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author | Vincent Whitchurch <vincent.whitchurch@axis.com> | 2018-08-21 17:25:07 +0200 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-09-05 09:26:42 +0200 |
commit | 63a0f9de021aac2491be8466e44f35b07e3127b1 (patch) | |
tree | 0eb1d6ffa26951bceddcce9aea148017568ce772 | |
parent | f9f67667e0aeeafa65b4542c3d67173871baedfd (diff) | |
download | linux-rt-63a0f9de021aac2491be8466e44f35b07e3127b1.tar.gz |
watchdog: Mark watchdog touch functions as notrace
commit cb9d7fd51d9fbb329d182423bd7b92d0f8cb0e01 upstream.
Some architectures need to use stop_machine() to patch functions for
ftrace, and the assumption is that the stopped CPUs do not make function
calls to traceable functions when they are in the stopped state.
Commit ce4f06dcbb5d ("stop_machine: Touch_nmi_watchdog() after
MULTI_STOP_PREPARE") added calls to the watchdog touch functions from
the stopped CPUs and those functions lack notrace annotations. This
leads to crashes when enabling/disabling ftrace on ARM kernels built
with the Thumb-2 instruction set.
Fix it by adding the necessary notrace annotations.
Fixes: ce4f06dcbb5d ("stop_machine: Touch_nmi_watchdog() after MULTI_STOP_PREPARE")
Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: oleg@redhat.com
Cc: tj@kernel.org
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20180821152507.18313-1-vincent.whitchurch@axis.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r-- | kernel/watchdog.c | 4 | ||||
-rw-r--r-- | kernel/watchdog_hld.c | 2 | ||||
-rw-r--r-- | kernel/workqueue.c | 2 |
3 files changed, 4 insertions, 4 deletions
diff --git a/kernel/watchdog.c b/kernel/watchdog.c index c8e06703e44c..087994b23f8b 100644 --- a/kernel/watchdog.c +++ b/kernel/watchdog.c @@ -265,7 +265,7 @@ static void __touch_watchdog(void) * entering idle state. This should only be used for scheduler events. * Use touch_softlockup_watchdog() for everything else. */ -void touch_softlockup_watchdog_sched(void) +notrace void touch_softlockup_watchdog_sched(void) { /* * Preemption can be enabled. It doesn't matter which CPU's timestamp @@ -274,7 +274,7 @@ void touch_softlockup_watchdog_sched(void) raw_cpu_write(watchdog_touch_ts, 0); } -void touch_softlockup_watchdog(void) +notrace void touch_softlockup_watchdog(void) { touch_softlockup_watchdog_sched(); wq_watchdog_touch(raw_smp_processor_id()); diff --git a/kernel/watchdog_hld.c b/kernel/watchdog_hld.c index e449a23e9d59..4ece6028007a 100644 --- a/kernel/watchdog_hld.c +++ b/kernel/watchdog_hld.c @@ -29,7 +29,7 @@ static struct cpumask dead_events_mask; static unsigned long hardlockup_allcpu_dumped; static atomic_t watchdog_cpus = ATOMIC_INIT(0); -void arch_touch_nmi_watchdog(void) +notrace void arch_touch_nmi_watchdog(void) { /* * Using __raw here because some code paths have diff --git a/kernel/workqueue.c b/kernel/workqueue.c index d8a7f8939c81..08bc551976b2 100644 --- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -5484,7 +5484,7 @@ static void wq_watchdog_timer_fn(unsigned long data) mod_timer(&wq_watchdog_timer, jiffies + thresh); } -void wq_watchdog_touch(int cpu) +notrace void wq_watchdog_touch(int cpu) { if (cpu >= 0) per_cpu(wq_watchdog_touched_cpu, cpu) = jiffies; |