffff81616787>] usb_start_wait_urb+0x77/0x190 [<ffffffff8124f035>] ? __kmalloc+0x205/0x2d0 [<ffffffff8161697c>] usb_control_msg+0xdc/0x130 [<ffffffffa0031669>] rtsx_usb_ep0_read_register+0x59/0x70 [rtsx_usb] [<ffffffffa00310c1>] ? rtsx_usb_get_rsp+0x41/0x50 [rtsx_usb] [<ffffffffa071da4e>] rtsx_usb_ms_handle_req+0x7ce/0x9c5 [rtsx_usb_ms] Reported-by: Josh Boyer <jwboyer@fedoraproject.org> Signed-off-by: Roger Tseng <rogerable@realtek.com> Signed-off-by: Lee Jones <lee.jones@linaro.org>
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SAS controller has its own tag allocation, which doesn't directly match to ATA tag, so SAS and SATA have different code path for ata tags. Originally we use port->scsi_host (98bd4be) to destinguish SAS controller, but libsas set ->scsi_host too, so we can't use it for the destinguish, we add a new flag for this purpose. Without this patch, the following oops can happen because scsi-mq uses a host-wide tag map shared among all devices with some integer tag values >= ATA_MAX_QUEUE. These unexpectedly high tag values cause __ata_qc_from_tag() to return NULL, which is then dereferenced in ata_qc_new_init(). BUG: unable to handle kernel NULL pointer dereference at 0000000000000058 IP: [<ffffffff804fd46e>] ata_qc_new_init+0x3e/0x120 PGD 32adf0067 PUD 32adf1067 PMD 0 Oops: 0002 [#1] SMP DEBUG_PAGEALLOC Modules linked in: iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi igb i2c_algo_bit ptp pps_core pm80xx libsas scsi_transport_sas sg coretemp eeprom w83795 i2c_i801 CPU: 4 PID: 1450 Comm: cydiskbench Not tainted 4.0.0-rc3 #1 Hardware name: Supermicro X8DTH-i/6/iF/6F/X8DTH, BIOS 2.1b 05/04/12 task: ffff8800ba86d500 ti: ffff88032a064000 task.ti: ffff88032a064000 RIP: 0010:[<ffffffff804fd46e>] [<ffffffff804fd46e>] ata_qc_new_init+0x3e/0x120 RSP: 0018:ffff88032a067858 EFLAGS: 00010046 RAX: 0000000000000000 RBX: ffff8800ba0d2230 RCX: 000000000000002a RDX: ffffffff80505ae0 RSI: 0000000000000020 RDI: ffff8800ba0d2230 RBP: ffff88032a067868 R08: 0000000000000201 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000000 R12: ffff8800ba0d0000 R13: ffff8800ba0d2230 R14: ffffffff80505ae0 R15: ffff8800ba0d0000 FS: 0000000041223950(0063) GS:ffff88033e480000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b CR2: 0000000000000058 CR3: 000000032a0a3000 CR4: 00000000000006e0 Stack: ffff880329eee758 ffff880329eee758 ffff88032a0678a8 ffffffff80502dad ffff8800ba167978 ffff880329eee758 ffff88032bf9c520 ffff8800ba167978 ffff88032bf9c520 ffff88032bf9a290 ffff88032a0678b8 ffffffff80506909 Call Trace: [<ffffffff80502dad>] ata_scsi_translate+0x3d/0x1b0 [<ffffffff80506909>] ata_sas_queuecmd+0x149/0x2a0 [<ffffffffa0046650>] sas_queuecommand+0xa0/0x1f0 [libsas] [<ffffffff804ea544>] scsi_dispatch_cmd+0xd4/0x1a0 [<ffffffff804eb50f>] scsi_queue_rq+0x66f/0x7f0 [<ffffffff803e5098>] __blk_mq_run_hw_queue+0x208/0x3f0 [<ffffffff803e54b8>] blk_mq_run_hw_queue+0x88/0xc0 [<ffffffff803e5c74>] blk_mq_insert_request+0xc4/0x130 [<ffffffff803e0b63>] blk_execute_rq_nowait+0x73/0x160 [<ffffffffa0023fca>] sg_common_write+0x3da/0x720 [sg] [<ffffffffa0025100>] sg_new_write+0x250/0x360 [sg] [<ffffffffa0025feb>] sg_write+0x13b/0x450 [sg] [<ffffffff8032ec91>] vfs_write+0xd1/0x1b0 [<ffffffff8032ee54>] SyS_write+0x54/0xc0 [<ffffffff80689932>] system_call_fastpath+0x12/0x17 tj: updated description. Fixes: 12cb5ce ("libata: use blk taging") Reported-and-tested-by: Tony Battersby <tonyb@cybernetics.com> Signed-off-by: Shaohua Li <shli@fb.com> Signed-off-by: Tejun Heo <tj@kernel.org>
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This patch fixes a NULL pointer dereference when enabling regmap event tracing in the presence of a syscon regmap, introduced by commit bdb0066 ("mfd: syscon: Decouple syscon interface from platform devices"). That patch introduced syscon regmaps that have their dev field set to NULL. The regmap trace events expect it to point to a valid struct device and feed it to dev_name(): $ echo 1 > /sys/kernel/debug/tracing/events/regmap/enable Unable to handle kernel NULL pointer dereference at virtual address 0000002c pgd = 80004000 [0000002c] *pgd=00000000 Internal error: Oops: 17 [#1] SMP ARM Modules linked in: coda videobuf2_vmalloc CPU: 0 PID: 304 Comm: kworker/0:2 Not tainted 4.0.0-rc2+ #9197 Hardware name: Freescale i.MX6 Quad/DualLite (Device Tree) Workqueue: events_freezable thermal_zone_device_check task: 9f25a200 ti: 9f1ee000 task.ti: 9f1ee000 PC is at ftrace_raw_event_regmap_block+0x3c/0xe4 LR is at _regmap_raw_read+0x1bc/0x1cc pc : [<803636e8>] lr : [<80365f2c>] psr: 600f0093 sp : 9f1efd78 ip : 9f1efdb8 fp : 9f1efdb4 r10: 00000004 r9 : 00000001 r8 : 00000001 r7 : 00000180 r6 : 00000000 r5 : 9f00e3c0 r4 : 00000003 r3 : 00000001 r2 : 00000180 r1 : 00000000 r0 : 9f00e3c0 Flags: nZCv IRQs off FIQs on Mode SVC_32 ISA ARM Segment kernel Control: 10c5387d Table: 2d91004a DAC: 00000015 Process kworker/0:2 (pid: 304, stack limit = 0x9f1ee210) Stack: (0x9f1efd78 to 0x9f1f0000) fd60: 9f1efda4 9f1efd88 fd80: 800708c0 805f9510 80927140 800f0013 9f1fc800 9eb2f490 00000000 00000180 fda0: 808e3840 00000001 9f1efdfc 9f1efdb8 80365f2c 803636b8 805f8958 800708e0 fdc0: a00f0013 803636ac 9f16de00 00000180 80927140 9f1fc800 9f1fc800 9f1efe6c fde0: 9f1efe6c 9f732400 00000000 00000000 9f1efe1c 9f1efe00 80365f70 80365d7c fe00: 80365f3c 9f1fc800 9f1fc800 00000180 9f1efe44 9f1efe20 803656a4 80365f48 fe20: 9f1fc800 00000180 9f1efe6c 9f1efe6c 9f732400 00000000 9f1efe64 9f1efe48 fe40: 803657bc 80365634 00000001 9e95f910 9f1fc800 9f1efeb4 9f1efe8c 9f1efe68 fe60: 80452ac0 80365778 9f1efe8c 9f1efe78 9e93d400 9e93d5e8 9f1efeb4 9f72ef40 fe80: 9f1efeac 9f1efe90 8044e11c 80452998 8045298c 9e93d608 9e93d400 808e1978 fea0: 9f1efecc 9f1efeb0 8044fd14 8044e0d0 ffffffff 9f25a200 9e93d608 9e481380 fec0: 9f1efedc 9f1efed0 8044fde8 8044fcec 9f1eff1c 9f1efee0 80038d50 8044fdd8 fee0: 9f1ee020 9f72ef40 9e481398 00000000 00000008 9f72ef54 9f1ee020 9f72ef40 ff00: 9e481398 9e481380 00000008 9f72ef40 9f1eff5c 9f1eff20 80039754 80038bfc ff20: 00000000 9e481380 80894100 808e1662 00000000 9e4f2ec0 00000000 9e481380 ff40: 800396f8 00000000 00000000 00000000 9f1effac 9f1eff60 8003e020 80039704 ff60: ffffffff 00000000 ffffffff 9e481380 00000000 00000000 9f1eff78 9f1eff78 ff80: 00000000 00000000 9f1eff88 9f1eff88 9e4f2ec0 8003df30 00000000 00000000 ffa0: 00000000 9f1effb0 8000eb60 8003df3c 00000000 00000000 00000000 00000000 ffc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 ffe0: 00000000 00000000 00000000 00000000 00000013 00000000 ffffffff ffffffff Backtrace: [<803636ac>] (ftrace_raw_event_regmap_block) from [<80365f2c>] (_regmap_raw_read+0x1bc/0x1cc) r9:00000001 r8:808e3840 r7:00000180 r6:00000000 r5:9eb2f490 r4:9f1fc800 [<80365d70>] (_regmap_raw_read) from [<80365f70>] (_regmap_bus_read+0x34/0x6c) r10:00000000 r9:00000000 r8:9f732400 r7:9f1efe6c r6:9f1efe6c r5:9f1fc800 r4:9f1fc800 [<80365f3c>] (_regmap_bus_read) from [<803656a4>] (_regmap_read+0x7c/0x144) r6:00000180 r5:9f1fc800 r4:9f1fc800 r3:80365f3c [<80365628>] (_regmap_read) from [<803657bc>] (regmap_read+0x50/0x70) r9:00000000 r8:9f732400 r7:9f1efe6c r6:9f1efe6c r5:00000180 r4:9f1fc800 [<8036576c>] (regmap_read) from [<80452ac0>] (imx_get_temp+0x134/0x1a4) r6:9f1efeb4 r5:9f1fc800 r4:9e95f910 r3:00000001 [<8045298c>] (imx_get_temp) from [<8044e11c>] (thermal_zone_get_temp+0x58/0x74) r7:9f72ef40 r6:9f1efeb4 r5:9e93d5e8 r4:9e93d400 [<8044e0c4>] (thermal_zone_get_temp) from [<8044fd14>] (thermal_zone_device_update+0x34/0xec) r6:808e1978 r5:9e93d400 r4:9e93d608 r3:8045298c [<8044fce0>] (thermal_zone_device_update) from [<8044fde8>] (thermal_zone_device_check+0x1c/0x20) r5:9e481380 r4:9e93d608 [<8044fdcc>] (thermal_zone_device_check) from [<80038d50>] (process_one_work+0x160/0x3d4) [<80038bf0>] (process_one_work) from [<80039754>] (worker_thread+0x5c/0x4f4) r10:9f72ef40 r9:00000008 r8:9e481380 r7:9e481398 r6:9f72ef40 r5:9f1ee020 r4:9f72ef54 [<800396f8>] (worker_thread) from [<8003e020>] (kthread+0xf0/0x108) r10:00000000 r9:00000000 r8:00000000 r7:800396f8 r6:9e481380 r5:00000000 r4:9e4f2ec0 [<8003df30>] (kthread) from [<8000eb60>] (ret_from_fork+0x14/0x34) r7:00000000 r6:00000000 r5:8003df30 r4:9e4f2ec0 Code: e3140040 1a00001a e3140020 1a000016 (e596002c) ---[ end trace 193c15c2494ec960 ]--- Fixes: bdb0066 (mfd: syscon: Decouple syscon interface from platform devices) Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de> Signed-off-by: Mark Brown <broonie@kernel.org> Cc: stable@vger.kernel.org
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…lpcr()
Currently, kvmppc_set_lpcr() has a spinlock around the whole function,
and inside that does mutex_lock(&kvm->lock). It is not permitted to
take a mutex while holding a spinlock, because the mutex_lock might
call schedule(). In addition, this causes lockdep to warn about a
lock ordering issue:
======================================================
[ INFO: possible circular locking dependency detected ]
3.18.0-kvm-04645-gdfea862-dirty #131 Not tainted
-------------------------------------------------------
qemu-system-ppc/8179 is trying to acquire lock:
(&kvm->lock){+.+.+.}, at: [<d00000000ecc1f54>] .kvmppc_set_lpcr+0xf4/0x1c0 [kvm_hv]
but task is already holding lock:
(&(&vcore->lock)->rlock){+.+...}, at: [<d00000000ecc1ea0>] .kvmppc_set_lpcr+0x40/0x1c0 [kvm_hv]
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #1 (&(&vcore->lock)->rlock){+.+...}:
[<c000000000b3c120>] .mutex_lock_nested+0x80/0x570
[<d00000000ecc7a14>] .kvmppc_vcpu_run_hv+0xc4/0xe40 [kvm_hv]
[<d00000000eb9f5cc>] .kvmppc_vcpu_run+0x2c/0x40 [kvm]
[<d00000000eb9cb24>] .kvm_arch_vcpu_ioctl_run+0x54/0x160 [kvm]
[<d00000000eb94478>] .kvm_vcpu_ioctl+0x4a8/0x7b0 [kvm]
[<c00000000026cbb4>] .do_vfs_ioctl+0x444/0x770
[<c00000000026cfa4>] .SyS_ioctl+0xc4/0xe0
[<c000000000009264>] syscall_exit+0x0/0x98
-> #0 (&kvm->lock){+.+.+.}:
[<c0000000000ff28c>] .lock_acquire+0xcc/0x1a0
[<c000000000b3c120>] .mutex_lock_nested+0x80/0x570
[<d00000000ecc1f54>] .kvmppc_set_lpcr+0xf4/0x1c0 [kvm_hv]
[<d00000000ecc510c>] .kvmppc_set_one_reg_hv+0x4dc/0x990 [kvm_hv]
[<d00000000eb9f234>] .kvmppc_set_one_reg+0x44/0x330 [kvm]
[<d00000000eb9c9dc>] .kvm_vcpu_ioctl_set_one_reg+0x5c/0x150 [kvm]
[<d00000000eb9ced4>] .kvm_arch_vcpu_ioctl+0x214/0x2c0 [kvm]
[<d00000000eb940b0>] .kvm_vcpu_ioctl+0xe0/0x7b0 [kvm]
[<c00000000026cbb4>] .do_vfs_ioctl+0x444/0x770
[<c00000000026cfa4>] .SyS_ioctl+0xc4/0xe0
[<c000000000009264>] syscall_exit+0x0/0x98
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&(&vcore->lock)->rlock);
lock(&kvm->lock);
lock(&(&vcore->lock)->rlock);
lock(&kvm->lock);
*** DEADLOCK ***
2 locks held by qemu-system-ppc/8179:
#0: (&vcpu->mutex){+.+.+.}, at: [<d00000000eb93f18>] .vcpu_load+0x28/0x90 [kvm]
#1: (&(&vcore->lock)->rlock){+.+...}, at: [<d00000000ecc1ea0>] .kvmppc_set_lpcr+0x40/0x1c0 [kvm_hv]
stack backtrace:
CPU: 4 PID: 8179 Comm: qemu-system-ppc Not tainted 3.18.0-kvm-04645-gdfea862-dirty #131
Call Trace:
[c000001a66c0f310] [c000000000b486ac] .dump_stack+0x88/0xb4 (unreliable)
[c000001a66c0f390] [c0000000000f8bec] .print_circular_bug+0x27c/0x3d0
[c000001a66c0f440] [c0000000000fe9e8] .__lock_acquire+0x2028/0x2190
[c000001a66c0f5d0] [c0000000000ff28c] .lock_acquire+0xcc/0x1a0
[c000001a66c0f6a0] [c000000000b3c120] .mutex_lock_nested+0x80/0x570
[c000001a66c0f7c0] [d00000000ecc1f54] .kvmppc_set_lpcr+0xf4/0x1c0 [kvm_hv]
[c000001a66c0f860] [d00000000ecc510c] .kvmppc_set_one_reg_hv+0x4dc/0x990 [kvm_hv]
[c000001a66c0f8d0] [d00000000eb9f234] .kvmppc_set_one_reg+0x44/0x330 [kvm]
[c000001a66c0f960] [d00000000eb9c9dc] .kvm_vcpu_ioctl_set_one_reg+0x5c/0x150 [kvm]
[c000001a66c0f9f0] [d00000000eb9ced4] .kvm_arch_vcpu_ioctl+0x214/0x2c0 [kvm]
[c000001a66c0faf0] [d00000000eb940b0] .kvm_vcpu_ioctl+0xe0/0x7b0 [kvm]
[c000001a66c0fcb0] [c00000000026cbb4] .do_vfs_ioctl+0x444/0x770
[c000001a66c0fd90] [c00000000026cfa4] .SyS_ioctl+0xc4/0xe0
[c000001a66c0fe30] [c000000000009264] syscall_exit+0x0/0x98
This fixes it by moving the mutex_lock()/mutex_unlock() pair outside
the spin-locked region.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
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If register_shrinker() failed, nfsd will cause a NULL pointer access as, [ 9250.875465] nfsd: last server has exited, flushing export cache [ 9251.427270] BUG: unable to handle kernel NULL pointer dereference at (null) [ 9251.427393] IP: [<ffffffff8136fc29>] __list_del_entry+0x29/0xd0 [ 9251.427579] PGD 13e4d067 PUD 13e4c067 PMD 0 [ 9251.427633] Oops: 0000 [#1] SMP DEBUG_PAGEALLOC [ 9251.427706] Modules linked in: ip6t_rpfilter ip6t_REJECT bnep bluetooth xt_conntrack cfg80211 rfkill ebtable_nat ebtable_broute bridge stp llc ebtable_filter ebtables ip6table_nat nf_conntrack_ipv6 nf_defrag_ipv6 nf_nat_ipv6 ip6table_mangle ip6table_security ip6table_raw ip6table_filter ip6_tables iptable_nat nf_conntrack_ipv4 nf_defrag_ipv4 nf_nat_ipv4 nf_nat nf_conntrack iptable_mangle iptable_security iptable_raw btrfs xfs microcode ppdev serio_raw pcspkr xor libcrc32c raid6_pq e1000 parport_pc parport i2c_piix4 i2c_core nfsd(OE-) auth_rpcgss nfs_acl lockd sunrpc(E) ata_generic pata_acpi [ 9251.428240] CPU: 0 PID: 1557 Comm: rmmod Tainted: G OE 3.16.0-rc2+ #22 [ 9251.428366] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 07/31/2013 [ 9251.428496] task: ffff880000849540 ti: ffff8800136f4000 task.ti: ffff8800136f4000 [ 9251.428593] RIP: 0010:[<ffffffff8136fc29>] [<ffffffff8136fc29>] __list_del_entry+0x29/0xd0 [ 9251.428696] RSP: 0018:ffff8800136f7ea0 EFLAGS: 00010207 [ 9251.428751] RAX: 0000000000000000 RBX: ffffffffa0116d48 RCX: dead000000200200 [ 9251.428814] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffffa0116d48 [ 9251.428876] RBP: ffff8800136f7ea0 R08: ffff8800136f4000 R09: 0000000000000001 [ 9251.428939] R10: 8080808080808080 R11: 0000000000000000 R12: ffffffffa011a5a0 [ 9251.429002] R13: 0000000000000800 R14: 0000000000000000 R15: 00000000018ac090 [ 9251.429064] FS: 00007fb9acef0740(0000) GS:ffff88003fa00000(0000) knlGS:0000000000000000 [ 9251.429164] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 9251.429221] CR2: 0000000000000000 CR3: 0000000031a17000 CR4: 00000000001407f0 [ 9251.429306] Stack: [ 9251.429410] ffff8800136f7eb8 ffffffff8136fcdd ffffffffa0116d20 ffff8800136f7ed0 [ 9251.429511] ffffffff8118a0f2 0000000000000000 ffff8800136f7ee0 ffffffffa00eb765 [ 9251.429610] ffff8800136f7ef0 ffffffffa010e93c ffff8800136f7f78 ffffffff81104ac2 [ 9251.429709] Call Trace: [ 9251.429755] [<ffffffff8136fcdd>] list_del+0xd/0x30 [ 9251.429896] [<ffffffff8118a0f2>] unregister_shrinker+0x22/0x40 [ 9251.430037] [<ffffffffa00eb765>] nfsd_reply_cache_shutdown+0x15/0x90 [nfsd] [ 9251.430106] [<ffffffffa010e93c>] exit_nfsd+0x9/0x6cd [nfsd] [ 9251.430192] [<ffffffff81104ac2>] SyS_delete_module+0x162/0x200 [ 9251.430280] [<ffffffff81013b69>] ? do_notify_resume+0x59/0x90 [ 9251.430395] [<ffffffff816f2369>] system_call_fastpath+0x16/0x1b [ 9251.430457] Code: 00 00 55 48 8b 17 48 b9 00 01 10 00 00 00 ad de 48 8b 47 08 48 89 e5 48 39 ca 74 29 48 b9 00 02 20 00 00 00 ad de 48 39 c8 74 7a <4c> 8b 00 4c 39 c7 75 53 4c 8b 42 08 4c 39 c7 75 2b 48 89 42 08 [ 9251.430691] RIP [<ffffffff8136fc29>] __list_del_entry+0x29/0xd0 [ 9251.430755] RSP <ffff8800136f7ea0> [ 9251.430805] CR2: 0000000000000000 [ 9251.431033] ---[ end trace 080f3050d082b4ea ]--- Signed-off-by: Kinglong Mee <kinglongmee@gmail.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
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We occasionally see in procedure mlx4_GEN_EQE that the driver tries to grab an uninitialized mutex. This can occur in only one of two ways: 1. We are trying to generate an async event on an uninitialized slave. 2. We are trying to generate an async event on an illegal slave number ( < 0 or > persist->num_vfs) or an inactive slave. To deal with #1: move the mutex initialization from specific slave init sequence in procedure mlx_master_do_cmd to mlx4_multi_func_init() (so that the mutex is always initialized for all slaves). To deal with #2: check in procedure mlx4_GEN_EQE that the slave number provided is in the proper range and that the slave is active. Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il> Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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Qiu Xishi reported the following BUG when testing hot-add/hot-remove node under stress condition: BUG: unable to handle kernel paging request at 0000000000025f60 IP: next_online_pgdat+0x1/0x50 PGD 0 Oops: 0000 [#1] SMP ACPI: Device does not support D3cold Modules linked in: fuse nls_iso8859_1 nls_cp437 vfat fat loop dm_mod coretemp mperf crc32c_intel ghash_clmulni_intel aesni_intel ablk_helper cryptd lrw gf128mul glue_helper aes_x86_64 pcspkr microcode igb dca i2c_algo_bit ipv6 megaraid_sas iTCO_wdt i2c_i801 i2c_core iTCO_vendor_support tg3 sg hwmon ptp lpc_ich pps_core mfd_core acpi_pad rtc_cmos button ext3 jbd mbcache sd_mod crc_t10dif scsi_dh_alua scsi_dh_rdac scsi_dh_hp_sw scsi_dh_emc scsi_dh ahci libahci libata scsi_mod [last unloaded: rasf] CPU: 23 PID: 238 Comm: kworker/23:1 Tainted: G O 3.10.15-5885-euler0302 #1 Hardware name: HUAWEI TECHNOLOGIES CO.,LTD. Huawei N1/Huawei N1, BIOS V100R001 03/02/2015 Workqueue: events vmstat_update task: ffffa800d32c0000 ti: ffffa800d32ae000 task.ti: ffffa800d32ae000 RIP: 0010: next_online_pgdat+0x1/0x50 RSP: 0018:ffffa800d32afce8 EFLAGS: 00010286 RAX: 0000000000001440 RBX: ffffffff81da53b8 RCX: 0000000000000082 RDX: 0000000000000000 RSI: 0000000000000082 RDI: 0000000000000000 RBP: ffffa800d32afd28 R08: ffffffff81c93bfc R09: ffffffff81cbdc96 R10: 00000000000040ec R11: 00000000000000a0 R12: ffffa800fffb3440 R13: ffffa800d32afd38 R14: 0000000000000017 R15: ffffa800e6616800 FS: 0000000000000000(0000) GS:ffffa800e6600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000025f60 CR3: 0000000001a0b000 CR4: 00000000001407e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: refresh_cpu_vm_stats+0xd0/0x140 vmstat_update+0x11/0x50 process_one_work+0x194/0x3d0 worker_thread+0x12b/0x410 kthread+0xc6/0xd0 ret_from_fork+0x7c/0xb0 The cause is the "memset(pgdat, 0, sizeof(*pgdat))" at the end of try_offline_node, which will reset all the content of pgdat to 0, as the pgdat is accessed lock-free, so that the users still using the pgdat will panic, such as the vmstat_update routine. process A: offline node XX: vmstat_updat() refresh_cpu_vm_stats() for_each_populated_zone() find online node XX cond_resched() offline cpu and memory, then try_offline_node() node_set_offline(nid), and memset(pgdat, 0, sizeof(*pgdat)) zone = next_zone(zone) pg_data_t *pgdat = zone->zone_pgdat; // here pgdat is NULL now next_online_pgdat(pgdat) next_online_node(pgdat->node_id); // NULL pointer access So the solution here is postponing the reset of obsolete pgdat from try_offline_node() to hotadd_new_pgdat(), and just resetting pgdat->nr_zones and pgdat->classzone_idx to be 0 rather than the memset 0 to avoid breaking pointer information in pgdat. Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com> Reported-by: Xishi Qiu <qiuxishi@huawei.com> Suggested-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: David Rientjes <rientjes@google.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Taku Izumi <izumi.taku@jp.fujitsu.com> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Xie XiuQi <xiexiuqi@huawei.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Commit 3c60509 ("mm/page_alloc: restrict max order of merging on isolated pageblock") changed the logic of unset_migratetype_isolate to check the buddy allocator and explicitly call __free_pages to merge. The page that is being freed in this path never had prep_new_page called so set_page_refcounted is called explicitly but there is no call to kernel_map_pages. With the default kernel_map_pages this is mostly harmless but if kernel_map_pages does any manipulation of the page tables (unmapping or setting pages to read only) this may trigger a fault: alloc_contig_range test_pages_isolated(ceb00, ced00) failed Unable to handle kernel paging request at virtual address ffffffc0cec00000 pgd = ffffffc045fc4000 [ffffffc0cec00000] *pgd=0000000000000000 Internal error: Oops: 9600004f [#1] PREEMPT SMP Modules linked in: exfatfs CPU: 1 PID: 23237 Comm: TimedEventQueue Not tainted 3.10.49-gc72ad36-dirty #1 task: ffffffc03de52100 ti: ffffffc015388000 task.ti: ffffffc015388000 PC is at memset+0xc8/0x1c0 LR is at kernel_map_pages+0x1ec/0x244 Fix this by calling kernel_map_pages to ensure the page is set in the page table properly Fixes: 3c60509 ("mm/page_alloc: restrict max order of merging on isolated pageblock") Signed-off-by: Laura Abbott <lauraa@codeaurora.org> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Mel Gorman <mgorman@suse.de> Acked-by: Rik van Riel <riel@redhat.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Cc: Xishi Qiu <qiuxishi@huawei.com> Cc: Vladimir Davydov <vdavydov@parallels.com> Acked-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Gioh Kim <gioh.kim@lge.com> Cc: Michal Nazarewicz <mina86@mina86.com> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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[ 60.988363] ======================================================
[ 60.988754] [ INFO: possible circular locking dependency detected ]
[ 60.989152] 3.19.0+ #194 Not tainted
[ 60.989377] -------------------------------------------------------
[ 60.989781] swapper/3/0 is trying to acquire lock:
[ 60.990079] (&(&n_ptr->lock)->rlock){+.-...}, at: [<ffffffffa0006dca>] tipc_link_retransmit+0x1aa/0x240 [tipc]
[ 60.990743]
[ 60.990743] but task is already holding lock:
[ 60.991106] (&(&bclink->lock)->rlock){+.-...}, at: [<ffffffffa00004be>] tipc_bclink_lock+0x8e/0xa0 [tipc]
[ 60.991738]
[ 60.991738] which lock already depends on the new lock.
[ 60.991738]
[ 60.992174]
[ 60.992174] the existing dependency chain (in reverse order) is:
[ 60.992174]
-> #1 (&(&bclink->lock)->rlock){+.-...}:
[ 60.992174] [<ffffffff810a9c0c>] lock_acquire+0x9c/0x140
[ 60.992174] [<ffffffff8179c41f>] _raw_spin_lock_bh+0x3f/0x50
[ 60.992174] [<ffffffffa00004be>] tipc_bclink_lock+0x8e/0xa0 [tipc]
[ 60.992174] [<ffffffffa0000f57>] tipc_bclink_add_node+0x97/0xf0 [tipc]
[ 60.992174] [<ffffffffa0011815>] tipc_node_link_up+0xf5/0x110 [tipc]
[ 60.992174] [<ffffffffa0007783>] link_state_event+0x2b3/0x4f0 [tipc]
[ 60.992174] [<ffffffffa00193c0>] tipc_link_proto_rcv+0x24c/0x418 [tipc]
[ 60.992174] [<ffffffffa0008857>] tipc_rcv+0x827/0xac0 [tipc]
[ 60.992174] [<ffffffffa0002ca3>] tipc_l2_rcv_msg+0x73/0xd0 [tipc]
[ 60.992174] [<ffffffff81646e66>] __netif_receive_skb_core+0x746/0x980
[ 60.992174] [<ffffffff816470c1>] __netif_receive_skb+0x21/0x70
[ 60.992174] [<ffffffff81647295>] netif_receive_skb_internal+0x35/0x130
[ 60.992174] [<ffffffff81648218>] napi_gro_receive+0x158/0x1d0
[ 60.992174] [<ffffffff81559e05>] e1000_clean_rx_irq+0x155/0x490
[ 60.992174] [<ffffffff8155c1b7>] e1000_clean+0x267/0x990
[ 60.992174] [<ffffffff81647b60>] net_rx_action+0x150/0x360
[ 60.992174] [<ffffffff8105ec43>] __do_softirq+0x123/0x360
[ 60.992174] [<ffffffff8105f12e>] irq_exit+0x8e/0xb0
[ 60.992174] [<ffffffff8179f9f5>] do_IRQ+0x65/0x110
[ 60.992174] [<ffffffff8179da6f>] ret_from_intr+0x0/0x13
[ 60.992174] [<ffffffff8100de9f>] arch_cpu_idle+0xf/0x20
[ 60.992174] [<ffffffff8109dfa6>] cpu_startup_entry+0x2f6/0x3f0
[ 60.992174] [<ffffffff81033cda>] start_secondary+0x13a/0x150
[ 60.992174]
-> #0 (&(&n_ptr->lock)->rlock){+.-...}:
[ 60.992174] [<ffffffff810a8f7d>] __lock_acquire+0x163d/0x1ca0
[ 60.992174] [<ffffffff810a9c0c>] lock_acquire+0x9c/0x140
[ 60.992174] [<ffffffff8179c41f>] _raw_spin_lock_bh+0x3f/0x50
[ 60.992174] [<ffffffffa0006dca>] tipc_link_retransmit+0x1aa/0x240 [tipc]
[ 60.992174] [<ffffffffa0001e11>] tipc_bclink_rcv+0x611/0x640 [tipc]
[ 60.992174] [<ffffffffa0008646>] tipc_rcv+0x616/0xac0 [tipc]
[ 60.992174] [<ffffffffa0002ca3>] tipc_l2_rcv_msg+0x73/0xd0 [tipc]
[ 60.992174] [<ffffffff81646e66>] __netif_receive_skb_core+0x746/0x980
[ 60.992174] [<ffffffff816470c1>] __netif_receive_skb+0x21/0x70
[ 60.992174] [<ffffffff81647295>] netif_receive_skb_internal+0x35/0x130
[ 60.992174] [<ffffffff81648218>] napi_gro_receive+0x158/0x1d0
[ 60.992174] [<ffffffff81559e05>] e1000_clean_rx_irq+0x155/0x490
[ 60.992174] [<ffffffff8155c1b7>] e1000_clean+0x267/0x990
[ 60.992174] [<ffffffff81647b60>] net_rx_action+0x150/0x360
[ 60.992174] [<ffffffff8105ec43>] __do_softirq+0x123/0x360
[ 60.992174] [<ffffffff8105f12e>] irq_exit+0x8e/0xb0
[ 60.992174] [<ffffffff8179f9f5>] do_IRQ+0x65/0x110
[ 60.992174] [<ffffffff8179da6f>] ret_from_intr+0x0/0x13
[ 60.992174] [<ffffffff8100de9f>] arch_cpu_idle+0xf/0x20
[ 60.992174] [<ffffffff8109dfa6>] cpu_startup_entry+0x2f6/0x3f0
[ 60.992174] [<ffffffff81033cda>] start_secondary+0x13a/0x150
[ 60.992174]
[ 60.992174] other info that might help us debug this:
[ 60.992174]
[ 60.992174] Possible unsafe locking scenario:
[ 60.992174]
[ 60.992174] CPU0 CPU1
[ 60.992174] ---- ----
[ 60.992174] lock(&(&bclink->lock)->rlock);
[ 60.992174] lock(&(&n_ptr->lock)->rlock);
[ 60.992174] lock(&(&bclink->lock)->rlock);
[ 60.992174] lock(&(&n_ptr->lock)->rlock);
[ 60.992174]
[ 60.992174] *** DEADLOCK ***
[ 60.992174]
[ 60.992174] 3 locks held by swapper/3/0:
[ 60.992174] #0: (rcu_read_lock){......}, at: [<ffffffff81646791>] __netif_receive_skb_core+0x71/0x980
[ 60.992174] #1: (rcu_read_lock){......}, at: [<ffffffffa0002c35>] tipc_l2_rcv_msg+0x5/0xd0 [tipc]
[ 60.992174] #2: (&(&bclink->lock)->rlock){+.-...}, at: [<ffffffffa00004be>] tipc_bclink_lock+0x8e/0xa0 [tipc]
[ 60.992174]
The correct the sequence of grabbing n_ptr->lock and bclink->lock
should be that the former is first held and the latter is then taken,
which exactly happened on CPU1. But especially when the retransmission
of broadcast link is failed, bclink->lock is first held in
tipc_bclink_rcv(), and n_ptr->lock is taken in link_retransmit_failure()
called by tipc_link_retransmit() subsequently, which is demonstrated on
CPU0. As a result, deadlock occurs.
If the order of holding the two locks happening on CPU0 is reversed, the
deadlock risk will be relieved. Therefore, the node lock taken in
link_retransmit_failure() originally is moved to tipc_bclink_rcv()
so that it's obtained before bclink lock. But the precondition of
the adjustment of node lock is that responding to bclink reset event
must be moved from tipc_bclink_unlock() to tipc_node_unlock().
Reviewed-by: Erik Hugne <erik.hugne@ericsson.com>
Signed-off-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Ying Xue says: ==================== tipc: fix two corner issues The patch set aims at resolving the following two critical issues: Patch #1: Resolve a deadlock which happens while all links are reset Patch #2: Correct a mistake usage of RCU lock which is used to protect node list ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
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Andrew Lunn says: ==================== DSA Mavell drivers refactoring and cleanup v1->v2: * Add missing signed-of-by: For patches authored by Guenter Roeck. * Add Reviewed by from Guenter Roack to patch #5. This is a collection of patches again net-next from today containing refactoring and consolidate of code, cleanups and using #define's to replace register numbers. Patch #1 Swaps the 6131 driver to use the consolidated setup code. Patch #2 Moves the Switch IDs used during probe into a central location. We need these later so that we can differentiate the different features the devices have. Patch #3 Makes the 6131 driver set the number of ports in the private state structure. It then uses this, rather than hard coded maximum number of ports. Patch #4 Similar to Patch #3, but for the 6123_61_65 driver. Patch #5 Similar to Patch #3, and #4, but for all the remaining drivers. This greatly increases the similarity of the code between drivers, allow further patches to consolidate the duplicated code. Patch #6 Consolidate the switch reset code, which has two minor variants. Removes around 35 lines per driver. Patch #7 Moves phy page access functions out of the 6352 driver into the shared code. Currently only the 6352 driver uses this, but it is likely other devices will come along wanting this functionality. Patch #8 Consolidates the code used to access phy registers. Removes around 40 lines of code per driver. Patch #9 Fixes missing mutex locking in the EEE code, and refactors the code a bit to make it more understandable with respect to locks. Patch #10 Consolidates reading statistics. This is very similar code for all devices, but the number of available statistics differ, which can be determined from the product ID. Removes around 65 lines per driver. Patch #11 Add #defines for registers, and bits within the registers. For the moment, this is limited to the shared code. The individual drivers will be converted once the remaining duplicated code is consolidated Patch #12 Fix broken statistic counters on the 6172. The 6352 family requires the port number is poked into a different set of bits in the register compared to other devices. Many thanks to Guenter Roeck for repeatedly reviewing the patches and testing them on his hardware. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
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…_ram allocator
Recently I came across high fragmentation of vm_map_ram allocator:
vmap_block has free space, but still new blocks continue to appear.
Further investigation showed that certain mapping/unmapping sequences
can exhaust vmalloc space. On small 32bit systems that's not a big
problem, cause purging will be called soon on a first allocation failure
(alloc_vmap_area), but on 64bit machines, e.g. x86_64 has 45 bits of
vmalloc space, that can be a disaster.
1) I came up with a simple allocation sequence, which exhausts virtual
space very quickly:
while (iters) {
/* Map/unmap big chunk */
vaddr = vm_map_ram(pages, 16, -1, PAGE_KERNEL);
vm_unmap_ram(vaddr, 16);
/* Map/unmap small chunks.
*
* -1 for hole, which should be left at the end of each block
* to keep it partially used, with some free space available */
for (i = 0; i < (VMAP_BBMAP_BITS - 16) / 8 - 1; i++) {
vaddr = vm_map_ram(pages, 8, -1, PAGE_KERNEL);
vm_unmap_ram(vaddr, 8);
}
}
The idea behind is simple:
1. We have to map a big chunk, e.g. 16 pages.
2. Then we have to occupy the remaining space with smaller chunks, i.e.
8 pages. At the end small hole should remain to keep block in free list,
but do not let big chunk to occupy remaining space.
3. Goto 1 - allocation request of 16 pages can't be completed (only 8 slots
are left free in the block in the #2 step), new block will be allocated,
all further requests will lay into newly allocated block.
To have some measurement numbers for all further tests I setup ftrace and
enabled 4 basic calls in a function profile:
echo vm_map_ram > /sys/kernel/debug/tracing/set_ftrace_filter;
echo alloc_vmap_area >> /sys/kernel/debug/tracing/set_ftrace_filter;
echo vm_unmap_ram >> /sys/kernel/debug/tracing/set_ftrace_filter;
echo free_vmap_block >> /sys/kernel/debug/tracing/set_ftrace_filter;
So for this scenario I got these results:
BEFORE (all new blocks are put to the head of a free list)
# cat /sys/kernel/debug/tracing/trace_stat/function0
Function Hit Time Avg s^2
-------- --- ---- --- ---
vm_map_ram 126000 30683.30 us 0.243 us 30819.36 us
vm_unmap_ram 126000 22003.24 us 0.174 us 340.886 us
alloc_vmap_area 1000 4132.065 us 4.132 us 0.903 us
AFTER (all new blocks are put to the tail of a free list)
# cat /sys/kernel/debug/tracing/trace_stat/function0
Function Hit Time Avg s^2
-------- --- ---- --- ---
vm_map_ram 126000 28713.13 us 0.227 us 24944.70 us
vm_unmap_ram 126000 20403.96 us 0.161 us 1429.872 us
alloc_vmap_area 993 3916.795 us 3.944 us 29.370 us
free_vmap_block 992 654.157 us 0.659 us 1.273 us
SUMMARY:
The most interesting numbers in those tables are numbers of block
allocations and deallocations: alloc_vmap_area and free_vmap_block
calls, which show that before the change blocks were not freed, and
virtual space and physical memory (vmap_block structure allocations,
etc) were consumed.
Average time which were spent in vm_map_ram/vm_unmap_ram became slightly
better. That can be explained with a reasonable amount of blocks in a
free list, which we need to iterate to find a suitable free block.
2) Another scenario is a random allocation:
while (iters) {
/* Randomly take number from a range [1..32/64] */
nr = rand(1, VMAP_MAX_ALLOC);
vaddr = vm_map_ram(pages, nr, -1, PAGE_KERNEL);
vm_unmap_ram(vaddr, nr);
}
I chose mersenne twister PRNG to generate persistent random state to
guarantee that both runs have the same random sequence. For each
vm_map_ram call random number from [1..32/64] was taken to represent
amount of pages which I do map.
I did 10'000 vm_map_ram calls and got these two tables:
BEFORE (all new blocks are put to the head of a free list)
# cat /sys/kernel/debug/tracing/trace_stat/function0
Function Hit Time Avg s^2
-------- --- ---- --- ---
vm_map_ram 10000 10170.01 us 1.017 us 993.609 us
vm_unmap_ram 10000 5321.823 us 0.532 us 59.789 us
alloc_vmap_area 420 2150.239 us 5.119 us 3.307 us
free_vmap_block 37 159.587 us 4.313 us 134.344 us
AFTER (all new blocks are put to the tail of a free list)
# cat /sys/kernel/debug/tracing/trace_stat/function0
Function Hit Time Avg s^2
-------- --- ---- --- ---
vm_map_ram 10000 7745.637 us 0.774 us 395.229 us
vm_unmap_ram 10000 5460.573 us 0.546 us 67.187 us
alloc_vmap_area 414 2201.650 us 5.317 us 5.591 us
free_vmap_block 412 574.421 us 1.394 us 15.138 us
SUMMARY:
'BEFORE' table shows, that 420 blocks were allocated and only 37 were
freed. Remained 383 blocks are still in a free list, consuming virtual
space and physical memory.
'AFTER' table shows, that 414 blocks were allocated and 412 were really
freed. 2 blocks remained in a free list.
So fragmentation was dramatically reduced. Why? Because when we put
newly allocated block to the head, all further requests will occupy new
block, regardless remained space in other blocks. In this scenario all
requests come randomly. Eventually remained free space will be less
than requested size, free list will be iterated and it is possible that
nothing will be found there - finally new block will be created. So
exhaustion in random scenario happens for the maximum possible
allocation size: 32 pages for 32-bit system and 64 pages for 64-bit
system.
Also average cost of vm_map_ram was reduced from 1.017 us to 0.774 us.
Again this can be explained by iteration through smaller list of free
blocks.
3) Next simple scenario is a sequential allocation, when the allocation
order is increased for each block. This scenario forces allocator to
reach maximum amount of partially free blocks in a free list:
while (iters) {
/* Populate free list with blocks with remaining space */
for (order = 0; order <= ilog2(VMAP_MAX_ALLOC); order++) {
nr = VMAP_BBMAP_BITS / (1 << order);
/* Leave a hole */
nr -= 1;
for (i = 0; i < nr; i++) {
vaddr = vm_map_ram(pages, (1 << order), -1, PAGE_KERNEL);
vm_unmap_ram(vaddr, (1 << order));
}
/* Completely occupy blocks from a free list */
for (order = 0; order <= ilog2(VMAP_MAX_ALLOC); order++) {
vaddr = vm_map_ram(pages, (1 << order), -1, PAGE_KERNEL);
vm_unmap_ram(vaddr, (1 << order));
}
}
Results which I got:
BEFORE (all new blocks are put to the head of a free list)
# cat /sys/kernel/debug/tracing/trace_stat/function0
Function Hit Time Avg s^2
-------- --- ---- --- ---
vm_map_ram 2032000 399545.2 us 0.196 us 467123.7 us
vm_unmap_ram 2032000 363225.7 us 0.178 us 111405.9 us
alloc_vmap_area 7001 30627.76 us 4.374 us 495.755 us
free_vmap_block 6993 7011.685 us 1.002 us 159.090 us
AFTER (all new blocks are put to the tail of a free list)
# cat /sys/kernel/debug/tracing/trace_stat/function0
Function Hit Time Avg s^2
-------- --- ---- --- ---
vm_map_ram 2032000 394259.7 us 0.194 us 589395.9 us
vm_unmap_ram 2032000 292500.7 us 0.143 us 94181.08 us
alloc_vmap_area 7000 31103.11 us 4.443 us 703.225 us
free_vmap_block 7000 6750.844 us 0.964 us 119.112 us
SUMMARY:
No surprises here, almost all numbers are the same.
Fixing this fragmentation problem I also did some improvements in a
allocation logic of a new vmap block: occupy block immediately and get
rid of extra search in a free list.
Also I replaced dirty bitmap with min/max dirty range values to make the
logic simpler and slightly faster, since two longs comparison costs
less, than loop thru bitmap.
This patchset raises several questions:
Q: Think the problem you comments is already known so that I wrote comments
about it as "it could consume lots of address space through fragmentation".
Could you tell me about your situation and reason why it should be avoided?
Gioh Kim
A: Indeed, there was a commit 3643763 which adds explicit comment about
fragmentation. But fragmentation which is described in this comment caused
by mixing of long-lived and short-lived objects, when a whole block is pinned
in memory because some page slots are still in use. But here I am talking
about blocks which are free, nobody uses them, and allocator keeps them alive
forever, continuously allocating new blocks.
Q: I think that if you put newly allocated block to the tail of a free
list, below example would results in enormous performance degradation.
new block: 1MB (256 pages)
while (iters--) {
vm_map_ram(3 or something else not dividable for 256) * 85
vm_unmap_ram(3) * 85
}
On every iteration, it needs newly allocated block and it is put to the
tail of a free list so finding it consumes large amount of time.
Joonsoo Kim
A: Second patch in current patchset gets rid of extra search in a free list,
so new block will be immediately occupied..
Also, the scenario above is impossible, cause vm_map_ram allocates virtual
range in orders, i.e. 2^n. I.e. passing 3 to vm_map_ram you will allocate
4 slots in a block and 256 slots (capacity of a block) of course dividable
on 4, so block will be completely occupied.
But there is a worst case which we can achieve: each free block has a hole
equal to order size.
The maximum size of allocation is 64 pages for 64-bit system
(if you try to map more, original alloc_vmap_area will be called).
So the maximum order is 6. That means that worst case, before allocator
makes a decision to allocate a new block, is to iterate 7 blocks:
HEAD
1st block - has 1 page slot free (order 0)
2nd block - has 2 page slots free (order 1)
3rd block - has 4 page slots free (order 2)
4th block - has 8 page slots free (order 3)
5th block - has 16 page slots free (order 4)
6th block - has 32 page slots free (order 5)
7th block - has 64 page slots free (order 6)
TAIL
So the worst scenario on 64-bit system is that each CPU queue can have 7
blocks in a free list.
This can happen only and only if you allocate blocks increasing the order.
(as I did in the function written in the comment of the first patch)
This is weird and rare case, but still it is possible. Afterwards you will
get 7 blocks in a list.
All further requests should be placed in a newly allocated block or some
free slots should be found in a free list.
Seems it does not look dramatically awful.
This patch (of 3):
If suitable block can't be found, new block is allocated and put into a
head of a free list, so on next iteration this new block will be found
first.
That's bad, because old blocks in a free list will not get a chance to be
fully used, thus fragmentation will grow.
Let's consider this simple example:
#1 We have one block in a free list which is partially used, and where only
one page is free:
HEAD |xxxxxxxxx-| TAIL
^
free space for 1 page, order 0
#2 New allocation request of order 1 (2 pages) comes, new block is allocated
since we do not have free space to complete this request. New block is put
into a head of a free list:
HEAD |----------|xxxxxxxxx-| TAIL
#3 Two pages were occupied in a new found block:
HEAD |xx--------|xxxxxxxxx-| TAIL
^
two pages mapped here
#4 New allocation request of order 0 (1 page) comes. Block, which was created
on #2 step, is located at the beginning of a free list, so it will be found
first:
HEAD |xxX-------|xxxxxxxxx-| TAIL
^ ^
page mapped here, but better to use this hole
It is obvious, that it is better to complete request of #4 step using the
old block, where free space is left, because in other case fragmentation
will be highly increased.
But fragmentation is not only the case. The worst thing is that I can
easily create scenario, when the whole vmalloc space is exhausted by
blocks, which are not used, but already dirty and have several free pages.
Let's consider this function which execution should be pinned to one CPU:
static void exhaust_virtual_space(struct page *pages[16], int iters)
{
/* Firstly we have to map a big chunk, e.g. 16 pages.
* Then we have to occupy the remaining space with smaller
* chunks, i.e. 8 pages. At the end small hole should remain.
* So at the end of our allocation sequence block looks like
* this:
* XX big chunk
* |XXxxxxxxx-| x small chunk
* - hole, which is enough for a small chunk,
* but is not enough for a big chunk
*/
while (iters--) {
int i;
void *vaddr;
/* Map/unmap big chunk */
vaddr = vm_map_ram(pages, 16, -1, PAGE_KERNEL);
vm_unmap_ram(vaddr, 16);
/* Map/unmap small chunks.
*
* -1 for hole, which should be left at the end of each block
* to keep it partially used, with some free space available */
for (i = 0; i < (VMAP_BBMAP_BITS - 16) / 8 - 1; i++) {
vaddr = vm_map_ram(pages, 8, -1, PAGE_KERNEL);
vm_unmap_ram(vaddr, 8);
}
}
}
On every iteration new block (1MB of vm area in my case) will be
allocated and then will be occupied, without attempt to resolve small
allocation request using previously allocated blocks in a free list.
In case of random allocation (size should be randomly taken from the
range [1..64] in 64-bit case or [1..32] in 32-bit case) situation is the
same: new blocks continue to appear if maximum possible allocation size
(32 or 64) passed to the allocator, because all remaining blocks in a
free list do not have enough free space to complete this allocation
request.
In summary if new blocks are put into the head of a free list eventually
virtual space will be exhausted.
In current patch I simply put newly allocated block to the tail of a
free list, thus reduce fragmentation, giving a chance to resolve
allocation request using older blocks with possible holes left.
Signed-off-by: Roman Pen <r.peniaev@gmail.com>
Cc: Eric Dumazet <edumazet@google.com>
Acked-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: David Rientjes <rientjes@google.com>
Cc: WANG Chao <chaowang@redhat.com>
Cc: Fabian Frederick <fabf@skynet.be>
Cc: Christoph Lameter <cl@linux.com>
Cc: Gioh Kim <gioh.kim@lge.com>
Cc: Rob Jones <rob.jones@codethink.co.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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There is no point in overriding the size class below. It causes fatal
corruption on the next chunk on the 3264-bytes size class, which is the
last size class that is not huge.
For example, if the requested size was exactly 3264 bytes, current
zsmalloc allocates and returns a chunk from the size class of 3264 bytes,
not 4096. User access to this chunk may overwrite head of the next
adjacent chunk.
Here is the panic log captured when freelist was corrupted due to this:
Kernel BUG at ffffffc00030659c [verbose debug info unavailable]
Internal error: Oops - BUG: 96000006 [#1] PREEMPT SMP
Modules linked in:
exynos-snapshot: core register saved(CPU:5)
CPUMERRSR: 0000000000000000, L2MERRSR: 0000000000000000
exynos-snapshot: context saved(CPU:5)
exynos-snapshot: item - log_kevents is disabled
CPU: 5 PID: 898 Comm: kswapd0 Not tainted 3.10.61-4497415-eng #1
task: ffffffc0b8783d80 ti: ffffffc0b71e8000 task.ti: ffffffc0b71e8000
PC is at obj_idx_to_offset+0x0/0x1c
LR is at obj_malloc+0x44/0xe8
pc : [<ffffffc00030659c>] lr : [<ffffffc000306604>] pstate: a0000045
sp : ffffffc0b71eb790
x29: ffffffc0b71eb790 x28: ffffffc00204c000
x27: 000000000001d96f x26: 0000000000000000
x25: ffffffc098cc3500 x24: ffffffc0a13f2810
x23: ffffffc098cc3501 x22: ffffffc0a13f2800
x21: 000011e1a02006e3 x20: ffffffc0a13f2800
x19: ffffffbc02a7e000 x18: 0000000000000000
x17: 0000000000000000 x16: 0000000000000feb
x15: 0000000000000000 x14: 00000000a01003e3
x13: 0000000000000020 x12: fffffffffffffff0
x11: ffffffc08b264000 x10: 00000000e3a01004
x9 : ffffffc08b263fea x8 : ffffffc0b1e611c0
x7 : ffffffc000307d24 x6 : 0000000000000000
x5 : 0000000000000038 x4 : 000000000000011e
x3 : ffffffbc00003e90 x2 : 0000000000000cc0
x1 : 00000000d0100371 x0 : ffffffbc00003e90
Reported-by: Sooyong Suk <s.suk@samsung.com>
Signed-off-by: Heesub Shin <heesub.shin@samsung.com>
Tested-by: Sooyong Suk <s.suk@samsung.com>
Acked-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Due to missing bounds check the DAG pass of the BPF verifier can corrupt the memory which can cause random crashes during program loading: [8.449451] BUG: unable to handle kernel paging request at ffffffffffffffff [8.451293] IP: [<ffffffff811de33d>] kmem_cache_alloc_trace+0x8d/0x2f0 [8.452329] Oops: 0000 [#1] SMP [8.452329] Call Trace: [8.452329] [<ffffffff8116cc82>] bpf_check+0x852/0x2000 [8.452329] [<ffffffff8116b7e4>] bpf_prog_load+0x1e4/0x310 [8.452329] [<ffffffff811b190f>] ? might_fault+0x5f/0xb0 [8.452329] [<ffffffff8116c206>] SyS_bpf+0x806/0xa30 Fixes: f1bca82 ("bpf: add search pruning optimization to verifier") Signed-off-by: Alexei Starovoitov <ast@plumgrid.com> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
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When userland injects a SPI via the KVM_IRQ_LINE ioctl we currently only check it against a fixed limit, which historically is set to 127. With the new dynamic IRQ allocation the effective limit may actually be smaller (64). So when now a malicious or buggy userland injects a SPI in that range, we spill over on our VGIC bitmaps and bytemaps memory. I could trigger a host kernel NULL pointer dereference with current mainline by injecting some bogus IRQ number from a hacked kvmtool: ----------------- .... DEBUG: kvm_vgic_inject_irq(kvm, cpu=0, irq=114, level=1) DEBUG: vgic_update_irq_pending(kvm, cpu=0, irq=114, level=1) DEBUG: IRQ #114 still in the game, writing to bytemap now... Unable to handle kernel NULL pointer dereference at virtual address 00000000 pgd = ffffffc07652e000 [00000000] *pgd=00000000f658b003, *pud=00000000f658b003, *pmd=0000000000000000 Internal error: Oops: 96000006 [#1] PREEMPT SMP Modules linked in: CPU: 1 PID: 1053 Comm: lkvm-msi-irqinj Not tainted 4.0.0-rc7+ #3027 Hardware name: FVP Base (DT) task: ffffffc0774e9680 ti: ffffffc0765a8000 task.ti: ffffffc0765a8000 PC is at kvm_vgic_inject_irq+0x234/0x310 LR is at kvm_vgic_inject_irq+0x30c/0x310 pc : [<ffffffc0000ae0a8>] lr : [<ffffffc0000ae180>] pstate: 80000145 ..... So this patch fixes this by checking the SPI number against the actual limit. Also we remove the former legacy hard limit of 127 in the ioctl code. Signed-off-by: Andre Przywara <andre.przywara@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> CC: <stable@vger.kernel.org> # 4.0, 3.19, 3.18 [maz: wrap KVM_ARM_IRQ_GIC_MAX with #ifndef __KERNEL__, as suggested by Christopher Covington] Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
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This patch doesn't make any effect on previous behavior, since f2fs_write_data_page bypasses writing the page during POR. But, the difference is that this patch avoids holding writepages mutex. This is to avoid the following false warning, since this can happen only when mount and shutdown are triggered at the same time. ====================================================== [ INFO: possible circular locking dependency detected ] 4.0.0-rc1+ #3 Tainted: G O ------------------------------------------------------- kworker/u8:0/2270 is trying to acquire lock: (&sbi->gc_mutex){+.+.+.}, at: [<ffffffffa02bdd33>] f2fs_balance_fs+0x73/0x90 [f2fs] but task is already holding lock: (&sbi->writepages){+.+...}, at: [<ffffffffa02b261b>] f2fs_write_data_pages+0xcb/0x3a0 [f2fs] which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&sbi->writepages){+.+...}: [<ffffffff810e2b11>] lock_acquire+0xe1/0x2f0 [<ffffffff8185e1b3>] mutex_lock_nested+0x63/0x530 [<ffffffffa02b261b>] f2fs_write_data_pages+0xcb/0x3a0 [f2fs] [<ffffffff811c38c1>] do_writepages+0x21/0x50 [<ffffffff8126c5a6>] __writeback_single_inode+0x76/0xbf0 [<ffffffff8126e23a>] writeback_single_inode+0xea/0x1c0 [<ffffffff8126e425>] write_inode_now+0x95/0xa0 [<ffffffff81259dab>] iput+0x20b/0x3f0 [<ffffffffa02c1c8b>] recover_data.constprop.14+0x26b/0xa80 [f2fs] [<ffffffffa02c2776>] recover_fsync_data+0x2b6/0x5e0 [f2fs] [<ffffffffa02a9744>] f2fs_fill_super+0xb24/0xb90 [f2fs] [<ffffffff8123d7f4>] mount_bdev+0x1a4/0x1e0 [<ffffffffa02a3c85>] f2fs_mount+0x15/0x20 [f2fs] [<ffffffff8123e159>] mount_fs+0x39/0x180 [<ffffffff8125e51b>] vfs_kern_mount+0x6b/0x160 [<ffffffff81261554>] do_mount+0x204/0xbe0 [<ffffffff8126223b>] SyS_mount+0x8b/0xe0 [<ffffffff81863e6d>] system_call_fastpath+0x16/0x1b -> #1 (&sbi->cp_mutex){+.+...}: [<ffffffff810e2b11>] lock_acquire+0xe1/0x2f0 [<ffffffff8185e1b3>] mutex_lock_nested+0x63/0x530 [<ffffffffa02acbf2>] write_checkpoint+0x42/0x1230 [f2fs] [<ffffffffa02a847d>] f2fs_sync_fs+0x9d/0x2a0 [f2fs] [<ffffffff81272f82>] sync_filesystem+0x82/0xb0 [<ffffffff8123c214>] generic_shutdown_super+0x34/0x100 [<ffffffff8123c5f7>] kill_block_super+0x27/0x70 [<ffffffffa02a3c60>] kill_f2fs_super+0x20/0x30 [f2fs] [<ffffffff8123ca49>] deactivate_locked_super+0x49/0x80 [<ffffffff8123d05e>] deactivate_super+0x4e/0x70 [<ffffffff8125df63>] cleanup_mnt+0x43/0x90 [<ffffffff8125e002>] __cleanup_mnt+0x12/0x20 [<ffffffff810a82e4>] task_work_run+0xc4/0xf0 [<ffffffff8101f0bd>] do_notify_resume+0x8d/0xa0 [<ffffffff81864141>] int_signal+0x12/0x17 -> #0 (&sbi->gc_mutex){+.+.+.}: [<ffffffff810e2866>] __lock_acquire+0x1ac6/0x1c90 [<ffffffff810e2b11>] lock_acquire+0xe1/0x2f0 [<ffffffff8185e1b3>] mutex_lock_nested+0x63/0x530 [<ffffffffa02bdd33>] f2fs_balance_fs+0x73/0x90 [f2fs] [<ffffffffa02b5938>] f2fs_write_data_page+0x348/0x5b0 [f2fs] [<ffffffffa02af9da>] __f2fs_writepage+0x1a/0x50 [f2fs] [<ffffffff811c1b54>] write_cache_pages+0x274/0x6f0 [<ffffffffa02b2630>] f2fs_write_data_pages+0xe0/0x3a0 [f2fs] [<ffffffff811c38c1>] do_writepages+0x21/0x50 [<ffffffff8126c5a6>] __writeback_single_inode+0x76/0xbf0 [<ffffffff8126d44a>] writeback_sb_inodes+0x32a/0x710 [<ffffffff8126d8cf>] __writeback_inodes_wb+0x9f/0xd0 [<ffffffff8126dcdb>] wb_writeback+0x3db/0x850 [<ffffffff8126e848>] bdi_writeback_workfn+0x148/0x980 [<ffffffff810a3782>] process_one_work+0x1e2/0x840 [<ffffffff810a3f01>] worker_thread+0x121/0x460 [<ffffffff810a9dc8>] kthread+0xf8/0x110 [<ffffffff81863dbc>] ret_from_fork+0x7c/0xb0 Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
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We will encounter oops by executing below command. getfattr -n system.advise /mnt/f2fs/file Killed message log: BUG: unable to handle kernel NULL pointer dereference at (null) IP: [<f8b54d69>] f2fs_xattr_advise_get+0x29/0x40 [f2fs] *pdpt = 00000000319b7001 *pde = 0000000000000000 Oops: 0002 [#1] SMP Modules linked in: f2fs(O) snd_intel8x0 snd_ac97_codec ac97_bus snd_pcm snd_seq_midi snd_seq_midi_event snd_rawmidi snd_seq joydev snd_seq_device snd_timer bnep snd rfcomm microcode bluetooth soundcore i2c_piix4 mac_hid serio_raw parport_pc ppdev lp parport binfmt_misc hid_generic psmouse usbhid hid e1000 [last unloaded: f2fs] CPU: 3 PID: 3134 Comm: getfattr Tainted: G O 4.0.0-rc1 #6 Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006 task: f3a71b60 ti: f19a6000 task.ti: f19a6000 EIP: 0060:[<f8b54d69>] EFLAGS: 00010246 CPU: 3 EIP is at f2fs_xattr_advise_get+0x29/0x40 [f2fs] EAX: 00000000 EBX: f19a7e71 ECX: 00000000 EDX: f8b5b467 ESI: 00000000 EDI: f2008570 EBP: f19a7e14 ESP: f19a7e08 DS: 007b ES: 007b FS: 00d8 GS: 0033 SS: 0068 CR0: 80050033 CR2: 00000000 CR3: 319b8000 CR4: 000007f0 Stack: f8b5a634 c0cbb580 00000000 f19a7e34 c1193850 00000000 00000007 f19a7e71 f19a7e64 c0cbb580 c1193810 f19a7e50 c1193c00 00000000 00000000 00000000 c0cbb580 00000000 f19a7f70 c1194097 00000000 00000000 00000000 74737973 Call Trace: [<c1193850>] generic_getxattr+0x40/0x50 [<c1193810>] ? xattr_resolve_name+0x80/0x80 [<c1193c00>] vfs_getxattr+0x70/0xa0 [<c1194097>] getxattr+0x87/0x190 [<c11801d7>] ? path_lookupat+0x57/0x5f0 [<c11819d2>] ? putname+0x32/0x50 [<c116653a>] ? kmem_cache_alloc+0x2a/0x130 [<c11819d2>] ? putname+0x32/0x50 [<c11819d2>] ? putname+0x32/0x50 [<c11819d2>] ? putname+0x32/0x50 [<c11827f9>] ? user_path_at_empty+0x49/0x70 [<c118283f>] ? user_path_at+0x1f/0x30 [<c11941e7>] path_getxattr+0x47/0x80 [<c11948e7>] SyS_getxattr+0x27/0x30 [<c163f748>] sysenter_do_call+0x12/0x12 Code: 66 90 55 89 e5 57 56 53 66 66 66 66 90 8b 78 20 89 d3 ba 67 b4 b5 f8 89 d8 89 ce e8 42 7c 7b c8 85 c0 75 16 0f b6 87 44 01 00 00 <88> 06 b8 01 00 00 00 5b 5e 5f 5d c3 8d 76 00 b8 ea ff ff ff eb EIP: [<f8b54d69>] f2fs_xattr_advise_get+0x29/0x40 [f2fs] SS:ESP 0068:f19a7e08 CR2: 0000000000000000 ---[ end trace 860260654f1f416a ]--- The reason is that in getfattr there are two steps which is indicated by strace info: 1) try to lookup and get size of specified xattr. 2) get value of the extented attribute. strace info: getxattr("/mnt/f2fs/file", "system.advise", 0x0, 0) = 1 getxattr("/mnt/f2fs/file", "system.advise", "\x00", 256) = 1 For the first step, getfattr may pass a NULL pointer in @value and zero in @SiZe as parameters for ->getxattr, but we access this @value pointer directly without checking whether the pointer is valid or not in f2fs_xattr_advise_get, so the oops occurs. This patch fixes this issue by verifying @value pointer before using. Signed-off-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
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When having permanent EEH error, the PCI device will be removed from the system. For this case, we shouldn't set pcierr_recovery to true wrongly, which blocks the driver to release the allocated interrupts and their handlers. Eventually, we can't disable MSI or MSIx successfully because of the MSI or MSIx interrupts still have associated interrupt actions, which is turned into following stack dump. Oops: Exception in kernel mode, sig: 5 [#1] : [c0000000003b76a8] .free_msi_irqs+0x80/0x1a0 (unreliable) [c00000000039f388] .pci_remove_bus_device+0x98/0x110 [c0000000000790f4] .pcibios_remove_pci_devices+0x9c/0x128 [c000000000077b98] .handle_eeh_events+0x2d8/0x4b0 [c0000000000782d0] .eeh_event_handler+0x130/0x1c0 [c000000000022bd4] .kernel_thread+0x54/0x70 Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Acked-by: Prashant Sreedharan <prashant@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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When I added pfmemalloc support in build_skb(), I forgot netlink was using build_skb() with a vmalloc() area. In this patch I introduce __build_skb() for netlink use, and build_skb() is a wrapper handling both skb->head_frag and skb->pfmemalloc This means netlink no longer has to hack skb->head_frag [ 1567.700067] kernel BUG at arch/x86/mm/physaddr.c:26! [ 1567.700067] invalid opcode: 0000 [#1] PREEMPT SMP KASAN [ 1567.700067] Dumping ftrace buffer: [ 1567.700067] (ftrace buffer empty) [ 1567.700067] Modules linked in: [ 1567.700067] CPU: 9 PID: 16186 Comm: trinity-c182 Not tainted 4.0.0-next-20150424-sasha-00037-g4796e21 #2167 [ 1567.700067] task: ffff880127efb000 ti: ffff880246770000 task.ti: ffff880246770000 [ 1567.700067] RIP: __phys_addr (arch/x86/mm/physaddr.c:26 (discriminator 3)) [ 1567.700067] RSP: 0018:ffff8802467779d8 EFLAGS: 00010202 [ 1567.700067] RAX: 000041000ed8e000 RBX: ffffc9008ed8e000 RCX: 000000000000002c [ 1567.700067] RDX: 0000000000000004 RSI: 0000000000000000 RDI: ffffffffb3fd6049 [ 1567.700067] RBP: ffff8802467779f8 R08: 0000000000000019 R09: ffff8801d0168000 [ 1567.700067] R10: ffff8801d01680c7 R11: ffffed003a02d019 R12: ffffc9000ed8e000 [ 1567.700067] R13: 0000000000000f40 R14: 0000000000001180 R15: ffffc9000ed8e000 [ 1567.700067] FS: 00007f2a7da3f700(0000) GS:ffff8801d1000000(0000) knlGS:0000000000000000 [ 1567.700067] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 1567.700067] CR2: 0000000000738308 CR3: 000000022e329000 CR4: 00000000000007e0 [ 1567.700067] Stack: [ 1567.700067] ffffc9000ed8e000 ffff8801d0168000 ffffc9000ed8e000 ffff8801d0168000 [ 1567.700067] ffff880246777a28 ffffffffad7c0a21 0000000000001080 ffff880246777c08 [ 1567.700067] ffff88060d302e68 ffff880246777b58 ffff880246777b88 ffffffffad9a6821 [ 1567.700067] Call Trace: [ 1567.700067] build_skb (include/linux/mm.h:508 net/core/skbuff.c:316) [ 1567.700067] netlink_sendmsg (net/netlink/af_netlink.c:1633 net/netlink/af_netlink.c:2329) [ 1567.774369] ? sched_clock_cpu (kernel/sched/clock.c:311) [ 1567.774369] ? netlink_unicast (net/netlink/af_netlink.c:2273) [ 1567.774369] ? netlink_unicast (net/netlink/af_netlink.c:2273) [ 1567.774369] sock_sendmsg (net/socket.c:614 net/socket.c:623) [ 1567.774369] sock_write_iter (net/socket.c:823) [ 1567.774369] ? sock_sendmsg (net/socket.c:806) [ 1567.774369] __vfs_write (fs/read_write.c:479 fs/read_write.c:491) [ 1567.774369] ? get_lock_stats (kernel/locking/lockdep.c:249) [ 1567.774369] ? default_llseek (fs/read_write.c:487) [ 1567.774369] ? vtime_account_user (kernel/sched/cputime.c:701) [ 1567.774369] ? rw_verify_area (fs/read_write.c:406 (discriminator 4)) [ 1567.774369] vfs_write (fs/read_write.c:539) [ 1567.774369] SyS_write (fs/read_write.c:586 fs/read_write.c:577) [ 1567.774369] ? SyS_read (fs/read_write.c:577) [ 1567.774369] ? __this_cpu_preempt_check (lib/smp_processor_id.c:63) [ 1567.774369] ? trace_hardirqs_on_caller (kernel/locking/lockdep.c:2594 kernel/locking/lockdep.c:2636) [ 1567.774369] ? trace_hardirqs_on_thunk (arch/x86/lib/thunk_64.S:42) [ 1567.774369] system_call_fastpath (arch/x86/kernel/entry_64.S:261) Fixes: 79930f5 ("net: do not deplete pfmemalloc reserve") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Sasha Levin <sasha.levin@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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Commit 0223334 ("dm: optimize dm_mq_queue_rq to _not_ use kthread if using pure blk-mq") mistakenly removed free_rq_clone()'s clone->q check before testing clone->q->mq_ops. It was an oversight to discontinue that check for 1 of the 2 use-cases for free_rq_clone(): 1) free_rq_clone() called when an unmapped original request is requeued 2) free_rq_clone() called in the request-based IO completion path The clone->q check made sense for case #1 but not for #2. However, we cannot just reinstate the check as it'd mask a serious bug in the IO completion case #2 -- no in-flight request should have an uninitialized request_queue (basic block layer refcounting _should_ ensure this). The NULL pointer seen for case #1 is detailed here: https://www.redhat.com/archives/dm-devel/2015-April/msg00160.html Fix this free_rq_clone() NULL pointer by simply checking if the mapped_device's type is DM_TYPE_MQ_REQUEST_BASED (clone's queue is blk-mq) rather than checking clone->q->mq_ops. This avoids the need to dereference clone->q, but a WARN_ON_ONCE is added to let us know if an uninitialized clone request is being completed. Reported-by: Bart Van Assche <bart.vanassche@sandisk.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
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May 12, 2015
Francois Romieu says: ==================== via-rhine rework The series applies against davem-next as of 9dd3c79 ("drivers: net: xgene: fix kbuild warnings"). Patches #1..#4 avoid holes in the receive ring. Patch #5 is a small leftover cleanup for #1..#4. Patches #6 and #7 are fairly simple barrier stuff. Patch #8 closes some SMP transmit races - not that anyone really complained about these but it's a bit hard to handwave that they can be safely ignored. Some testing, especially SMP testing of course, would be welcome. . Changes since #2: - added dma_rmb barrier in vlan related patch 6. - s/wmb/dma_wmb/ in (*new*) patch 7 of 8. - added explicit SMP barriers in (*new*) patch 8 of 8. . Changes since #1: - turned wmb() into dma_wmb() as suggested by davem and Alexander Duyck in patch 1 of 6. - forgot to reset rx_head_desc in rhine_reset_rbufs in patch 4 of 6. - removed rx_head_desc altogether in (*new*) patch 5 of 6 - remoed some vlan receive uglyness in (*new*) patch 6 of 6. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
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Andrew Lunn says: ==================== More Marvell DSA refactring and fixup This patch setup continues the refactoring and cleanup of the Marvell DSA drivers. Patch #1 Centralizes the duplicated parts of port setup and global setup into the shared mv88e6xxx. Patch #2 Centralizes looping over the ports setting them up Patch #3 Uses mnemonics for the remaining register access in the drivers. Patch #4 The 6172 is actually a member of the 6352 family. This moves the probe code into the correct driver. Patch #5 Adds more members of the 6171 family to the 6171 driver. The new devices are untested. Patch #6 The 6185 is a member of the 6131 family. Add it to the probe code of the 6131 driver. Patch #7 and Patch #8 Simply the mutex's in mv88e6xxx.c. The SMI bus is the bottleneck, not the granularity of the mutex's so simply the code down to a single mutex. Patch #8 Fixes a false positive lockdep splat, due to nested uses of MDIO busses. Patch #9 Fixes another false positive lockdep splat with the transmit queue because of stacked Ethernet devices. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
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Perf top raise a warning if a kernel sample is collected but kernel map
is restricted. The warning message needs to dereference al.map->dso...
However, previous perf_event__preprocess_sample() doesn't always
guarantee al.map != NULL, for example, when kernel map is restricted.
This patch validates al.map before dereferencing, avoid the segfault.
Before this patch:
$ cat /proc/sys/kernel/kptr_restrict
1
$ perf top -p 120183
perf: Segmentation fault
-------- backtrace --------
/path/to/perf[0x509868]
/lib64/libc.so.6(+0x3545f)[0x7f9a1540045f]
/path/to/perf[0x448820]
/path/to/perf(cmd_top+0xe3c)[0x44a5dc]
/path/to/perf[0x4766a2]
/path/to/perf(main+0x5f5)[0x42e545]
/lib64/libc.so.6(__libc_start_main+0xf4)[0x7f9a153ecbd4]
/path/to/perf[0x42e674]
And gdb call trace:
Program received signal SIGSEGV, Segmentation fault.
perf_event__process_sample (machine=0xa44030, sample=0x7fffffffa4c0, evsel=0xa43b00, event=0x7ffff41c3000, tool=0x7fffffffa8a0)
at builtin-top.c:736
736 !RB_EMPTY_ROOT(&al.map->dso->symbols[MAP__FUNCTION]) ?
(gdb) bt
#0 perf_event__process_sample (machine=0xa44030, sample=0x7fffffffa4c0, evsel=0xa43b00, event=0x7ffff41c3000, tool=0x7fffffffa8a0)
at builtin-top.c:736
#1 perf_top__mmap_read_idx (top=top@entry=0x7fffffffa8a0, idx=idx@entry=0) at builtin-top.c:855
#2 0x000000000044a5dd in perf_top__mmap_read (top=0x7fffffffa8a0) at builtin-top.c:872
#3 __cmd_top (top=0x7fffffffa8a0) at builtin-top.c:997
#4 cmd_top (argc=<optimized out>, argv=<optimized out>, prefix=<optimized out>) at builtin-top.c:1267
#5 0x00000000004766a3 in run_builtin (p=p@entry=0x8a6ce8 <commands+264>, argc=argc@entry=3, argv=argv@entry=0x7fffffffdf70)
at perf.c:371
#6 0x000000000042e546 in handle_internal_command (argv=0x7fffffffdf70, argc=3) at perf.c:430
#7 run_argv (argv=0x7fffffffdcf0, argcp=0x7fffffffdcfc) at perf.c:474
#8 main (argc=3, argv=0x7fffffffdf70) at perf.c:589
(gdb)
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Zefan Li <lizefan@huawei.com>
Link: http://lkml.kernel.org/r/1429946703-80807-1-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Fix an oops happening due to typo in 297d716 [power_supply: Change ownership from driver to core]. Unable to handle kernel NULL pointer dereference at virtual address 00000050 pgd = c0004000 [00000050] *pgd=00000000 Internal error: Oops: 17 [#1] ARM Modules linked in: CPU: 0 PID: 1 Comm: swapper Not tainted 4.1.0-rc1+ #35 Hardware name: Sharp-Collie task: c381a720 ti: c381e000 task.ti: c381e000 PC is at collie_bat_get_property+0x10/0x258 LR is at collie_bat_get_property+0x10/0x258 pc : [<c0235d28>] lr : [<c0235d28>] psr: 20000013 sp : c381fd60 ip : 00000001 fp : 00000000 r10: c37b84c0 r9 : c068c9b8 r8 : c37b84a0 r7 : c37b84c0 r6 : c381fd84 r5 : 00000000 r4 : 00000000 r3 : c0369380 r2 : c381fd84 r1 : 00000000 r0 : 00000000 Flags: nzCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment kernel Control: 0000717f Table: c3784000 DAC: 00000017 Process swapper (pid: 1, stack limit = 0xc381e190) Stack: (0xc381fd60 to 0xc3820000) fd60: c0369380 00000000 c37c0000 c068c9b8 c37b84c0 c0234380 00000000 c0234bc0 fd80: c042fcec c37b84a0 c0357c64 00000000 c37b84c0 c37c0000 c37b84a0 c0234e98 fda0: c37be020 00000000 ff0a0004 c37b84c8 c37be020 c37b84c0 c042fcec c383dbc0 fdc0: c0364060 00000000 00000000 c01be6a8 00000000 c015b220 c37b84c8 c381fdf0 fde0: c37b84c8 c37b84c8 c37b84c8 c37be020 c041e278 c015b478 c04a45b4 c0045290 fe00: c381a720 c0345d50 00000001 c37bf020 c0e511d8 c00453c0 c0688058 c37b84c8 fe20: 00000000 c37b84c0 c37780c0 c0e511d8 c38e2f60 c0e52d24 c04a45b4 c01be134 fe40: c37b8550 c37b8550 00000000 c0347a8c c37b84a0 00000000 c37b84c0 c0369380 fe60: c37780c0 00000001 00000061 c02347a0 00000001 c0e52e6c c068d144 c37b77a0 fe80: 00000000 c068d164 00000000 c0235b3c 00000000 c067fbb4 00000000 c068d1e4 fea0: 00000000 00000000 00000000 00000000 00000000 00000000 c37b77a0 c068d144 fec0: c3778020 c06953c0 c049de68 c01d5f54 c0688800 c3778020 c068d144 c0688700 fee0: c06953c0 c01d6000 c0675b80 c0675b80 c37b77a0 c0009624 c381a720 c000d8dc ff00: 00000001 c381ff54 c048a500 c00453c0 c00095a0 20000153 ffffffff c000d8dc ff20: c049cbd0 00000001 c04aa064 00000007 c04a9fb0 00000006 c06953c0 c06953c0 ff40: c048a590 c04a45c0 c04a9ffc 00000006 c06953c0 c06953c0 c048a590 c04a45c0 ff60: 00000061 c048adf8 00000006 00000006 c048a590 c0036450 00000001 00000000 ff80: c00363ec 00000000 c033ee7c 00000000 00000000 00000000 00000000 00000000 ffa0: 00000000 c033ee84 00000000 c000a3c8 00000000 00000000 00000000 00000000 ffc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 ffe0: 00000000 00000000 00000000 00000000 00000013 00000000 00000000 00000000 [<c0235d28>] (collie_bat_get_property) from [<c0234380>] (power_supply_get_property+0x1c/0x28) [<c0234380>] (power_supply_get_property) from [<c0234bc0>] (power_supply_show_property+0x50/0x1dc) [<c0234bc0>] (power_supply_show_property) from [<c0234e98>] (power_supply_uevent+0x9c/0x1cc) [<c0234e98>] (power_supply_uevent) from [<c01be6a8>] (dev_uevent+0xb4/0x1d0) [<c01be6a8>] (dev_uevent) from [<c015b478>] (kobject_uevent_env+0x1cc/0x4f8) [<c015b478>] (kobject_uevent_env) from [<c01be134>] (device_add+0x374/0x524) [<c01be134>] (device_add) from [<c02347a0>] (__power_supply_register+0x120/0x180) [<c02347a0>] (__power_supply_register) from [<c0235b3c>] (collie_bat_probe+0xe8/0x1b4) [<c0235b3c>] (collie_bat_probe) from [<c01d5f54>] (ucb1x00_add_dev+0x30/0x88) [<c01d5f54>] (ucb1x00_add_dev) from [<c01d6000>] (ucb1x00_register_driver+0x54/0x78) [<c01d6000>] (ucb1x00_register_driver) from [<c0009624>] (do_one_initcall+0x84/0x1f4) [<c0009624>] (do_one_initcall) from [<c048adf8>] (kernel_init_freeable+0xf8/0x1b4) [<c048adf8>] (kernel_init_freeable) from [<c033ee84>] (kernel_init+0x8/0xec) [<c033ee84>] (kernel_init) from [<c000a3c8>] (ret_from_fork+0x14/0x2c) Code: e92d40f8 e1a05001 e1a06002 ebfff9bc (e5903050) ---[ end trace 447ee06b251d66b2 ]--- Fixes: 297d716 ("power_supply: Change ownership from driver to core") Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com> Signed-off-by: Sebastian Reichel <sre@kernel.org>
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memset() to 0 interfaces array before reusing usb_configuration structure. This commit fix bug: ln -s functions/acm.1 configs/c.1 ln -s functions/acm.2 configs/c.1 ln -s functions/acm.3 configs/c.1 echo "UDC name" > UDC echo "" > UDC rm configs/c.1/acm.* rmdir functions/* mkdir functions/ecm.usb0 ln -s functions/ecm.usb0 configs/c.1 echo "UDC name" > UDC [ 82.220969] Unable to handle kernel NULL pointer dereference at virtual address 00000000 [ 82.229009] pgd = c0004000 [ 82.231698] [00000000] *pgd=00000000 [ 82.235260] Internal error: Oops: 17 [#1] PREEMPT SMP ARM [ 82.240638] Modules linked in: [ 82.243681] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.0.0-rc2 #39 [ 82.249926] Hardware name: SAMSUNG EXYNOS (Flattened Device Tree) [ 82.256003] task: c07cd2f0 ti: c07c8000 task.ti: c07c8000 [ 82.261393] PC is at composite_setup+0xe3c/0x1674 [ 82.266073] LR is at composite_setup+0xf20/0x1674 [ 82.270760] pc : [<c03510d4>] lr : [<c03511b8>] psr: 600001d3 [ 82.270760] sp : c07c9df0 ip : c0806448 fp : ed8c9c9c [ 82.282216] r10: 00000001 r9 : 00000000 r8 : edaae918 [ 82.287425] r7 : ed551cc0 r6 : 00007fff r5 : 00000000 r4 : ed799634 [ 82.293934] r3 : 00000003 r2 : 00010002 r1 : edaae918 r0 : 0000002e [ 82.300446] Flags: nZCv IRQs off FIQs off Mode SVC_32 ISA ARM Segment kernel [ 82.307910] Control: 10c5387d Table: 6bc1804a DAC: 00000015 [ 82.313638] Process swapper/0 (pid: 0, stack limit = 0xc07c8210) [ 82.319627] Stack: (0xc07c9df0 to 0xc07ca000) [ 82.323969] 9de0: 00000000 c06e65f4 00000000 c07c9f68 [ 82.332130] 9e00: 00000067 c07c59ac 000003f7 edaae918 ed8c9c98 ed799690 eca2f140 200001d3 [ 82.340289] 9e20: ee79a2d8 c07c9e88 c07c5304 ffff55db 00010002 edaae810 edaae860 eda96d50 [ 82.348448] 9e40: 00000009 ee264510 00000007 c07ca444 edaae860 c0340890 c0827a40 ffff55e0 [ 82.356607] 9e60: c0827a40 eda96e40 ee264510 edaae810 00000000 edaae860 00000007 c07ca444 [ 82.364766] 9e80: edaae860 c0354170 c03407dc c033db4c edaae810 00000000 00000000 00000010 [ 82.372925] 9ea0: 00000032 c0341670 00000000 00000000 00000001 eda96e00 00000000 00000000 [ 82.381084] 9ec0: 00000000 00000032 c0803a23 ee1aa840 00000001 c005d54c 249e2450 00000000 [ 82.389244] 9ee0: 200001d3 ee1aa840 ee1aa8a0 ed84f4c0 00000000 c07c9f68 00000067 c07c59ac [ 82.397403] 9f00: 00000000 c005d688 ee1aa840 ee1aa8a0 c07db4b4 c006009c 00000032 00000000 [ 82.405562] 9f20: 00000001 c005ce20 c07c59ac c005cf34 f002000c c07ca780 c07c9f68 00000057 [ 82.413722] 9f40: f0020000 413fc090 00000001 c00086b4 c000f804 60000053 ffffffff c07c9f9c [ 82.421880] 9f60: c0803a20 c0011fc0 00000000 00000000 c07c9fb8 c001bee0 c07ca4f0 c057004c [ 82.430040] 9f80: c07ca4fc c0803a20 c0803a20 413fc090 00000001 00000000 01000000 c07c9fb0 [ 82.438199] 9fa0: c000f800 c000f804 60000053 ffffffff 00000000 c0050e70 c0803bc0 c0783bd8 [ 82.446358] 9fc0: ffffffff ffffffff c0783664 00000000 00000000 c07b13e8 00000000 c0803e54 [ 82.454517] 9fe0: c07ca480 c07b13e4 c07ce40c 4000406a 00000000 40008074 00000000 00000000 [ 82.462689] [<c03510d4>] (composite_setup) from [<c0340890>] (s3c_hsotg_complete_setup+0xb4/0x418) [ 82.471626] [<c0340890>] (s3c_hsotg_complete_setup) from [<c0354170>] (usb_gadget_giveback_request+0xc/0x10) [ 82.481429] [<c0354170>] (usb_gadget_giveback_request) from [<c033db4c>] (s3c_hsotg_complete_request+0xcc/0x12c) [ 82.491583] [<c033db4c>] (s3c_hsotg_complete_request) from [<c0341670>] (s3c_hsotg_irq+0x4fc/0x558) [ 82.500614] [<c0341670>] (s3c_hsotg_irq) from [<c005d54c>] (handle_irq_event_percpu+0x50/0x150) [ 82.509291] [<c005d54c>] (handle_irq_event_percpu) from [<c005d688>] (handle_irq_event+0x3c/0x5c) [ 82.518145] [<c005d688>] (handle_irq_event) from [<c006009c>] (handle_fasteoi_irq+0xd4/0x18c) [ 82.526650] [<c006009c>] (handle_fasteoi_irq) from [<c005ce20>] (generic_handle_irq+0x20/0x30) [ 82.535242] [<c005ce20>] (generic_handle_irq) from [<c005cf34>] (__handle_domain_irq+0x6c/0xdc) [ 82.543923] [<c005cf34>] (__handle_domain_irq) from [<c00086b4>] (gic_handle_irq+0x2c/0x6c) [ 82.552256] [<c00086b4>] (gic_handle_irq) from [<c0011fc0>] (__irq_svc+0x40/0x74) [ 82.559716] Exception stack(0xc07c9f68 to 0xc07c9fb0) [ 82.564753] 9f60: 00000000 00000000 c07c9fb8 c001bee0 c07ca4f0 c057004c [ 82.572913] 9f80: c07ca4fc c0803a20 c0803a20 413fc090 00000001 00000000 01000000 c07c9fb0 [ 82.581069] 9fa0: c000f800 c000f804 60000053 ffffffff [ 82.586113] [<c0011fc0>] (__irq_svc) from [<c000f804>] (arch_cpu_idle+0x30/0x3c) [ 82.593491] [<c000f804>] (arch_cpu_idle) from [<c0050e70>] (cpu_startup_entry+0x128/0x1a4) [ 82.601740] [<c0050e70>] (cpu_startup_entry) from [<c0783bd8>] (start_kernel+0x350/0x3bc) [ 82.609890] Code: 0a000002 e3530005 05975010 15975008 (e5953000) [ 82.615965] ---[ end trace f57d5f599a5f1bfa ]--- Most of kernel code assume that interface array in struct usb_configuration is NULL terminated. When gadget is composed with configfs configuration structure may be reused for different functions set. This bug happens because purge_configs_funcs() sets only next_interface_id to 0. Interface array still contains pointers to already freed interfaces. If in second try we add less interfaces than earlier we may access unallocated memory when trying to get interface descriptors. Signed-off-by: Krzysztof Opasiak <k.opasiak@samsung.com> Cc: <stable@vger.kernel.org> # 3.10+ Signed-off-by: Felipe Balbi <balbi@ti.com>
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On a math-emu bootup the following crash occurs: Initializing CPU#0 ------------[ cut here ]------------ kernel BUG at arch/x86/kernel/traps.c:779! invalid opcode: 0000 [#1] SMP [...] EIP is at do_device_not_available+0xe/0x70 [...] Call Trace: [<c18238e6>] error_code+0x5a/0x60 [<c1002bd0>] ? math_error+0x140/0x140 [<c100bbd9>] ? fpu__init_cpu+0x59/0xa0 [<c1012322>] cpu_init+0x202/0x330 [<c104509f>] ? __native_set_fixmap+0x1f/0x30 [<c1b56ab0>] trap_init+0x305/0x346 [<c1b548af>] start_kernel+0x1a5/0x35d [<c1b542b4>] i386_start_kernel+0x82/0x86 The reason is that in the following commit: b1276c4 ("x86/fpu: Initialize fpregs in fpu__init_cpu_generic()") I failed to consider math-emu's limitation that it cannot execute the FNINIT instruction in kernel mode. The long term fix might be to allow math-emu to execute (certain) kernel mode FPU instructions, but for now apply the safe (albeit somewhat ugly) fix: initialize the emulation state explicitly without trapping out to the FPU emulator. Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Quentin Casasnovas <quentin.casasnovas@oracle.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Hit the following splat testing VRF change for ipsec: [ 113.475692] =============================== [ 113.476194] [ INFO: suspicious RCU usage. ] [ 113.476667] 4.2.0-rc6-1+deb7u2+clUNRELEASED #3.2.65-1+deb7u2+clUNRELEASED Not tainted [ 113.477545] ------------------------------- [ 113.478013] /work/monster-14/dsa/kernel.git/include/linux/rcupdate.h:568 Illegal context switch in RCU read-side critical section! [ 113.479288] [ 113.479288] other info that might help us debug this: [ 113.479288] [ 113.480207] [ 113.480207] rcu_scheduler_active = 1, debug_locks = 1 [ 113.480931] 2 locks held by setkey/6829: [ 113.481371] #0: (&net->xfrm.xfrm_cfg_mutex){+.+.+.}, at: [<ffffffff814e9887>] pfkey_sendmsg+0xfb/0x213 [ 113.482509] #1: (rcu_read_lock){......}, at: [<ffffffff814e767f>] rcu_read_lock+0x0/0x6e [ 113.483509] [ 113.483509] stack backtrace: [ 113.484041] CPU: 0 PID: 6829 Comm: setkey Not tainted 4.2.0-rc6-1+deb7u2+clUNRELEASED #3.2.65-1+deb7u2+clUNRELEASED [ 113.485422] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.7.5.1-0-g8936dbb-20141113_115728-nilsson.home.kraxel.org 04/01/2014 [ 113.486845] 0000000000000001 ffff88001d4c7a98 ffffffff81518af2 ffffffff81086962 [ 113.487732] ffff88001d538480 ffff88001d4c7ac8 ffffffff8107ae75 ffffffff8180a154 [ 113.488628] 0000000000000b30 0000000000000000 00000000000000d0 ffff88001d4c7ad8 [ 113.489525] Call Trace: [ 113.489813] [<ffffffff81518af2>] dump_stack+0x4c/0x65 [ 113.490389] [<ffffffff81086962>] ? console_unlock+0x3d6/0x405 [ 113.491039] [<ffffffff8107ae75>] lockdep_rcu_suspicious+0xfa/0x103 [ 113.491735] [<ffffffff81064032>] rcu_preempt_sleep_check+0x45/0x47 [ 113.492442] [<ffffffff8106404d>] ___might_sleep+0x19/0x1c8 [ 113.493077] [<ffffffff81064268>] __might_sleep+0x6c/0x82 [ 113.493681] [<ffffffff81133190>] cache_alloc_debugcheck_before.isra.50+0x1d/0x24 [ 113.494508] [<ffffffff81134876>] kmem_cache_alloc+0x31/0x18f [ 113.495149] [<ffffffff814012b5>] skb_clone+0x64/0x80 [ 113.495712] [<ffffffff814e6f71>] pfkey_broadcast_one+0x3d/0xff [ 113.496380] [<ffffffff814e7b84>] pfkey_broadcast+0xb5/0x11e [ 113.497024] [<ffffffff814e82d1>] pfkey_register+0x191/0x1b1 [ 113.497653] [<ffffffff814e9770>] pfkey_process+0x162/0x17e [ 113.498274] [<ffffffff814e9895>] pfkey_sendmsg+0x109/0x213 In pfkey_sendmsg the net mutex is taken and then pfkey_broadcast takes the RCU lock. Since pfkey_broadcast takes the RCU lock the allocation argument is pointless since GFP_ATOMIC must be used between the rcu_read_{,un}lock. The one call outside of rcu can be done with GFP_KERNEL. Fixes: 7f6b9db ("af_key: locking change") Signed-off-by: David Ahern <dsa@cumulusnetworks.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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Sep 2, 2015
This patch fixes the following crash: general protection fault: 0000 [#1] SMP DEBUG_PAGEALLOC CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.2.0-rc7+ #166 Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 task: ffff88010656d280 ti: ffff880106570000 task.ti: ffff880106570000 RIP: 0010:[<ffffffff8182f91b>] [<ffffffff8182f91b>] dst_destroy+0xa6/0xef RSP: 0018:ffff880107603e38 EFLAGS: 00010202 RAX: 0000000000000001 RBX: ffff8800d225a000 RCX: ffffffff82250fd0 RDX: 0000000000000001 RSI: ffffffff82250fd0 RDI: 6b6b6b6b6b6b6b6b RBP: ffff880107603e58 R08: 0000000000000001 R09: 0000000000000001 R10: 000000000000b530 R11: ffff880107609000 R12: 0000000000000000 R13: ffffffff82343c40 R14: 0000000000000000 R15: ffffffff8182fb4f FS: 0000000000000000(0000) GS:ffff880107600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b CR2: 00007fcabd9d3000 CR3: 00000000d7279000 CR4: 00000000000006e0 Stack: ffffffff82250fd0 ffff8801077d6f00 ffffffff82253c40 ffff8800d225a000 ffff880107603e68 ffffffff8182fb5d ffff880107603f08 ffffffff810d795e ffffffff810d7648 ffff880106574000 ffff88010656d280 ffff88010656d280 Call Trace: <IRQ> [<ffffffff8182fb5d>] dst_destroy_rcu+0xe/0x1d [<ffffffff810d795e>] rcu_process_callbacks+0x618/0x7eb [<ffffffff810d7648>] ? rcu_process_callbacks+0x302/0x7eb [<ffffffff8182fb4f>] ? dst_gc_task+0x1eb/0x1eb [<ffffffff8107e11b>] __do_softirq+0x178/0x39f [<ffffffff8107e52e>] irq_exit+0x41/0x95 [<ffffffff81a4f215>] smp_apic_timer_interrupt+0x34/0x40 [<ffffffff81a4d5cd>] apic_timer_interrupt+0x6d/0x80 <EOI> [<ffffffff8100b968>] ? default_idle+0x21/0x32 [<ffffffff8100b966>] ? default_idle+0x1f/0x32 [<ffffffff8100bf19>] arch_cpu_idle+0xf/0x11 [<ffffffff810b0bc7>] default_idle_call+0x1f/0x21 [<ffffffff810b0dce>] cpu_startup_entry+0x1ad/0x273 [<ffffffff8102fe67>] start_secondary+0x135/0x156 dst is freed right before lwtstate_put(), this is not correct... Fixes: 61adedf ("route: move lwtunnel state to dst_entry") Acked-by: Jiri Benc <jbenc@redhat.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: Cong Wang <cwang@twopensource.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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rds_rdma_unuse() drops the mr reference count which it hasn't taken. Correct way of removing mr is to remove mr from the tree and then rdma_destroy_mr() it first, then rds_mr_put() to decrement its reference count. Whichever thread holds last reference will free the mr via rds_mr_put() This bug was triggering weird null pointer crashes. One if the trace for it is captured below. BUG: unable to handle kernel NULL pointer dereference at 0000000000000104 IP: [<ffffffffa0899471>] rds_ib_free_mr+0x31/0x130 [rds_rdma] PGD 4366fa067 PUD 4366f9067 PMD 0 Oops: 0000 [#1] SMP [...] task: ffff88046da6a000 ti: ffff88046da6c000 task.ti: ffff88046da6c000 RIP: 0010:[<ffffffffa0899471>] [<ffffffffa0899471>] rds_ib_free_mr+0x31/0x130 [rds_rdma] RSP: 0018:ffff88046fa43bd8 EFLAGS: 00010286 RAX: 0000000071d38b80 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000001 RSI: 0000000000000000 RDI: ffff880079e7ff40 RBP: ffff88046fa43bf8 R08: 0000000000000000 R09: 0000000000000000 R10: ffff88046fa43ca8 R11: ffff88046a802ed8 R12: ffff880079e7fa40 R13: 0000000000000000 R14: ffff880079e7ff40 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff88046fa40000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b CR2: 0000000000000104 CR3: 00000004366fb000 CR4: 00000000000006e0 Stack: ffff880079e7fa40 ffff880671d38f08 ffff880079e7ff40 0000000000000296 ffff88046fa43c28 ffffffffa087a38b ffff880079e7fa40 ffff880671d38f10 0000000000000000 0000000000000292 ffff88046fa43c48 ffffffffa087a3b6 Call Trace: <IRQ> [<ffffffffa087a38b>] rds_destroy_mr+0x8b/0xa0 [rds] [<ffffffffa087a3b6>] __rds_put_mr_final+0x16/0x30 [rds] [<ffffffffa087a492>] rds_rdma_unuse+0xc2/0x120 [rds] [<ffffffffa08766d3>] rds_recv_incoming_exthdrs+0x83/0xa0 [rds] [<ffffffffa0876782>] rds_recv_incoming+0x92/0x200 [rds] [<ffffffffa0895269>] rds_ib_process_recv+0x259/0x320 [rds_rdma] [<ffffffffa08962a8>] rds_ib_recv_tasklet_fn+0x1a8/0x490 [rds_rdma] [<ffffffff810dcd78>] ? __remove_hrtimer+0x58/0x90 [<ffffffff810799e1>] tasklet_action+0xb1/0xc0 [<ffffffff81079b52>] __do_softirq+0xe2/0x290 [<ffffffff81079df6>] irq_exit+0xa6/0xb0 [<ffffffff81613915>] do_IRQ+0x65/0xf0 [<ffffffff816118ab>] common_interrupt+0x6b/0x6b Signed-off-by: Santosh Shilimkar <ssantosh@kernel.org> Signed-off-by: Santosh Shilimkar <santosh.shilimkar@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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[ 1065.801569] Internal error: Oops: 96000006 [#1] SMP ... [ 1065.866655] Hardware name: AppliedMicro Mustang/Mustang, BIOS 1.1.0 Apr 22 2015 [ 1065.873937] Workqueue: events_power_efficient phy_state_machine [ 1065.879837] task: fffffe01de105e80 ti: fffffe00bcf18000 task.ti: fffffe00bcf18000 [ 1065.887288] PC is at linkwatch_fire_event+0xac/0xc0 [ 1065.892141] LR is at linkwatch_fire_event+0xa0/0xc0 [ 1065.896995] pc : [<fffffe000060284c>] lr : [<fffffe0000602840>] pstate: 200001c5 [ 1065.904356] sp : fffffe00bcf1bd00 ... [ 1066.196813] Call Trace: [ 1066.199248] [<fffffe000060284c>] linkwatch_fire_event+0xac/0xc0 [ 1066.205140] [<fffffe000061167c>] netif_carrier_off+0x54/0x64 [ 1066.210773] [<fffffe00004f1654>] phy_state_machine+0x120/0x3bc [ 1066.216578] [<fffffe00000d8d10>] process_one_work+0x15c/0x3a8 [ 1066.222296] [<fffffe00000d9090>] worker_thread+0x134/0x470 [ 1066.227757] [<fffffe00000df014>] kthread+0xe0/0xf8 [ 1066.232525] Code: 97f65ee9 f9420660 d538d082 8b000042 (885f7c40) The fix is to call phy_disconnect() from xgene_enet_mdio_remove, which in turn call cancel_delayed_work_sync(). Signed-off-by: Iyappan Subramanian <isubramanian@apm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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There may be lots of pending requests so that the buffer of PAGE_SIZE can't hold them at all. One typical example is scsi-mq, the queue depth(.can_queue) of scsi_host and blk-mq is quite big but scsi_device's queue_depth is a bit small(.cmd_per_lun), then it is quite easy to have lots of pending requests in hw queue. This patch fixes the following warning and the related memory destruction. [ 359.025101] fill_read_buffer: blk_mq_hw_sysfs_show+0x0/0x7d returned bad count^M [ 359.055595] irq event stamp: 15537^M [ 359.055606] general protection fault: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC ^M [ 359.055614] Dumping ftrace buffer:^M [ 359.055660] (ftrace buffer empty)^M [ 359.055672] Modules linked in: nbd ipv6 kvm_intel kvm serio_raw^M [ 359.055678] CPU: 4 PID: 21631 Comm: stress-ng-sysfs Not tainted 4.2.0-rc5-next-20150805 #434^M [ 359.055679] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011^M [ 359.055682] task: ffff8802161cc000 ti: ffff88021b4a8000 task.ti: ffff88021b4a8000^M [ 359.055693] RIP: 0010:[<ffffffff811541c5>] [<ffffffff811541c5>] __kmalloc+0xe8/0x152^M Cc: <stable@vger.kernel.org> Signed-off-by: Ming Lei <ming.lei@canonical.com> Signed-off-by: Jens Axboe <axboe@fb.com>
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Inside timeout handler, blk_mq_tag_to_rq() is called to retrieve the request from one tag. This way is obviously wrong because the request can be freed any time and some fiedds of the request can't be trusted, then kernel oops might be triggered[1]. Currently wrt. blk_mq_tag_to_rq(), the only special case is that the flush request can share same tag with the request cloned from, and the two requests can't be active at the same time, so this patch fixes the above issue by updating tags->rqs[tag] with the active request(either flush rq or the request cloned from) of the tag. Also blk_mq_tag_to_rq() gets much simplified with this patch. Given blk_mq_tag_to_rq() is mainly for drivers and the caller must make sure the request can't be freed, so in bt_for_each() this helper is replaced with tags->rqs[tag]. [1] kernel oops log [ 439.696220] BUG: unable to handle kernel NULL pointer dereference at 0000000000000158^M [ 439.697162] IP: [<ffffffff812d89ba>] blk_mq_tag_to_rq+0x21/0x6e^M [ 439.700653] PGD 7ef765067 PUD 7ef764067 PMD 0 ^M [ 439.700653] Oops: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC ^M [ 439.700653] Dumping ftrace buffer:^M [ 439.700653] (ftrace buffer empty)^M [ 439.700653] Modules linked in: nbd ipv6 kvm_intel kvm serio_raw^M [ 439.700653] CPU: 6 PID: 2779 Comm: stress-ng-sigfd Not tainted 4.2.0-rc5-next-20150805+ #265^M [ 439.730500] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011^M [ 439.730500] task: ffff880605308000 ti: ffff88060530c000 task.ti: ffff88060530c000^M [ 439.730500] RIP: 0010:[<ffffffff812d89ba>] [<ffffffff812d89ba>] blk_mq_tag_to_rq+0x21/0x6e^M [ 439.730500] RSP: 0018:ffff880819203da0 EFLAGS: 00010283^M [ 439.730500] RAX: ffff880811b0e000 RBX: ffff8800bb465f00 RCX: 0000000000000002^M [ 439.730500] RDX: 0000000000000000 RSI: 0000000000000202 RDI: 0000000000000000^M [ 439.730500] RBP: ffff880819203db0 R08: 0000000000000002 R09: 0000000000000000^M [ 439.730500] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000202^M [ 439.730500] R13: ffff880814104800 R14: 0000000000000002 R15: ffff880811a2ea00^M [ 439.730500] FS: 00007f165b3f5740(0000) GS:ffff880819200000(0000) knlGS:0000000000000000^M [ 439.730500] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b^M [ 439.730500] CR2: 0000000000000158 CR3: 00000007ef766000 CR4: 00000000000006e0^M [ 439.730500] Stack:^M [ 439.730500] 0000000000000008 ffff8808114eed90 ffff880819203e00 ffffffff812dc104^M [ 439.755663] ffff880819203e40 ffffffff812d9f5e 0000020000000000 ffff8808114eed80^M [ 439.755663] Call Trace:^M [ 439.755663] <IRQ> ^M [ 439.755663] [<ffffffff812dc104>] bt_for_each+0x6e/0xc8^M [ 439.755663] [<ffffffff812d9f5e>] ? blk_mq_rq_timed_out+0x6a/0x6a^M [ 439.755663] [<ffffffff812d9f5e>] ? blk_mq_rq_timed_out+0x6a/0x6a^M [ 439.755663] [<ffffffff812dc1b3>] blk_mq_tag_busy_iter+0x55/0x5e^M [ 439.755663] [<ffffffff812d88b4>] ? blk_mq_bio_to_request+0x38/0x38^M [ 439.755663] [<ffffffff812d8911>] blk_mq_rq_timer+0x5d/0xd4^M [ 439.755663] [<ffffffff810a3e10>] call_timer_fn+0xf7/0x284^M [ 439.755663] [<ffffffff810a3d1e>] ? call_timer_fn+0x5/0x284^M [ 439.755663] [<ffffffff812d88b4>] ? blk_mq_bio_to_request+0x38/0x38^M [ 439.755663] [<ffffffff810a46d6>] run_timer_softirq+0x1ce/0x1f8^M [ 439.755663] [<ffffffff8104c367>] __do_softirq+0x181/0x3a4^M [ 439.755663] [<ffffffff8104c76e>] irq_exit+0x40/0x94^M [ 439.755663] [<ffffffff81031482>] smp_apic_timer_interrupt+0x33/0x3e^M [ 439.755663] [<ffffffff815559a4>] apic_timer_interrupt+0x84/0x90^M [ 439.755663] <EOI> ^M [ 439.755663] [<ffffffff81554350>] ? _raw_spin_unlock_irq+0x32/0x4a^M [ 439.755663] [<ffffffff8106a98b>] finish_task_switch+0xe0/0x163^M [ 439.755663] [<ffffffff8106a94d>] ? finish_task_switch+0xa2/0x163^M [ 439.755663] [<ffffffff81550066>] __schedule+0x469/0x6cd^M [ 439.755663] [<ffffffff8155039b>] schedule+0x82/0x9a^M [ 439.789267] [<ffffffff8119b28b>] signalfd_read+0x186/0x49a^M [ 439.790911] [<ffffffff8106d86a>] ? wake_up_q+0x47/0x47^M [ 439.790911] [<ffffffff811618c2>] __vfs_read+0x28/0x9f^M [ 439.790911] [<ffffffff8117a289>] ? __fget_light+0x4d/0x74^M [ 439.790911] [<ffffffff811620a7>] vfs_read+0x7a/0xc6^M [ 439.790911] [<ffffffff8116292b>] SyS_read+0x49/0x7f^M [ 439.790911] [<ffffffff81554c17>] entry_SYSCALL_64_fastpath+0x12/0x6f^M [ 439.790911] Code: 48 89 e5 e8 a9 b8 e7 ff 5d c3 0f 1f 44 00 00 55 89 f2 48 89 e5 41 54 41 89 f4 53 48 8b 47 60 48 8b 1c d0 48 8b 7b 30 48 8b 53 38 <48> 8b 87 58 01 00 00 48 85 c0 75 09 48 8b 97 88 0c 00 00 eb 10 ^M [ 439.790911] RIP [<ffffffff812d89ba>] blk_mq_tag_to_rq+0x21/0x6e^M [ 439.790911] RSP <ffff880819203da0>^M [ 439.790911] CR2: 0000000000000158^M [ 439.790911] ---[ end trace d40af58949325661 ]---^M Cc: <stable@vger.kernel.org> Signed-off-by: Ming Lei <ming.lei@canonical.com> Signed-off-by: Jens Axboe <axboe@fb.com>
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In brcmf_bus_start() the function brcmf_cfg80211_attach() is called which may fail. If this happens we should not call brcmf_cfg80211_detach() in the failure path as it will result in NULL pointer dereference: brcmf_fweh_activate_events: Set event_msgs error (-5) brcmf_bus_start: failed: -5 brcmf_sdio_firmware_callback: dongle is not responding BUG: unable to handle kernel NULL pointer dereference at 0000000000000068 IP: [<ffffffff811e8f08>] kernfs_find_ns+0x18/0xd0 PGD 0 Oops: 0000 [#1] SMP Modules linked in: brcmfmac(O) brcmutil(O) cfg80211 auth_rpcgss CPU: 1 PID: 45 Comm: kworker/1:1 Tainted: G O Hardware name: Dell Inc. Latitude E6410/07XJP9, BIOS A07 02/15/2011 Workqueue: events request_firmware_work_func task: ffff880036c09ac0 ti: ffff880036dd4000 task.ti: ffff880036dd4000 RIP: 0010:[<ffffffff811e8f08>] [<ffffffff811e8f08>] kernfs_find_ns+0x18/0xd0 RSP: 0018:ffff880036dd7a28 EFLAGS: 00010246 RAX: ffff880036c09ac0 RBX: 0000000000000000 RCX: 000000007fffffff RDX: 0000000000000000 RSI: ffffffff816578b9 RDI: 0000000000000000 RBP: ffff880036dd7a48 R08: 0000000000000000 R09: ffff880036c0b340 R10: 00000000000002ec R11: ffff880036dd7b08 R12: ffffffff816578b9 R13: 0000000000000000 R14: ffffffff816578b9 R15: ffff8800c6c87000 FS: 0000000000000000(0000) GS:ffff88012bc40000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b CR2: 0000000000000068 CR3: 0000000001a0b000 CR4: 00000000000006e0 Stack: 0000000000000000 ffffffff816578b9 0000000000000000 ffff8800c0d003c8 ffff880036dd7a78 ffffffff811e8ff5 0000000ffffffff1 ffffffff81a9b060 ffff8800c789f880 ffff8800c0d00000 ffff880036dd7a98 ffffffff811ebe0d Call Trace: [<ffffffff811e8ff5>] kernfs_find_and_get_ns+0x35/0x60 [<ffffffff811ebe0d>] sysfs_unmerge_group+0x1d/0x60 [<ffffffff81404ef2>] dpm_sysfs_remove+0x22/0x60 [<ffffffff813f9db9>] device_del+0x49/0x240 [<ffffffff815da768>] rfkill_unregister+0x58/0xc0 [<ffffffffa06bd91b>] wiphy_unregister+0xab/0x2f0 [cfg80211] [<ffffffffa0742fe3>] brcmf_cfg80211_detach+0x23/0x50 [brcmfmac] [<ffffffffa074d986>] brcmf_detach+0x86/0xe0 [brcmfmac] [<ffffffffa0757de8>] brcmf_sdio_remove+0x48/0x120 [brcmfmac] [<ffffffffa0758ed9>] brcmf_sdiod_remove+0x29/0xd0 [brcmfmac] [<ffffffffa0759031>] brcmf_ops_sdio_remove+0xb1/0x110 [brcmfmac] [<ffffffffa001c267>] sdio_bus_remove+0x37/0x100 [mmc_core] [<ffffffff813fe026>] __device_release_driver+0x96/0x130 [<ffffffff813fe0e3>] device_release_driver+0x23/0x30 [<ffffffffa0754bc8>] brcmf_sdio_firmware_callback+0x2a8/0x5d0 [brcmfmac] [<ffffffffa074deaf>] brcmf_fw_request_nvram_done+0x15f/0x5e0 [brcmfmac] [<ffffffff8140142f>] ? devres_add+0x3f/0x50 [<ffffffff810642b5>] ? usermodehelper_read_unlock+0x15/0x20 [<ffffffff81400000>] ? platform_match+0x70/0xa0 [<ffffffff8140f400>] request_firmware_work_func+0x30/0x60 [<ffffffff8106828c>] process_one_work+0x14c/0x3d0 [<ffffffff8106862a>] worker_thread+0x11a/0x450 [<ffffffff81068510>] ? process_one_work+0x3d0/0x3d0 [<ffffffff8106d692>] kthread+0xd2/0xf0 [<ffffffff8106d5c0>] ? kthread_create_on_node+0x180/0x180 [<ffffffff815ed35f>] ret_from_fork+0x3f/0x70 [<ffffffff8106d5c0>] ? kthread_create_on_node+0x180/0x180 Code: e9 40 fe ff ff 48 89 d8 eb 87 66 0f 1f 84 00 00 00 00 00 66 66 66 66 90 55 48 89 e5 41 56 49 89 f6 41 55 49 89 d5 31 d2 41 54 53 <0f> b7 47 68 48 8b 5f 48 66 c1 e8 05 83 e0 01 4d 85 ed 0f b6 c8 RIP [<ffffffff811e8f08>] kernfs_find_ns+0x18/0xd0 RSP <ffff880036dd7a28> CR2: 0000000000000068 ---[ end trace 87d6ec0d3fe46740 ]--- Reported-by: Daniel (Deognyoun) Kim <dekim@broadcom.com> Reviewed-by: Hante Meuleman <meuleman@broadcom.com> Reviewed-by: Franky (Zhenhui) Lin <frankyl@broadcom.com> Reviewed-by: Pieter-Paul Giesberts <pieterpg@broadcom.com> Signed-off-by: Arend van Spriel <arend@broadcom.com> Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
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Align fields reg_ch_conf_last and reg_ch_conf_pending of
struct wl1271{} to 64bit.
Without this, on 64bit ARM, wlcore_set_pending_regdomain_ch() fails at
the point it calls set_bit(ch_bit_idx, (long*)wl->reg_ch_conf_pending);
Here is the error message while doing iw wlan0 scan or connect:
[ 10.666857] wlcore: IRQ work
[ 10.670046] wlcore: intr: 0x40 (fw_rx_counter = 1, drv_rx_counter = 0, tx_results_counter = 0)
[ 10.678697] wlcore: WL1271_ACX_INTR_DATA
[ 10.682810] Unhandled fault: alignment fault (0x96000021) at 0xffffffc037a817f4
[ 10.690139] Internal error: : 96000021 [#1] PREEMPT SMP
[ 10.695366] Modules linked in:
[ 10.698437] CPU: 3 PID: 894 Comm: irq/60-wl18xx Tainted: G W 4.2.0-rc6-linaro-hikey #2
[ 10.707501] Hardware name: HiKey Development Board (DT)
[ 10.712733] task: ffffffc03a9d1680 ti: ffffffc039e18000 task.ti: ffffffc039e18000
[ 10.720239] PC is at set_bit+0x14/0x30
[ 10.724002] LR is at wlcore_set_pending_regdomain_ch+0x40/0x4c
Signed-off-by: Guodong Xu <guodong.xu@linaro.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
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Oct 19, 2015
commit c62987b ("bridge: push bridge setting ageing_time down to switchdev") introduced a timer race condition because the gc_timer can get rearmed after it's supposedly stopped and flushed in br_dev_delete() leading to a use of freed memory. So take rtnl to sync with bridge destruction when setting ageing_timer. Here's the trace reproduced with these two commands running in parallel: while :; do echo 10000 > /sys/class/net/br0/bridge/ageing_timer; done; while :; do brctl addbr br0; ip l set br0 up; ip l set br0 down; brctl delbr br0; done; [ 300.000029] BUG: unable to handle kernel paging request at ffffffff811c59d3 [ 300.000263] IP: [<ffffffff810f168e>] __internal_add_timer+0x2e/0xd0 [ 300.000422] PGD 1a0f067 PUD 1a10063 PMD 10001e1 [ 300.000639] Oops: 0003 [#1] SMP [ 300.000793] Modules linked in: bridge stp llc nfsd auth_rpcgss oid_registry nfs_acl nfs lockd grace fscache sunrpc crct10dif_pclmul crc32_pclmul crc32c_intel ghash_clmulni_intel ppdev aesni_intel aes_x86_64 glue_helper lrw gf128mul ablk_helper cryptd snd_hda_codec_generic qxl drm_kms_helper psmouse pcspkr ttm snd_hda_intel 9pnet_virtio evdev serio_raw joydev snd_hda_codec 9pnet virtio_balloon drm snd_hwdep virtio_console snd_hda_core pvpanic snd_pcm i2c_piix4 snd_timer acpi_cpufreq parport_pc snd parport soundcore button processor i2c_core ipv6 autofs4 hid_generic usbhid hid ext4 crc16 mbcache jbd2 sg sr_mod cdrom ata_generic virtio_blk virtio_net e1000 ehci_pci uhci_hcd ehci_hcd usbcore usb_common floppy ata_piix libata virtio_pci virtio_ring virtio scsi_mod [ 300.004008] CPU: 1 PID: 1169 Comm: bash Not tainted 4.3.0-rc3+ #46 [ 300.004008] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 [ 300.004008] task: ffff880035be2200 ti: ffff88003795c000 task.ti: ffff88003795c000 [ 300.004008] RIP: 0010:[<ffffffff810f168e>] [<ffffffff810f168e>] __internal_add_timer+0x2e/0xd0 [ 300.004008] RSP: 0018:ffff88003fd03e78 EFLAGS: 00010046 [ 300.004008] RAX: ffff88003fd0ef60 RBX: 840fc78949c08548 RCX: 00000001ffffffff [ 300.004008] RDX: 0000000000000000 RSI: ffffffff811c59d3 RDI: ffff88003fd0df00 [ 300.004008] RBP: ffff88003fd03e78 R08: 00000000ffffffff R09: 0000000000000000 [ 300.004008] R10: 0000000000000000 R11: 0000000000000000 R12: ffff88003fd0df00 [ 300.004008] R13: 0000000000000000 R14: 0000000000000001 R15: ffffffff816032e0 [ 300.004008] FS: 00007fcbdd609700(0000) GS:ffff88003fd00000(0000) knlGS:0000000000000000 [ 300.004008] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 300.004008] CR2: ffffffff811c59d3 CR3: 0000000037879000 CR4: 00000000000406e0 [ 300.004008] Stack: [ 300.004008] ffff88003fd03ea8 ffffffff810f1775 ffff88003c8cb958 ffff88003fd0df00 [ 300.004008] 0000000000000000 0000000000000001 ffff88003fd03f18 ffffffff810f28c4 [ 300.004008] ffff88003fd0eb68 ffff88003fd0e968 ffff88003fd0e768 ffff88003fd0df68 [ 300.004008] Call Trace: [ 300.004008] <IRQ> [ 300.004008] [<ffffffff810f1775>] cascade+0x45/0x70 [ 300.004008] [<ffffffff810f28c4>] run_timer_softirq+0x2f4/0x340 [ 300.004008] [<ffffffff8107e380>] __do_softirq+0xd0/0x440 [ 300.004008] [<ffffffff8107e8a3>] irq_exit+0xb3/0xc0 [ 300.004008] [<ffffffff815c2032>] smp_apic_timer_interrupt+0x42/0x50 [ 300.004008] [<ffffffff815bfe37>] apic_timer_interrupt+0x87/0x90 [ 300.004008] <EOI> [ 300.004008] [<ffffffff811fb80c>] ? create_object+0x13c/0x2e0 [ 300.004008] [<ffffffff8109b23e>] ? __kernel_text_address+0x4e/0x70 [ 300.004008] [<ffffffff8109b23e>] ? __kernel_text_address+0x4e/0x70 [ 300.004008] [<ffffffff8101e17f>] print_context_stack+0x7f/0xf0 [ 300.004008] [<ffffffff8101d55b>] dump_trace+0x11b/0x300 [ 300.004008] [<ffffffff8102970b>] save_stack_trace+0x2b/0x50 [ 300.004008] [<ffffffff811fb80c>] create_object+0x13c/0x2e0 [ 300.004008] [<ffffffff815b2e8e>] kmemleak_alloc+0x4e/0xb0 [ 300.004008] [<ffffffff811e475d>] kmem_cache_alloc_trace+0x18d/0x2f0 [ 300.004008] [<ffffffff8128b139>] kernfs_fop_open+0xc9/0x380 [ 300.004008] [<ffffffff8120214f>] do_dentry_open+0x1ff/0x2f0 [ 300.004008] [<ffffffff8128b070>] ? kernfs_fop_release+0x70/0x70 [ 300.004008] [<ffffffff812034f9>] vfs_open+0x59/0x60 [ 300.004008] [<ffffffff812130de>] path_openat+0x1ce/0x1260 [ 300.004008] [<ffffffff812154ae>] do_filp_open+0x7e/0xe0 [ 300.004008] [<ffffffff812251ff>] ? __alloc_fd+0xaf/0x180 [ 300.004008] [<ffffffff8120387b>] do_sys_open+0x12b/0x210 [ 300.004008] [<ffffffff8120397e>] SyS_open+0x1e/0x20 [ 300.004008] [<ffffffff815bf0b6>] entry_SYSCALL_64_fastpath+0x16/0x7a [ 300.004008] Code: 66 90 48 8b 46 10 48 8b 4f 40 55 48 89 c2 48 89 e5 48 29 ca 48 81 fa ff 00 00 00 77 20 0f b6 c0 48 8d 44 c7 68 48 8b 10 48 85 d2 <48> 89 16 74 04 48 89 72 08 48 89 30 48 89 46 08 5d c3 48 81 fa [ 300.004008] RIP [<ffffffff810f168e>] __internal_add_timer+0x2e/0xd0 [ 300.004008] RSP <ffff88003fd03e78> [ 300.004008] CR2: ffffffff811c59d3 Fixes: c62987b ("bridge: push bridge setting ageing_time down to switchdev") Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Reviewed-by: Jiri Pirko <jiri@mellanox.com> Acked-by: Scott Feldman <sfeldma@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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Or Gerlitz says: ==================== Mellanox driver update, Oct 14 2015 This series contains two more patches from Eli, patch from Majd to support PCI error handlers and a fix from Jack to mlx4 VFs when probed without a provisioned mac address. The patch set applied on top of net-next commit bbb300e "Merge branch 'bridge-vlan'" changes from V0: - made the health flag int --> bool to address comment from Dave on patch #1 - fixed sparse warning noted by the 0-day build tests in patch #2 ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
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A line discipline which does not define a receive_buf() method can
can cause a GPF if data is ever received [1]. Oddly, this was known
to the author of n_tracesink in 2011, but never fixed.
[1] GPF report
BUG: unable to handle kernel NULL pointer dereference at (null)
IP: [< (null)>] (null)
PGD 3752d067 PUD 37a7b067 PMD 0
Oops: 0010 [#1] SMP KASAN
Modules linked in:
CPU: 2 PID: 148 Comm: kworker/u10:2 Not tainted 4.4.0-rc2+ #51
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
Workqueue: events_unbound flush_to_ldisc
task: ffff88006da94440 ti: ffff88006db60000 task.ti: ffff88006db60000
RIP: 0010:[<0000000000000000>] [< (null)>] (null)
RSP: 0018:ffff88006db67b50 EFLAGS: 00010246
RAX: 0000000000000102 RBX: ffff88003ab32f88 RCX: 0000000000000102
RDX: 0000000000000000 RSI: ffff88003ab330a6 RDI: ffff88003aabd388
RBP: ffff88006db67c48 R08: ffff88003ab32f9c R09: ffff88003ab31fb0
R10: ffff88003ab32fa8 R11: 0000000000000000 R12: dffffc0000000000
R13: ffff88006db67c20 R14: ffffffff863df820 R15: ffff88003ab31fb8
FS: 0000000000000000(0000) GS:ffff88006dc00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: 0000000000000000 CR3: 0000000037938000 CR4: 00000000000006e0
Stack:
ffffffff829f46f1 ffff88006da94bf8 ffff88006da94bf8 0000000000000000
ffff88003ab31fb0 ffff88003aabd438 ffff88003ab31ff8 ffff88006430fd90
ffff88003ab32f9c ffffed0007557a87 1ffff1000db6cf78 ffff88003ab32078
Call Trace:
[<ffffffff8127cf91>] process_one_work+0x8f1/0x17a0 kernel/workqueue.c:2030
[<ffffffff8127df14>] worker_thread+0xd4/0x1180 kernel/workqueue.c:2162
[<ffffffff8128faaf>] kthread+0x1cf/0x270 drivers/block/aoe/aoecmd.c:1302
[<ffffffff852a7c2f>] ret_from_fork+0x3f/0x70 arch/x86/entry/entry_64.S:468
Code: Bad RIP value.
RIP [< (null)>] (null)
RSP <ffff88006db67b50>
CR2: 0000000000000000
---[ end trace a587f8947e54d6ea ]---
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Dave Jones found a warning from kasan in setup_cluster_bitmaps() ================================================================== BUG: KASAN: stack-out-of-bounds in setup_cluster_bitmap+0xc4/0x5a0 at addr ffff88039bef6828 Read of size 8 by task nfsd/1009 page:ffffea000e6fbd80 count:0 mapcount:0 mapping: (null) index:0x0 flags: 0x8000000000000000() page dumped because: kasan: bad access detected CPU: 1 PID: 1009 Comm: nfsd Tainted: G W 4.4.0-rc3-backup-debug+ #1 ffff880065647b50 000000006bb712c2 ffff88039bef6640 ffffffffa680a43e 0000004559c00000 ffff88039bef66c8 ffffffffa62638d1 ffffffffa61121c0 ffff8803a5769de8 0000000000000296 ffff8803a5769df0 0000000000046280 Call Trace: [<ffffffffa680a43e>] dump_stack+0x4b/0x6d [<ffffffffa62638d1>] kasan_report_error+0x501/0x520 [<ffffffffa61121c0>] ? debug_show_all_locks+0x1e0/0x1e0 [<ffffffffa6263948>] kasan_report+0x58/0x60 [<ffffffffa6814b00>] ? rb_last+0x10/0x40 [<ffffffffa66f8af4>] ? setup_cluster_bitmap+0xc4/0x5a0 [<ffffffffa6262ead>] __asan_load8+0x5d/0x70 [<ffffffffa66f8af4>] setup_cluster_bitmap+0xc4/0x5a0 [<ffffffffa66f675a>] ? setup_cluster_no_bitmap+0x6a/0x400 [<ffffffffa66fcd16>] btrfs_find_space_cluster+0x4b6/0x640 [<ffffffffa66fc860>] ? btrfs_alloc_from_cluster+0x4e0/0x4e0 [<ffffffffa66fc36e>] ? btrfs_return_cluster_to_free_space+0x9e/0xb0 [<ffffffffa702dc37>] ? _raw_spin_unlock+0x27/0x40 [<ffffffffa666a1a1>] find_free_extent+0xba1/0x1520 Andrey noticed this was because we were doing list_first_entry on a list that might be empty. Rework the tests a bit so we don't do that. Signed-off-by: Chris Mason <clm@fb.com> Reprorted-by: Andrey Ryabinin <ryabinin.a.a@gmail.com> Reported-by: Dave Jones <dsj@fb.com>
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When a43eec3 ("bpf: introduce bpf_perf_event_output() helper") added PERF_COUNT_SW_BPF_OUTPUT we ended up with a new entry in the event_symbols_sw array that wasn't initialized, thus set to NULL, fix print_symbol_events() to check for that case so that we don't crash if this happens again. (gdb) bt #0 __match_glob (ignore_space=false, pat=<optimized out>, str=<optimized out>) at util/string.c:198 #1 strglobmatch (str=<optimized out>, pat=pat@entry=0x7fffffffe61d "stall") at util/string.c:252 #2 0x00000000004993a5 in print_symbol_events (type=1, syms=0x872880 <event_symbols_sw+160>, max=11, name_only=false, event_glob=0x7fffffffe61d "stall") at util/parse-events.c:1615 #3 print_events (event_glob=event_glob@entry=0x7fffffffe61d "stall", name_only=false) at util/parse-events.c:1675 #4 0x000000000042c79e in cmd_list (argc=1, argv=0x7fffffffe390, prefix=<optimized out>) at builtin-list.c:68 #5 0x00000000004788a5 in run_builtin (p=p@entry=0x871758 <commands+120>, argc=argc@entry=2, argv=argv@entry=0x7fffffffe390) at perf.c:370 #6 0x0000000000420ab0 in handle_internal_command (argv=0x7fffffffe390, argc=2) at perf.c:429 #7 run_argv (argv=0x7fffffffe110, argcp=0x7fffffffe11c) at perf.c:473 #8 main (argc=2, argv=0x7fffffffe390) at perf.c:588 (gdb) p event_symbols_sw[PERF_COUNT_SW_BPF_OUTPUT] $4 = {symbol = 0x0, alias = 0x0} (gdb) A patch to robustify perf to not segfault when the next counter gets added in the kernel will follow this one. Reported-by: Ingo Molnar <mingo@kernel.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: David Ahern <dsahern@gmail.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/n/tip-57wysblcjfrseb0zg5u7ek10@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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The commit c31df25 ("md/raid10: make sync_request_write() call bio_copy_data()") replaced manual data copying with bio_copy_data() but it doesn't work as intended. The source bio (fbio) is already processed, so its bvec_iter has bi_size == 0 and bi_idx == bi_vcnt. Because of this, bio_copy_data() either does not copy anything, or worse, copies data from the ->bi_next bio if it is set. This causes wrong data to be written to drives during resync and sometimes lockups/crashes in bio_copy_data(): [ 517.338478] NMI watchdog: BUG: soft lockup - CPU#0 stuck for 22s! [md126_raid10:3319] [ 517.347324] Modules linked in: raid10 xt_CHECKSUM ipt_MASQUERADE nf_nat_masquerade_ipv4 tun ip6t_rpfilter ip6t_REJECT nf_reject_ipv6 ipt_REJECT nf_reject_ipv4 xt_conntrack ebtable_nat ebtable_broute bridge stp llc ebtable_filter ebtables ip6table_nat nf_conntrack_ipv6 nf_defrag_ipv6 nf_nat_ipv6 ip6table_mangle ip6table_security ip6table_raw ip6table_filter ip6_tables iptable_nat nf_conntrack_ipv4 nf_defrag_ipv4 nf_nat_ipv4 nf_nat nf_conntrack iptable_mangle iptable_security iptable_raw iptable_filter ip_tables x86_pkg_temp_thermal coretemp kvm_intel kvm crct10dif_pclmul crc32_pclmul cryptd shpchp pcspkr ipmi_si ipmi_msghandler tpm_crb acpi_power_meter acpi_cpufreq ext4 mbcache jbd2 sr_mod cdrom sd_mod e1000e ax88179_178a usbnet mii ahci ata_generic crc32c_intel libahci ptp pata_acpi libata pps_core wmi sunrpc dm_mirror dm_region_hash dm_log dm_mod [ 517.440555] CPU: 0 PID: 3319 Comm: md126_raid10 Not tainted 4.3.0-rc6+ #1 [ 517.448384] Hardware name: Intel Corporation PURLEY/PURLEY, BIOS PLYDCRB1.86B.0055.D14.1509221924 09/22/2015 [ 517.459768] task: ffff880153773980 ti: ffff880150df8000 task.ti: ffff880150df8000 [ 517.468529] RIP: 0010:[<ffffffff812e1888>] [<ffffffff812e1888>] bio_copy_data+0xc8/0x3c0 [ 517.478164] RSP: 0018:ffff880150dfbc98 EFLAGS: 00000246 [ 517.484341] RAX: ffff880169356688 RBX: 0000000000001000 RCX: 0000000000000000 [ 517.492558] RDX: 0000000000000000 RSI: ffffea0001ac2980 RDI: ffffea0000d835c0 [ 517.500773] RBP: ffff880150dfbd08 R08: 0000000000000001 R09: ffff880153773980 [ 517.508987] R10: ffff880169356600 R11: 0000000000001000 R12: 0000000000010000 [ 517.517199] R13: 000000000000e000 R14: 0000000000000000 R15: 0000000000001000 [ 517.525412] FS: 0000000000000000(0000) GS:ffff880174a00000(0000) knlGS:0000000000000000 [ 517.534844] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 517.541507] CR2: 00007f8a044d5fed CR3: 0000000169504000 CR4: 00000000001406f0 [ 517.549722] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 517.557929] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 517.566144] Stack: [ 517.568626] ffff880174a16bc0 ffff880153773980 ffff880169356600 0000000000000000 [ 517.577659] 0000000000000001 0000000000000001 ffff880153773980 ffff88016a61a800 [ 517.586715] ffff880150dfbcf8 0000000000000001 ffff88016dd209e0 0000000000001000 [ 517.595773] Call Trace: [ 517.598747] [<ffffffffa043ef95>] raid10d+0xfc5/0x1690 [raid10] [ 517.605610] [<ffffffff816697ae>] ? __schedule+0x29e/0x8e2 [ 517.611987] [<ffffffff814ff206>] md_thread+0x106/0x140 [ 517.618072] [<ffffffff810c1d80>] ? wait_woken+0x80/0x80 [ 517.624252] [<ffffffff814ff100>] ? super_1_load+0x520/0x520 [ 517.630817] [<ffffffff8109ef89>] kthread+0xc9/0xe0 [ 517.636506] [<ffffffff8109eec0>] ? flush_kthread_worker+0x70/0x70 [ 517.643653] [<ffffffff8166d99f>] ret_from_fork+0x3f/0x70 [ 517.649929] [<ffffffff8109eec0>] ? flush_kthread_worker+0x70/0x70 Signed-off-by: Artur Paszkiewicz <artur.paszkiewicz@intel.com> Reviewed-by: Shaohua Li <shli@kernel.org> Cc: stable@vger.kernel.org (v4.2+) Fixes: c31df25 ("md/raid10: make sync_request_write() call bio_copy_data()") Signed-off-by: NeilBrown <neilb@suse.com>
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The patch c7bfced committed to 4.4-rc causes crash in LVM test shell/lvchange-raid.sh. The kernel crashes with this BUG, the reason is that we attempt to suspend a device that is already suspended. See also https://bugzilla.redhat.com/show_bug.cgi?id=1283491 This patch fixes the bug by changing functions mddev_suspend and mddev_resume to always nest. The number of nested calls to mddev_nested_suspend is kept in the variable mddev->suspended. [neilb: made mddev_suspend() always nest instead of introduce mddev_nested_suspend] kernel BUG at drivers/md/md.c:317! CPU: 3 PID: 32754 Comm: lvm Not tainted 4.4.0-rc2 #1 task: 0000000047076040 ti: 0000000047014000 task.ti: 0000000047014000 YZrvWESTHLNXBCVMcbcbcbcbOGFRQPDI PSW: 00001000000001000000000000001111 Not tainted r00-03 000000000804000f 00000000102c5280 0000000010c7522c 000000007e3d1810 r04-07 0000000010c6f000 000000004ef37f20 000000007e3d1dd0 000000007e3d1810 r08-11 000000007c9f1600 0000000000000000 0000000000000001 ffffffffffffffff r12-15 0000000010c1d000 0000000000000041 00000000f98d63c8 00000000f98e49e4 r16-19 00000000f98e49e4 00000000c138fd06 00000000f98d63c8 0000000000000001 r20-23 0000000000000002 000000004ef37f00 00000000000000b0 00000000000001d1 r24-27 00000000424783a0 000000007e3d1dd0 000000007e3d1810 00000000102b2000 r28-31 0000000000000001 0000000047014840 0000000047014930 0000000000000001 sr00-03 0000000007040800 0000000000000000 0000000000000000 0000000007040800 sr04-07 0000000000000000 0000000000000000 0000000000000000 0000000000000000 IASQ: 0000000000000000 0000000000000000 IAOQ: 00000000102c538c 00000000102c5390 IIR: 03ffe01f ISR: 0000000000000000 IOR: 00000000102b2748 CPU: 3 CR30: 0000000047014000 CR31: 0000000000000000 ORIG_R28: 00000000000000b0 IAOQ[0]: mddev_suspend+0x10c/0x160 [md_mod] IAOQ[1]: mddev_suspend+0x110/0x160 [md_mod] RP(r2): raid1_add_disk+0xd4/0x2c0 [raid1] Backtrace: [<0000000010c7522c>] raid1_add_disk+0xd4/0x2c0 [raid1] [<0000000010c20078>] raid_resume+0x390/0x418 [dm_raid] [<00000000105833e8>] dm_table_resume_targets+0xc0/0x188 [dm_mod] [<000000001057f784>] dm_resume+0x144/0x1e0 [dm_mod] [<0000000010587dd4>] dev_suspend+0x1e4/0x568 [dm_mod] [<0000000010589278>] ctl_ioctl+0x1e8/0x428 [dm_mod] [<0000000010589518>] dm_compat_ctl_ioctl+0x18/0x68 [dm_mod] [<0000000040377b88>] compat_SyS_ioctl+0xd0/0x1558 Fixes: c7bfced ("md: suspend i/o during runtime blk_integrity_unregister") Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: NeilBrown <neilb@suse.com>
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Commit 4f65636 ("Move locks API users to locks_lock_inode_wait()") move flock/posix lock indentify code to locks_lock_inode_wait(), but missed to set fl_flags to FL_FLOCK which caused the following kernel panic on 4.4.0_rc5. kernel BUG at fs/locks.c:1895! invalid opcode: 0000 [#1] SMP Modules linked in: ocfs2(O) ocfs2_dlmfs(O) ocfs2_stack_o2cb(O) ocfs2_dlm(O) ocfs2_nodemanager(O) ocfs2_stackglue(O) iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi xen_kbdfront xen_netfront xen_fbfront xen_blkfront CPU: 0 PID: 20268 Comm: flock_unit_test Tainted: G O 4.4.0-rc5-next-20151217 #1 Hardware name: Xen HVM domU, BIOS 4.3.1OVM 05/14/2014 task: ffff88007b3672c0 ti: ffff880028b58000 task.ti: ffff880028b58000 RIP: locks_lock_inode_wait+0x2e/0x160 Call Trace: ocfs2_do_flock+0x91/0x160 [ocfs2] ocfs2_flock+0x76/0xd0 [ocfs2] SyS_flock+0x10f/0x1a0 entry_SYSCALL_64_fastpath+0x12/0x71 Code: e5 41 57 41 56 49 89 fe 41 55 41 54 53 48 89 f3 48 81 ec 88 00 00 00 8b 46 40 83 e0 03 83 f8 01 0f 84 ad 00 00 00 83 f8 02 74 04 <0f> 0b eb fe 4c 8d ad 60 ff ff ff 4c 8d 7b 58 e8 0e 8e 73 00 4d RIP locks_lock_inode_wait+0x2e/0x160 RSP <ffff880028b5bce8> ---[ end trace dfca74ec9b5b274c ]--- Fixes: 4f65636 ("Move locks API users to locks_lock_inode_wait()") Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com> Cc: Mark Fasheh <mfasheh@suse.de> Cc: Joel Becker <jlbec@evilplan.org> Cc: Joseph Qi <joseph.qi@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Jan 25, 2016
When we do cat /sys/kernel/debug/tracing/printk_formats, we hit kernel panic at t_show. general protection fault: 0000 [#1] PREEMPT SMP CPU: 0 PID: 2957 Comm: sh Tainted: G W O 3.14.55-x86_64-01062-gd4acdc7 #2 RIP: 0010:[<ffffffff811375b2>] [<ffffffff811375b2>] t_show+0x22/0xe0 RSP: 0000:ffff88002b4ebe80 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000004 RDX: 0000000000000004 RSI: ffffffff81fd26a6 RDI: ffff880032f9f7b1 RBP: ffff88002b4ebe98 R08: 0000000000001000 R09: 000000000000ffec R10: 0000000000000000 R11: 000000000000000f R12: ffff880004d9b6c0 R13: 7365725f6d706400 R14: ffff880004d9b6c0 R15: ffffffff82020570 FS: 0000000000000000(0000) GS:ffff88003aa00000(0063) knlGS:00000000f776bc40 CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 CR2: 00000000f6c02ff0 CR3: 000000002c2b3000 CR4: 00000000001007f0 Call Trace: [<ffffffff811dc076>] seq_read+0x2f6/0x3e0 [<ffffffff811b749b>] vfs_read+0x9b/0x160 [<ffffffff811b7f69>] SyS_read+0x49/0xb0 [<ffffffff81a3a4b9>] ia32_do_call+0x13/0x13 ---[ end trace 5bd9eb630614861e ]--- Kernel panic - not syncing: Fatal exception When the first time find_next calls find_next_mod_format, it should iterate the trace_bprintk_fmt_list to find the first print format of the module. However in current code, start_index is smaller than *pos at first, and code will not iterate the list. Latter container_of will get the wrong address with former v, which will cause mod_fmt be a meaningless object and so is the returned mod_fmt->fmt. This patch will fix it by correcting the start_index. After fixed, when the first time calls find_next_mod_format, start_index will be equal to *pos, and code will iterate the trace_bprintk_fmt_list to get the right module printk format, so is the returned mod_fmt->fmt. Link: http://lkml.kernel.org/r/5684B900.9000309@intel.com Cc: stable@vger.kernel.org # 3.12+ Fixes: 102c932 "tracing: Add __tracepoint_string() to export string pointers" Signed-off-by: Qiu Peiyang <peiyangx.qiu@intel.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
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This reverts commit 87b5ed8 ("ASoC: Intel: Skylake: fix memory leak") as it causes regression on Skylake devices The SKL drivers can be deferred probe. The topology file based widgets can have references to topology file so this can't be freed until card is fully created, so revert this patch for now [ 66.682767] BUG: unable to handle kernel paging request at ffffc900001363fc [ 66.690735] IP: [<ffffffff806c94dd>] strnlen+0xd/0x40 [ 66.696509] PGD 16e035067 PUD 16e036067 PMD 16e038067 PTE 0 [ 66.702925] Oops: 0000 [#1] PREEMPT SMP [ 66.768390] CPU: 3 PID: 57 Comm: kworker/u16:3 Tainted: G O 4.4.0-rc7-skl #62 [ 66.778869] Hardware name: Intel Corporation Skylake Client platform [ 66.793201] Workqueue: deferwq deferred_probe_work_func [ 66.799173] task: ffff88008b700f40 ti: ffff88008b704000 task.ti: ffff88008b704000 [ 66.807692] RIP: 0010:[<ffffffff806c94dd>] [<ffffffff806c94dd>] strnlen+0xd/0x40 [ 66.816243] RSP: 0018:ffff88008b707878 EFLAGS: 00010286 [ 66.822293] RAX: ffffffff80e60a82 RBX: 000000000000000e RCX: fffffffffffffffe [ 66.830406] RDX: ffffc900001363fc RSI: ffffffffffffffff RDI: ffffc900001363fc [ 66.838520] RBP: ffff88008b707878 R08: 000000000000ffff R09: 000000000000ffff [ 66.846649] R10: 0000000000000001 R11: ffffffffa01c6368 R12: ffffc900001363fc [ 66.854765] R13: 0000000000000000 R14: 00000000ffffffff R15: 0000000000000000 [ 66.862910] FS: 0000000000000000(0000) GS:ffff88016ecc0000(0000) knlGS:0000000000000000 [ 66.872150] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 66.878696] CR2: ffffc900001363fc CR3: 0000000002c09000 CR4: 00000000003406e0 [ 66.886820] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 66.894938] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 66.903052] Stack: [ 66.905346] ffff88008b7078b0 ffffffff806cb1db 000000000000000e 0000000000000000 [ 66.913854] ffff88008b707928 ffffffffa00d1050 ffffffffa00d104e ffff88008b707918 [ 66.922353] ffffffff806ccbd6 ffff88008b707948 0000000000000046 ffff88008b707940 [ 66.930855] Call Trace: [ 66.933646] [<ffffffff806cb1db>] string.isra.4+0x3b/0xd0 [ 66.939793] [<ffffffff806ccbd6>] vsnprintf+0x116/0x540 [ 66.945742] [<ffffffff806d02f0>] kvasprintf+0x40/0x80 [ 66.951591] [<ffffffff806d0370>] kasprintf+0x40/0x50 [ 66.957359] [<ffffffffa00c085f>] dapm_create_or_share_kcontrol+0x1cf/0x300 [snd_soc_core] [ 66.966771] [<ffffffff8057dd1e>] ? __kmalloc+0x16e/0x2a0 [ 66.972931] [<ffffffffa00c0dab>] snd_soc_dapm_new_widgets+0x41b/0x4b0 [snd_soc_core] [ 66.981857] [<ffffffffa00be8c0>] ? snd_soc_dapm_add_routes+0xb0/0xd0 [snd_soc_core] [ 67.007828] [<ffffffffa00b92ed>] soc_probe_component+0x23d/0x360 [snd_soc_core] [ 67.016244] [<ffffffff80b14e69>] ? mutex_unlock+0x9/0x10 [ 67.022405] [<ffffffffa00ba02f>] snd_soc_instantiate_card+0x47f/0xd10 [snd_soc_core] [ 67.031329] [<ffffffff8049eeb2>] ? debug_mutex_init+0x32/0x40 [ 67.037973] [<ffffffffa00baa92>] snd_soc_register_card+0x1d2/0x2b0 [snd_soc_core] [ 67.046619] [<ffffffffa00c8b54>] devm_snd_soc_register_card+0x44/0x80 [snd_soc_core] [ 67.055539] [<ffffffffa01c303b>] skylake_audio_probe+0x1b/0x20 [snd_soc_skl_rt286] [ 67.064292] [<ffffffff808aa887>] platform_drv_probe+0x37/0x90 Signed-off-by: Vinod Koul <vinod.koul@intel.com> Signed-off-by: Mark Brown <broonie@kernel.org>
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Jan 25, 2016
kernel test robot has reported the following crash: BUG: unable to handle kernel NULL pointer dereference at 00000100 IP: [<c1074df6>] __queue_work+0x26/0x390 *pdpt = 0000000000000000 *pde = f000ff53f000ff53 *pde = f000ff53f000ff53 Oops: 0000 [#1] PREEMPT PREEMPT SMP SMP CPU: 0 PID: 24 Comm: kworker/0:1 Not tainted 4.4.0-rc4-00139-g373ccbe #1 Workqueue: events vmstat_shepherd task: cb684600 ti: cb7ba000 task.ti: cb7ba000 EIP: 0060:[<c1074df6>] EFLAGS: 00010046 CPU: 0 EIP is at __queue_work+0x26/0x390 EAX: 00000046 EBX: cbb37800 ECX: cbb37800 EDX: 00000000 ESI: 00000000 EDI: 00000000 EBP: cb7bbe68 ESP: cb7bbe38 DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068 CR0: 8005003b CR2: 00000100 CR3: 01fd5000 CR4: 000006b0 Stack: Call Trace: __queue_delayed_work+0xa1/0x160 queue_delayed_work_on+0x36/0x60 vmstat_shepherd+0xad/0xf0 process_one_work+0x1aa/0x4c0 worker_thread+0x41/0x440 kthread+0xb0/0xd0 ret_from_kernel_thread+0x21/0x40 The reason is that start_shepherd_timer schedules the shepherd work item which uses vmstat_wq (vmstat_shepherd) before setup_vmstat allocates that workqueue so if the further initialization takes more than HZ we might end up scheduling on a NULL vmstat_wq. This is really unlikely but not impossible. Fixes: 373ccbe ("mm, vmstat: allow WQ concurrency to discover memory reclaim doesn't make any progress") Reported-by: kernel test robot <ying.huang@linux.intel.com> Signed-off-by: Michal Hocko <mhocko@suse.com> Tested-by: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp> Cc: stable@vger.kernel.org Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Feb 2, 2016
ib_send_cm_drep() calls cm_enter_timewait() while holding a spinlock that can be locked from inside an interrupt handler. Hence do not enable interrupts inside cm_enter_timewait() if called with interrupts disabled. This patch fixes e.g. the following deadlock: Acked-by: Erez Shitrit <erezsh@mellanox.com> ================================= [ INFO: inconsistent lock state ] 4.4.0-rc7+ #1 Tainted: G E --------------------------------- inconsistent {HARDIRQ-ON-W} -> {IN-HARDIRQ-W} usage. swapper/8/0 [HC1[1]:SC0[0]:HE0:SE1] takes: (&(&cm_id_priv->lock)->rlock){?.+...}, at: [<ffffffffa036eec4>] cm_establish+0x 74/0x1b0 [ib_cm] {HARDIRQ-ON-W} state was registered at: [<ffffffff810a3c11>] mark_held_locks+0x71/0x90 [<ffffffff810a3e87>] trace_hardirqs_on_caller+0xa7/0x1c0 [<ffffffff810a3fad>] trace_hardirqs_on+0xd/0x10 [<ffffffff8151c40b>] _raw_spin_unlock_irq+0x2b/0x40 [<ffffffffa036ea8e>] cm_enter_timewait+0xae/0x100 [ib_cm] [<ffffffffa036ff76>] ib_send_cm_drep+0xb6/0x190 [ib_cm] [<ffffffffa052ed08>] srp_cm_handler+0x128/0x1a0 [ib_srp] [<ffffffffa0370340>] cm_process_work+0x20/0xf0 [ib_cm] [<ffffffffa0371335>] cm_dreq_handler+0x135/0x2c0 [ib_cm] [<ffffffffa03733c5>] cm_work_handler+0x75/0xd0 [ib_cm] [<ffffffff8107184d>] process_one_work+0x1bd/0x460 [<ffffffff81073148>] worker_thread+0x118/0x420 [<ffffffff81078454>] kthread+0xe4/0x100 [<ffffffff8151cbbf>] ret_from_fork+0x3f/0x70 irq event stamp: 1672286 hardirqs last enabled at (1672283): [<ffffffff81408ec0>] poll_idle+0x10/0x80 hardirqs last disabled at (1672284): [<ffffffff8151d304>] common_interrupt+0x84/0x89 softirqs last enabled at (1672286): [<ffffffff8105b4dc>] _local_bh_enable+0x1c/0x50 softirqs last disabled at (1672285): [<ffffffff8105b697>] irq_enter+0x47/0x70 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&(&cm_id_priv->lock)->rlock); <Interrupt> lock(&(&cm_id_priv->lock)->rlock); *** DEADLOCK *** no locks held by swapper/8/0. stack backtrace: CPU: 8 PID: 0 Comm: swapper/8 Tainted: G E 4.4.0-rc7+ #1 Hardware name: Dell Inc. PowerEdge R430/03XKDV, BIOS 1.0.2 11/17/2014 ffff88045af5e950 ffff88046e503a88 ffffffff81251c1b 0000000000000007 0000000000000006 0000000000000003 ffff88045af5ddc0 ffff88046e503ad8 ffffffff810a32f4 0000000000000000 0000000000000000 0000000000000001 Call Trace: <IRQ> [<ffffffff81251c1b>] dump_stack+0x4f/0x74 [<ffffffff810a32f4>] print_usage_bug+0x184/0x190 [<ffffffff810a36e2>] mark_lock_irq+0xf2/0x290 [<ffffffff810a3995>] mark_lock+0x115/0x1b0 [<ffffffff810a3b8c>] mark_irqflags+0x15c/0x170 [<ffffffff810a4fef>] __lock_acquire+0x1ef/0x560 [<ffffffff810a53c2>] lock_acquire+0x62/0x80 [<ffffffff8151bd33>] _raw_spin_lock_irqsave+0x43/0x60 [<ffffffffa036eec4>] cm_establish+0x74/0x1b0 [ib_cm] [<ffffffffa036f031>] ib_cm_notify+0x31/0x100 [ib_cm] [<ffffffffa0637f24>] srpt_qp_event+0x54/0xd0 [ib_srpt] [<ffffffffa0196052>] mlx4_ib_qp_event+0x72/0xc0 [mlx4_ib] [<ffffffffa00775b9>] mlx4_qp_event+0x69/0xd0 [mlx4_core] [<ffffffffa006000e>] mlx4_eq_int+0x51e/0xd50 [mlx4_core] [<ffffffffa006084f>] mlx4_msi_x_interrupt+0xf/0x20 [mlx4_core] [<ffffffff810b67b0>] handle_irq_event_percpu+0x40/0x110 [<ffffffff810b68bf>] handle_irq_event+0x3f/0x70 [<ffffffff810ba7f9>] handle_edge_irq+0x79/0x120 [<ffffffff81007f3d>] handle_irq+0x5d/0x130 [<ffffffff810071fd>] do_IRQ+0x6d/0x130 [<ffffffff8151d309>] common_interrupt+0x89/0x89 <EOI> [<ffffffff8140895f>] cpuidle_enter_state+0xcf/0x200 [<ffffffff81408aa2>] cpuidle_enter+0x12/0x20 [<ffffffff810990d6>] call_cpuidle+0x36/0x60 [<ffffffff81099163>] cpuidle_idle_call+0x63/0x110 [<ffffffff8109930a>] cpu_idle_loop+0xfa/0x130 [<ffffffff8109934e>] cpu_startup_entry+0xe/0x10 [<ffffffff8103c443>] start_secondary+0x83/0x90 Fixes: commit be4b499 ("IB/cm: Do not queue work to a device that's going away") Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com> Cc: Erez Shitrit <erezsh@mellanox.com> Cc: stable <stable@vger.kernel.org> Signed-off-by: Doug Ledford <dledford@redhat.com>
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While running a stress test I ran into a deadlock when running the delayed iputs at transaction time, which produced the following report and trace: [ 886.399989] ============================================= [ 886.400871] [ INFO: possible recursive locking detected ] [ 886.401663] 4.4.0-rc6-btrfs-next-18+ #1 Not tainted [ 886.402384] --------------------------------------------- [ 886.403182] fio/8277 is trying to acquire lock: [ 886.403568] (&fs_info->delayed_iput_sem){++++..}, at: [<ffffffffa0538823>] btrfs_run_delayed_iputs+0x36/0xbf [btrfs] [ 886.403568] [ 886.403568] but task is already holding lock: [ 886.403568] (&fs_info->delayed_iput_sem){++++..}, at: [<ffffffffa0538823>] btrfs_run_delayed_iputs+0x36/0xbf [btrfs] [ 886.403568] [ 886.403568] other info that might help us debug this: [ 886.403568] Possible unsafe locking scenario: [ 886.403568] [ 886.403568] CPU0 [ 886.403568] ---- [ 886.403568] lock(&fs_info->delayed_iput_sem); [ 886.403568] lock(&fs_info->delayed_iput_sem); [ 886.403568] [ 886.403568] *** DEADLOCK *** [ 886.403568] [ 886.403568] May be due to missing lock nesting notation [ 886.403568] [ 886.403568] 3 locks held by fio/8277: [ 886.403568] #0: (sb_writers#11){.+.+.+}, at: [<ffffffff81174c4c>] __sb_start_write+0x5f/0xb0 [ 886.403568] #1: (&sb->s_type->i_mutex_key#15){+.+.+.}, at: [<ffffffffa054620d>] btrfs_file_write_iter+0x73/0x408 [btrfs] [ 886.403568] #2: (&fs_info->delayed_iput_sem){++++..}, at: [<ffffffffa0538823>] btrfs_run_delayed_iputs+0x36/0xbf [btrfs] [ 886.403568] [ 886.403568] stack backtrace: [ 886.403568] CPU: 6 PID: 8277 Comm: fio Not tainted 4.4.0-rc6-btrfs-next-18+ #1 [ 886.403568] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS by qemu-project.org 04/01/2014 [ 886.403568] 0000000000000000 ffff88009f80f770 ffffffff8125d4fd ffffffff82af1fc0 [ 886.403568] ffff88009f80f830 ffffffff8108e5f9 0000000200000000 ffff88009fd92290 [ 886.403568] 0000000000000000 ffffffff82af1fc0 ffffffff829cfb01 00042b216d008804 [ 886.403568] Call Trace: [ 886.403568] [<ffffffff8125d4fd>] dump_stack+0x4e/0x79 [ 886.403568] [<ffffffff8108e5f9>] __lock_acquire+0xd42/0xf0b [ 886.403568] [<ffffffff810c22db>] ? __module_address+0xdf/0x108 [ 886.403568] [<ffffffff8108eb77>] lock_acquire+0x10d/0x194 [ 886.403568] [<ffffffff8108eb77>] ? lock_acquire+0x10d/0x194 [ 886.403568] [<ffffffffa0538823>] ? btrfs_run_delayed_iputs+0x36/0xbf [btrfs] [ 886.489542] [<ffffffff8148556b>] down_read+0x3e/0x4d [ 886.489542] [<ffffffffa0538823>] ? btrfs_run_delayed_iputs+0x36/0xbf [btrfs] [ 886.489542] [<ffffffffa0538823>] btrfs_run_delayed_iputs+0x36/0xbf [btrfs] [ 886.489542] [<ffffffffa0533953>] btrfs_commit_transaction+0x8f5/0x96e [btrfs] [ 886.489542] [<ffffffffa0521d7a>] flush_space+0x435/0x44a [btrfs] [ 886.489542] [<ffffffffa052218b>] ? reserve_metadata_bytes+0x26a/0x384 [btrfs] [ 886.489542] [<ffffffffa05221ae>] reserve_metadata_bytes+0x28d/0x384 [btrfs] [ 886.489542] [<ffffffffa052256c>] ? btrfs_block_rsv_refill+0x58/0x96 [btrfs] [ 886.489542] [<ffffffffa0522584>] btrfs_block_rsv_refill+0x70/0x96 [btrfs] [ 886.489542] [<ffffffffa053d747>] btrfs_evict_inode+0x394/0x55a [btrfs] [ 886.489542] [<ffffffff81188e31>] evict+0xa7/0x15c [ 886.489542] [<ffffffff81189878>] iput+0x1d3/0x266 [ 886.489542] [<ffffffffa053887c>] btrfs_run_delayed_iputs+0x8f/0xbf [btrfs] [ 886.489542] [<ffffffffa0533953>] btrfs_commit_transaction+0x8f5/0x96e [btrfs] [ 886.489542] [<ffffffff81085096>] ? signal_pending_state+0x31/0x31 [ 886.489542] [<ffffffffa0521191>] btrfs_alloc_data_chunk_ondemand+0x1d7/0x288 [btrfs] [ 886.489542] [<ffffffffa0521282>] btrfs_check_data_free_space+0x40/0x59 [btrfs] [ 886.489542] [<ffffffffa05228f5>] btrfs_delalloc_reserve_space+0x1e/0x4e [btrfs] [ 886.489542] [<ffffffffa053620a>] btrfs_direct_IO+0x10c/0x27e [btrfs] [ 886.489542] [<ffffffff8111d9a1>] generic_file_direct_write+0xb3/0x128 [ 886.489542] [<ffffffffa05463c3>] btrfs_file_write_iter+0x229/0x408 [btrfs] [ 886.489542] [<ffffffff8108ae38>] ? __lock_is_held+0x38/0x50 [ 886.489542] [<ffffffff8117279e>] __vfs_write+0x7c/0xa5 [ 886.489542] [<ffffffff81172cda>] vfs_write+0xa0/0xe4 [ 886.489542] [<ffffffff811734cc>] SyS_write+0x50/0x7e [ 886.489542] [<ffffffff814872d7>] entry_SYSCALL_64_fastpath+0x12/0x6f [ 1081.852335] INFO: task fio:8244 blocked for more than 120 seconds. [ 1081.854348] Not tainted 4.4.0-rc6-btrfs-next-18+ #1 [ 1081.857560] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 1081.863227] fio D ffff880213f9bb28 0 8244 8240 0x00000000 [ 1081.868719] ffff880213f9bb28 00ffffff810fc6b0 ffffffff0000000a ffff88023ed55240 [ 1081.872499] ffff880206b5d400 ffff880213f9c000 ffff88020a4d5318 ffff880206b5d400 [ 1081.876834] ffffffff00000001 ffff880206b5d400 ffff880213f9bb40 ffffffff81482ba4 [ 1081.880782] Call Trace: [ 1081.881793] [<ffffffff81482ba4>] schedule+0x7f/0x97 [ 1081.883340] [<ffffffff81485eb5>] rwsem_down_write_failed+0x2d5/0x325 [ 1081.895525] [<ffffffff8108d48d>] ? trace_hardirqs_on_caller+0x16/0x1ab [ 1081.897419] [<ffffffff81269723>] call_rwsem_down_write_failed+0x13/0x20 [ 1081.899251] [<ffffffff81269723>] ? call_rwsem_down_write_failed+0x13/0x20 [ 1081.901063] [<ffffffff81089fae>] ? __down_write_nested.isra.0+0x1f/0x21 [ 1081.902365] [<ffffffff814855bd>] down_write+0x43/0x57 [ 1081.903846] [<ffffffffa05211b0>] ? btrfs_alloc_data_chunk_ondemand+0x1f6/0x288 [btrfs] [ 1081.906078] [<ffffffffa05211b0>] btrfs_alloc_data_chunk_ondemand+0x1f6/0x288 [btrfs] [ 1081.908846] [<ffffffff8108d461>] ? mark_held_locks+0x56/0x6c [ 1081.910409] [<ffffffffa0521282>] btrfs_check_data_free_space+0x40/0x59 [btrfs] [ 1081.912482] [<ffffffffa05228f5>] btrfs_delalloc_reserve_space+0x1e/0x4e [btrfs] [ 1081.914597] [<ffffffffa053620a>] btrfs_direct_IO+0x10c/0x27e [btrfs] [ 1081.919037] [<ffffffff8111d9a1>] generic_file_direct_write+0xb3/0x128 [ 1081.920754] [<ffffffffa05463c3>] btrfs_file_write_iter+0x229/0x408 [btrfs] [ 1081.922496] [<ffffffff8108ae38>] ? __lock_is_held+0x38/0x50 [ 1081.923922] [<ffffffff8117279e>] __vfs_write+0x7c/0xa5 [ 1081.925275] [<ffffffff81172cda>] vfs_write+0xa0/0xe4 [ 1081.926584] [<ffffffff811734cc>] SyS_write+0x50/0x7e [ 1081.927968] [<ffffffff814872d7>] entry_SYSCALL_64_fastpath+0x12/0x6f [ 1081.985293] INFO: lockdep is turned off. [ 1081.986132] INFO: task fio:8249 blocked for more than 120 seconds. [ 1081.987434] Not tainted 4.4.0-rc6-btrfs-next-18+ #1 [ 1081.988534] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 1081.990147] fio D ffff880218febbb8 0 8249 8240 0x00000000 [ 1081.991626] ffff880218febbb8 00ffffff81486b8e ffff88020000000b ffff88023ed75240 [ 1081.993258] ffff8802120a9a00 ffff880218fec000 ffff88020a4d5318 ffff8802120a9a00 [ 1081.994850] ffffffff00000001 ffff8802120a9a00 ffff880218febbd0 ffffffff81482ba4 [ 1081.996485] Call Trace: [ 1081.997037] [<ffffffff81482ba4>] schedule+0x7f/0x97 [ 1081.998017] [<ffffffff81485eb5>] rwsem_down_write_failed+0x2d5/0x325 [ 1081.999241] [<ffffffff810852a5>] ? finish_wait+0x6d/0x76 [ 1082.000306] [<ffffffff81269723>] call_rwsem_down_write_failed+0x13/0x20 [ 1082.001533] [<ffffffff81269723>] ? call_rwsem_down_write_failed+0x13/0x20 [ 1082.002776] [<ffffffff81089fae>] ? __down_write_nested.isra.0+0x1f/0x21 [ 1082.003995] [<ffffffff814855bd>] down_write+0x43/0x57 [ 1082.005000] [<ffffffffa05211b0>] ? btrfs_alloc_data_chunk_ondemand+0x1f6/0x288 [btrfs] [ 1082.007403] [<ffffffffa05211b0>] btrfs_alloc_data_chunk_ondemand+0x1f6/0x288 [btrfs] [ 1082.008988] [<ffffffffa0545064>] btrfs_fallocate+0x7c1/0xc2f [btrfs] [ 1082.010193] [<ffffffff8108a1ba>] ? percpu_down_read+0x4e/0x77 [ 1082.011280] [<ffffffff81174c4c>] ? __sb_start_write+0x5f/0xb0 [ 1082.012265] [<ffffffff81174c4c>] ? __sb_start_write+0x5f/0xb0 [ 1082.013021] [<ffffffff811712e4>] vfs_fallocate+0x170/0x1ff [ 1082.013738] [<ffffffff81181ebb>] ioctl_preallocate+0x89/0x9b [ 1082.014778] [<ffffffff811822d7>] do_vfs_ioctl+0x40a/0x4ea [ 1082.015778] [<ffffffff81176ea7>] ? SYSC_newfstat+0x25/0x2e [ 1082.016806] [<ffffffff8118b4de>] ? __fget_light+0x4d/0x71 [ 1082.017789] [<ffffffff8118240e>] SyS_ioctl+0x57/0x79 [ 1082.018706] [<ffffffff814872d7>] entry_SYSCALL_64_fastpath+0x12/0x6f This happens because we can recursively acquire the semaphore fs_info->delayed_iput_sem when attempting to allocate space to satisfy a file write request as shown in the first trace above - when committing a transaction we acquire (down_read) the semaphore before running the delayed iputs, and when running a delayed iput() we can end up calling an inode's eviction handler, which in turn commits another transaction and attempts to acquire (down_read) again the semaphore to run more delayed iput operations. This results in a deadlock because if a task acquires multiple times a semaphore it should invoke down_read_nested() with a different lockdep class for each level of recursion. Fix this by simplifying the implementation and use a mutex instead that is acquired by the cleaner kthread before it runs the delayed iputs instead of always acquiring a semaphore before delayed references are run from anywhere. Fixes: d7c1517 (btrfs: Fix NO_SPACE bug caused by delayed-iput) Cc: stable@vger.kernel.org # 4.1+ Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Chris Mason <clm@fb.com>
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An unprivileged user can trigger an oops on a kernel with
CONFIG_CHECKPOINT_RESTORE.
proc_pid_cmdline_read takes mmap_sem for reading and obtains args + env
start/end values. These get sanity checked as follows:
BUG_ON(arg_start > arg_end);
BUG_ON(env_start > env_end);
These can be changed by prctl_set_mm. Turns out also takes the semaphore for
reading, effectively rendering it useless. This results in:
kernel BUG at fs/proc/base.c:240!
invalid opcode: 0000 [#1] SMP
Modules linked in: virtio_net
CPU: 0 PID: 925 Comm: a.out Not tainted 4.4.0-rc8-next-20160105dupa+ #71
Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
task: ffff880077a68000 ti: ffff8800784d0000 task.ti: ffff8800784d0000
RIP: proc_pid_cmdline_read+0x520/0x530
RSP: 0018:ffff8800784d3db8 EFLAGS: 00010206
RAX: ffff880077c5b6b0 RBX: ffff8800784d3f18 RCX: 0000000000000000
RDX: 0000000000000002 RSI: 00007f78e8857000 RDI: 0000000000000246
RBP: ffff8800784d3e40 R08: 0000000000000008 R09: 0000000000000001
R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000050
R13: 00007f78e8857800 R14: ffff88006fcef000 R15: ffff880077c5b600
FS: 00007f78e884a740(0000) GS:ffff88007b200000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: 00007f78e8361770 CR3: 00000000790a5000 CR4: 00000000000006f0
Call Trace:
__vfs_read+0x37/0x100
vfs_read+0x82/0x130
SyS_read+0x58/0xd0
entry_SYSCALL_64_fastpath+0x12/0x76
Code: 4c 8b 7d a8 eb e9 48 8b 9d 78 ff ff ff 4c 8b 7d 90 48 8b 03 48 39 45 a8 0f 87 f0 fe ff ff e9 d1 fe ff ff 4c 8b 7d 90 eb c6 0f 0b <0f> 0b 0f 0b 66 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00
RIP proc_pid_cmdline_read+0x520/0x530
---[ end trace 97882617ae9c6818 ]---
Turns out there are instances where the code just reads aformentioned
values without locking whatsoever - namely environ_read and get_cmdline.
Interestingly these functions look quite resilient against bogus values,
but I don't believe this should be relied upon.
The first patch gets rid of the oops bug by grabbing mmap_sem for
writing.
The second patch is optional and puts locking around aformentioned
consumers for safety. Consumers of other fields don't seem to benefit
from similar treatment and are left untouched.
This patch (of 2):
The code was taking the semaphore for reading, which does not protect
against readers nor concurrent modifications.
The problem could cause a sanity checks to fail in procfs's cmdline
reader, resulting in an OOPS.
Note that some functions perform an unlocked read of various mm fields,
but they seem to be fine despite possible modificaton.
Signed-off-by: Mateusz Guzik <mguzik@redhat.com>
Acked-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Jarod Wilson <jarod@redhat.com>
Cc: Jan Stancek <jstancek@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Anshuman Khandual <anshuman.linux@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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This patch is borrowed from x86 hpet driver and explaind below: Due to the overly intelligent design of HPETs, we need to workaround the problem that the compare value which we write is already behind the actual counter value at the point where the value hits the real compare register. This happens for two reasons: 1) We read out the counter, add the delta and write the result to the compare register. When a NMI hits between the read out and the write then the counter can be ahead of the event already. 2) The write to the compare register is delayed by up to two HPET cycles in AMD chipsets. We can work around this by reading back the compare register to make sure that the written value has hit the hardware. But that is bad performance wise for the normal case where the event is far enough in the future. As we already know that the write can be delayed by up to two cycles we can avoid the read back of the compare register completely if we make the decision whether the delta has elapsed already or not based on the following calculation: cmp = event - actual_count; If cmp is less than 64 HPET clock cycles, then we decide that the event has happened already and return -ETIME. That covers the above #1 and #2 problems which would cause a wait for HPET wraparound (~306 seconds). Signed-off-by: Huacai Chen <chenhc@lemote.com> Cc: Aurelien Jarno <aurelien@aurel32.net> Cc: Steven J. Hill <Steven.Hill@imgtec.com> Cc: Fuxin Zhang <zhangfx@lemote.com> Cc: Zhangjin Wu <wuzhangjin@gmail.com> Cc: Huacai Chen <chenhc@lemote.com> Cc: linux-mips@linux-mips.org Cc: stable@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/12162/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
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This crash is caused by NULL pointer deference, in page_to_pfn() marco, when page == NULL : Unable to handle kernel NULL pointer dereference at virtual address 00000000 Internal error: Oops: 94000006 [#1] SMP Modules linked in: CPU: 1 PID: 26 Comm: khugepaged Tainted: G W 4.3.0-rc6-next-20151022ajb-00001-g32f3386-dirty #3 PC is at khugepaged+0x378/0x1af8 LR is at khugepaged+0x418/0x1af8 Process khugepaged (pid: 26, stack limit = 0xffffffc079638020) Call trace: khugepaged+0x378/0x1af8 kthread+0xdc/0xf4 ret_from_fork+0xc/0x40 Code: 35001700 f0002c60 aa0703e3 f9009fa0 (f94000e0) ---[ end trace 637503d8e28ae69e ]--- Kernel panic - not syncing: Fatal exception CPU2: stopping CPU: 2 PID: 0 Comm: swapper/2 Tainted: G D W 4.3.0-rc6-next-20151022ajb-00001-g32f3386-dirty #3 Hardware name: linux,dummy-virt (DT) [akpm@linux-foundation.org: fix fat-fingered merge resolution] Signed-off-by: yalin wang <yalin.wang2010@gmail.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: David Rientjes <rientjes@google.com> Cc: Cyrill Gorcunov <gorcunov@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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During genpd_poweron, genpd->lock is acquired recursively for each parent (master) domain, which are separate objects. This confuses lockdep, which considers every operation on genpd->lock as being done on the same lock class. This leads to the following false positive warning: ============================================= [ INFO: possible recursive locking detected ] 4.4.0-rc4-xu3s #32 Not tainted --------------------------------------------- swapper/0/1 is trying to acquire lock: (&genpd->lock){+.+...}, at: [<c0361550>] __genpd_poweron+0x64/0x108 but task is already holding lock: (&genpd->lock){+.+...}, at: [<c0361af8>] genpd_dev_pm_attach+0x168/0x1b8 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&genpd->lock); lock(&genpd->lock); *** DEADLOCK *** May be due to missing lock nesting notation 3 locks held by swapper/0/1: #0: (&dev->mutex){......}, at: [<c0350910>] __driver_attach+0x48/0x98 #1: (&dev->mutex){......}, at: [<c0350920>] __driver_attach+0x58/0x98 #2: (&genpd->lock){+.+...}, at: [<c0361af8>] genpd_dev_pm_attach+0x168/0x1b8 stack backtrace: CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.4.0-rc4-xu3s #32 Hardware name: SAMSUNG EXYNOS (Flattened Device Tree) [<c0016c98>] (unwind_backtrace) from [<c00139c4>] (show_stack+0x10/0x14) [<c00139c4>] (show_stack) from [<c0270df0>] (dump_stack+0x84/0xc4) [<c0270df0>] (dump_stack) from [<c00780b8>] (__lock_acquire+0x1f88/0x215c) [<c00780b8>] (__lock_acquire) from [<c007886c>] (lock_acquire+0xa4/0xd0) [<c007886c>] (lock_acquire) from [<c0641f2c>] (mutex_lock_nested+0x70/0x4d4) [<c0641f2c>] (mutex_lock_nested) from [<c0361550>] (__genpd_poweron+0x64/0x108) [<c0361550>] (__genpd_poweron) from [<c0361b00>] (genpd_dev_pm_attach+0x170/0x1b8) [<c0361b00>] (genpd_dev_pm_attach) from [<c03520a8>] (platform_drv_probe+0x2c/0xac) [<c03520a8>] (platform_drv_probe) from [<c03507d4>] (driver_probe_device+0x208/0x2fc) [<c03507d4>] (driver_probe_device) from [<c035095c>] (__driver_attach+0x94/0x98) [<c035095c>] (__driver_attach) from [<c034ec14>] (bus_for_each_dev+0x68/0x9c) [<c034ec14>] (bus_for_each_dev) from [<c034fec8>] (bus_add_driver+0x1a0/0x218) [<c034fec8>] (bus_add_driver) from [<c035115c>] (driver_register+0x78/0xf8) [<c035115c>] (driver_register) from [<c0338488>] (exynos_drm_register_drivers+0x28/0x74) [<c0338488>] (exynos_drm_register_drivers) from [<c0338594>] (exynos_drm_init+0x6c/0xc4) [<c0338594>] (exynos_drm_init) from [<c00097f4>] (do_one_initcall+0x90/0x1dc) [<c00097f4>] (do_one_initcall) from [<c0895e08>] (kernel_init_freeable+0x158/0x1f8) [<c0895e08>] (kernel_init_freeable) from [<c063ecac>] (kernel_init+0x8/0xe8) [<c063ecac>] (kernel_init) from [<c000f7d0>] (ret_from_fork+0x14/0x24) This patch replaces mutex_lock with mutex_lock_nested() and uses recursion depth to annotate each genpd->lock operation with separate lockdep subclass. Reported-by: Anand Moon <linux.amoon@gmail.com> Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Tested-by: Anand Moon <linux.amoon@gmail.com> Tested-by: Tobias Jakobi <tjakobi@math.uni-bielefeld.de> Acked-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
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The fixes provided in this patch assigns a valid net_device structure to skb before dispatching it for further processing. Scenario #1: ============ Bluetooth 6lowpan receives an uncompressed IPv6 header, and dispatches it to netif. The following error occurs: Null pointer dereference error #1 crash log: [ 845.854013] BUG: unable to handle kernel NULL pointer dereference at 0000000000000048 [ 845.855785] IP: [<ffffffff816e3d36>] enqueue_to_backlog+0x56/0x240 ... [ 845.909459] Call Trace: [ 845.911678] [<ffffffff816e3f64>] netif_rx_internal+0x44/0xf0 The first modification fixes the NULL pointer dereference error by assigning dev to the local_skb in order to set a valid net_device before processing the skb by netif_rx_ni(). Scenario #2: ============ Bluetooth 6lowpan receives an UDP compressed message which needs further decompression by nhc_udp. The following error occurs: Null pointer dereference error #2 crash log: [ 63.295149] BUG: unable to handle kernel NULL pointer dereference at 0000000000000840 [ 63.295931] IP: [<ffffffffc0559540>] udp_uncompress+0x320/0x626 [nhc_udp] The second modification fixes the NULL pointer dereference error by assigning dev to the local_skb in the case of a udp compressed packet. The 6lowpan udp_uncompress function expects that the net_device is set in the skb when checking lltype. Signed-off-by: Glenn Ruben Bakke <glenn.ruben.bakke@nordicsemi.no> Signed-off-by: Lukasz Duda <lukasz.duda@nordicsemi.no> Acked-by: Jukka Rissanen <jukka.rissanen@linux.intel.com> Signed-off-by: Johan Hedberg <johan.hedberg@intel.com> Cc: stable@vger.kernel.org # 4.4+
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Calling apply_to_page_range with an empty range results in a BUG_ON from the core code. This can be triggered by trying to load the st_drv module with CONFIG_DEBUG_SET_MODULE_RONX enabled: kernel BUG at mm/memory.c:1874! Internal error: Oops - BUG: 0 [#1] PREEMPT SMP Modules linked in: CPU: 3 PID: 1764 Comm: insmod Not tainted 4.5.0-rc1+ #2 Hardware name: ARM Juno development board (r0) (DT) task: ffffffc9763b8000 ti: ffffffc975af8000 task.ti: ffffffc975af8000 PC is at apply_to_page_range+0x2cc/0x2d0 LR is at change_memory_common+0x80/0x108 This patch fixes the issue by making change_memory_common (called by the set_memory_* functions) a NOP when numpages == 0, therefore avoiding the erroneous call to apply_to_page_range and bringing us into line with x86 and s390. Cc: <stable@vger.kernel.org> Reviewed-by: Laura Abbott <labbott@redhat.com> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Mika Penttilä <mika.penttila@nextfour.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
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There is a race discovered by Juri, where we are able to: - create and read a sysfs file before policy->governor_data is being set to a non NULL value. OR - set policy->governor_data to NULL, and reading a file before being destroyed. And so such a crash is reported: Unable to handle kernel NULL pointer dereference at virtual address 0000000c pgd = edfc8000 [0000000c] *pgd=bfc8c835 Internal error: Oops: 17 [#1] SMP ARM Modules linked in: CPU: 4 PID: 1730 Comm: cat Not tainted 4.5.0-rc1+ #463 Hardware name: ARM-Versatile Express task: ee8e8480 ti: ee930000 task.ti: ee930000 PC is at show_ignore_nice_load_gov_pol+0x24/0x34 LR is at show+0x4c/0x60 pc : [<c058f1bc>] lr : [<c058ae88>] psr: a0070013 sp : ee931dd0 ip : ee931de0 fp : ee931ddc r10: ee4bc290 r9 : 00001000 r8 : ef2cb000 r7 : ee4bc200 r6 : ef2cb000 r5 : c0af57b0 r4 : ee4bc2e0 r3 : 00000000 r2 : 00000000 r1 : c0928df4 r0 : ef2cb000 Flags: NzCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 10c5387d Table: adfc806a DAC: 00000051 Process cat (pid: 1730, stack limit = 0xee930210) Stack: (0xee931dd0 to 0xee932000) 1dc0: ee931dfc ee931de0 c058ae88 c058f1a4 1de0: edce3bc0 c07bfca4 edce3ac0 00001000 ee931e24 ee931e00 c01fcb90 c058ae48 1e00: 00000001 edce3bc0 00000000 00000001 ee931e50 ee8ff480 ee931e34 ee931e28 1e20: c01fb33c c01fcb0c ee931e8c ee931e38 c01a5210 c01fb314 ee931e9c ee931e48 1e40: 00000000 edce3bf0 befe4a00 ee931f78 00000000 00000000 000001e4 00000000 1e60: c00545a8 edce3ac0 00001000 00001000 befe4a00 ee931f78 00000000 00001000 1e80: ee931ed4 ee931e90 c01fbed8 c01a5038 ed085a58 00020000 00000000 00000000 1ea0: c0ad72e4 ee931f78 ee8ff488 ee8ff480 c077f3fc 00001000 befe4a00 ee931f78 1ec0: 00000000 00001000 ee931f44 ee931ed8 c017c328 c01fbdc4 00001000 00000000 1ee0: ee8ff480 00001000 ee931f44 ee931ef8 c017c65c c03deb10 ee931fac ee931f08 1f00: c0009270 c001f290 c0a8d968 ef2cb000 ef2cb000 ee8ff480 00000020 ee8ff480 1f20: ee8ff480 befe4a00 00001000 ee931f78 00000000 00000000 ee931f74 ee931f48 1f40: c017d1ec c017c2f8 c019c724 c019c684 ee8ff480 ee8ff480 00001000 befe4a00 1f60: 00000000 00000000 ee931fa4 ee931f78 c017d2a8 c017d160 00000000 00000000 1f80: 000a9f20 00001000 befe4a00 00000003 c000ffe4 ee930000 00000000 ee931fa8 1fa0: c000fe40 c017d264 000a9f20 00001000 00000003 befe4a00 00001000 00000000 Unable to handle kernel NULL pointer dereference at virtual address 0000000c 1fc0: 000a9f20 00001000 befe4a00 00000003 00000000 00000000 00000003 00000001 pgd = edfc4000 [0000000c] *pgd=bfcac835 1fe0: 00000000 befe49dc 000197f8 b6e35dfc 60070010 00000003 3065b49d 134ac2c9 [<c058f1bc>] (show_ignore_nice_load_gov_pol) from [<c058ae88>] (show+0x4c/0x60) [<c058ae88>] (show) from [<c01fcb90>] (sysfs_kf_seq_show+0x90/0xfc) [<c01fcb90>] (sysfs_kf_seq_show) from [<c01fb33c>] (kernfs_seq_show+0x34/0x38) [<c01fb33c>] (kernfs_seq_show) from [<c01a5210>] (seq_read+0x1e4/0x4e4) [<c01a5210>] (seq_read) from [<c01fbed8>] (kernfs_fop_read+0x120/0x1a0) [<c01fbed8>] (kernfs_fop_read) from [<c017c328>] (__vfs_read+0x3c/0xe0) [<c017c328>] (__vfs_read) from [<c017d1ec>] (vfs_read+0x98/0x104) [<c017d1ec>] (vfs_read) from [<c017d2a8>] (SyS_read+0x50/0x90) [<c017d2a8>] (SyS_read) from [<c000fe40>] (ret_fast_syscall+0x0/0x1c) Code: e5903044 e1a00001 e3081df4 e34c1092 (e593300c) ---[ end trace 5994b9a5111f35ee ]--- Fix that by making sure, policy->governor_data is updated at the right places only. Cc: 4.2+ <stable@vger.kernel.org> # 4.2+ Reported-and-tested-by: Juri Lelli <juri.lelli@arm.com> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
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The size of all_zeros_mac is 6 byte, but eth_hash() will access the 8 byte, and KASan reported the below bug: [ 8596.479031] BUG: KASan: out of bounds access in __vxlan_find_mac+0x24/0x100 at addr ffffffff841514c0 [ 8596.487647] Read of size 8 by task ip/52820 [ 8596.490818] Address belongs to variable all_zeros_mac+0x0/0x40 [ 8596.496051] CPU: 0 PID: 52820 Comm: ip Tainted: G WC 4.1.15 #1 [ 8596.503520] Hardware name: HP ProLiant DL380p Gen8, BIOS P70 02/10/2014 [ 8596.509365] ffffffff841514c0 ffff88007450f0b8 ffffffff822fa5e1 0000000000000032 [ 8596.516112] ffff88007450f150 ffff88007450f138 ffffffff812dd58c ffff88007450f1d8 [ 8596.522856] ffffffff81113b80 0000000000000282 0000000000000001 ffffffff8101ee4d [ 8596.529599] Call Trace: [ 8596.530858] [<ffffffff822fa5e1>] dump_stack+0x4f/0x7b [ 8596.535080] [<ffffffff812dd58c>] kasan_report_error+0x3bc/0x3f0 [ 8596.540258] [<ffffffff81113b80>] ? __lock_acquire+0x90/0x2140 [ 8596.545245] [<ffffffff8101ee4d>] ? save_stack_trace+0x2d/0x80 [ 8596.550234] [<ffffffff812dda70>] kasan_report+0x40/0x50 [ 8596.554647] [<ffffffff81b211e4>] ? __vxlan_find_mac+0x24/0x100 [ 8596.559729] [<ffffffff812dc399>] __asan_load8+0x69/0xa0 [ 8596.564141] [<ffffffff81b211e4>] __vxlan_find_mac+0x24/0x100 [ 8596.569033] [<ffffffff81b2683d>] vxlan_fdb_create+0x9d/0x570 it can be fixed by enlarging the all_zeros_mac to 8 byte, although it is harmless; eth_hash() will be called in other place with the memory which is larger and equal to 8 byte. Signed-off-by: Li RongQing <roy.qing.li@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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