From 7861144b8cb217634d738e94a748deeae139a1e2 Mon Sep 17 00:00:00 2001 From: Andrew Morton Date: Fri, 18 Apr 2014 15:07:12 -0700 Subject: kernel/watchdog.c:touch_softlockup_watchdog(): use raw_cpu_write() Fix: BUG: using __this_cpu_write() in preemptible [00000000] code: systemd-udevd/497 caller is __this_cpu_preempt_check+0x13/0x20 CPU: 3 PID: 497 Comm: systemd-udevd Tainted: G W 3.15.0-rc1 #9 Hardware name: Hewlett-Packard HP EliteBook 8470p/179B, BIOS 68ICF Ver. F.02 04/27/2012 Call Trace: check_preemption_disabled+0xe1/0xf0 __this_cpu_preempt_check+0x13/0x20 touch_nmi_watchdog+0x28/0x40 Reported-by: Luis Henriques Tested-by: Luis Henriques Cc: Eric Piel Cc: Robert Moore Cc: Lv Zheng Cc: "Rafael J. Wysocki" Cc: Len Brown Cc: Christoph Lameter Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/watchdog.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/kernel/watchdog.c b/kernel/watchdog.c index e90089fd78e..516203e665f 100644 --- a/kernel/watchdog.c +++ b/kernel/watchdog.c @@ -138,7 +138,11 @@ static void __touch_watchdog(void) void touch_softlockup_watchdog(void) { - __this_cpu_write(watchdog_touch_ts, 0); + /* + * Preemption can be enabled. It doesn't matter which CPU's timestamp + * gets zeroed here, so use the raw_ operation. + */ + raw_cpu_write(watchdog_touch_ts, 0); } EXPORT_SYMBOL(touch_softlockup_watchdog); -- cgit v1.2.3-70-g09d2