drm/vmwgfx: Fix src/dst_pitch confusion

The src/dst_pitch got mixed up during the rework of the function, make
sure the offset's refer to the correct one.

Spotted by clang:
Clang warns (or errors with CONFIG_WERROR):

  drivers/gpu/drm/vmwgfx/vmwgfx_stdu.c:509:29: error: variable 'dst_pitch' is uninitialized when used here [-Werror,-Wuninitialized]
          src_offset = ddirty->top * dst_pitch + ddirty->left * stdu->cpp;
                                     ^~~~~~~~~
  drivers/gpu/drm/vmwgfx/vmwgfx_stdu.c:492:26: note: initialize the variable 'dst_pitch' to silence this warning
          s32 src_pitch, dst_pitch;
                                  ^
                                   = 0
  1 error generated.

Signed-off-by: Zack Rusin <zackr@vmware.com>
Reported-by: Nathan Chancellor <nathan@kernel.org>
Reported-by: Dave Airlie <airlied@gmail.com>
Link: https://github.com/ClangBuiltLinux/linux/issues/1811
Fixes: 39985eea5a6d ("drm/vmwgfx: Abstract placement selection")
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Martin Krastev <krastevm@vmware.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230314211445.1363828-1-zack@kde.org

diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_stdu.c b/drivers/gpu/drm/vmwgfx/vmwgfx_stdu.c
index d79a6eccfaa440e3ed5cc3d4909f4322a6b0340c..ba0c0e12cfe9d02b838e071929a6ec1a62af3e62 100644 (file)
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_stdu.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_stdu.c
@@ -506,11 +506,11 @@ static void vmw_stdu_bo_cpu_commit(struct vmw_kms_dirty *dirty)
        /* Assume we are blitting from Guest (bo) to Host (display_srf) */
        src_pitch = stdu->display_srf->metadata.base_size.width * stdu->cpp;
        src_bo = &stdu->display_srf->res.guest_memory_bo->tbo;
-       src_offset = ddirty->top * dst_pitch + ddirty->left * stdu->cpp;
+       src_offset = ddirty->top * src_pitch + ddirty->left * stdu->cpp;
 
        dst_pitch = ddirty->pitch;
        dst_bo = &ddirty->buf->tbo;
-       dst_offset = ddirty->fb_top * src_pitch + ddirty->fb_left * stdu->cpp;
+       dst_offset = ddirty->fb_top * dst_pitch + ddirty->fb_left * stdu->cpp;
 
        (void) vmw_bo_cpu_blit(dst_bo, dst_offset, dst_pitch,
                               src_bo, src_offset, src_pitch,