Re: [PATCH vhost v13 04/12] virtio_ring: support add premapped buf

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Tue, Jun 4, 2024 at 6:07 PM Ilya Leoshkevich <iii@xxxxxxxxxxxxx> wrote:
>
> On Thu, 2023-08-10 at 20:30 +0800, Xuan Zhuo wrote:
> > If the vq is the premapped mode, use the sg_dma_address() directly.
> >
> > Signed-off-by: Xuan Zhuo <xuanzhuo@xxxxxxxxxxxxxxxxx>
> > ---
> >  drivers/virtio/virtio_ring.c | 19 +++++++++++++++++--
> >  1 file changed, 17 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/virtio/virtio_ring.c
> > b/drivers/virtio/virtio_ring.c
> > index 8e81b01e0735..f9f772e85a38 100644
> > --- a/drivers/virtio/virtio_ring.c
> > +++ b/drivers/virtio/virtio_ring.c
> > @@ -361,6 +361,11 @@ static struct device *vring_dma_dev(const struct
> > vring_virtqueue *vq)
> >  static int vring_map_one_sg(const struct vring_virtqueue *vq, struct
> > scatterlist *sg,
> >                           enum dma_data_direction direction,
> > dma_addr_t *addr)
> >  {
> > +     if (vq->premapped) {
> > +             *addr = sg_dma_address(sg);
> > +             return 0;
> > +     }
> > +
>
> I wonder if something needs to be done for KMSAN here, like it's done
> by the next block in this function? I'm looking into what seems to be a
> KMSAN false positive on s390x:
>
> BUG: KMSAN: uninit-value in receive_buf+0x45ca/0x6990
>  receive_buf+0x45ca/0x6990
>  virtnet_poll+0x17e0/0x3130
>  net_rx_action+0x832/0x26e0
>  handle_softirqs+0x330/0x10f0
>  [...]

I think there's a similar problem on x86 as well:
https://syzkaller.appspot.com/bug?extid=c5336dcd1b741349d27a

I was going to look closer this week.





[Index of Archives]     [Linux Samsung SoC]     [Linux Rockchip SoC]     [Linux Actions SoC]     [Linux for Synopsys ARC Processors]     [Linux NFS]     [Linux NILFS]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]


  Powered by Linux