[fedora-arm] Possible glibc bug manifesting only on SMP ARMv7 systems

[Gordan Bobic]

On 11/29/2011 01:45 PM, Peter Robinson wrote:
> On Tue, Nov 29, 2011 at 1:30 PM, Gordan Bobic<gordan at bobich.net>  wrote:
>> Guys,
>>
>> After chasing my tail for ages thinking I had a hardware issue on an
>> AC100, it looks like the random segfaults and "glibc detected a
>> corrupted doubly linked list" errors might actually be SMP and/or ARMv7
>> related.
>>
>> Errors:
>> - random segfaults
>> - glibc detected a corrupted doubly linked list
>>
>> Distro: Fedora 13
>>
>> Platforms that work flawlessly (24/7 compiling for weeks):
>> - Marvell Kirkwood (1x SheevaPlug, 1x DreamPlug).
>>
>> Platforms that cause repeatable segfaults (same rootfs, same operation):
>> - Tegra2 (tested using Toshiba AC100 and Compulab TrimSlice)
>> - OMAP 4xxx (tested on a PandaBoard)
>>
>> I'm going to dig into this deeper (boot the machine with nosmp or
>> tasksetting everything to run on the same core), but in the meantime I
>> would like to ask if there is a bug in any of the following:
>>
>> - glibc
>> - gcc
>> - binutils
>>
>> that might cause them to misbehave either on:
>> - ARMv7 (armv5tel packages on armv7l kernel)
>> or
>> - SMP ARM systems
>> (or both)
>>
>> I'm going to compile up a clean kernel (without all the hacks I tried on
>> the AC100 to try to troubleshoot the issue) and try building the
>> packages in a clean F13 mock just to do a definitive confirmation pass,
>> but if anyone is aware of any such issues (e.g. due to locking
>> primitives being different on ARMv7) that have been fixed in
>> glibc/gcc/binutils recently, I would appreciate any info you may have on
>> the subject.
>>
>> Ubuntu doesn't appear to suffer from this issue, but they use a much
>> newer gcc and a different glibc than what is in F13.
>
> Have you tried a F-14 rootfs?

Not yet, no. I'll try that when I have a clean recipe for demonstrating 
the problem on F13. In the meantime any pointers at bugs/patches for 
anything like this would be welcome.

Gordan