Patch "drm/amdgpu: Use drm_mode_copy()" has been added to the 5.15-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

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

    drm/amdgpu: Use drm_mode_copy()

to the 5.15-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-amdgpu-use-drm_mode_copy.patch
and it can be found in the queue-5.15 subdirectory.

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



commit 633f58420f3ad4bae0b660725a8e1ca06e05de0d
Author: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx>
Date:   Fri Feb 18 12:03:45 2022 +0200

    drm/amdgpu: Use drm_mode_copy()
    
    [ Upstream commit 426c89aa203bcec9d9cf6eea36735eafa1b1f099 ]
    
    struct drm_display_mode embeds a list head, so overwriting
    the full struct with another one will corrupt the list
    (if the destination mode is on a list). Use drm_mode_copy()
    instead which explicitly preserves the list head of
    the destination mode.
    
    Even if we know the destination mode is not on any list
    using drm_mode_copy() seems decent as it sets a good
    example. Bad examples of not using it might eventually
    get copied into code where preserving the list head
    actually matters.
    
    Obviously one case not covered here is when the mode
    itself is embedded in a larger structure and the whole
    structure is copied. But if we are careful when copying
    into modes embedded in structures I think we can be a
    little more reassured that bogus list heads haven't been
    propagated in.
    
    @is_mode_copy@
    @@
    drm_mode_copy(...)
    {
    ...
    }
    
    @depends on !is_mode_copy@
    struct drm_display_mode *mode;
    expression E, S;
    @@
    (
    - *mode = E
    + drm_mode_copy(mode, &E)
    |
    - memcpy(mode, E, S)
    + drm_mode_copy(mode, E)
    )
    
    @depends on !is_mode_copy@
    struct drm_display_mode mode;
    expression E;
    @@
    (
    - mode = E
    + drm_mode_copy(&mode, &E)
    |
    - memcpy(&mode, E, S)
    + drm_mode_copy(&mode, E)
    )
    
    @@
    struct drm_display_mode *mode;
    @@
    - &*mode
    + mode
    
    Cc: Alex Deucher <alexander.deucher@xxxxxxx>
    Cc: Harry Wentland <harry.wentland@xxxxxxx>
    Cc: Leo Li <sunpeng.li@xxxxxxx>
    Cc: Rodrigo Siqueira <Rodrigo.Siqueira@xxxxxxx>
    Cc: amd-gfx@xxxxxxxxxxxxxxxxxxxxx
    Reviewed-by: Harry Wentland <harry.wentland@xxxxxxx>
    Signed-off-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx>
    Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
    Stable-dep-of: 79f3e38f60e5 ("drm/amd/display: Preserve original aspect ratio in create stream")
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_connectors.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_connectors.c
index c777aff164b76..654f99f4107ea 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_connectors.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_connectors.c
@@ -625,7 +625,7 @@ amdgpu_connector_fixup_lcd_native_mode(struct drm_encoder *encoder,
 		if (mode->type & DRM_MODE_TYPE_PREFERRED) {
 			if (mode->hdisplay != native_mode->hdisplay ||
 			    mode->vdisplay != native_mode->vdisplay)
-				memcpy(native_mode, mode, sizeof(*mode));
+				drm_mode_copy(native_mode, mode);
 		}
 	}
 
@@ -634,7 +634,7 @@ amdgpu_connector_fixup_lcd_native_mode(struct drm_encoder *encoder,
 		list_for_each_entry_safe(mode, t, &connector->probed_modes, head) {
 			if (mode->hdisplay == native_mode->hdisplay &&
 			    mode->vdisplay == native_mode->vdisplay) {
-				*native_mode = *mode;
+				drm_mode_copy(native_mode, mode);
 				drm_mode_set_crtcinfo(native_mode, CRTC_INTERLACE_HALVE_V);
 				DRM_DEBUG_KMS("Determined LVDS native mode details from EDID\n");
 				break;
diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
index 7385efe699f88..9356decd14513 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -6219,7 +6219,7 @@ get_highest_refresh_rate_mode(struct amdgpu_dm_connector *aconnector,
 		}
 	}
 
-	aconnector->freesync_vid_base = *m_pref;
+	drm_mode_copy(&aconnector->freesync_vid_base, m_pref);
 	return m_pref;
 }
 
@@ -6333,8 +6333,8 @@ create_stream_for_sink(struct amdgpu_dm_connector *aconnector,
 				 is_freesync_video_mode(&mode, aconnector);
 		if (recalculate_timing) {
 			freesync_mode = get_highest_refresh_rate_mode(aconnector, false);
-			saved_mode = mode;
-			mode = *freesync_mode;
+			drm_mode_copy(&saved_mode, &mode);
+			drm_mode_copy(&mode, freesync_mode);
 		} else {
 			decide_crtc_timing_for_drm_display_mode(
 				&mode, preferred_mode, scale);