[ added Peter ] On Tue, 22 Apr 2014 13:54:39 +0200 Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx> wrote: > this is, erm, harmless. We grab the timer lock via trylock in hardirq > context. If the lock is already taken then we fail to get it we go for > plan B. According to lockdep a trylock should not fail on UP. This is > true in general except for this timer case. I was thinking abour > disabling this lockdep check… trylock not failing on UP, can that be an issue? I mean, if a hardirq does a trylock to see if it can grab a lock that is not protected by disabling irqs, and will go to plan B if it fails, on UP, it will always get it. But the issue is still there. That would mean that a hardirq could have preempted a critical section and doing a trylock here would succeed when it really should have failed. -- Steve -- To unsubscribe from this list: send the line "unsubscribe linux-rt-users" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html