Merge pull request #81 from bobuhiro11/fix_rdinit

busybox: clean up files under /dev and startup script

Author: bobuhiro11

Makefile

@@ -38,6 +38,10 @@ initrd: busybox.config busybox.tar.bz2 busybox.inittab busybox.passwd busybox.rc
 	mkdir -p _busybox/_install/etc/init.d
 	mkdir -p _busybox/_install/proc
 	mkdir -p _busybox/_install/sys
+	mkdir -p _busybox/_install/dev
+	[ -e _busybox/_install/dev/null ] || mknod _busybox/_install/dev/null c   1 3
+	[ -e _busybox/_install/dev/zero ] || mknod _busybox/_install/dev/zero c   1 5
+	[ -e _busybox/_install/dev/vda  ] || mknod _busybox/_install/dev/vda  b 254 0
 	rm -f _busybox/_install/usr/bin/lspci
 	cp _pciutils/lspci _busybox/_install/usr/bin/lspci
 	cp _pciutils/pci.ids _busybox/_install/usr/local/share/pci.ids
@@ -47,7 +51,6 @@ initrd: busybox.config busybox.tar.bz2 busybox.inittab busybox.passwd busybox.rc
 	cp busybox.rcS     _busybox/_install/etc/init.d/rcS
 	sed -i -e 's|{{ GUEST_IPV4_ADDR }}|$(GUEST_IPV4_ADDR)|g' _busybox/_install/etc/init.d/rcS
 	cd _busybox/_install && find . | cpio -o --format=newc > ../../initrd
-	rm -rf _busybox
 
 linux.tar.xz:
 	curl --retry 5 https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-$(LINUX_VERSION).tar.xz \

busybox.rcS

@@ -1,19 +1,10 @@
 #!/bin/sh
 mount -t proc none /proc
 mount -t sysfs none /sys
-
-mknod /dev/vda b 254 0
+mount -t tmpfs tmpfs /run
+mount --bind /dev /dev
+mount --bind /dev/pts /dev/pts
+/sbin/mdev -s
 
 ip link set eth0 up
 ip addr add {{ GUEST_IPV4_ADDR }} dev eth0
-
-# DIRTY HACK:
-#
-# Forcing /linuxrc to stop processing here and start /bin/sh. Without it,
-# kernel will try to mount the disk provided by virtio-blk as rootfs and
-# finally panic.
-#
-# [  559.258478][    T1] Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(0,0)
-# [  559.258478][    T1] Kernel Offset: disabled
-# [  559.258478][    T1] ---[ end Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(0,0) ]---
-exec /bin/sh

flag/flag.go

@@ -14,7 +14,7 @@ func ParseArgs(args []string) (string, string, string, string, int, error) {
 	params := flag.String("p", `console=ttyS0 earlyprintk=serial noapic noacpi notsc `+
 		`debug apic=debug show_lapic=all mitigations=off lapic tsc_early_khz=2000 `+
 		`dyndbg="file arch/x86/kernel/smpboot.c +plf ; file drivers/net/virtio_net.c +plf" pci=realloc=off `+
-		`virtio_pci.force_legacy=1 rdinit=/linuxrc`, "kernel command-line parameters")
+		`virtio_pci.force_legacy=1 rdinit=/sbin/init`, "kernel command-line parameters")
 
 	flag.Parse()
 

linux.config

@@ -908,7 +908,9 @@ CONFIG_BLK_DEV=y
 # CONFIG_BLK_DEV_DRBD is not set
 # CONFIG_BLK_DEV_NBD is not set
 # CONFIG_BLK_DEV_SX8 is not set
-# CONFIG_BLK_DEV_RAM is not set
+CONFIG_BLK_DEV_RAM=y
+CONFIG_BLK_DEV_RAM_COUNT=16
+CONFIG_BLK_DEV_RAM_SIZE=4096
 # CONFIG_CDROM_PKTCDVD is not set
 # CONFIG_ATA_OVER_ETH is not set
 CONFIG_VIRTIO_BLK=y

machine/machine_test.go

@@ -20,7 +20,7 @@ func TestNewAndLoadLinux(t *testing.T) { // nolint:paralleltest
 	}
 
 	param := `console=ttyS0 earlyprintk=serial noapic noacpi notsc ` +
-		`lapic tsc_early_khz=2000 pci=realloc=off virtio_pci.force_legacy=1 rdinit=/linuxrc`
+		`lapic tsc_early_khz=2000 pci=realloc=off virtio_pci.force_legacy=1 rdinit=/sbin/init`
 
 	if err = m.LoadLinux("../bzImage", "../initrd", param); err != nil {
 		t.Fatal(err)