Commit-ID: cb9d7fd51d9fbb329d182423bd7b92d0f8cb0e01
Gitweb: https://git.kernel.org/tip/cb9d7fd51d9fbb329d182423bd7b92d0f8cb0e01
Author: Vincent Whitchurch <vincent.whitchu...@axis.com>
AuthorDate: Tue, 21 Aug 2018 17:25:07 +0200
Committer: Thomas Gleixner <t...@linutronix.de>
CommitDate: Thu, 30 Aug 2018 12:56:40 +0200
watchdog: Mark watchdog touch functions as notrace
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.whitchu...@axis.com>
Signed-off-by: Thomas Gleixner <t...@linutronix.de>
Cc: Peter Zijlstra <pet...@infradead.org>
Cc: o...@redhat.com
Cc: t...@kernel.org
Cc: sta...@vger.kernel.org
Link:
https://lkml.kernel.org/r/20180821152507.18313-1-vincent.whitchu...@axis.com
---
kernel/watchdog.c | 4 ++--
kernel/watchdog_hld.c | 2 +-
kernel/workqueue.c | 2 +-
3 files changed, 4 insertions(+), 4 deletions(-)
diff --git a/kernel/watchdog.c b/kernel/watchdog.c
index 5470dce212c0..977918d5d350 100644
--- a/kernel/watchdog.c
+++ b/kernel/watchdog.c
@@ -261,7 +261,7 @@ 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
@@ -270,7 +270,7 @@ 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 1f7020d65d0a..71381168dede 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 60e80198c3df..0280deac392e 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -5574,7 +5574,7 @@ static void wq_watchdog_timer_fn(struct timer_list
*unused)
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;
