diff options
author | Dan Carpenter <error27@gmail.com> | 2010-05-24 14:33:49 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2010-05-25 08:07:08 -0700 |
commit | 6ba8bcd457d9fc793ac9435aa2e4138f571d4ec5 (patch) | |
tree | d562dedc503e3f67d80517494b53afa651418bb8 /drivers/rtc | |
parent | 72cc8e51cfdde9007adab7d841ac4113b05b2c56 (diff) | |
download | blackbird-op-linux-6ba8bcd457d9fc793ac9435aa2e4138f571d4ec5.tar.gz blackbird-op-linux-6ba8bcd457d9fc793ac9435aa2e4138f571d4ec5.zip |
rtc-cmos: do dev_set_drvdata() earlier in the initialization
The bug is an oops when dev_get_drvdata() returned null in
cmos_update_irq_enable(). The call tree looks like this:
rtc_dev_ioctl()
=> rtc_update_irq_enable()
=> cmos_update_irq_enable()
It's caused by a race condition in the module initialization. It is
rtc_device_register() which makes the ioctl operations live so I moved
the call to dev_set_drvdata() before the call to rtc_device_register().
Addresses https://bugzilla.kernel.org/show_bug.cgi?id=15963
Reported-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Dan Carpenter <error27@gmail.com>
Tested-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Paul Gortmaker <p_gortmaker@yahoo.com>
Cc: Malte Schroder <maltesch@gmx.de>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Herton Ronaldo Krzesinski <herton@mandriva.com.br>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'drivers/rtc')
-rw-r--r-- | drivers/rtc/rtc-cmos.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/drivers/rtc/rtc-cmos.c b/drivers/rtc/rtc-cmos.c index 96e8e70fbf1e..11b8ea29d2b7 100644 --- a/drivers/rtc/rtc-cmos.c +++ b/drivers/rtc/rtc-cmos.c @@ -719,6 +719,9 @@ cmos_do_probe(struct device *dev, struct resource *ports, int rtc_irq) } } + cmos_rtc.dev = dev; + dev_set_drvdata(dev, &cmos_rtc); + cmos_rtc.rtc = rtc_device_register(driver_name, dev, &cmos_rtc_ops, THIS_MODULE); if (IS_ERR(cmos_rtc.rtc)) { @@ -726,8 +729,6 @@ cmos_do_probe(struct device *dev, struct resource *ports, int rtc_irq) goto cleanup0; } - cmos_rtc.dev = dev; - dev_set_drvdata(dev, &cmos_rtc); rename_region(ports, dev_name(&cmos_rtc.rtc->dev)); spin_lock_irq(&rtc_lock); |