kernel 4.4 and 4.9 different reactions to initrd.

kernel 4.4 and 4.9 different reactions to initrd.

[Ali H.M. Hoseini]

Hi,

I'm not sure am I supposed to ask this question here, But I did not
find anywhere more suitable!

I'm using a complete root fs compressed in gz as my initrd for last
couple of years.
until kernel 4.4.x when I chose to boot kernel with my initrd, I got
these messages in boot process:

...
[    0.000000] Krrne  oomman  iie: BOOT_IMAGE=vvmlinuz-4.4117
initrd=/utvos44.0.6.gz console=tty console=ttyS09900
...
[   38.920053] Trying to unpack rootfs image as initramfs...
[   39.103577] rootfs image is not initramfs (no cpio magic); looks
like an initrd
[   39.488596] Freeing initrd memory: 46576K (ffff88007d284000 -
ffff880080000000)
....
[   60.815224] RAMDISK: gzip image found at block 0
[   64.617699] EXT4-fs (ram0): couldn't mount as ext3 due to feature
incompatibilities
[   64.835669] EXT4-fs (ram0): couldn't mount as ext2 due to feature
incompatibilities
[   65.168935] EXT4-fs (ram0): mounted filesystem with ordered data
mode. Opts: (null)
[   65.498876] VFS: Mounted root (ext4 filesystem) on device 1:0.
mounting fstab entries
...

and system boots correctly.



But when I switched to kernel 4.9.30, everything went wrong:

....
[    0.000000] Kernel command line: BOOT_IMAGE=/vmlinuz-4.9.30
initrd=/utvos.4.1.0.gz root=/dev/ram0 console=tty console=ttyS0,9600
....
[   29.156899] Unpacking initramfs...
[   29.330796] Initramfs unpacking failed: no cpio magic
...
[   50.444213] VFS: Cannot open root device "ram0" or
unknown-block(0,0): error -6
[   50.656876] Please append a correct "root=" boot option; here are
the available partitions:
[   51.012293] Kernel panic - not syncing: VFS: Unable to mount root
fs on unknown-block(0,0)
....

I've tried adding root=/dev/ram0, removing it, adding keepinitrd
kernel switch, changing archive compression to cpio, and multiple
other kernel paramters, but nothing helped.

Basically it seems old kernel detects image is initrd
(rootfs image is not initramfs (no cpio magic); looks like an initrd),
but new kernel doesn't even try to mount image as initrd.

What is wrong? how should I fix this problem.

Best regards.

Re: kernel 4.4 and 4.9 different reactions to initrd.

[Andrei Borzenkov]

22.06.2017 23:30, Ali H.M. Hoseini пишет:
> Hi,
> 
> I'm not sure am I supposed to ask this question here, But I did not
> find anywhere more suitable!
> 
> I'm using a complete root fs compressed in gz as my initrd for last
> couple of years.
> until kernel 4.4.x when I chose to boot kernel with my initrd, I got
> these messages in boot process:
> 
> ...
> [    0.000000] Krrne  oomman  iie: BOOT_IMAGE=vvmlinuz-4.4117
> initrd=/utvos44.0.6.gz console=tty console=ttyS09900
> ...
> [   38.920053] Trying to unpack rootfs image as initramfs...
> [   39.103577] rootfs image is not initramfs (no cpio magic); looks
> like an initrd
> ...
> 
> and system boots correctly.
> 
> 
> 
> But when I switched to kernel 4.9.30, everything went wrong:
> 
> ....
> [    0.000000] Kernel command line: BOOT_IMAGE=/vmlinuz-4.9.30
> initrd=/utvos.4.1.0.gz root=/dev/ram0 console=tty console=ttyS0,9600
> ....
> [   29.156899] Unpacking initramfs...
> [   29.330796] Initramfs unpacking failed: no cpio magic
> ...

You need CONFIG_BLK_DEV_RAM enabled. Looks like it is not define in this
case.

Re: kernel 4.4 and 4.9 different reactions to initrd.

[Ali H.M. Hoseini]

Hi,

Thank you very much. it seems during boot with default ubuntu kernels,
CONFIG_BLK_DEV_RAM changed to =m.
Correcting it to =y and recompiling kernel fixed the problem.

Thanks again.



On Fri, Jun 23, 2017 at 8:06 AM, Andrei Borzenkov <arvidjaar-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:
> 22.06.2017 23:30, Ali H.M. Hoseini пишет:
>> Hi,
>>
>> I'm not sure am I supposed to ask this question here, But I did not
>> find anywhere more suitable!
>>
>> I'm using a complete root fs compressed in gz as my initrd for last
>> couple of years.
>> until kernel 4.4.x when I chose to boot kernel with my initrd, I got
>> these messages in boot process:
>>
>> ...
>> [    0.000000] Krrne  oomman  iie: BOOT_IMAGE=vvmlinuz-4.4117
>> initrd=/utvos44.0.6.gz console=tty console=ttyS09900
>> ...
>> [   38.920053] Trying to unpack rootfs image as initramfs...
>> [   39.103577] rootfs image is not initramfs (no cpio magic); looks
>> like an initrd
>> ...
>>
>> and system boots correctly.
>>
>>
>>
>> But when I switched to kernel 4.9.30, everything went wrong:
>>
>> ....
>> [    0.000000] Kernel command line: BOOT_IMAGE=/vmlinuz-4.9.30
>> initrd=/utvos.4.1.0.gz root=/dev/ram0 console=tty console=ttyS0,9600
>> ....
>> [   29.156899] Unpacking initramfs...
>> [   29.330796] Initramfs unpacking failed: no cpio magic
>> ...
>
> You need CONFIG_BLK_DEV_RAM enabled. Looks like it is not define in this
> case.