aio: add missing smp_rmb() in read_events_ring

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We ran into a case on ppc64 running mariadb where io_getevents would
return zeroed out I/O events.  After adding instrumentation, it became
clear that there was some missing synchronization between reading the
tail pointer and the events themselves.  This small patch fixes the
problem in testing.

Thanks to Zach for helping to look into this, and suggesting the fix.

Signed-off-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Benjamin LaHaise <bcrl@kvack.org>
Cc: stable@vger.kernel.org

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Jeff Moyer 2014-09-02 13:17:00 -04:00 • committed by Benjamin LaHaise

parent 7be141d055

commit 2ff396be60

1 changed files with 6 additions and 0 deletions

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fs/aio.c

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