linux-kernel - Re: [PATCH V6 15/19] virtio_ring: factor out core logic of buffer detaching

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <CACGkMEsFrSH=LC4AFKcxCaxXArdtJtyaCQBko_vieT1VAscRHQ@mail.gmail.com>
Date: Mon, 22 Sep 2025 08:46:54 +0800
From: Jason Wang <jasowang@...hat.com>
To: "Michael S. Tsirkin" <mst@...hat.com>
Cc: xuanzhuo@...ux.alibaba.com, eperezma@...hat.com, 
	virtualization@...ts.linux.dev, linux-kernel@...r.kernel.org
Subject: Re: [PATCH V6 15/19] virtio_ring: factor out core logic of buffer detaching

On Mon, Sep 22, 2025 at 1:42 AM Michael S. Tsirkin <mst@...hat.com> wrote:
>
> On Fri, Sep 19, 2025 at 03:31:50PM +0800, Jason Wang wrote:
> > Factor out core logic of buffer detaching and leave the id population
> > to the caller so in order can just call the core logic.
> >
> > Acked-by: Eugenio Pérez <eperezma@...hat.com>
> > Reviewed-by: Xuan Zhuo <xuanzhuo@...ux.alibaba.com>
> > Signed-off-by: Jason Wang <jasowang@...hat.com>
> > ---
> >  drivers/virtio/virtio_ring.c | 17 +++++++++++++----
> >  1 file changed, 13 insertions(+), 4 deletions(-)
> >
> > diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
> > index 0949675a3d12..a83d08070e8a 100644
> > --- a/drivers/virtio/virtio_ring.c
> > +++ b/drivers/virtio/virtio_ring.c
> > @@ -1662,8 +1662,8 @@ static bool virtqueue_kick_prepare_packed(struct vring_virtqueue *vq)
> >       return needs_kick;
> >  }
> >
> > -static void detach_buf_packed(struct vring_virtqueue *vq,
> > -                           unsigned int id, void **ctx)
> > +static void detach_buf_packed_in_order(struct vring_virtqueue *vq,
> > +                                    unsigned int id, void **ctx)
> >  {
> >       struct vring_desc_state_packed *state = NULL;
> >       struct vring_packed_desc *desc;
> > @@ -1674,8 +1674,6 @@ static void detach_buf_packed(struct vring_virtqueue *vq,
> >       /* Clear data ptr. */
> >       state->data = NULL;
> >
> > -     vq->packed.desc_extra[state->last].next = vq->free_head;
> > -     vq->free_head = id;
> >       vq->vq.num_free += state->num;
> >
> >       if (unlikely(vq->use_map_api)) {
> > @@ -1712,6 +1710,17 @@ static void detach_buf_packed(struct vring_virtqueue *vq,
> >       }
> >  }
> >
> > +static void detach_buf_packed(struct vring_virtqueue *vq,
> > +                           unsigned int id, void **ctx)
> > +{
> > +     struct vring_desc_state_packed *state = &vq->packed.desc_state[id];
> > +
> > +     vq->packed.desc_extra[state->last].next = vq->free_head;
> > +     vq->free_head = id;
> > +
> > +     return detach_buf_packed_in_order(vq, id, ctx);
> > +}
> > +
>
> Wait what? return in a void function?
> How does this compile?

It looks like it passes the compiling since detach_buf_packed_in_order
returns void as well :(

> I'm guessing it's tweaked by a follow
> up patch?

Nope. Let me drop the return here.

Thanks

>
>
> >  static inline bool is_used_desc_packed(const struct vring_virtqueue *vq,
> >                                      u16 idx, bool used_wrap_counter)
> >  {
> > --
> > 2.31.1
>