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> > enum rseq_cs_flags_bit { > diff --git a/kernel/rseq.c b/kernel/rseq.c > index c4bc52f8ba9c..997f7ca722ca 100644 > --- a/kernel/rseq.c > +++ b/kernel/rseq.c > @@ -576,6 +576,23 @@ SYSCALL_DEFINE4(rseq, struct rseq __user *, rseq, u32, rseq_len, > return 0; > } > > + /* > + * return supported rseq_cs flags > + * It is an or of all the rseq_cs_flags; > + */ > + if (flags & RSEQ_FLAG_QUERY_CS_FLAGS) { > + u32 rseq_csflags = RSEQ_CS_FLAG_NO_RESTART_ON_PREEMPT | > + RSEQ_CS_FLAG_NO_RESTART_ON_SIGNAL | > + RSEQ_CS_FLAG_NO_RESTART_ON_MIGRATE | Those 3 flags (above) are already or'd by RSEQ_CS_NO_RESTART_FLAGS, and they are all deprecated. See rseq_warn_flags(). So I would not return them within the set of supported rseq flags. Thanks, Mathieu > + RSEQ_CS_FLAG_DELAY_RESCHED | > + RSEQ_CS_FLAG_RESCHEDULED; > + if (!rseq) > + return -EINVAL; > + if (copy_to_user(&rseq->flags, &rseq_csflags, sizeof(u32))) > + return -EFAULT; > + return 0; > + } > + > if (unlikely(flags)) > return -EINVAL; > -- Mathieu Desnoyers EfficiOS Inc. https://www.efficios.com