Patch "drm/vmwgfx: Unreserve BO on error" has been added to the 6.12-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    drm/vmwgfx: Unreserve BO on error

to the 6.12-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     drm-vmwgfx-unreserve-bo-on-error.patch
and it can be found in the queue-6.12 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit f1c0d4f64ee64a22cf5f861c2714457f2ed0948e
Author: Ian Forbes <ian.forbes@xxxxxxxxxxxx>
Date:   Tue Dec 10 13:55:35 2024 -0600

    drm/vmwgfx: Unreserve BO on error
    
    [ Upstream commit cb343ded122e0bf41e4b2a9f89386296451be109 ]
    
    Unlock BOs in reverse order.
    Add an acquire context so that lockdep doesn't complain.
    
    Fixes: d6667f0ddf46 ("drm/vmwgfx: Fix handling of dumb buffers")
    Signed-off-by: Ian Forbes <ian.forbes@xxxxxxxxxxxx>
    Signed-off-by: Zack Rusin <zack.rusin@xxxxxxxxxxxx>
    Link: https://patchwork.freedesktop.org/patch/msgid/20241210195535.2074918-1-ian.forbes@xxxxxxxxxxxx
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c b/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c
index 10d596cb4b402..5f99f7437ae61 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c
@@ -750,6 +750,7 @@ vmw_du_cursor_plane_atomic_update(struct drm_plane *plane,
 	struct vmw_plane_state *old_vps = vmw_plane_state_to_vps(old_state);
 	struct vmw_bo *old_bo = NULL;
 	struct vmw_bo *new_bo = NULL;
+	struct ww_acquire_ctx ctx;
 	s32 hotspot_x, hotspot_y;
 	int ret;
 
@@ -769,9 +770,11 @@ vmw_du_cursor_plane_atomic_update(struct drm_plane *plane,
 	if (du->cursor_surface)
 		du->cursor_age = du->cursor_surface->snooper.age;
 
+	ww_acquire_init(&ctx, &reservation_ww_class);
+
 	if (!vmw_user_object_is_null(&old_vps->uo)) {
 		old_bo = vmw_user_object_buffer(&old_vps->uo);
-		ret = ttm_bo_reserve(&old_bo->tbo, false, false, NULL);
+		ret = ttm_bo_reserve(&old_bo->tbo, false, false, &ctx);
 		if (ret != 0)
 			return;
 	}
@@ -779,9 +782,14 @@ vmw_du_cursor_plane_atomic_update(struct drm_plane *plane,
 	if (!vmw_user_object_is_null(&vps->uo)) {
 		new_bo = vmw_user_object_buffer(&vps->uo);
 		if (old_bo != new_bo) {
-			ret = ttm_bo_reserve(&new_bo->tbo, false, false, NULL);
-			if (ret != 0)
+			ret = ttm_bo_reserve(&new_bo->tbo, false, false, &ctx);
+			if (ret != 0) {
+				if (old_bo) {
+					ttm_bo_unreserve(&old_bo->tbo);
+					ww_acquire_fini(&ctx);
+				}
 				return;
+			}
 		} else {
 			new_bo = NULL;
 		}
@@ -803,10 +811,12 @@ vmw_du_cursor_plane_atomic_update(struct drm_plane *plane,
 						hotspot_x, hotspot_y);
 	}
 
-	if (old_bo)
-		ttm_bo_unreserve(&old_bo->tbo);
 	if (new_bo)
 		ttm_bo_unreserve(&new_bo->tbo);
+	if (old_bo)
+		ttm_bo_unreserve(&old_bo->tbo);
+
+	ww_acquire_fini(&ctx);
 
 	du->cursor_x = new_state->crtc_x + du->set_gui_x;
 	du->cursor_y = new_state->crtc_y + du->set_gui_y;