On Thu, 2 May 2013 11:36:56 +0200 Daniel Vetter <daniel.vet...@ffwll.ch> wrote:
> On Thu, May 2, 2013 at 10:58 AM, Imre Deak <imre.d...@intel.com> wrote: > > Many callers of the wait_event_timeout() and > > wait_event_interruptible_timeout() expect that the return value will be > > positive if the specified condition becomes true before the timeout > > elapses. However, at the moment this isn't guaranteed. If the wake-up > > handler is delayed enough, the time remaining until timeout will be > > calculated as 0 - and passed back as a return value - even if the > > condition became true before the timeout has passed. > > > > Fix this by returning at least 1 if the condition becomes true. This > > semantic is in line with what wait_for_condition_timeout() does; see > > commit bb10ed09 - "sched: fix wait_for_completion_timeout() spurious > > failure under heavy load". > > > > Signed-off-by: Imre Deak <imre.d...@intel.com> > > We have 3 instances of this bug in drm/i915. One case even where we > switch between the interruptible and not interruptible > wait_event_timeout variants, foolishly presuming they have the same > semantics. I very much like this. Let's think about scheduling this fix. Are any of the bugs which we expect this patch fixes serious enough to warrant merging it into 3.10? And -stable? -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
