Re: [PATCH RT 00/39] Linux 3.14.34-rt32-rc1

From: Sebastian Andrzej Siewior
Date: Mon Mar 16 2015 - 10:10:29 EST


On 03/16/2015 03:02 PM, Steven Rostedt wrote:
> On Mon, 16 Mar 2015 14:59:10 +0100
> Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx> wrote:
>
>> * Steven Rostedt | 2015-03-12 15:13:07 [-0400]:
>>
>>> Please scream at me if I messed something up. Please test the patches too.
>>
>> So Paul remided us about the dead lock thingy that has been reported.
>> Users reported that it does not occur with v3.18-RT and they think it is
>> due to 'Revert "timers: do not raise softirq unconditionally"' in
>> Revert-timers-do-not-raise-softirq-unconditionally.patch.
>>
>> I reverted it because I couldn't get highres to get to work at all on
>> v3.18 due to different synchronisation / expectaion of the timer
>> framework. Since the trylock might record a different lock owner it is
>> possible that this causes the deadlock (it thinks). Therefore it has no
>> stable tag nor any reference to the deadlock problem.
>
> I guess the question is, is there any other place that does a trylock
> in hard irq context? If so, the revert isn't going to fix it.

This is the only place and I introduced it only for that reason.

>
> -- Steve

Sebastian

--
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/