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Reviewed-by: Mathieu Desnoyers Thanks! Mathieu > > Fixes: 2a36ab717e8f ("rseq/membarrier: Add MEMBARRIER_CMD_PRIVATE_EXPEDITED_RSEQ") > Signed-off-by: Thomas Gleixner > Cc: Mathieu Desnoyers > Cc: Peter Zijlstra > Cc: "Paul E. McKenney" > Cc: Boqun Feng > Cc: stable@vger.kernel.org > --- > include/linux/rseq.h | 11 ++++++++--- > kernel/rseq.c | 10 +++++----- > 2 files changed, 13 insertions(+), 8 deletions(-) > > --- a/include/linux/rseq.h > +++ b/include/linux/rseq.h > @@ -7,6 +7,12 @@ > #include > #include > > +#ifdef CONFIG_MEMBARRIER > +# define RSEQ_EVENT_GUARD irq > +#else > +# define RSEQ_EVENT_GUARD preempt > +#endif > + > /* > * Map the event mask on the user-space ABI enum rseq_cs_flags > * for direct mask checks. > @@ -41,9 +47,8 @@ static inline void rseq_handle_notify_re > static inline void rseq_signal_deliver(struct ksignal *ksig, > struct pt_regs *regs) > { > - preempt_disable(); > - __set_bit(RSEQ_EVENT_SIGNAL_BIT, ¤t->rseq_event_mask); > - preempt_enable(); > + scoped_guard(RSEQ_EVENT_GUARD) > + __set_bit(RSEQ_EVENT_SIGNAL_BIT, ¤t->rseq_event_mask); > rseq_handle_notify_resume(ksig, regs); > } > > --- a/kernel/rseq.c > +++ b/kernel/rseq.c > @@ -342,12 +342,12 @@ static int rseq_need_restart(struct task > > /* > * Load and clear event mask atomically with respect to > - * scheduler preemption. > + * scheduler preemption and membarrier IPIs. > */ > - preempt_disable(); > - event_mask = t->rseq_event_mask; > - t->rseq_event_mask = 0; > - preempt_enable(); > + scoped_guard(RSEQ_EVENT_GUARD) { > + event_mask = t->rseq_event_mask; > + t->rseq_event_mask = 0; > + } > > return !!event_mask; > } -- Mathieu Desnoyers EfficiOS Inc. https://www.efficios.com