From: jszhang@marvell.com (Jisheng Zhang)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH] clocksource/drivers/ti-32k: Prevent ftrace recursion
Date: Thu, 22 Sep 2016 15:56:21 +0800 [thread overview]
Message-ID: <20160922075621.3725-1-jszhang@marvell.com> (raw)
Currently ti-32k can be used as a scheduler clock. We properly marked
omap_32k_read_sched_clock() as notrace but we then call another
function ti_32k_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 ti_32k_read_cycles()
function.
Signed-off-by: Jisheng Zhang <jszhang@marvell.com>
---
drivers/clocksource/timer-ti-32k.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/clocksource/timer-ti-32k.c b/drivers/clocksource/timer-ti-32k.c
index 92b7e39..cf5b14e 100644
--- a/drivers/clocksource/timer-ti-32k.c
+++ b/drivers/clocksource/timer-ti-32k.c
@@ -65,7 +65,7 @@ static inline struct ti_32k *to_ti_32k(struct clocksource *cs)
return container_of(cs, struct ti_32k, cs);
}
-static cycle_t ti_32k_read_cycles(struct clocksource *cs)
+static cycle_t notrace ti_32k_read_cycles(struct clocksource *cs)
{
struct ti_32k *ti = to_ti_32k(cs);
--
2.9.3
next reply other threads:[~2016-09-22 7:56 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-09-22 7:56 Jisheng Zhang [this message]
2016-09-22 13:58 ` [PATCH] clocksource/drivers/ti-32k: Prevent ftrace recursion Thomas Gleixner
2016-09-22 14:29 ` Steven Rostedt
2016-09-23 2:04 ` Jisheng Zhang
2016-09-23 2:45 ` Steven Rostedt
2016-09-23 2:48 ` Jisheng Zhang
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