timekeeping: Prevent oops when GENERIC_TIME=n
Aaro Koskinen reported an issue in kernel.org bugzilla #15366, where
on non-GENERIC_TIME systems, accessing
/sys/devices/system/clocksource/clocksource0/current_clocksource
results in an oops.
It seems the timekeeper/clocksource rework missed initializing the
curr_clocksource value in the !GENERIC_TIME case.
Thanks to Aaro for reporting and diagnosing the issue as well as
testing the fix!
Reported-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Signed-off-by: John Stultz <johnstul@us.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: stable@kernel.org
LKML-Reference: <1267475683.4216.61.camel@localhost.localdomain>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c
index 1f663d2..1f5dde6 100644
--- a/kernel/time/clocksource.c
+++ b/kernel/time/clocksource.c
@@ -592,6 +592,10 @@
*/
static int __init clocksource_done_booting(void)
{
+ mutex_lock(&clocksource_mutex);
+ curr_clocksource = clocksource_default_clock();
+ mutex_unlock(&clocksource_mutex);
+
finished_booting = 1;
/*