Messages in this thread | | | From | Andy Lutomirski <> | Date | Tue, 8 Dec 2020 20:12:06 -0800 | Subject | Re: [PATCH v3 2/4] membarrier: Add an actual barrier before rseq_preempt() |
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On Thu, Dec 3, 2020 at 9:07 PM Andy Lutomirski <luto@kernel.org> wrote: > > It seems to me that most RSEQ membarrier users will expect any > stores done before the membarrier() syscall to be visible to the > target task(s). While this is extremely likely to be true in > practice, nothing actually guarantees it by a strict reading of the > x86 manuals. Rather than providing this guarantee by accident and > potentially causing a problem down the road, just add an explicit > barrier. > > Cc: stable@vger.kernel.org
Fixes: 2a36ab717e8f ("rseq/membarrier: Add MEMBARRIER_CMD_PRIVATE_EXPEDITED_RSEQ")
which is new in 5.10, so it doesn't need cc:stable if it makes 5.10.
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