From: Jisheng Zhang Date: Tue, 20 Oct 2015 08:02:35 +0000 (+0800) Subject: clocksource/drivers/samsung_pwm_timer: Prevent ftrace recursion X-Git-Url: http://drtracing.org/?a=commitdiff_plain;h=b8725dab66f0b2d57affb33a7f6ca094d9f1f8dd;p=deliverable%2Flinux.git clocksource/drivers/samsung_pwm_timer: Prevent ftrace recursion Currently samsung_pwm_timer can be used as a scheduler clock. We properly marked samsung_read_sched_clock() as notrace but we then call another function samsung_clocksource_read() that _wasn't_ notrace. Having a traceable function in the sched_clock() path leads to a recursion within ftrace and a kernel crash. Fix this by adding notrace attribute to the samsung_clocksource_read() function. Signed-off-by: Jisheng Zhang Signed-off-by: Daniel Lezcano --- diff --git a/drivers/clocksource/samsung_pwm_timer.c b/drivers/clocksource/samsung_pwm_timer.c index bc90e13338cc..9502bc4c3f6d 100644 --- a/drivers/clocksource/samsung_pwm_timer.c +++ b/drivers/clocksource/samsung_pwm_timer.c @@ -307,7 +307,7 @@ static void samsung_clocksource_resume(struct clocksource *cs) samsung_time_start(pwm.source_id, true); } -static cycle_t samsung_clocksource_read(struct clocksource *c) +static cycle_t notrace samsung_clocksource_read(struct clocksource *c) { return ~readl_relaxed(pwm.source_reg); }