Re: [gentoo-user] kernel panic on manually built kernel

[Coert Waagmeester]

dhk wrote:

On 11/08/2010 05:28 AM, Coert Waagmeester wrote:

Volker Armin Hemmann wrote:

On Thursday 04 November 2010, dhk wrote:

I've always used the genkernel, but now am trying to make a manual one.
 I think the kernel is alright since all the default setting seemed
reasonable and the build was easy enough.  However, when I boot to it I
get a kernel panic and it complains about the root device /dev/hda3. So
I think the problem has to do with my parameters or syntax in grub.conf.
 Below are three grub menu options.  The first two have the problem and
the third is the genkernel that works fine.  Is there something wrong
with the way the first two are?  Thanks.

# This is a Manually built kernel with default settings.  kernel panic
title Gentoo Linux x86 2.6.34-r12
root (hd0,0)
kernel /boot/kernel-2.6.34-gentoo-r12 root=/dev/hda3

# This is a Manually built kernel with default settings.  kernel panic
title Gentoo Linux x86 2.6.34-r12
root (hd0,0)
kernel /boot/kernel-2.6.34-gentoo-r12 root=/dev/hda3 vga=791
splash=verbose video=vesafb:mtrr,ywrap udev
# From Documentation: video=uvesafb:mtrr:3,ywrap,1024x768...@85

# This a genkernel and works
title Gentoo Linux x86 2.6.34-r6
root (hd0,0)
kernel /boot/kernel-genkernel-x86_64-2.6.34-gentoo-r6 init=/linuxrc
ramdisk=8192 real_root=/dev/hda3 vga=791 splash=verbose
video=vesafb:mtrr,ywrap udev
initrd /boot/initramfs-genkernel-x86_64-2.6.34-gentoo-r6

--dhk

grub must point to sda3 not hda3

Yes, I had a similar problem.
The device names are different on my machine between genkernel and my
own kernel.
Make sure to change that in your /etc/fstab as well.

Dont know if this is always the case though.

Regards,
Coert Waagmeester

I'm booting to an IDE hard disk.  Are you say the device name should
change from /dev/hda3 to /dev/sda3?  If I change it in /etc/fstab and it
doesn't work, I'll have problems, I'll probably have to boot to the livecd.

Thanks,

--dhk

It has indeed happened to me with an IDE PATA disk.
Try first only to change only your grub config.
Then if you see that the kernel boots fine, you can change /etc/fstab.

If you want you can even use LABELs in fstab.

give your ext{2,3} partitions labels with e2label

and change the device node eg /dev/hda1 in fstab to LABEL=yournewlabel


Regards,
Coert Waagmeester