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The RCU read section needs to be > considered because all locks, which become sleeping locks on > PREEMPT_RT, start a RCU read section. Scheduling/ sleeping while within > a RCU read section is invalid. > > Check for also for RCU read section in stop_timeout() to determine if it > is safe to sleep. > > Signed-off-by: Sebastian Andrzej Siewior > Link: https://lore.kernel.org/r/20250714153954.629393-9-bigeasy@linutronix.de > Signed-off-by: Maarten Lankhorst Reviewed-by: Rodrigo Vivi > --- > drivers/gpu/drm/i915/gt/intel_engine_cs.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/i915/gt/intel_engine_cs.c b/drivers/gpu/drm/i915/gt/intel_engine_cs.c > index b721bbd233567..f5a6143ea8a24 100644 > --- a/drivers/gpu/drm/i915/gt/intel_engine_cs.c > +++ b/drivers/gpu/drm/i915/gt/intel_engine_cs.c > @@ -1609,7 +1609,7 @@ u64 intel_engine_get_last_batch_head(const struct intel_engine_cs *engine) > > static unsigned long stop_timeout(const struct intel_engine_cs *engine) > { > - if (in_atomic() || irqs_disabled()) /* inside atomic preempt-reset? */ > + if (in_atomic() || irqs_disabled() || rcu_preempt_depth()) /* inside atomic preempt-reset? */ > return 0; > > /* > -- > 2.45.2 >