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 4.4-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-4.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 337db7b4c19e29d379d0ae789f49224f6079d494 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 2e9cae5f8d17..397076474a71 100644 --- a/arch/powerpc/kernel/time.c +++ b/arch/powerpc/kernel/time.c @@ -245,7 +245,7 @@ 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;