Re: [PATCH v2 1/2] vhost_user: Offer VIRTIO_NET_F_GUEST_CSUM

[Stefano Brivio <sbrivio@redhat.com>]

On Tue, 26 May 2026 16:50:30 +0200
Laurent Vivier <lvivier@redhat.com> wrote:

> On 5/26/26 16:48, Stefano Brivio wrote:
> > On Tue, 26 May 2026 16:00:55 +0200
> > Laurent Vivier <lvivier@redhat.com> wrote:
> >   
> >> On 5/26/26 15:48, Stefano Brivio wrote:  
> >>> On Tue, 26 May 2026 14:58:16 +0200
> >>> Laurent Vivier <lvivier@redhat.com> wrote:
> >>>      
> >>>> Hi Stefano,
> >>>>
> >>>> could you apply this one too?  
> >>>
> >>> Wait, sorry, I skipped the whole series as I thought Anshu was
> >>> anyway working on a more general approach for 2/2.
> >>>
> >>> I should just apply 1/2 instead, right?  
> >>
> >> Yes, Anshu's series cover 2/2 but patch 1/2 fixes a problem between iPXE and passt
> >> vhost-user implementation.  
> > 
> > ...so I tried applying this one but it has quite a few conflicts with
> > your own series that I just applied.
> > 
> > Do you happen to have a rebased version at hand? Otherwise I'll go
> > ahead and solve the conflicts myself, they're not complicated.
> >   
> 
> No, I don't have something already rebased.

Applying now. Due to commit dec66c02b5e4 ("udp: Pass iov_tail to
udp_update_hdr4()/udp_update_hdr6()"), merged meanwhile, this part
in udp_vu_sock_to_tap():

			if (!vu_has_feature(vdev, VIRTIO_NET_F_GUEST_CSUM) ||
			    *c->pcap)
				udp_vu_csum(toside, &data, dlen);

became, in udp_vu_prepare():

	no_csum = vu_has_feature(c->vdev, VIRTIO_NET_F_GUEST_CSUM) && !*c->pcap;

[...]

		udp_update_hdr4(&iph, &uh, payload, toside, dlen, no_csum);

[...]

		udp_update_hdr6(&ip6h, &uh, payload, toside, dlen, no_csum);

-- 
Stefano