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| author | Heiko Carstens <hca@linux.ibm.com> | 2023-01-09 13:51:20 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-01-18 13:44:54 +0300 |
| commit | 51dbedee2ff3b000c9905189e33e1972b6c9f649 (patch) | |
| tree | 22d435a666edb7f85d9b594ff7fb04bdc803c78c | |
| parent | bddb355267849423306cc9dc313783303dd19f03 (diff) | |
| download | linux-51dbedee2ff3b000c9905189e33e1972b6c9f649.tar.xz | |
s390/percpu: add READ_ONCE() to arch_this_cpu_to_op_simple()
commit e3f360db08d55a14112bd27454e616a24296a8b0 upstream.
Make sure that *ptr__ within arch_this_cpu_to_op_simple() is only
dereferenced once by using READ_ONCE(). Otherwise the compiler could
generate incorrect code.
Cc: <stable@vger.kernel.org>
Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | arch/s390/include/asm/percpu.h | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/s390/include/asm/percpu.h b/arch/s390/include/asm/percpu.h index 918f0ba4f4d2..5e26e2c4641b 100644 --- a/arch/s390/include/asm/percpu.h +++ b/arch/s390/include/asm/percpu.h @@ -31,7 +31,7 @@ pcp_op_T__ *ptr__; \ preempt_disable_notrace(); \ ptr__ = raw_cpu_ptr(&(pcp)); \ - prev__ = *ptr__; \ + prev__ = READ_ONCE(*ptr__); \ do { \ old__ = prev__; \ new__ = old__ op (val); \ |