diff options
| author |   Tomas Winkler <tomas.winkler@intel.com> | 2017-03-05 21:40:41 +0200 |
|---|---|---|
| committer |   Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-03-16 10:47:53 +0900 |
| commit | a733ded50b6ea846200073e7381a302df71e13b3 (patch) | |
| tree | c607f1208e4cd54539e099d5dab4772e56e1beb5 /drivers/misc | |
| parent | Merge tag 'stm-fixes-for-greg-20170315' of git://git.kernel.org/pub/scm/linux/kernel/git/ash/stm into char-misc-linus (diff) | |
| download | linux-dev-a733ded50b6ea846200073e7381a302df71e13b3.tar.xz linux-dev-a733ded50b6ea846200073e7381a302df71e13b3.zip | |
mei: fix deadlock on mei reset
This patch fixes 'mei: synchronize irq before initiating a reset'
The patch had introduced a deadlock between irq thread and mei_reset()
as they are both holding the same device lock.
---> device_lock:
mei_reset()
<---- interrupt thread
device_lock
---> synchornize_irq()
wait on interrupt thread == (dead lock)
The fix is to call synchronize_irq
prior to call locked mei_reset function.
Cc: <stable@vger.kernel.org> #4.10+
Fixes: f302bb0de6ac (mei: synchronize irq before initiating a reset)
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/misc')
| -rw-r--r-- | drivers/misc/mei/init.c | 8 |
1 files changed, 6 insertions, 2 deletions
diff --git a/drivers/misc/mei/init.c b/drivers/misc/mei/init.c index cfb1cdf176fa..13c55b8f9261 100644 --- a/drivers/misc/mei/init.c +++ b/drivers/misc/mei/init.c @@ -124,8 +124,6 @@ int mei_reset(struct mei_device *dev) mei_clear_interrupts(dev); - mei_synchronize_irq(dev); - /* we're already in reset, cancel the init timer * if the reset was called due the hbm protocol error * we need to call it before hw start @@ -304,6 +302,9 @@ static void mei_reset_work(struct work_struct *work) container_of(work, struct mei_device, reset_work); int ret; + mei_clear_interrupts(dev); + mei_synchronize_irq(dev); + mutex_lock(&dev->device_lock); ret = mei_reset(dev); @@ -328,6 +329,9 @@ void mei_stop(struct mei_device *dev) mei_cancel_work(dev); + mei_clear_interrupts(dev); + mei_synchronize_irq(dev); + mutex_lock(&dev->device_lock); dev->dev_state = MEI_DEV_POWER_DOWN; |