On 23/06/22 12:46, Sebastian Andrzej Siewior wrote: > On 2022-06-15 16:53:55 [+0200], Juri Lelli wrote: > > Hi, > Hi, > > > My understanding is that we have > > > > fs/aio.c::read_events > > wait_event_interruptible_hrtimeout > > __wait_event_hrtimeout > > hrtimer_init_sleeper_on_stack <- this might mode |=HRTIMER_MODE_HARD on RT > > will set HRTIMER_MODE_HARD of might set HRTIMER_MODE_HARD if the task has elevated priority > (RT/DL). > > > hrtimer_start_range_ns > > WARN_ON_ONCE(!(mode & HRTIMER_MODE_HARD) ^ !timer->is_hard) > > fires since the latter doesn't see the change of mode done by > > init_sleeper > > correct. > > > The attached patch seems to cure the problem, although I'm not entirely > > sure it's the cleanest fix (if I'm right at all about it :). > > The problem seems to be that __wait_event_hrtimeout() does > hrtimer_start_range_ns() instead of hrtimer_sleeper_start_expires(). So > if you switch that, then it should go away. Ah, indeed. That looks simpler. :) Will test and put a v2 together. Thanks! Juri
