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charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Wed, Jan 03, 2024 at 05:14:19PM +0800, peterx@redhat.com wrote: > From: Peter Xu > > Introduce "pud_t pud" in the function, so the code won't dereference *pudp > multiple time. Not only because that looks less straightforward, but also > because if the dereference really happened, it's not clear whether there > can be race to see different *pudp values if it's being modified at the > same time. > > Acked-by: James Houghton > Signed-off-by: Peter Xu > --- > mm/gup.c | 17 +++++++++-------- > 1 file changed, 9 insertions(+), 8 deletions(-) I think we have several more case like this, and I ceratinly agree code should not access a READ_ONCE variable more than once :( Reviewed-by: Jason Gunthorpe Jason _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel