Re: [PATCH v3] net/9p: add vsock transport

[Dominique Martinet <asmadeus@codewreck.org>]

skvarlamatus@gmail.com wrote on Mon, Sep 14, 2026 at 07:51:56PM +0200:
>> Do you have/use an hypervisor that cannot do virito 9p (or virtfs) but
>> has vsock or something like that?
> 
> virtio-9p is only supported by Qemu/KVM. Vsock transport works on any hypervisor
> with vsock support and allows using userspace 9P servers.
> The motivation behind this patch is primarily driven by podman machine's
> use-case, which is file sharing on Windows [1] [2].
> The hypervisor there is Hyper-V/WSL, which supports vsock for host-guest
> data transfers [3], but not virtio-9p or virtfs. Having vsock transport in the
> driver would simplify the codebase and make the use-case more flexible.

Okay, thank you for the explanation -- I'll add a blurb to the commit
message with your links for reference.

> > On a similar topic, do you have an actual server that works with vsock?
> 
> Podman implements its own 9P server in Go using the p9 library [4] with
> vsock support via virtsock [5], but it runs as part of podman machine.
> For standalone 9p servers, I only know of diod and example implementations
> of various 9p server libraries (i.e. [6]), but none of them support vsock.

Right, diod has an open issue[1] for vsock but since there were no
obvious client available either it was never done.
I don't think it's difficult to do (probably more work to add the option
parsing than the actual vsock support), but for now I was able to verify
this works with diod + socat as described in the issue, so this can come
later if/when there is interest for other hypervisors.

[1] https://github.com/chaos/diod/issues/148
-- 
Dominique Martinet | Asmadeus