diff options
author | Tomas Winkler <tomas.winkler@intel.com> | 2015-07-08 00:22:03 +0300 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2015-07-08 01:04:12 +0300 |
commit | 4f273959b850569253299987eee611927f048de7 (patch) | |
tree | 384abc27b134c3570ad8bcc7b6461e4128e7ed6a /drivers/misc | |
parent | c7e9ad7da219cf3f8a7cc45eb1c02fdd91199e8d (diff) | |
download | linux-4f273959b850569253299987eee611927f048de7.tar.xz |
mei: nfc: fix deadlock on shutdown/suspend path
In function mei_nfc_host_exit mei_cl_remove_device cannot be called
under the device mutex as device removing flow invokes the device driver
remove handler that calls in turn to mei_cl_disable_device which
naturally acquires the device mutex.
Also remove mei_cl_bus_remove_devices which has the same issue, but is
never executed as currently the only device on the mei client bus is NFC
and a new device cannot be easily added till the bus revamp is
completed.
This fixes regression caused by commit be9b720a0ccb ("mei_phy: move all
nfc logic from mei driver to nfc")
Prior to this change the nfc driver remove handler called to no-op
disable function while actual nfc device was disabled directly from the
mei driver.
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Samuel Ortiz <sameo@linux.intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'drivers/misc')
-rw-r--r-- | drivers/misc/mei/bus.c | 16 | ||||
-rw-r--r-- | drivers/misc/mei/init.c | 2 | ||||
-rw-r--r-- | drivers/misc/mei/nfc.c | 3 |
3 files changed, 2 insertions, 19 deletions
diff --git a/drivers/misc/mei/bus.c b/drivers/misc/mei/bus.c index 357b6ae4d207..458aa5a09c52 100644 --- a/drivers/misc/mei/bus.c +++ b/drivers/misc/mei/bus.c @@ -552,22 +552,6 @@ void mei_cl_bus_rx_event(struct mei_cl *cl) schedule_work(&device->event_work); } -void mei_cl_bus_remove_devices(struct mei_device *dev) -{ - struct mei_cl *cl, *next; - - mutex_lock(&dev->device_lock); - list_for_each_entry_safe(cl, next, &dev->device_list, device_link) { - if (cl->device) - mei_cl_remove_device(cl->device); - - list_del(&cl->device_link); - mei_cl_unlink(cl); - kfree(cl); - } - mutex_unlock(&dev->device_lock); -} - int __init mei_cl_bus_init(void) { return bus_register(&mei_cl_bus_type); diff --git a/drivers/misc/mei/init.c b/drivers/misc/mei/init.c index 94514b2c7a50..00c3865ca3b1 100644 --- a/drivers/misc/mei/init.c +++ b/drivers/misc/mei/init.c @@ -333,8 +333,6 @@ void mei_stop(struct mei_device *dev) mei_nfc_host_exit(dev); - mei_cl_bus_remove_devices(dev); - mutex_lock(&dev->device_lock); mei_wd_stop(dev); diff --git a/drivers/misc/mei/nfc.c b/drivers/misc/mei/nfc.c index b983c4ecad38..290ef3037437 100644 --- a/drivers/misc/mei/nfc.c +++ b/drivers/misc/mei/nfc.c @@ -402,11 +402,12 @@ void mei_nfc_host_exit(struct mei_device *dev) cldev->priv_data = NULL; - mutex_lock(&dev->device_lock); /* Need to remove the device here * since mei_nfc_free will unlink the clients */ mei_cl_remove_device(cldev); + + mutex_lock(&dev->device_lock); mei_nfc_free(ndev); mutex_unlock(&dev->device_lock); } |