From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jason Wang Subject: Re: [PATCH] vhost: fix length for cross region descriptor Date: Tue, 27 Nov 2012 13:47:50 +0800 Message-ID: <50B45406.40603@redhat.com> References: <20121126155727.GA21716@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, David Miller , linux-kernel@vger.kernel.org To: "Michael S. Tsirkin" Return-path: In-Reply-To: <20121126155727.GA21716@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On 11/26/2012 11:57 PM, Michael S. Tsirkin wrote: > If a single descriptor crosses a region, the > second chunk length should be decremented > by size translated so far, instead it includes > the full descriptor length. > > Signed-off-by: Michael S. Tsirkin > --- > drivers/vhost/vhost.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c > index ef8f598..5a3d0f1 100644 > --- a/drivers/vhost/vhost.c > +++ b/drivers/vhost/vhost.c > @@ -1049,7 +1049,7 @@ static int translate_desc(struct vhost_dev *dev, u64 addr, u32 len, > } > _iov = iov + ret; > size = reg->memory_size - addr + reg->guest_phys_addr; > - _iov->iov_len = min((u64)len, size); > + _iov->iov_len = min((u64)len - s, size); > _iov->iov_base = (void __user *)(unsigned long) > (reg->userspace_addr + addr - reg->guest_phys_addr); > s += size; Acked-by: Jason Wang