From mboxrd@z Thu Jan  1 00:00:00 1970
From: Asias He <asias@redhat.com>
Subject: Re: [patch] virtio-blk: fix NULL checking in virtblk_alloc_req()
Date: Thu, 06 Sep 2012 11:02:48 +0800
Message-ID: <50481258.3080203@redhat.com>
References: <20120905123252.GE6128@elgon.mountain>
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To: Dan Carpenter <dan.carpenter@oracle.com>
Cc: kernel-janitors@vger.kernel.org, virtualization@lists.linux-foundation.org, "Michael S. Tsirkin" <mst@redhat.com>
List-Id: virtualization@lists.linuxfoundation.org

Hello Dan,

On 09/05/2012 08:32 PM, Dan Carpenter wrote:
> Smatch complains about the inconsistent NULL checking here.  Fix it to
> return NULL on failure.
> 
> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>

Thanks for catching this.

> ---
> This is only needed in linux-next.
> 
> diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c
> index 2edfb5c..457db0c 100644
> --- a/drivers/block/virtio_blk.c
> +++ b/drivers/block/virtio_blk.c
> @@ -90,10 +90,11 @@ static inline struct virtblk_req *virtblk_alloc_req(struct virtio_blk *vblk,
>  	struct virtblk_req *vbr;
>  
>  	vbr = mempool_alloc(vblk->pool, gfp_mask);
> -	if (vbr && use_bio)
> -		sg_init_table(vbr->sg, vblk->sg_elems);
> +	if (!vbr)
> +		return NULL;
>  
> -	vbr->vblk = vblk;

The assignment of vbr->vblk is needed.

> +	if (use_bio)
> +		sg_init_table(vbr->sg, vblk->sg_elems);
>  
>  	return vbr;
>  }






-- 
Asias