tree 72ebdfa1d65066a6cd5361ee605a48e2dfcda4b2
parent 1fe70e963028f34ba5e32488a7870ff4b410b19b
author Jonathan Nieder <jrnieder@gmail.com> 1304242196 -0300
committer Mauro Carvalho Chehab <mchehab@redhat.com> 1305894577 -0300

[media] cx88: hold device lock during sub-driver initialization

cx8802_blackbird_probe makes a device node for the mpeg sub-device
before it has been added to dev->drvlist.  If the device is opened
during that time, the open succeeds but request_acquire cannot be
called, so the reference count remains zero.  Later, when the device
is closed, the reference count becomes negative --- uh oh.

Close the race by holding core->lock during probe and not releasing
until the device is in drvlist and initialization finished.
Previously the BKL prevented this race.

Reported-by: Andreas Huber <hobrom@gmx.at>
Tested-by: Andi Huber <hobrom@gmx.at>
Tested-by: Marlon de Boer <marlon@hyves.nl>
Cc: stable@kernel.org
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>