Messages in this thread |  | | | Date | Fri, 21 Aug 2009 16:17:21 +0200 | | From | Ingo Molnar <> | | Subject | Re: [PATCH -tip/core/rcu 1/6] Cleanups and fixes for RCU in face of heavy CPU-hotplug stress |
| |
* Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> wrote:
> I would not trust this architecture for synchronization tests. > There has been reports of a hardware bug affecting the cmpxchg > instruction in the field. The load fence normally implied by the > semantic seems to be missing. AFAIK, AMD never acknowledged the > problem.
If cmpxchg was broken i'd be having far worse problems and very widely so.
FYI, this was the same box i prototyped/developed -rt on, which uses cmpxchg for _everything_.
That's not a proof of course (it's near impossible to prove the lack of a bug), but it's sure a strong indicator and you'll need to provide far more proof of misbehavior before i discount a bona fide regression on this box.
Ingo
|  |