WIP: try out custom config annotation

Documentation/admin-guide/kernel-parameters.txt

@@ -225,14 +225,23 @@
 			For broken nForce2 BIOS resulting in XT-PIC timer.
 
 	acpi_sleep=	[HW,ACPI] Sleep options
-			Format: { s3_bios, s3_mode, s3_beep, s4_nohwsig,
-				  old_ordering, nonvs, sci_force_enable, nobl }
+			Format: { s3_bios, s3_mode, s3_beep, s4_hwsig,
+				  s4_nohwsig, old_ordering, nonvs,
+				  sci_force_enable, nobl }
 			See Documentation/power/video.rst for information on
 			s3_bios and s3_mode.
 			s3_beep is for debugging; it makes the PC's speaker beep
 			as soon as the kernel's real-mode entry point is called.
+			s4_hwsig causes the kernel to check the ACPI hardware
+			signature during resume from hibernation, and gracefully
+			refuse to resume if it has changed. This complies with
+			the ACPI specification but not with reality, since
+			Windows does not do this and many laptops do change it
+			on docking. So the default behaviour is to allow resume
+			and simply warn when the signature changes, unless the
+			s4_hwsig option is enabled.
 			s4_nohwsig prevents ACPI hardware signature from being
-			used during resume from hibernation.
+			used (or even warned about) during resume.
 			old_ordering causes the ACPI 1.0 ordering of the _PTS
 			control method, with respect to putting devices into
 			low power states, to be enforced (the ACPI 2.0 ordering

Documentation/virt/ne_overview.rst

@@ -14,12 +14,15 @@ instances [1].
 For example, an application that processes sensitive data and runs in a VM,
 can be separated from other applications running in the same VM. This
 application then runs in a separate VM than the primary VM, namely an enclave.
+It runs alongside the VM that spawned it. This setup matches low latency
+applications needs.
 
-An enclave runs alongside the VM that spawned it. This setup matches low latency
-applications needs. The resources that are allocated for the enclave, such as
-memory and CPUs, are carved out of the primary VM. Each enclave is mapped to a
-process running in the primary VM, that communicates with the NE driver via an
-ioctl interface.
+The current supported architectures for the NE kernel driver, available in the
+upstream Linux kernel, are x86 and ARM64.
+
+The resources that are allocated for the enclave, such as memory and CPUs, are
+carved out of the primary VM. Each enclave is mapped to a process running in the
+primary VM, that communicates with the NE kernel driver via an ioctl interface.
 
 In this sense, there are two components:
 
@@ -43,8 +46,8 @@ for the enclave VM. An enclave does not have persistent storage attached.
 The memory regions carved out of the primary VM and given to an enclave need to
 be aligned 2 MiB / 1 GiB physically contiguous memory regions (or multiple of
 this size e.g. 8 MiB). The memory can be allocated e.g. by using hugetlbfs from
-user space [2][3]. The memory size for an enclave needs to be at least 64 MiB.
-The enclave memory and CPUs need to be from the same NUMA node.
+user space [2][3][7]. The memory size for an enclave needs to be at least
+64 MiB. The enclave memory and CPUs need to be from the same NUMA node.
 
 An enclave runs on dedicated cores. CPU 0 and its CPU siblings need to remain
 available for the primary VM. A CPU pool has to be set for NE purposes by an
@@ -61,7 +64,7 @@ device is placed in memory below the typical 4 GiB.
 The application that runs in the enclave needs to be packaged in an enclave
 image together with the OS ( e.g. kernel, ramdisk, init ) that will run in the
 enclave VM. The enclave VM has its own kernel and follows the standard Linux
-boot protocol [6].
+boot protocol [6][8].
 
 The kernel bzImage, the kernel command line, the ramdisk(s) are part of the
 Enclave Image Format (EIF); plus an EIF header including metadata such as magic
@@ -93,3 +96,5 @@ enclave process can exit.
 [4] https://www.kernel.org/doc/html/latest/admin-guide/kernel-parameters.html
 [5] https://man7.org/linux/man-pages/man7/vsock.7.html
 [6] https://www.kernel.org/doc/html/latest/x86/boot.html
+[7] https://www.kernel.org/doc/html/latest/arm64/hugetlbpage.html
+[8] https://www.kernel.org/doc/html/latest/arm64/booting.html

Makefile

@@ -518,9 +518,6 @@ LINUXINCLUDE    := \
 		-I$(objtree)/include \
 		$(USERINCLUDE)
 
-# UBUNTU: Include our third party driver stuff too
-LINUXINCLUDE   += -I$(srctree)/ubuntu/include
-
 KBUILD_AFLAGS   := -D__ASSEMBLY__ -fno-PIE
 KBUILD_CFLAGS   := -Wall -Wundef -Werror=strict-prototypes -Wno-trigraphs \
 		   -fno-strict-aliasing -fno-common -fshort-wchar -fno-PIE \
@@ -675,7 +672,7 @@ endif
 ifeq ($(KBUILD_EXTMOD),)
 # Objects we will link into vmlinux / subdirs we need to visit
 core-y		:= init/ usr/ arch/$(SRCARCH)/
-drivers-y	:= drivers/ sound/ ubuntu/
+drivers-y	:= drivers/ sound/
 drivers-$(CONFIG_SAMPLES) += samples/
 drivers-$(CONFIG_NET) += net/
 drivers-y	+= virt/
@@ -1351,7 +1348,6 @@ headers: $(version_h) scripts_unifdef uapi-asm-generic archheaders archscripts
 	$(if $(filter um, $(SRCARCH)), $(error Headers not exportable for UML))
 	$(Q)$(MAKE) $(hdr-inst)=include/uapi
 	$(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi
-	$(Q)$(MAKE) $(hdr-inst)=ubuntu/include dst=include oldheaders=
 
 # Deprecated. It is no-op now.
 PHONY += headers_check

Ubuntu.md

@@ -1,8 +1,8 @@
-Name:    linux
+Name:    linux-aws-5.15
 Version: 5.15.0
-Series:  22.04 (jammy)
+Series:  20.04 (focal)
 Description:
-    This is the source code for the Ubuntu linux kernel for the 22.04 series. This
-    source tree is used to produce the flavours: generic, generic-64k, generic-lpae, lowlatency.
+    This is the source code for the Ubuntu linux kernel for the 20.04 series. This
+    source tree is used to produce the flavours: aws.
     This kernel is configured to support the widest range of desktop, laptop and
     server configurations.

arch/x86/kernel/acpi/sleep.c

@@ -15,6 +15,7 @@
 #include <asm/desc.h>
 #include <asm/cacheflush.h>
 #include <asm/realmode.h>
+#include <asm/hypervisor.h>
 
 #include <linux/ftrace.h>
 #include "../../realmode/rm/wakeup.h"
@@ -139,8 +140,10 @@ static int __init acpi_sleep_setup(char *str)
 		if (strncmp(str, "s3_beep", 7) == 0)
 			acpi_realmode_flags |= 4;
 #ifdef CONFIG_HIBERNATION
+		if (strncmp(str, "s4_hwsig", 8) == 0)
+			acpi_check_s4_hw_signature = 1;
 		if (strncmp(str, "s4_nohwsig", 10) == 0)
-			acpi_no_s4_hw_signature();
+			acpi_check_s4_hw_signature = 0;
 #endif
 		if (strncmp(str, "nonvs", 5) == 0)
 			acpi_nvs_nosave();
@@ -158,3 +161,21 @@ static int __init acpi_sleep_setup(char *str)
 }
 
 __setup("acpi_sleep=", acpi_sleep_setup);
+
+#if defined(CONFIG_HIBERNATION) && defined(CONFIG_HYPERVISOR_GUEST)
+static int __init init_s4_sigcheck(void)
+{
+	/*
+	 * If running on a hypervisor, honour the ACPI specification
+	 * by default and trigger a clean reboot when the hardware
+	 * signature in FACS is changed after hibernation.
+	 */
+	if (acpi_check_s4_hw_signature == -1 &&
+	    !hypervisor_is_type(X86_HYPER_NATIVE))
+		acpi_check_s4_hw_signature = 1;
+
+	return 0;
+}
+/* This must happen before acpi_init() which is a subsys initcall */
+arch_initcall(init_s4_sigcheck);
+#endif

arch/x86/kernel/tsc.c

@@ -15,6 +15,7 @@
 #include <linux/timex.h>
 #include <linux/static_key.h>
 #include <linux/static_call.h>
+#include <linux/suspend.h>
 
 #include <asm/hpet.h>
 #include <asm/timer.h>
@@ -1575,3 +1576,31 @@ unsigned long calibrate_delay_is_known(void)
 	return 0;
 }
 #endif
+
+static int tsc_pm_notifier(struct notifier_block *notifier,
+                          unsigned long pm_event, void *unused)
+{
+	switch (pm_event) {
+	case PM_HIBERNATION_PREPARE:
+		clear_sched_clock_stable();
+		break;
+	case PM_POST_HIBERNATION:
+		/* Set back to the default */
+		if (!check_tsc_unstable())
+			set_sched_clock_stable();
+		break;
+	}
+
+	return 0;
+};
+
+static struct notifier_block tsc_pm_notifier_block = {
+       .notifier_call = tsc_pm_notifier,
+};
+
+static int tsc_setup_pm_notifier(void)
+{
+       return register_pm_notifier(&tsc_pm_notifier_block);
+}
+
+subsys_initcall(tsc_setup_pm_notifier);

arch/x86/xen/enlighten_hvm.c

@@ -29,6 +29,13 @@
 
 static unsigned long shared_info_pfn;
 
+void xen_hvm_map_shared_info(void)
+{
+        xen_hvm_init_shared_info();
+        if(shared_info_pfn)
+                 HYPERVISOR_shared_info = __va(PFN_PHYS(shared_info_pfn));
+}
+
 void xen_hvm_init_shared_info(void)
 {
 	struct xen_add_to_physmap xatp;
@@ -212,6 +219,7 @@ static void __init xen_hvm_guest_init(void)
 	if (!no_vector_callback && xen_feature(XENFEAT_hvm_callback_vector))
 		xen_have_vector_callback = 1;
 
+	xen_setup_syscore_ops();
 	xen_hvm_smp_init();
 	WARN_ON(xen_cpuhp_setup(xen_cpu_up_prepare_hvm, xen_cpu_dead_hvm));
 	xen_unplug_emulated_devices();

arch/x86/xen/suspend.c

@@ -2,17 +2,22 @@
 #include <linux/types.h>
 #include <linux/tick.h>
 #include <linux/percpu-defs.h>
+#include <linux/syscore_ops.h>
+#include <linux/kernel_stat.h>
 
 #include <xen/xen.h>
 #include <xen/interface/xen.h>
+#include <xen/interface/memory.h>
 #include <xen/grant_table.h>
 #include <xen/events.h>
+#include <xen/xen-ops.h>
 
 #include <asm/cpufeatures.h>
 #include <asm/msr-index.h>
 #include <asm/xen/hypercall.h>
 #include <asm/xen/page.h>
 #include <asm/fixmap.h>
+#include <asm/pvclock.h>
 
 #include "xen-ops.h"
 #include "mmu.h"
@@ -82,3 +87,65 @@ void xen_arch_suspend(void)
 
 	on_each_cpu(xen_vcpu_notify_suspend, NULL, 1);
 }
+
+static int xen_syscore_suspend(void)
+{
+	struct xen_remove_from_physmap xrfp;
+	int cpu, ret;
+
+	/* Xen suspend does similar stuffs in its own logic */
+	if (xen_suspend_mode_is_xen_suspend())
+		return 0;
+
+	for_each_present_cpu(cpu) {
+		/*
+		 * Nonboot CPUs are already offline, but the last copy of
+		 * runstate info is still accessible.
+		 */
+		xen_save_steal_clock(cpu);
+	}
+
+	xen_shutdown_pirqs();
+
+	xrfp.domid = DOMID_SELF;
+	xrfp.gpfn = __pa(HYPERVISOR_shared_info) >> PAGE_SHIFT;
+
+	ret = HYPERVISOR_memory_op(XENMEM_remove_from_physmap, &xrfp);
+	if (!ret)
+		HYPERVISOR_shared_info = &xen_dummy_shared_info;
+
+	return ret;
+}
+
+static void xen_syscore_resume(void)
+{
+	/* Xen suspend does similar stuffs in its own logic */
+	if (xen_suspend_mode_is_xen_suspend())
+		return;
+
+	/* No need to setup vcpu_info as it's already moved off */
+	xen_hvm_map_shared_info();
+
+	pvclock_resume();
+
+	/* Nonboot CPUs will be resumed when they're brought up */
+	xen_restore_steal_clock(smp_processor_id());
+
+	gnttab_resume();
+
+}
+
+/*
+ * These callbacks will be called with interrupts disabled and when having only
+ * one CPU online.
+ */
+static struct syscore_ops xen_hvm_syscore_ops = {
+	.suspend = xen_syscore_suspend,
+	.resume = xen_syscore_resume
+};
+
+void __init xen_setup_syscore_ops(void)
+{
+	if (xen_hvm_domain())
+		register_syscore_ops(&xen_hvm_syscore_ops);
+}

arch/x86/xen/time.c

@@ -548,6 +548,9 @@ static void xen_hvm_setup_cpu_clockevents(void)
 {
 	int cpu = smp_processor_id();
 	xen_setup_runstate_info(cpu);
+	if (cpu)
+		xen_restore_steal_clock(cpu);
+
 	/*
 	 * xen_setup_timer(cpu) - snprintf is bad in atomic context. Hence
 	 * doing it xen_hvm_cpu_notify (which gets called by smp_init during

arch/x86/xen/xen-ops.h

@@ -56,6 +56,8 @@ void xen_enable_sysenter(void);
 void xen_enable_syscall(void);
 void xen_vcpu_restore(void);
 
+void xen_callback_vector(void);
+void xen_hvm_map_shared_info(void);
 void xen_hvm_init_shared_info(void);
 void xen_unplug_emulated_devices(void);
 

debian.aws-5.15/abi/abiname

@@ -0,0 +1 @@
+1040