From a9036ccbe2549cbfbbad660a4d0e70627ea35a5c Mon Sep 17 00:00:00 2001 From: Melissa Wen Date: Tue, 17 Dec 2024 13:26:55 -0300 Subject: [PATCH] drm/amd/display: fix divide error in plane scale calcs dm_get_plane_scale doesn't take into account plane scaled size equal to zero, leading to a kernel oops for division by zero. Fix by setting out-scale size as zero when the dst size is zero, similar to what is done by drm_calc_scale(). This issue started with the introduction of cursor ovelay mode that uses this function to assess cursor mode changes via dm_crtc_get_cursor_mode() before checking plane state. Fixes: 1b04dcca4fb1 ("drm/amd/display: Introduce overlay cursor mode") Link: https://gitlab.freedesktop.org/drm/amd/-/issues/3729 Reported-by: Fabio Scaccabarozzi <> Co-developed-by: Fabio Scaccabarozzi <> Signed-off-by: Fabio Scaccabarozzi <> Signed-off-by: Melissa Wen --- drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) 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 85f21db6ef24..2c795b867c1c 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c @@ -11124,8 +11124,8 @@ dm_get_plane_scale(struct drm_plane_state *plane_state, int plane_src_w, plane_src_h; dm_get_oriented_plane_size(plane_state, &plane_src_w, &plane_src_h); - *out_plane_scale_w = plane_state->crtc_w * 1000 / plane_src_w; - *out_plane_scale_h = plane_state->crtc_h * 1000 / plane_src_h; + *out_plane_scale_w = plane_src_w ? plane_state->crtc_w * 1000 / plane_src_w : 0; + *out_plane_scale_h = plane_src_h ? plane_state->crtc_h * 1000 / plane_src_h : 0; } /* -- 2.45.2