This is a note to let you know that I've just added the patch titled
s390: don't trace preemption in percpu macros
to the 4.9-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-don-t-trace-preemption-in-percpu-macros.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 70b439905f1525479f7b9802c61dd3749e1b6766
Author: Sven Schnelle <svens@xxxxxxxxxxxxx>
Date: Thu Aug 20 09:48:23 2020 +0200
s390: don't trace preemption in percpu macros
[ Upstream commit 1196f12a2c960951d02262af25af0bb1775ebcc2 ]
Since commit a21ee6055c30 ("lockdep: Change hardirq{s_enabled,_context}
to per-cpu variables") the lockdep code itself uses percpu variables. This
leads to recursions because the percpu macros are calling preempt_enable()
which might call trace_preempt_on().
Signed-off-by: Sven Schnelle <svens@xxxxxxxxxxxxx>
Reviewed-by: Vasily Gorbik <gor@xxxxxxxxxxxxx>
Signed-off-by: Vasily Gorbik <gor@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/arch/s390/include/asm/percpu.h b/arch/s390/include/asm/percpu.h
index 90240dfef76a1..5889c1ed84c46 100644
--- a/arch/s390/include/asm/percpu.h
+++ b/arch/s390/include/asm/percpu.h
@@ -28,7 +28,7 @@
typedef typeof(pcp) pcp_op_T__; \
pcp_op_T__ old__, new__, prev__; \
pcp_op_T__ *ptr__; \
- preempt_disable(); \
+ preempt_disable_notrace(); \
ptr__ = raw_cpu_ptr(&(pcp)); \
prev__ = *ptr__; \
do { \
@@ -36,7 +36,7 @@
new__ = old__ op (val); \
prev__ = cmpxchg(ptr__, old__, new__); \
} while (prev__ != old__); \
- preempt_enable(); \
+ preempt_enable_notrace(); \
new__; \
})
@@ -67,7 +67,7 @@
typedef typeof(pcp) pcp_op_T__; \
pcp_op_T__ val__ = (val); \
pcp_op_T__ old__, *ptr__; \
- preempt_disable(); \
+ preempt_disable_notrace(); \
ptr__ = raw_cpu_ptr(&(pcp)); \
if (__builtin_constant_p(val__) && \
((szcast)val__ > -129) && ((szcast)val__ < 128)) { \
@@ -83,7 +83,7 @@
: [val__] "d" (val__) \
: "cc"); \
} \
- preempt_enable(); \
+ preempt_enable_notrace(); \
}
#define this_cpu_add_4(pcp, val) arch_this_cpu_add(pcp, val, "laa", "asi", int)
@@ -94,14 +94,14 @@
typedef typeof(pcp) pcp_op_T__; \
pcp_op_T__ val__ = (val); \
pcp_op_T__ old__, *ptr__; \
- preempt_disable(); \
+ preempt_disable_notrace(); \
ptr__ = raw_cpu_ptr(&(pcp)); \
asm volatile( \
op " %[old__],%[val__],%[ptr__]\n" \
: [old__] "=d" (old__), [ptr__] "+Q" (*ptr__) \
: [val__] "d" (val__) \
: "cc"); \
- preempt_enable(); \
+ preempt_enable_notrace(); \
old__ + val__; \
})
@@ -113,14 +113,14 @@
typedef typeof(pcp) pcp_op_T__; \
pcp_op_T__ val__ = (val); \
pcp_op_T__ old__, *ptr__; \
- preempt_disable(); \
+ preempt_disable_notrace(); \
ptr__ = raw_cpu_ptr(&(pcp)); \
asm volatile( \
op " %[old__],%[val__],%[ptr__]\n" \
: [old__] "=d" (old__), [ptr__] "+Q" (*ptr__) \
: [val__] "d" (val__) \
: "cc"); \
- preempt_enable(); \
+ preempt_enable_notrace(); \
}
#define this_cpu_and_4(pcp, val) arch_this_cpu_to_op(pcp, val, "lan")
@@ -135,10 +135,10 @@
typedef typeof(pcp) pcp_op_T__; \
pcp_op_T__ ret__; \
pcp_op_T__ *ptr__; \
- preempt_disable(); \
+ preempt_disable_notrace(); \
ptr__ = raw_cpu_ptr(&(pcp)); \
ret__ = cmpxchg(ptr__, oval, nval); \
- preempt_enable(); \
+ preempt_enable_notrace(); \
ret__; \
})
@@ -151,10 +151,10 @@
({ \
typeof(pcp) *ptr__; \
typeof(pcp) ret__; \
- preempt_disable(); \
+ preempt_disable_notrace(); \
ptr__ = raw_cpu_ptr(&(pcp)); \
ret__ = xchg(ptr__, nval); \
- preempt_enable(); \
+ preempt_enable_notrace(); \
ret__; \
})
@@ -170,11 +170,11 @@
typeof(pcp1) *p1__; \
typeof(pcp2) *p2__; \
int ret__; \
- preempt_disable(); \
+ preempt_disable_notrace(); \
p1__ = raw_cpu_ptr(&(pcp1)); \
p2__ = raw_cpu_ptr(&(pcp2)); \
ret__ = __cmpxchg_double(p1__, p2__, o1__, o2__, n1__, n2__); \
- preempt_enable(); \
+ preempt_enable_notrace(); \
ret__; \
})
