This is a note to let you know that I've just added the patch titled
s390: Initialize psw mask in perf_arch_fetch_caller_regs()
to the 6.6-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
s390-initialize-psw-mask-in-perf_arch_fetch_caller_r.patch
and it can be found in the queue-6.6 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 9d41d3560575dc9fce646fb9c176716088ddcf81
Author: Heiko Carstens <hca@xxxxxxxxxxxxx>
Date: Thu Oct 10 17:52:39 2024 +0200
s390: Initialize psw mask in perf_arch_fetch_caller_regs()
[ Upstream commit 223e7fb979fa06934f1595b6ad0ae1d4ead1147f ]
Also initialize regs->psw.mask in perf_arch_fetch_caller_regs().
This way user_mode(regs) will return false, like it should.
It looks like all current users initialize regs to zero, so that this
doesn't fix a bug currently. However it is better to not rely on callers
to do this.
Fixes: 914d52e46490 ("s390: implement perf_arch_fetch_caller_regs")
Signed-off-by: Heiko Carstens <hca@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/arch/s390/include/asm/perf_event.h b/arch/s390/include/asm/perf_event.h
index 9917e2717b2b4..66aff768f8151 100644
--- a/arch/s390/include/asm/perf_event.h
+++ b/arch/s390/include/asm/perf_event.h
@@ -73,6 +73,7 @@ struct perf_sf_sde_regs {
#define SAMPLE_FREQ_MODE(hwc) (SAMPL_FLAGS(hwc) & PERF_CPUM_SF_FREQ_MODE)
#define perf_arch_fetch_caller_regs(regs, __ip) do { \
+ (regs)->psw.mask = 0; \
(regs)->psw.addr = (__ip); \
(regs)->gprs[15] = (unsigned long)__builtin_frame_address(0) - \
offsetof(struct stack_frame, back_chain); \
