This is a note to let you know that I've just added the patch titled
powerpc/pseries: Mark accumulate_stolen_time() as notrace
to the 4.14-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:
powerpc-pseries-mark-accumulate_stolen_time-as-notra.patch
and it can be found in the queue-4.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit af9761aefceaa444aa60ae776d0e440be01be60f
Author: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Date: Sun Oct 13 21:23:51 2019 +1100
powerpc/pseries: Mark accumulate_stolen_time() as notrace
[ Upstream commit eb8e20f89093b64f48975c74ccb114e6775cee22 ]
accumulate_stolen_time() is called prior to interrupt state being
reconciled, which can trip the warning in arch_local_irq_restore():
WARNING: CPU: 5 PID: 1017 at arch/powerpc/kernel/irq.c:258 .arch_local_irq_restore+0x9c/0x130
...
NIP .arch_local_irq_restore+0x9c/0x130
LR .rb_start_commit+0x38/0x80
Call Trace:
.ring_buffer_lock_reserve+0xe4/0x620
.trace_function+0x44/0x210
.function_trace_call+0x148/0x170
.ftrace_ops_no_ops+0x180/0x1d0
ftrace_call+0x4/0x8
.accumulate_stolen_time+0x1c/0xb0
decrementer_common+0x124/0x160
For now just mark it as notrace. We may change the ordering to call it
after interrupt state has been reconciled, but that is a larger
change.
Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20191024055932.27940-1-mpe@xxxxxxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/arch/powerpc/kernel/time.c b/arch/powerpc/kernel/time.c
index 14f3f28a089e..66a9987dc0f8 100644
--- a/arch/powerpc/kernel/time.c
+++ b/arch/powerpc/kernel/time.c
@@ -241,7 +241,7 @@ static u64 scan_dispatch_log(u64 stop_tb)
* Accumulate stolen time by scanning the dispatch trace log.
* Called on entry from user mode.
*/
-void accumulate_stolen_time(void)
+void notrace accumulate_stolen_time(void)
{
u64 sst, ust;
u8 save_soft_enabled = local_paca->soft_enabled;
