Bug#656608: grub2 on sqeeze and bugs triggered by qemu/kvm

[Michael Tokarev]

Package: grub2
Version: 1.98+20100804-14+squeeze1
Severity: wishlist
Tags: squeeze

Hello.

I've two bugreports reported against qemu-kvm package about
squeeze virtual machines being unbootable.  These are
#653068 and #616487.  It all boils down to the following
message during boot (from #653068):

 Loading Linux 2.6.32-5-amd64 ...
 unaligned pointer 0x93940002
 Aborted. Press any key to exit.

After some investigation it turns out this is a problem
in grub itself, its memory management.  In particular,
I found this:

 https://bugs.launchpad.net/ubuntu/+source/grub2/+bug/717445

In this bugreport, they found out that later grub versions
does not show this issue.  This is confirmed by my bureports --
installing grub from wheezy makes it work.

In the LP#717445 there's a backport of a large commit to
grub made by Serge Hallyn.  He backported a commit which
made lots of changes to video subsystem handling, see

 https://bugs.launchpad.net/ubuntu/+source/grub2/+bug/717445/comments/11

I tried the 3 patches against grub in squeeze, had to
tweak some stuff in there, and can confirm it fixes the
mentioned problem, which confirms what ubuntu guys
discovered.

Now, the question.  It is definitely worth to fix this
bug for squeeze, so it will be actually installable in
qemu/kvm.  It is obviously not possible to fix it for
past squeeze releases, so original squeeze will remain
uninstallable which is sad.  It is not really possible
to fix it in qemu/kvm because tje behavor - as far as
I can see - depends on quite some randomness.  And
finally, the backport of that large patch is, well,
large and may be too risky for squeeze if it is about
to fix just qemu/kvm problem.

Any opinions/comments?

For now I'll merge the two mentioned bugreports into
this one, and mark it with Severity: wishlist.

Thanks,

/mjt