[PATCH drm-misc-next v2 5/9] drm/arm/malidp: use drm_dev_unplug()

From: Danilo Krummrich
Date: Sat Oct 01 2022 - 12:40:35 EST

When the driver is unbound, there might still be users in userspace
having an open fd and are calling into the driver.

While this is fine for drm managed resources, it is not for resources
bound to the device/driver lifecycle, e.g. clocks or MMIO mappings.

To prevent use-after-free issues we need to protect those resources with
drm_dev_enter() and drm_dev_exit(). This does only work if we indicate
that the drm device was unplugged, hence use drm_dev_unplug() instead of

Protecting the particular resources with drm_dev_enter()/drm_dev_exit()
is handled by subsequent patches.

Signed-off-by: Danilo Krummrich <dakr@xxxxxxxxxx>
drivers/gpu/drm/arm/malidp_drv.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/arm/malidp_drv.c b/drivers/gpu/drm/arm/malidp_drv.c
index 678c5b0d8014..aedd30f5f451 100644
--- a/drivers/gpu/drm/arm/malidp_drv.c
+++ b/drivers/gpu/drm/arm/malidp_drv.c
@@ -893,7 +893,7 @@ static void malidp_unbind(struct device *dev)
struct malidp_drm *malidp = drm_to_malidp(drm);
struct malidp_hw_device *hwdev = malidp->dev;

- drm_dev_unregister(drm);
+ drm_dev_unplug(drm);