From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Michael S. Tsirkin" <mst@redhat.com>
Subject: Re: [PATCH 1/4] tcm_vhost: Add missed lock in
	vhost_scsi_clear_endpoint()
Date: Tue, 12 Mar 2013 13:13:44 +0200
Message-ID: <20130312111344.GC6788@redhat.com>
References: <1363056171-5854-1-git-send-email-asias@redhat.com>
	<1363056171-5854-2-git-send-email-asias@redhat.com>
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To: Asias He <asias@redhat.com>
Cc: kvm@vger.kernel.org, virtualization@lists.linux-foundation.org, target-devel@vger.kernel.org, Stefan Hajnoczi <stefanha@redhat.com>, Paolo Bonzini <pbonzini@redhat.com>
List-Id: virtualization@lists.linuxfoundation.org

On Tue, Mar 12, 2013 at 10:42:48AM +0800, Asias He wrote:
> tv_tpg->tv_tpg_vhost_count should be protected by tv_tpg->tv_tpg_mutex.
> 
> Signed-off-by: Asias He <asias@redhat.com>
> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
> ---
>  drivers/vhost/tcm_vhost.c | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/drivers/vhost/tcm_vhost.c b/drivers/vhost/tcm_vhost.c
> index 9951297..b3e50d7 100644
> --- a/drivers/vhost/tcm_vhost.c
> +++ b/drivers/vhost/tcm_vhost.c
> @@ -860,9 +860,11 @@ static int vhost_scsi_clear_endpoint(
>  		if (!tv_tpg)
>  			continue;
>  
> +		mutex_lock(&tv_tpg->tv_tpg_mutex);
>  		tv_tport = tv_tpg->tport;
>  		if (!tv_tport) {
>  			ret = -ENODEV;
> +			mutex_unlock(&tv_tpg->tv_tpg_mutex);
>  			goto err;
>  		}
>  
> @@ -872,11 +874,13 @@ static int vhost_scsi_clear_endpoint(
>  				tv_tport->tport_name, tv_tpg->tport_tpgt,
>  				t->vhost_wwpn, t->vhost_tpgt);
>  			ret = -EINVAL;
> +			mutex_unlock(&tv_tpg->tv_tpg_mutex);
>  			goto err;
>  		}
>  		tv_tpg->tv_tpg_vhost_count--;
>  		vs->vs_tpg[target] = NULL;
>  		vs->vs_endpoint = false;
> +		mutex_unlock(&tv_tpg->tv_tpg_mutex);
>  	}
>  	mutex_unlock(&vs->dev.mutex);
>  	return 0;

Does the error handling have to be so messy?
How about another label which does unlock and goto there?

> -- 
> 1.8.1.4