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The compiler may > load it again later instead of keeping the zone it already read, so a > caller can check one zone and then use another, or the NULL terminator. > > Use READ_ONCE(). Callers that take a zone from a slot and keep using > it, such as get_page_from_freelist() with ac->preferred_zoneref, need > that single load. > > Fixes: 11cd8638c37f ("mm, page_alloc: remove stop_machine from build_all_= zonelists") > Cc: stable@vger.kernel.org > Signed-off-by: Gregory Price (Meta) > --- > include/linux/mmzone.h | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > LGTM. Acked-by: Zi Yan --=20 Best Regards, Yan, Zi