Re: boot failure, "DWARF2 unwinder stuck at 0xc0100199"

[Andrew Morton <akpm@osdl.org>]

On Sat, 19 Aug 2006 21:31:21 -0400
"J. Bruce Fields" <bfields@fieldses.org> wrote:

> As of 2.6.18-rc3, one of my test machines stopped booting.  I'm not
> seeing the whole OOPS (I could probably set up a serial console if
> necessary), but it ends in something like:
> 
> trace_hardirqs_on
> idesci_pc_intr
> ide_intr
> handle_IRQ_event
> __do_IRQ
> do_IRQ
> common_interrupt
> default_idle
> apm_cpu_idle
> cpu_idle
> rest_init
> start_kernel
> 0xc0100199
> DWARF2 unwinder stuck at 0xc0100199
> Leftover inexact backtrace:
>  =======================
>  BUG: unable to handle kernel paging request at virtual address 0000b034
>  printing eip:
> c0103712
> *pde = 00000000
> Recursive die() failure, output suppressed
>  <0>Kernel panic - not syncing: Fatal exception in interrupt
> 
> Bisecting, it looks like this starts happening after c97d20a...,
> "[PATCH] i386: Do backtrace fallback too", though it's a little tricky
> since the compile is broken near there for a little while.
> 
> Kernel config appended; let me know if anything else would be useful.

I think there were some unwinder fixes post-2.6.18-rc3.

We need to work out what's causing this oops asap, please.  Testing
2.6.8-r4-git1 (which should be available within the day) would be useful,
please.  If it crashes, it'll be serial console time.