[Acked] [SRU][Wily] drm/vmwgfx: Fix an fb unlocking bug

[Andy Whitcroft]

On Thu, Feb 25, 2016 at 09:57:31AM -0800, Kamal Mostafa wrote:
> From: Thomas Hellstrom <thellstrom at vmware.com>
> 
> BugLink: http://bugs.launchpad.net/bugs/1548587
> 
> commit 12617971c443c50750a12a77ea0e08319d161975 upstream.
> 
> A regression introduced when the master ttm lock was split into two.
> 
> Reported-and-tested-by: Brian Paul <brianp at vmware.com>
> Signed-off-by: Thomas Hellstrom <thellstrom at vmware.com>
> Reviewed-by: Brian Paul <brianp at vmware.com>
> Signed-off-by: Kamal Mostafa <kamal at canonical.com>
> ---
>  drivers/gpu/drm/vmwgfx/vmwgfx_fb.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_fb.c b/drivers/gpu/drm/vmwgfx/vmwgfx_fb.c
> index 0a474f3..e2d40eb 100644
> --- a/drivers/gpu/drm/vmwgfx/vmwgfx_fb.c
> +++ b/drivers/gpu/drm/vmwgfx/vmwgfx_fb.c
> @@ -402,12 +402,12 @@ static int vmw_fb_create_bo(struct vmw_private *vmw_priv,
>  
>  	*out = vmw_bo;
>  
> -	ttm_write_unlock(&vmw_priv->fbdev_master.lock);
> +	ttm_write_unlock(&vmw_priv->reservation_sem);
>  
>  	return 0;
>  
>  err_unlock:
> -	ttm_write_unlock(&vmw_priv->fbdev_master.lock);
> +	ttm_write_unlock(&vmw_priv->reservation_sem);
>  	return ret;
>  }
>  

Clean cherry-pick, tested to fix the underlying issue.

Acked-by: Andy Whitcroft <apw at canonical.com>

-apw