I am trying to build a minimalistic kernel and initrd image which I want to use with qemu.
I am packing initrd image using cpio by,
find . | cpio -oHnewc | gzip > ../initrd.img
The kernel loads and mounts RAM disk image fine provided I don't keep anything in /lib/modules. The moment I keep the kernel modules in there the RAM disk image doesn't get mounted and fails with following error,
I1114 14:44:07.171914 30333 proxy.go:135] vmconsole: [ 0.231680] RAMDISK: Couldn't find valid RAM disk image starting at 0.
I1114 14:44:07.172070 30333 proxy.go:135] vmconsole: [ 0.231853] List of all partitions:
I1114 14:44:07.172100 30333 proxy.go:135] vmconsole: [ 0.231877] 0100 65536 ram0 (driver?)
I1114 14:44:07.172131 30333 proxy.go:135] vmconsole: [ 0.231907] 0101 65536 ram1 (driver?)
I1114 14:44:07.172162 30333 proxy.go:135] vmconsole: [ 0.231937] 0102 65536 ram2 (driver?)
I1114 14:44:07.172188 30333 proxy.go:135] vmconsole: [ 0.231967] 0103 65536 ram3 (driver?)
I1114 14:44:07.172218 30333 proxy.go:135] vmconsole: [ 0.231995] 0104 65536 ram4 (driver?)
I1114 14:44:07.172252 30333 proxy.go:135] vmconsole: [ 0.232026] 0105 65536 ram5 (driver?)
I1114 14:44:07.172278 30333 proxy.go:135] vmconsole: [ 0.232057] 0106 65536 ram6 (driver?)
I1114 14:44:07.172309 30333 proxy.go:135] vmconsole: [ 0.232085] 0107 65536 ram7 (driver?)
I1114 14:44:07.172337 30333 proxy.go:135] vmconsole: [ 0.232114] 0108 65536 ram8 (driver?)
I1114 14:44:07.172367 30333 proxy.go:135] vmconsole: [ 0.232143] 0109 65536 ram9 (driver?)
I1114 14:44:07.172398 30333 proxy.go:135] vmconsole: [ 0.232173] 010a 65536 ram10 (driver?)
I1114 14:44:07.172423 30333 proxy.go:135] vmconsole: [ 0.232201] 010b 65536 ram11 (driver?)
I1114 14:44:07.172452 30333 proxy.go:135] vmconsole: [ 0.232230] 010c 65536 ram12 (driver?)
I1114 14:44:07.172482 30333 proxy.go:135] vmconsole: [ 0.232259] 010d 65536 ram13 (driver?)
I1114 14:44:07.172513 30333 proxy.go:135] vmconsole: [ 0.232288] 010e 65536 ram14 (driver?)
I1114 14:44:07.172542 30333 proxy.go:135] vmconsole: [ 0.232319] 010f 65536 ram15 (driver?)
I1114 14:44:07.172622 30333 proxy.go:135] vmconsole: [ 0.232348] No filesystem could mount root, tried: ext3 ext2 ext4 squashfs vfat fuseblk
I1114 14:44:07.172665 30333 proxy.go:135] vmconsole: [ 0.232429] Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(1,0)
I1114 14:44:07.172701 30333 proxy.go:135] vmconsole: [ 0.232472] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.4.87 #8
I1114 14:44:07.172714 30333 proxy.go:135] vmconsole: [ 0.232506] Call Trace:
I1114 14:44:07.172762 30333 proxy.go:135] vmconsole: [ 0.232523] [c00000000e3e3ae0] [c000000000b8a89c] dump_stack+0xb0/0xf0 (unreliable)
I1114 14:44:07.172807 30333 proxy.go:135] vmconsole: [ 0.232571] [c00000000e3e3b20] [c000000000b8841c] panic+0x100/0x2c0
I1114 14:44:07.172856 30333 proxy.go:135] vmconsole: [ 0.232614] [c00000000e3e3bb0] [c000000000f54890] mount_block_root+0x338/0x33c
I1114 14:44:07.172907 30333 proxy.go:135] vmconsole: [ 0.232664] [c00000000e3e3c70] [c000000000f54c94] prepare_namespace+0x1f4/0x254
I1114 14:44:07.172956 30333 proxy.go:135] vmconsole: [ 0.232714] [c00000000e3e3cf0] [c000000000f542b8] kernel_init_freeable+0x334/0x37c
I1114 14:44:07.173002 30333 proxy.go:135] vmconsole: [ 0.232765] [c00000000e3e3dc0] [c00000000000be0c] kernel_init+0x2c/0x160
I1114 14:44:07.173049 30333 proxy.go:135] vmconsole: [ 0.232808] [c00000000e3e3e30] [c000000000009538] ret_from_kernel_thread+0x5c/0xa4
I1114 14:44:07.174582 30333 proxy.go:135] vmconsole: [ 0.234339] ---[ end Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(1,0)
I am able to understand how by just adding the modules in initrd leads to this behaviour?
