On Thu, Mar 30, 2023 at 1:15 AM Michal Hocko <mhocko@xxxxxxxx> wrote: > > On Thu 30-03-23 01:06:26, Yosry Ahmed wrote: > [...] > > If we achieve that, do you think it makes sense to add > > WARN_ON_ONCE(irqs_disabled()) instead to prevent future users from > > flushing while disabling irqs or in irq context? > > WARN_ON (similar to BUG_ON) will not prevent anybody from doing bad > things. We already have means to shout about sleepable code being > invoked from an atomic context and there is no reason to duplicate that. > As I've said earlier WARN_ON might panic the system in some > configurations (and yes they are used also in production systems - do > not ask me why...). So please be careful about that and use that only > when something really bad (yet recoverable) is going on. Thanks for the information (I was about to ask why about production systems, but okay..). I will avoid WARN_ON completely. For the purposes of this series I will drop this patch anyway. Any idea how to shout about "hey this may take too long, why are you doing it with irqs disabled?!"? > > -- > Michal Hocko > SUSE Labs