repair kernel
flamer die.spam@hotmail.com
told me it was updating the modules in the kernel and when it
completed i should reboot the syste. i followed the instructions but
the upgrade damaged the system and made it unbootable.
I am able to get to a prompt through the install cd where I can see
my /boot directory etc, but how can I go about copying over the
existing kernel with the stable one from the cd? (or is there a better
way to do it?) I cant find where the cd files are etc and do i need to
install the file, or just copy it over?
any help is greatly appreciated.
Flamer
Mike Bleiweiss
After a kernel upgrade, Debian keeps the old kernel images just in case
there are problems with the new one. All you have to do is boot the
earlier kernel version in your grub menu. Once you've gotten into the
system, just edit your /boot/grub/menu.lst file to make the old kernel
image the default.
flamer die.spam@hotmail.com
Hi I tried that, it wasn't actually a new kernel, it was the same
kernel release but with updated modules (so it said) but yues there is
definitely only one copy of the kernel on there (which must be the
same version as the one on the install disc too) but I have a feeling
if I can overwrite it with the one from the disc it should work.
jellybean stonerfish
> Hi I have a debian etch system, i recently ran an apt-get upgrade, it
> told me it was updating the modules in the kernel and when it completed
> i should reboot the syste. i followed the instructions but the upgrade
> damaged the system and made it unbootable.
>
By "unbootable", what do mean?
Do you get any messages on the screen at all?
Are you sure the problem is with your kernel?
> I am able to get to a prompt through the install cd where I can see my
> /boot directory etc, but how can I go about copying over the existing
> kernel with the stable one from the cd? (or is there a better way to do
> it?) I cant find where the cd files are etc and do i need to install the
> file, or just copy it over?
>
> any help is greatly appreciated.
Don't write over the kernel on your hard disk unless you are sure that is
the problem.
>
> Flamer
stonerfish
Mike Bleiweiss
> Hi I tried that, it wasn't actually a new kernel, it was the same kernel
> release but with updated modules (so it said) but yues there is
> definitely only one copy of the kernel on there (which must be the same
> version as the one on the install disc too) but I have a feeling if I
> can overwrite it with the one from the disc it should work.
Yeah - if that's the only kernel you have, then you'll have to replace it
by booting from a livecd and moving it over. Also - if you know which
module is causing the problem, you can disable or remove the module from
a boot cd as well.
There's a nice writeup here:
http://www.cyberciti.biz/faq/add-remove-list-linux-kernel-modules/
flamer die.spam@hotmail.com
wrote:
it will boot past grub and at the point I get a console dump on my
screen.. not exactly sure what it all means but I can't get past it,
have tried single user mode and the same thing happens.
all I know is I did an apt-get upgrade, it said it was updating the
kernel, then it told me the kernel i was trying to update to was the
same version as the one I already had, then it said it was updating
the modules in the kernel and that is was critical I reboot the system
(after doing so the system could then not load debian).
So based on those events thats why i believe the problem to be in the
kernel.
Flamer.
flamer die.spam@hotmail.com
>
> There's a nice writeup here:http://www.cyberciti.biz/faq/add-remove-list-linux-kernel-modules/
thanks I have had a read of that, unfortunately I don't know which
module is causing the issues.
Do you know where I can find info on copying the kernel over? I dont
feel too comfortable int he rescue cli and don't want to do any more
damage. Also another question, any applications that I have added or
upgraded since the install (such as php, postfix etc) will they be
over written or will they stay put?
Flamer.
jellybean stonerfish
> On Aug 20, 2:15 am, jellybean stonerfish <stonerf...@geocities.com>
> wrote:
>> On Sat, 16 Aug 2008 21:45:34 -0700, flamer die.s...@hotmail.com wrote:
>> > Hi I have a debian etch system, i recently ran an apt-get upgrade, it
>> > told me it was updating the modules in the kernel and when it
>> > completed i should reboot the syste. i followed the instructions but
>> > the upgrade damaged the system and made it unbootable.
>>
>> By "unbootable", what do mean?
>> Do you get any messages on the screen at all?
>> Are you sure the problem is with your kernel?
>>
<<SNIP>>
>>
>> stonerfish
>
> it will boot past grub and at the point I get a console dump on my
> screen.. not exactly sure what it all means but I can't get past it,
> have tried single user mode and the same thing happens.
>
<<SNIP>>
>
> Flamer.
If you tell us what text is dumped to the screen, or at least the last
feww lines of it, we would be better able to help you.
Also, could you tell us what your kernel line is on your grub menu.
( Hit 'e' on the grub screen to see that. )
stonerfish
flamer die.spam@hotmail.com
wrote:
Hi here is the info I have been able to find:
kernel: 2.6.18-4-amd64
kernel line:
root (hd0,0)
kernel /boot/vmlinuz-2.6.18-4-amd64 root=/dev/sda1 ro
initrd /boot/initrd.img-2.6.18-4-amd64
savedefault
the crash code is:
7e f9 e9 d4 fe ff ff f3 90 83 3f 00 7e f9 e9 d3 fe ff ff f3
anymore info on this would be greatly appreciated as I havent been
able to get any further..
jellybean stonerfish
> On Aug 20, 1:39 pm, jellybean stonerfish <stonerf...@geocities.com>
>>
>> If you tell us what text is dumped to the screen, or at least the last
>> feww lines of it, we would be better able to help you.
>>
>> Also, could you tell us what your kernel line is on your grub menu. (
>> Hit 'e' on the grub screen to see that. )
>>
>> stonerfish
>
> Hi here is the info I have been able to find:
>
> kernel: 2.6.18-4-amd64
>
> kernel line:
> root (hd0,0)
> kernel /boot/vmlinuz-2.6.18-4-amd64 root=/dev/sda1 ro initrd
> /boot/initrd.img-2.6.18-4-amd64 savedefault
>
> the crash code is:
> 7e f9 e9 d4 fe ff ff f3 90 83 3f 00 7e f9 e9 d3 fe ff ff f3
>
After grub starts to load the kernel, if this is all you get, I haven't a
clue. There was no other text on the screen?
> anymore info on this would be greatly appreciated as I havent been able
> to get any further..
Maybe someone with skill will rise up and tell us what that code above
means.
stonerfish
flamer die.spam@hotmail.com
wrote:
Stonerfish, I get pages and pages of console dump when it crashes, I
don't have an easy way to copy it other than write it out manually, if
there is anything in particular I should be looking for that may make
it easier for me?
Flamer
jellybean stonerfish
OK. the code you already posted is the last line, yes?
How about the lines before it. Maybe that will tell us when it stops.
Then we can figure out what is broken.
flamer die.spam@hotmail.com
wrote:
Hi Stonerfish, yes the line above is the very last line. Below is some
more of the dump, there was a few lines of hex above this and that was
all I can see on screen.
-snip-
process udevd(pid:449)
-snip-
call trace
_downgrade_write+0x21/0x66
hrtimer_get_remaining+0x1f0x3f
__up_read+0x13/x8a
itimer_get_remtime+0xd/0x35
do_setitimer+0xa4/0x4bf
do_sigaction+0x7a/0x19e
alarm_setitimer+0x35/0x65
sys_alarm+0x9/0xe
system_call+0x7e/0x83
Hope this provides more useful info, thanks for your help so far.
Flamer.