[PATCH] drm/ttm: fix ttm_bo_add_ttm(user) failure path

[Thomas Hellstrom]

Reviewed-by: Thomas Hellstrom <thellstrom at vmware.com>

On 08/22/2011 11:17 PM, Marcin Slusarz wrote:
> ttm_tt_destroy kfrees passed object, so we need to nullify
> a reference to it.
>
> Signed-off-by: Marcin Slusarz<marcin.slusarz at gmail.com>
> Cc: stable at kernel.org
> ---
>   drivers/gpu/drm/ttm/ttm_bo.c |    4 +++-
>   1 files changed, 3 insertions(+), 1 deletions(-)
>
> diff --git a/drivers/gpu/drm/ttm/ttm_bo.c b/drivers/gpu/drm/ttm/ttm_bo.c
> index 251df77..2e8f929 100644
> --- a/drivers/gpu/drm/ttm/ttm_bo.c
> +++ b/drivers/gpu/drm/ttm/ttm_bo.c
> @@ -353,8 +353,10 @@ static int ttm_bo_add_ttm(struct ttm_buffer_object *bo, bool zero_alloc)
>
>   		ret = ttm_tt_set_user(bo->ttm, current,
>   				      bo->buffer_start, bo->num_pages);
> -		if (unlikely(ret != 0))
> +		if (unlikely(ret != 0)) {
>   			ttm_tt_destroy(bo->ttm);
> +			bo->ttm = NULL;
> +		}
>   		break;
>   	default:
>   		printk(KERN_ERR TTM_PFX "Illegal buffer object type\n");
>