Re: 2.6.38-rc3 regression on parisc: segfaults

From: Carlos O'Donell
Date: Fri Feb 04 2011 - 10:20:21 EST


On Fri, Feb 4, 2011 at 10:07 AM, John David Anglin
<dave@xxxxxxxxxxxxxxxxxx> wrote:
> On Fri, 04 Feb 2011, Meelis Roos wrote:
>
>> 2363  clone( <unfinished ...>
>> 2349  <... futex resumed> )             = 1
>> 2363  <... clone resumed> child_stack=0, flags=CLONE_CHILD_CLEARTID|CLONE_CHILD_SETTID|SIGCHLD, child_tidptr=0x460df4a8) = 2372
>> 2349  --- SIGSEGV (Segmentation fault) @ 0 (0) ---
>> 2372  rt_sigaction(SIGPIPE, {SIG_DFL, [], SA_RESTART},  <unfinished ...>
>> 2349  write(1, "\33[56;1H\33[34h\33[?25h", 18 <unfinished ...>
>>
>> Something futex-related. Full log temprarilty available at
>> http://www.cs.ut.ee/~mroos/aptitude-strace.txt
>
> This is possibly the infamous COW bug.

The COW bug that is triggered by a COW from an LWS-CAS? The solution
to which is to use locks around the LWS-CAS even on UP? I'd forgotten
about this issue actually, I should push that patch out to James.

Cheers,
Carlos.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/