From ab709795e38637320fea9fdc8e06b64f670b58ee Mon Sep 17 00:00:00 2001 From: Zack Rusin Date: Fri, 18 Mar 2022 13:43:29 -0400 Subject: [PATCH] drm/vmwgfx: Fix mob cursor allocation race Writes to SVGA_REG_CURSOR_MOBID did not wait for the buffers to be fully populated. This sometimes results in the device not being aware of the buffer when the cursor mob register was written. Properly wait for the buffer to be fully populated before setting it as a cursor mob. Signed-off-by: Zack Rusin Fixes: 485d98d472d5 ("drm/vmwgfx: Add support for CursorMob and CursorBypass 4") Reviewed-by: Martin Krastev Link: https://patchwork.freedesktop.org/patch/msgid/20220318174332.440068-3-zack@kde.org --- drivers/gpu/drm/vmwgfx/vmwgfx_kms.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c b/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c index af252210ef847..7a23f252d2121 100644 --- a/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c +++ b/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c @@ -602,6 +602,14 @@ vmw_du_cursor_plane_prepare_fb(struct drm_plane *plane, ret = ttm_bo_kmap(cm_bo, 0, PFN_UP(size), &vps->cm_map); + /* + * We just want to try to get mob bind to finish + * so that the first write to SVGA_REG_CURSOR_MOBID + * is done with a buffer that the device has already + * seen + */ + (void) ttm_bo_wait(cm_bo, false, false); + ttm_bo_unreserve(cm_bo); if (unlikely(ret != 0)) { -- 2.30.2