Kernel panic when using initramfs instead of initrd

[Max Filippov]

Hi Ivan,

On Sun, May 5, 2013 at 1:44 PM, Ivan Nikolaev <voidexp at gmail.com> wrote:
...
> EVERYTHING WORKS if I enable in the kernel some filesystem (like ext2 or
> squashfs) and create the initrd image of that type and put inside the
> contents of the directory. Isolinux then boots the kernel this way:
>
> LABEL linux
>     SAY Booting linux...
>     KERNEL /vmlinuz
>     APPEND root=/dev/ram0 initrd=/initrd.gz console=ttyS0,38400 vga=0x305
>
> To make this work, I obviously enabled the "Initial RAM filesystem and RAM
> disk (initramfs/initrd) support" in "General setup" and the "RAM block
> device support" in "Device drivers - block devices" options.
>
> Well, ensuring everything works, I tried to switch to initramfs. Disabled
> the "RAM block device support", the ext2 and squashfs filesystems and
> created the init cpio image with a command like this:
>
> find | cpio -H newc -o | gzip -9 > initrd.gz
>
> The boot arguments are the same. When I boot, what I have is a kernel panic
> with the following details:
>
> List of all partitions:
> No filesystem could mount root, tried:
> Kernel panic - not syncing: VFS: Unable to mount root fs on
> unknown-block(0,0)
>
> Here's my config file: http://pastebin.com/XVd8ZukU

Empty CONFIG_INITRAMFS_SOURCE parameter in your config
should actually look like

CONFIG_INITRAMFS_SOURCE="/path/to/your/initrd.gz"

given the command you use for initramfs creation, because initramfs
image is linked into the vmlinuz at the build time.

-- 
Thanks.
-- Max