gpu: host1x: Detach driver on unregister
authorThierry Reding <treding@nvidia.com>
Wed, 8 Apr 2020 17:38:02 +0000 (19:38 +0200)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Thu, 16 Jul 2020 06:13:12 +0000 (08:13 +0200)
commitf9f34d8fb0a90f599b6287686340d0569a201fd7
treedaf028f46e14f207702c2c50535bcb6d316ff8ec
parentceea8871fc9a6af90ea1f1595b9368a5595d61d4
gpu: host1x: Detach driver on unregister

[ Upstream commit d9a0a05bf8c76e6dc79230669a8b5d685b168c30 ]

Currently when a host1x device driver is unregistered, it is not
detached from the host1x controller, which means that the device
will stay around and when the driver is registered again, it may
bind to the old, stale device rather than the new one that was
created from scratch upon driver registration. This in turn can
cause various weird crashes within the driver core because it is
confronted with a device that was already deleted.

Fix this by detaching the driver from the host1x controller when
it is unregistered. This ensures that the deleted device also is
no longer present in the device list that drivers will bind to.

Reported-by: Sowjanya Komatineni <skomatineni@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Tested-by: Sowjanya Komatineni <skomatineni@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
drivers/gpu/host1x/bus.c