Re: [Qemu-devel] Regression with commit 095497ffc66b7f031

[Paolo Bonzini]

On 15/07/2016 12:12, Gerd Hoffmann wrote:
> On Fr, 2016-07-15 at 12:02 +0200, Paolo Bonzini wrote:
>>
>> On 15/07/2016 10:47, Juergen Gross wrote:
>>> Nothing scaring and no real difference between working and not working
>>> variant.
>>>
>>> Meanwhile I've been digging a little bit deeper and found the reason:
>>> libxenstore is setting up a reader thread which is waiting for the
>>> watch to fire. With above commit the stack size of that thread (16kB)
>>> is too small. Setting it to 32kB made qemu work again.
>>
>> This makes very little sense (not your fault)...  The commit doesn't
>> change stack usage at all, TLS should not be on the stack.
>>
>> Can you capture a backtrace where the 16K stack is exceeded?  Perhaps
>> it's only due to inlining decision on the compiler, in which case
>> Peter's patch from today is only a bandaid.
> 
> Hmm, I guess I hold off the vnc pull request for now ...

Go ahead.  I looked at glibc source code and the patch is okay.

Paolo