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.

The assignments were switched around in such a way that dst_pitch was
used before it was assigned. Swap the pitch assignments to fix the issue
and make it clear which section they are used in.

Fixes: 39985eea5a6d ("drm/vmwgfx: Abstract placement selection")
Link: https://github.com/ClangBuiltLinux/linux/issues/1811
Signed-off-by: Nathan Chancellor <nat...@kernel.org>
---
I am not sure if this is the right fix, as it was not entirely clear to
me that src_pitch and dst_pitch were being used in the right assignments
but this is the obvious fix otherwise. Consider this a bug report if
not :)
---
 drivers/gpu/drm/vmwgfx/vmwgfx_stdu.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_stdu.c 
b/drivers/gpu/drm/vmwgfx/vmwgfx_stdu.c
index d79a6eccfaa4..030e977c68e2 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_stdu.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_stdu.c
@@ -504,11 +504,11 @@ static void vmw_stdu_bo_cpu_commit(struct vmw_kms_dirty 
*dirty)
                return;
 
        /* Assume we are blitting from Guest (bo) to Host (display_srf) */
-       src_pitch = stdu->display_srf->metadata.base_size.width * stdu->cpp;
+       dst_pitch = ddirty->pitch;
        src_bo = &stdu->display_srf->res.guest_memory_bo->tbo;
        src_offset = ddirty->top * dst_pitch + ddirty->left * stdu->cpp;
 
-       dst_pitch = ddirty->pitch;
+       src_pitch = stdu->display_srf->metadata.base_size.width * stdu->cpp;
        dst_bo = &ddirty->buf->tbo;
        dst_offset = ddirty->fb_top * src_pitch + ddirty->fb_left * stdu->cpp;
 

---
base-commit: c87e859cdeb5d106cb861326e3135c606d61f88d
change-id: 20230314-vmware-wuninitialized-28666fb5a62b

Best regards,
-- 
Nathan Chancellor <nat...@kernel.org>

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