From f8af0e9c644caf64d0f42dce816c18346c744a9f Mon Sep 17 00:00:00 2001 From: Jisheng Zhang Date: Tue, 20 Oct 2015 16:02:36 +0800 Subject: [PATCH] clocksource/drivers/pistachio: Prevent ftrace recursion Currently pistachio can be used as a scheduler clock. We properly marked pistachio_read_sched_clock() as notrace but we then call another function pistachio_clocksource_read_cycles() 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 pistachio_clocksource_read_cycles() function. Signed-off-by: Jisheng Zhang Signed-off-by: Daniel Lezcano --- drivers/clocksource/time-pistachio.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/clocksource/time-pistachio.c b/drivers/clocksource/time-pistachio.c index 18d4266c2986..bba679900054 100644 --- a/drivers/clocksource/time-pistachio.c +++ b/drivers/clocksource/time-pistachio.c @@ -67,7 +67,8 @@ static inline void gpt_writel(void __iomem *base, u32 value, u32 offset, writel(value, base + 0x20 * gpt_id + offset); } -static cycle_t pistachio_clocksource_read_cycles(struct clocksource *cs) +static cycle_t notrace +pistachio_clocksource_read_cycles(struct clocksource *cs) { struct pistachio_clocksource *pcs = to_pistachio_clocksource(cs); u32 counter, overflw; -- 2.20.1