On Thu 11-03-21 09:46:30, Peter Zijlstra wrote: > On Wed, Mar 10, 2021 at 06:13:21PM -0800, Mike Kravetz wrote: > > from irq context. Changing the check in the code from !in_task to > > in_atomic would handle the situations when called with irqs disabled. > > It does not. local_irq_disable() does not change preempt_count(). You are right. Earlier I was suggesting to check of irq_disabled() as well http://lkml.kernel.org/r/YD4I+VPr3UNt063H@xxxxxxxxxxxxxx back then it was not really clear to me that in fact we do care about spin locks more than irq disabled code. I am not even sure whether we need to care about irq disabled regions without any locks held that wouldn't be covered by in_atomic. But it would be safer to add irq_disabled check as well. -- Michal Hocko SUSE Labs
