drm/vmwgfx: Fix error printout on signals pending

commit e338c4c2 upstream.

The function vmw_master_check() might return -ERESTARTSYS if there is a
signal pending, indicating that the IOCTL should be rerun, potentially from
user-space. At that point we shouldn't print out an error message since that
is not an error condition. In short, avoid bloating the kernel log when a
process refuses to die on SIGTERM.
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Jakob Bornecrantz <jakob@vmware.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>

drivers/gpu/drm/vmwgfx/vmwgfx_drv.c

@@ -1070,8 +1070,12 @@ static long vmw_generic_ioctl(struct file *filp, unsigned int cmd,
 
 	vmaster = vmw_master_check(dev, file_priv, flags);
 	if (unlikely(IS_ERR(vmaster))) {
-		DRM_INFO("IOCTL ERROR %d\n", nr);
-		return PTR_ERR(vmaster);
+		ret = PTR_ERR(vmaster);
+
+		if (ret != -ERESTARTSYS)
+			DRM_INFO("IOCTL ERROR Command %d, Error %ld.\n",
+				 nr, ret);
+		return ret;
 	}
 
 	ret = ioctl_func(filp, cmd, arg);