GitHub-Mirror/Star64_linux
2
0
Fork 0
mirror of https://github.com/Fishwaldo/Star64_linux.git synced 2025-06-22 22:51:37 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions

RTC: Fix early irqs caused by calling rtc_set_alarm too early

Browse source 
When we register an rtc device at boot, we read the alarm value
in hardware and set the rtc device's aie_timer to that value.

The initial method to do this was to simply call rtc_set_alarm()
with the value read from hardware. However, this may cause problems
as rtc_set_alarm may enable interupts, and the RTC alarm might fire,
which can cause invalid pointer dereferencing since the RTC registration
is not complete.

This patch solves the issue by initializing the rtc_device.aie_timer
y hand via rtc_initialize_alarm(). This avoids any calls to the RTC
hardware which might enable interrupts too early.

CC: Thomas Gleixner <tglx@linutronix.de>
CC: Alessandro Zummo <a.zummo@towertech.it>
Reported-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Tested-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
This commit is contained in:
John Stultz 2011-03-29 18:00:27 -07:00
parent 0ce790e7d7
commit f6d5b33125
3 changed files with 29 additions and 1 deletions
Download patch file Download diff file Expand all files Collapse all files

2
drivers/rtc/class.c
View file

@ -171,7 +171,7 @@ struct rtc_device *rtc_device_register(const char *name, struct device *dev,
err = __rtc_read_alarm(rtc, &alrm);
if (!err && !rtc_valid_tm(&alrm.time))
rtc_set_alarm(rtc, &alrm);
rtc_initialize_alarm(rtc, &alrm);
strlcpy(rtc->name, name, RTC_DEVICE_NAME_SIZE);
dev_set_name(&rtc->dev, "rtc%d", id);