[PATCH xf86-video-amdgpu 1/3] Call drmmode_crtc_scanout_create in drmmode_crtc_shadow_allocate as well

[Michel Dänzer]

From: Michel Dänzer <michel.daenzer at amd.com>

Calling drmmode_crtc_scanout_allocate in drmmode_crtc_shadow_allocate
resulted in drmmode_crtc_scanout_create called from
drmmode_crtc_shadow_create passing an uninitialized pitch value to
drmmode_create_bo_pixmap.

Fixes issues such as failure to allocate the scanout pixmap or visual
corruption and GPUVM faults when attempting to use rotation with Xorg
<1.19.

Bugzilla: https://bugs.freedesktop.org/99916
Fixes: 5f7123808833 ("Pass pitch from drmmode_crtc_scanout_allocate to
                      drmmode_create_bo_pixmap")
(Ported from radeon commit 987a34adb319923ad36e2b47a26837248f187c3e)

Signed-off-by: Michel Dänzer <michel.daenzer at amd.com>
---
 src/drmmode_display.c | 27 +++++++++++++++++----------
 1 file changed, 17 insertions(+), 10 deletions(-)

diff --git a/src/drmmode_display.c b/src/drmmode_display.c
index 4c35657b..c7c9f179 100644
--- a/src/drmmode_display.c
+++ b/src/drmmode_display.c
@@ -1047,14 +1047,20 @@ static void drmmode_show_cursor(xf86CrtcPtr crtc)
 			 info->cursor_w, info->cursor_h);
 }
 
-static void *drmmode_crtc_shadow_allocate(xf86CrtcPtr crtc, int width,
-					  int height)
+/* Xorg expects a non-NULL return value from drmmode_crtc_shadow_allocate, and
+ * passes that back to drmmode_crtc_scanout_create; it doesn't use it for
+ * anything else.
+ */
+static void *
+drmmode_crtc_shadow_allocate(xf86CrtcPtr crtc, int width, int height)
 {
 	drmmode_crtc_private_ptr drmmode_crtc = crtc->driver_private;
-	int pitch;
 
-	return drmmode_crtc_scanout_allocate(crtc, &drmmode_crtc->rotate,
-					     width, height, &pitch);
+	if (!drmmode_crtc_scanout_create(crtc, &drmmode_crtc->rotate, width,
+					 height))
+		return NULL;
+
+	return (void*)~0UL;
 }
 
 static PixmapPtr
@@ -1062,11 +1068,12 @@ drmmode_crtc_shadow_create(xf86CrtcPtr crtc, void *data, int width, int height)
 {
 	drmmode_crtc_private_ptr drmmode_crtc = crtc->driver_private;
 
-	/* Xorg passes in the return value of drmmode_crtc_shadow_allocate
-	 * for data, but that's redundant for drmmode_crtc_scanout_create.
-	 */
-	return drmmode_crtc_scanout_create(crtc, &drmmode_crtc->rotate, width,
-					   height);
+	if (!data) {
+		drmmode_crtc_scanout_create(crtc, &drmmode_crtc->rotate, width,
+					    height);
+	}
+
+	return drmmode_crtc->rotate.pixmap;
 }
 
 static void
-- 
2.11.0