On Wed, 21 Aug 2019, Frederic Weisbecker wrote:
> On Mon, Aug 19, 2019 at 04:31:48PM +0200, Thomas Gleixner wrote:
> > run_posix_cpu_timers() is called from the timer interrupt. The posix timer
> > expiry always affects the current task which got interrupted.
> >
> > sighand locking is only racy when done on a foreign task, which must use
> > lock_task_sighand(). But in case of run_posix_cpu_timers() that's
> > pointless.
> >
> > sighand of a task can only be dropped or changed by the task itself. Drop
> > happens in do_exit()
>
> Well, that's only in case of autoreap. Otherwise this is dropped by the
> reaper.
Right, but in the reaper case the task cannot be on the CPU running and
being interrupted by the tick. I might be missing something subtle though.
Thanks,
tglx
