drm/vmwgfx: Fix 32-bit VMW_PORT_HB_[IN|OUT] macros
authorThomas Hellstrom <thellstrom@vmware.com>
Wed, 23 May 2018 14:11:24 +0000 (16:11 +0200)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 30 May 2018 05:51:48 +0000 (07:51 +0200)
commit760e4d7e89a53599a628cf7f176a4145b0e9dd29
tree25b84d3eab8aa573078cc1d4f3f1ed1f08b9d6eb
parenta0f8cbce7b573a2d646e9fbbc33d59007d99c8e6
drm/vmwgfx: Fix 32-bit VMW_PORT_HB_[IN|OUT] macros

commit 938ae7259c908ad031da35d551da297640bb640c upstream.

Depending on whether the kernel is compiled with frame-pointer or not,
the temporary memory location used for the bp parameter in these macros
is referenced relative to the stack pointer or the frame pointer.
Hence we can never reference that parameter when we've modified either
the stack pointer or the frame pointer, because then the compiler would
generate an incorrect stack reference.

Fix this by pushing the temporary memory parameter on a known location on
the stack before modifying the stack- and frame pointers.

Cc: <stable@vger.kernel.org>
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Brian Paul <brianp@vmware.com>
Reviewed-by: Sinclair Yeh <syeh@vmware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/gpu/drm/vmwgfx/vmwgfx_msg.h