drm/vmwgfx: Fix a width / pitch mismatch on framebuffer updates

When the framebuffer is a vmwgfx dma buffer and a proxy surface is
created, the vmw_kms_update_proxy() function requires that the proxy
surface width and the framebuffer pitch are compatible, otherwise
display corruption occurs as seen in gnome-shell/native with software
3D. Since the framebuffer pitch is determined by user-space, allocate
a proxy surface the width of which is based on the framebuffer pitch
rather than on the framebuffer width.

Cc: <stable@vger.kernel.org>
Reported-by: Raphael Hertzog <buxy@kali.org>
Tested-by:  Mati Aharoni <muts@kali.org>
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Brian Paul <brianp@vmware.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c b/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c
index 274c90da44a74646712b743f269babed93d8eedf..b221a8c4028228d31707df756c14507084603f23 100644 (file)
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c
@@ -763,21 +763,25 @@ static int vmw_create_dmabuf_proxy(struct drm_device *dev,
        uint32_t format;
        struct drm_vmw_size content_base_size;
        struct vmw_resource *res;
+       unsigned int bytes_pp;
        int ret;
 
        switch (mode_cmd->depth) {
        case 32:
        case 24:
                format = SVGA3D_X8R8G8B8;
+               bytes_pp = 4;
                break;
 
        case 16:
        case 15:
                format = SVGA3D_R5G6B5;
+               bytes_pp = 2;
                break;
 
        case 8:
                format = SVGA3D_P8;
+               bytes_pp = 1;
                break;
 
        default:
@@ -785,7 +789,7 @@ static int vmw_create_dmabuf_proxy(struct drm_device *dev,
                return -EINVAL;
        }
 
-       content_base_size.width  = mode_cmd->width;
+       content_base_size.width  = mode_cmd->pitch / bytes_pp;
        content_base_size.height = mode_cmd->height;
        content_base_size.depth  = 1;