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

[Gordan Bobic]

On 11/29/2011 02:42 PM, Andrew Haley wrote:
> On 11/29/2011 02:01 PM, Gordan Bobic wrote:
>> One other thing - one of the manifestations of this bug appears to be
>> random memory corruption (strange, I know - unless I am dealing with two
>> totally unrelated problems). Specifically, I have seen the bug manifest
>> during compile jobs where, for example, linking would segfault, and
>> re-making would segfault again. But doing:
>> echo 3>  /proc/sys/vm/drop_caches
>> would fix the problem.
>>
>> My first suspicion was duff hardware/RAM on my AC100. So I got another
>> one, and it behaves in the exact same way.
>
> The most likely explanation is that you've got a data race somewhere.
> SMP ARM, unlike x86, has a  weakly-ordered memory model.  Unless
> everyone is extremely careful, problems like the one you're describing
> are very likely.

Indeed, I was thinking about some kind of a concurrency issue, too, but 
the question is how to fix it. Assuming for a moment that it is not a 
kernel issue (other people are running he same kernel with Ubuntu 
without this problem), are we talking about glibc? Or are you saying 
that _any_ package could be responsible for such a thing?

How can this be fixed?

Gordan