Re: [GIT PULL] virtio: features

From: Jason Wang
Date: Fri Dec 01 2023 - 00:15:59 EST


On Thu, Nov 30, 2023 at 5:44 PM Michael S. Tsirkin <mst@xxxxxxxxxx> wrote:
>
> On Wed, Nov 29, 2023 at 06:20:31PM +0800, Jason Wang wrote:
> > On Wed, Nov 29, 2023 at 6:12 PM Ning, Hongyu
> > <hongyu.ning@xxxxxxxxxxxxxxx> wrote:
> > >
> > >
> > > On 2023/11/29 17:16, Jason Wang wrote:
> > > > On Wed, Nov 29, 2023 at 5:05 PM Ning, Hongyu
> > > > <hongyu.ning@xxxxxxxxxxxxxxx> wrote:
> > > >>
> > > >>
> > > >>
> > > >> On 2023/9/4 6:13, Michael S. Tsirkin wrote:
> > > >>> The following changes since commit 2dde18cd1d8fac735875f2e4987f11817cc0bc2c:
> > > >>>
> > > >>> Linux 6.5 (2023-08-27 14:49:51 -0700)
> > > >>>
> > > >>> are available in the Git repository at:
> > > >>>
> > > >>> https://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost.git tags/for_linus
> > > >>>
> > > >>> for you to fetch changes up to 1acfe2c1225899eab5ab724c91b7e1eb2881b9ab:
> > > >>>
> > > >>> virtio_ring: fix avail_wrap_counter in virtqueue_add_packed (2023-09-03 18:10:24 -0400)
> > > >>>
> > > >>> ----------------------------------------------------------------
> > > >>> virtio: features
> > > >>>
> > > >>> a small pull request this time around, mostly because the
> > > >>> vduse network got postponed to next relase so we can be sure
> > > >>> we got the security store right.
> > > >>>
> > > >>> Signed-off-by: Michael S. Tsirkin <mst@xxxxxxxxxx>
> > > >>>
> > > >>> ----------------------------------------------------------------
> > > >>> Eugenio Pérez (4):
> > > >>> vdpa: add VHOST_BACKEND_F_ENABLE_AFTER_DRIVER_OK flag
> > > >>> vdpa: accept VHOST_BACKEND_F_ENABLE_AFTER_DRIVER_OK backend feature
> > > >>> vdpa: add get_backend_features vdpa operation
> > > >>> vdpa_sim: offer VHOST_BACKEND_F_ENABLE_AFTER_DRIVER_OK
> > > >>>
> > > >>> Jason Wang (1):
> > > >>> virtio_vdpa: build affinity masks conditionally
> > > >>>
> > > >>> Xuan Zhuo (12):
> > > >>> virtio_ring: check use_dma_api before unmap desc for indirect
> > > >>> virtio_ring: put mapping error check in vring_map_one_sg
> > > >>> virtio_ring: introduce virtqueue_set_dma_premapped()
> > > >>> virtio_ring: support add premapped buf
> > > >>> virtio_ring: introduce virtqueue_dma_dev()
> > > >>> virtio_ring: skip unmap for premapped
> > > >>> virtio_ring: correct the expression of the description of virtqueue_resize()
> > > >>> virtio_ring: separate the logic of reset/enable from virtqueue_resize
> > > >>> virtio_ring: introduce virtqueue_reset()
> > > >>> virtio_ring: introduce dma map api for virtqueue
> > > >>> virtio_ring: introduce dma sync api for virtqueue
> > > >>> virtio_net: merge dma operations when filling mergeable buffers
> > > >>
> > > >> Hi,
> > > >> above patch (upstream commit 295525e29a5b) seems causing a virtnet
> > > >> related Call Trace after WARNING from kernel/dma/debug.c.
> > > >>
> > > >> details (log and test setup) tracked in
> > > >> https://bugzilla.kernel.org/show_bug.cgi?id=218204
> > > >>
> > > >> it's recently noticed in a TDX guest testing since v6.6.0 release cycle
> > > >> and can still be reproduced in latest v6.7.0-rc3.
> > > >>
> > > >> as local bisects results show, above WARNING and Call Trace is linked
> > > >> with this patch, do you mind to take a look?
> > > >
> > > > Looks like virtqueue_dma_sync_single_range_for_cpu() use
> > > > DMA_BIDIRECTIONAL unconditionally.
> > > >
> > > > We should use dir here.
> > > >
> > > > Mind to try?
> > > >
> > > > Thanks
> > > >
> > >
> > > sure, but what I see in the code
> > > virtqueue_dma_sync_single_range_for_cpu() is using DMA_FROM_DEVICE,
> > > probably I misunderstood your point?
> > >
> > > Please let me know any patch/setting to try here.
> >
> > Something like attached. (Not even compiling test).
> >
> > Thanks
>
> Forwarding it inline for the record - I am not sure all the
> 0 day machinery handles attachments. Jason given it's reported to work
> can you please repost properly with a full commit log etc?
> I think we also need to fix virtqueue_dma_sync_single_range_for_device -
> please include that too.

Yes, want to sent something like this yesterday but it was interrupted
by other tasks.

I see Xuan has posted a patch, I will ack on that.

Thanks

>
>
> From: Jason Wang <jasowang@xxxxxxxxxx>
> Date: Wed, 29 Nov 2023 17:14:15 +0800
> Subject: [PATCH] virtio_ring: fix DMA dir during sync
> Content-type: text/plain
>
> Signed-off-by: Jason Wang <jasowang@xxxxxxxxxx>
> Signed-off-by: Michael S. Tsirkin <mst@xxxxxxxxxx>
>
> ---
> drivers/virtio/virtio_ring.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
> index 81ecb29c88f1..91d869814373 100644
> --- a/drivers/virtio/virtio_ring.c
> +++ b/drivers/virtio/virtio_ring.c
> @@ -3220,7 +3220,7 @@ void virtqueue_dma_sync_single_range_for_cpu(struct virtqueue *_vq,
> return;
>
> dma_sync_single_range_for_cpu(dev, addr, offset, size,
> - DMA_BIDIRECTIONAL);
> + dir);
> }
> EXPORT_SYMBOL_GPL(virtqueue_dma_sync_single_range_for_cpu);
>
> --
> 2.42.0
>