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| author | Alexandre Belloni <alexandre.belloni@free-electrons.com> | 2017-08-21 00:01:46 +0200 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2017-08-31 21:36:45 +0200 |
| commit | 51218298a25e6942957c5595f2abf130d47d5df9 (patch) | |
| tree | 235c2bc0f868679108179df74bb2b660719bda87 /kernel/time | |
| parent | bc30658eff39c5bb562174fcf93618ab6a7afe88 (diff) | |
| download | linux-51218298a25e6942957c5595f2abf130d47d5df9.tar.bz2 | |
alarmtimer: Ensure RTC module is not unloaded
When registering the rtc device to be used to handle alarm timers,
get_device is used to ensure the device doesn't go away but the module can
still be unloaded.
Call try_module_get to ensure the rtc driver will not go away.
Reported-and-tested-by: Michal Simek <monstr@monstr.eu>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: John Stultz <john.stultz@linaro.org>
Cc: Stephen Boyd <sboyd@codeaurora.org>
Link: http://lkml.kernel.org/r/20170820220146.30969-1-alexandre.belloni@free-electrons.com
Diffstat (limited to 'kernel/time')
| -rw-r--r-- | kernel/time/alarmtimer.c | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c index 73a2b476e59f..ec09ce9a6012 100644 --- a/kernel/time/alarmtimer.c +++ b/kernel/time/alarmtimer.c @@ -28,6 +28,7 @@ #include <linux/workqueue.h> #include <linux/freezer.h> #include <linux/compat.h> +#include <linux/module.h> #include "posix-timers.h" @@ -103,6 +104,11 @@ static int alarmtimer_rtc_add_device(struct device *dev, spin_lock_irqsave(&rtcdev_lock, flags); if (!rtcdev) { + if (!try_module_get(rtc->owner)) { + spin_unlock_irqrestore(&rtcdev_lock, flags); + return -1; + } + rtcdev = rtc; /* hold a reference so it doesn't go away */ get_device(dev); |