[PATCH 6.12 148/218] drm/ast: Fix comment on modeset lock

[PATCH 6.12 148/218] drm/ast: Fix comment on modeset lock

[Greg Kroah-Hartman]

6.12-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Thomas Zimmermann <tzimmermann@suse.de>

commit 7cce65f3789e04c0f7668a66563e680d81d54493 upstream.

The ast driver protects the commit tail against concurrent reads
of the display modes by acquiring a lock. The comment is misleading
as the lock is not released in atomic_flush, but at the end of the
commit-tail helper. Rewrite the comment.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Fixes: 1fe182154984 ("drm/ast: Acquire I/O-register lock in atomic_commit_tail function")
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Jocelyn Falempe <jfalempe@redhat.com>
Cc: Dave Airlie <airlied@redhat.com>
Cc: dri-devel@lists.freedesktop.org
Cc: <stable@vger.kernel.org> # v6.2+
Reviewed-by: Jocelyn Falempe <jfalempe@redhat.com>
Link: https://lore.kernel.org/r/20250324094520.192974-2-tzimmermann@suse.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/gpu/drm/ast/ast_mode.c |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

--- a/drivers/gpu/drm/ast/ast_mode.c
+++ b/drivers/gpu/drm/ast/ast_mode.c
@@ -1319,9 +1319,9 @@ static void ast_mode_config_helper_atomi
 
 	/*
 	 * Concurrent operations could possibly trigger a call to
-	 * drm_connector_helper_funcs.get_modes by trying to read the
-	 * display modes. Protect access to I/O registers by acquiring
-	 * the I/O-register lock. Released in atomic_flush().
+	 * drm_connector_helper_funcs.get_modes by reading the display
+	 * modes. Protect access to registers by acquiring the modeset
+	 * lock.
 	 */
 	mutex_lock(&ast->modeset_lock);
 	drm_atomic_helper_commit_tail(state);

[PATCH 6.12 153/218] drm/udl: Unregister device before cleaning up on disconnect

[Greg Kroah-Hartman]

6.12-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Thomas Zimmermann <tzimmermann@suse.de>

commit ff9cb6d2035c586ea7c8f1754d4409eec7a2d26d upstream.

Disconnecting a DisplayLink device results in the following kernel
error messages

[   93.041748] [drm:udl_urb_completion [udl]] *ERROR* udl_urb_completion - nonzero write bulk status received: -115
[   93.055299] [drm:udl_submit_urb [udl]] *ERROR* usb_submit_urb error fffffffe
[   93.065363] [drm:udl_urb_completion [udl]] *ERROR* udl_urb_completion - nonzero write bulk status received: -115
[   93.078207] [drm:udl_submit_urb [udl]] *ERROR* usb_submit_urb error fffffffe

coming from KMS poll helpers. Shutting down poll helpers runs them
one final time when the USB device is already gone.

Run drm_dev_unplug() first in udl's USB disconnect handler. Udl's
polling code already handles disconnects gracefully if the device has
been marked as unplugged.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Fixes: b1a981bd5576 ("drm/udl: drop drm_driver.release hook")
Cc: dri-devel@lists.freedesktop.org
Cc: <stable@vger.kernel.org> # v5.8+
Reviewed-by: Patrik Jakobsson <patrik.r.jakobsson@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20250303145604.62962-2-tzimmermann@suse.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/gpu/drm/udl/udl_drv.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/gpu/drm/udl/udl_drv.c
+++ b/drivers/gpu/drm/udl/udl_drv.c
@@ -126,9 +126,9 @@ static void udl_usb_disconnect(struct us
 {
 	struct drm_device *dev = usb_get_intfdata(interface);
 
+	drm_dev_unplug(dev);
 	drm_kms_helper_poll_fini(dev);
 	udl_drop_usb(dev);
-	drm_dev_unplug(dev);
 }
 
 /*