linux-kernel - [PATCH] drm/udl: Increase get urb timeout for modeset

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-Id: <20251105083037.237925-1-oushixiong1025@163.com>
Date: Wed,  5 Nov 2025 16:30:37 +0800
From: oushixiong1025@....com
To: Dave Airlie <airlied@...hat.com>
Cc: Sean Paul <sean@...rly.run>,
	Thomas Zimmermann <tzimmermann@...e.de>,
	Maarten Lankhorst <maarten.lankhorst@...ux.intel.com>,
	Maxime Ripard <mripard@...nel.org>,
	David Airlie <airlied@...il.com>,
	Simona Vetter <simona@...ll.ch>,
	dri-devel@...ts.freedesktop.org,
	linux-kernel@...r.kernel.org,
	Shixiong Ou <oushixiong@...inos.cn>
Subject: [PATCH] drm/udl: Increase get urb timeout for modeset

From: Shixiong Ou <oushixiong@...inos.cn>

[WHY]
There is a situation where udl_handle_damage() was running successfully
but the screen was black. it was because udl_crtc_helper_atomic_enable() failed,
and there were no error messages.

[HOW]
The priority for mode settings needs to be higher than damage handle, requiring
a higher success rate than ordinary operations.
Increase get urb timeout for modeset.

Signed-off-by: Shixiong Ou <oushixiong@...inos.cn>
---
 drivers/gpu/drm/udl/udl_drv.h      |  5 ++++-
 drivers/gpu/drm/udl/udl_main.c     |  5 ++---
 drivers/gpu/drm/udl/udl_modeset.c  | 11 +++++++----
 drivers/gpu/drm/udl/udl_transfer.c |  2 +-
 4 files changed, 14 insertions(+), 9 deletions(-)

diff --git a/drivers/gpu/drm/udl/udl_drv.h b/drivers/gpu/drm/udl/udl_drv.h
index 145bb95ccc48..38b3bdf1ae4a 100644
--- a/drivers/gpu/drm/udl/udl_drv.h
+++ b/drivers/gpu/drm/udl/udl_drv.h
@@ -31,6 +31,9 @@ struct drm_mode_create_dumb;
 #define DRIVER_MINOR		0
 #define DRIVER_PATCHLEVEL	1
 
+#define GET_URB_TIMEOUT	HZ
+#define MODESET_GET_URB_TIMEOUT	(HZ*2)
+
 struct udl_device;
 
 struct urb_node {
@@ -72,7 +75,7 @@ static inline struct usb_device *udl_to_usb_device(struct udl_device *udl)
 int udl_modeset_init(struct udl_device *udl);
 struct drm_connector *udl_connector_init(struct drm_device *dev);
 
-struct urb *udl_get_urb(struct udl_device *udl);
+struct urb *udl_get_urb(struct udl_device *udl, long timeout);
 
 int udl_submit_urb(struct udl_device *udl, struct urb *urb, size_t len);
 void udl_sync_pending_urbs(struct udl_device *udl);
diff --git a/drivers/gpu/drm/udl/udl_main.c b/drivers/gpu/drm/udl/udl_main.c
index bc58991a6f14..891996f0f74b 100644
--- a/drivers/gpu/drm/udl/udl_main.c
+++ b/drivers/gpu/drm/udl/udl_main.c
@@ -285,13 +285,12 @@ static struct urb *udl_get_urb_locked(struct udl_device *udl, long timeout)
 	return unode->urb;
 }
 
-#define GET_URB_TIMEOUT	HZ
-struct urb *udl_get_urb(struct udl_device *udl)
+struct urb *udl_get_urb(struct udl_device *udl, long timeout)
 {
 	struct urb *urb;
 
 	spin_lock_irq(&udl->urbs.lock);
-	urb = udl_get_urb_locked(udl, GET_URB_TIMEOUT);
+	urb = udl_get_urb_locked(udl, timeout);
 	spin_unlock_irq(&udl->urbs.lock);
 	return urb;
 }
diff --git a/drivers/gpu/drm/udl/udl_modeset.c b/drivers/gpu/drm/udl/udl_modeset.c
index 231e829bd709..6adca5e3e471 100644
--- a/drivers/gpu/drm/udl/udl_modeset.c
+++ b/drivers/gpu/drm/udl/udl_modeset.c
@@ -21,6 +21,7 @@
 #include <drm/drm_gem_framebuffer_helper.h>
 #include <drm/drm_gem_shmem_helper.h>
 #include <drm/drm_modeset_helper_vtables.h>
+#include <drm/drm_print.h>
 #include <drm/drm_probe_helper.h>
 #include <drm/drm_vblank.h>
 
@@ -217,7 +218,7 @@ static int udl_handle_damage(struct drm_framebuffer *fb,
 		return ret;
 	log_bpp = ret;
 
-	urb = udl_get_urb(udl);
+	urb = udl_get_urb(udl, GET_URB_TIMEOUT);
 	if (!urb)
 		return -ENOMEM;
 	cmd = urb->transfer_buffer;
@@ -341,9 +342,11 @@ static void udl_crtc_helper_atomic_enable(struct drm_crtc *crtc, struct drm_atom
 	if (!drm_dev_enter(dev, &idx))
 		return;
 
-	urb = udl_get_urb(udl);
-	if (!urb)
+	urb = udl_get_urb(udl, MODESET_GET_URB_TIMEOUT);
+	if (!urb) {
+		DRM_ERROR("Udl get urb failed when enabling crtc");
 		goto out;
+	}
 
 	buf = (char *)urb->transfer_buffer;
 	buf = udl_vidreg_lock(buf);
@@ -374,7 +377,7 @@ static void udl_crtc_helper_atomic_disable(struct drm_crtc *crtc, struct drm_ato
 	if (!drm_dev_enter(dev, &idx))
 		return;
 
-	urb = udl_get_urb(udl);
+	urb = udl_get_urb(udl, MODESET_GET_URB_TIMEOUT);
 	if (!urb)
 		goto out;
 
diff --git a/drivers/gpu/drm/udl/udl_transfer.c b/drivers/gpu/drm/udl/udl_transfer.c
index 7d670b3a5293..858b47522d78 100644
--- a/drivers/gpu/drm/udl/udl_transfer.c
+++ b/drivers/gpu/drm/udl/udl_transfer.c
@@ -202,7 +202,7 @@ int udl_render_hline(struct udl_device *udl, int log_bpp, struct urb **urb_ptr,
 			int ret = udl_submit_urb(udl, urb, len);
 			if (ret)
 				return ret;
-			urb = udl_get_urb(udl);
+			urb = udl_get_urb(udl, GET_URB_TIMEOUT);
 			if (!urb)
 				return -EAGAIN;
 			*urb_ptr = urb;
-- 
2.25.1