From mboxrd@z Thu Jan 1 00:00:00 1970 From: daniel.lezcano@linaro.org (Daniel Lezcano) Date: Wed, 28 Oct 2015 14:11:29 +0100 Subject: [PATCH 4/8] clocksource/drivers/prima2: Prevent ftrace recursion In-Reply-To: <1446037894-22601-1-git-send-email-daniel.lezcano@linaro.org> References: <5630C947.4020706@linaro.org> <1446037894-22601-1-git-send-email-daniel.lezcano@linaro.org> Message-ID: <1446037894-22601-4-git-send-email-daniel.lezcano@linaro.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org From: Jisheng Zhang Currently prima2 timer can be used as a scheduler clock. We properly marked sirfsoc_read_sched_clock() as notrace but we then call another function sirfsoc_timer_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 sirfsoc_timer_read() function. Signed-off-by: Jisheng Zhang Signed-off-by: Daniel Lezcano --- drivers/clocksource/timer-prima2.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/clocksource/timer-prima2.c b/drivers/clocksource/timer-prima2.c index 78de982..2854c66 100644 --- a/drivers/clocksource/timer-prima2.c +++ b/drivers/clocksource/timer-prima2.c @@ -73,7 +73,7 @@ static irqreturn_t sirfsoc_timer_interrupt(int irq, void *dev_id) } /* read 64-bit timer counter */ -static cycle_t sirfsoc_timer_read(struct clocksource *cs) +static cycle_t notrace sirfsoc_timer_read(struct clocksource *cs) { u64 cycles; -- 1.9.1