Re: [PATCH -next] virtio: balloon: fix missing unlock on error in fill_balloon()

[Rafael Aquini <aquini@redhat.com>]

On Mon, Nov 12, 2012 at 09:50:40PM +0800, Wei Yongjun wrote:
> From: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
> 
> Add the missing unlock before return from function fill_balloon()
> in the error handling case.
> 
> Introduced by 9864a8(virtio_balloon: introduce migration primitives
> to balloon pages)
> 
> dpatch engine is used to auto generate this patch.
> (https://github.com/weiyj/dpatch)
> 
> Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
> ---
>  drivers/virtio/virtio_balloon.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c
> index f70151b..72e8dcb 100644
> --- a/drivers/virtio/virtio_balloon.c
> +++ b/drivers/virtio/virtio_balloon.c
> @@ -152,8 +152,10 @@ static void fill_balloon(struct virtio_balloon *vb, size_t num)
>  	}
>  
>  	/* Didn't get any?  Oh well. */
> -	if (vb->num_pfns == 0)
> +	if (vb->num_pfns == 0) {
> +		mutex_unlock(&vb->balloon_lock);
>  		return;
> +	}
>  
>  	tell_host(vb, vb->inflate_vq);
>  	mutex_unlock(&vb->balloon_lock);
>

I missed that one when rewriting v10 to v11. :(

Good catch, Wei! thanks!

Andrew, we need this pick for the virtio_balloon v12 patch, as well.

-- Rafael