4.9-stable review patch. If anyone has any objections, please let me know.
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From: Viresh Kumar viresh.kumar@linaro.org
commit 1fad17fb1bbcd73159c2b992668a6957ecc5af8a upstream.
If wakeup_source_add() is called right after wakeup_source_remove() for the same wakeup source, timer_setup() may be called for a potentially scheduled timer which is incorrect.
To avoid that, move the wakeup source timer cancellation from wakeup_source_drop() to wakeup_source_remove().
Moreover, make wakeup_source_remove() clear the timer function after canceling the timer to let wakeup_source_not_registered() treat unregistered wakeup sources in the same way as the ones that have never been registered.
Signed-off-by: Viresh Kumar viresh.kumar@linaro.org Cc: 4.4+ stable@vger.kernel.org # 4.4+ [ rjw: Subject, changelog, merged two patches together ] Signed-off-by: Rafael J. Wysocki rafael.j.wysocki@intel.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/base/power/wakeup.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-)
--- a/drivers/base/power/wakeup.c +++ b/drivers/base/power/wakeup.c @@ -113,7 +113,6 @@ void wakeup_source_drop(struct wakeup_so if (!ws) return;
- del_timer_sync(&ws->timer); __pm_relax(ws); } EXPORT_SYMBOL_GPL(wakeup_source_drop); @@ -201,6 +200,13 @@ void wakeup_source_remove(struct wakeup_ list_del_rcu(&ws->entry); spin_unlock_irqrestore(&events_lock, flags); synchronize_srcu(&wakeup_srcu); + + del_timer_sync(&ws->timer); + /* + * Clear timer.function to make wakeup_source_not_registered() treat + * this wakeup source as not registered. + */ + ws->timer.function = NULL; } EXPORT_SYMBOL_GPL(wakeup_source_remove);