From: Qiang Zhang <qiang4.zhang@intel.com>
To: Andrew Morton <akpm@linux-foundation.org>,
Nathan Chancellor <nathan@kernel.org>,
Nick Desaulniers <ndesaulniers@google.com>,
Bill Wendling <morbo@google.com>,
Justin Stitt <justinstitt@google.com>
Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org,
llvm@lists.linux.dev, Qiang Zhang <qiang4.zhang@intel.com>,
Stable@vger.kernel.org
Subject: [PATCH] memtest: use {READ,WRITE}_ONCE in memory scanning
Date: Tue, 12 Mar 2024 16:04:23 +0800 [thread overview]
Message-ID: <20240312080422.691222-1-qiang4.zhang@intel.com> (raw)
memtest failed to find bad memory when compiled with clang. So use
{WRITE,READ}_ONCE to access memory to avoid compiler over optimization.
Cc: <Stable@vger.kernel.org>
Signed-off-by: Qiang Zhang <qiang4.zhang@intel.com>
---
mm/memtest.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/mm/memtest.c b/mm/memtest.c
index 32f3e9dda837..c2c609c39119 100644
--- a/mm/memtest.c
+++ b/mm/memtest.c
@@ -51,10 +51,10 @@ static void __init memtest(u64 pattern, phys_addr_t start_phys, phys_addr_t size
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;
--
2.39.2
next reply other threads:[~2024-03-12 8:05 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-03-12 8:04 Qiang Zhang [this message]
2024-03-13 17:21 ` Nathan Chancellor
2024-03-15 6:24 ` Zhang, Qiang4
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