The patch titled Subject: memtest: use {READ,WRITE}_ONCE in memory scanning has been added to the -mm mm-unstable branch. Its filename is memtest-use-readwrite_once-in-memory-scanning.patch

This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches...

This patch will later appear in the mm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------ From: Qiang Zhang qiang4.zhang@intel.com Subject: memtest: use {READ,WRITE}_ONCE in memory scanning Date: Tue, 12 Mar 2024 16:04:23 +0800

memtest failed to find bad memory when compiled with clang. So use {WRITE,READ}_ONCE to access memory to avoid compiler over optimization.

Link: https://lkml.kernel.org/r/20240312080422.691222-1-qiang4.zhang@intel.com Signed-off-by: Qiang Zhang qiang4.zhang@intel.com Cc: Bill Wendling morbo@google.com Cc: Justin Stitt justinstitt@google.com Cc: Nathan Chancellor nathan@kernel.org Cc: Nick Desaulniers ndesaulniers@google.com Cc: stable@vger.kernel.org Signed-off-by: Andrew Morton akpm@linux-foundation.org ---

mm/memtest.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/mm/memtest.c~memtest-use-readwrite_once-in-memory-scanning +++ a/mm/memtest.c @@ -51,10 +51,10 @@ static void __init memtest(u64 pattern, last_bad = 0;

for (p = start; p < end; p++) - *p = pattern; + WRITE_ONCE(*p, pattern);

for (p = start; p < end; p++, start_phys_aligned += incr) { - if (*p == pattern) + if (READ_ONCE(*p) == pattern) continue; if (start_phys_aligned == last_bad + incr) { last_bad += incr; _

Patches currently in -mm which might be from qiang4.zhang@intel.com are

memtest-use-readwrite_once-in-memory-scanning.patch