Re: [PATCH] virtio_console: fix order of fields cols and rows

["Michael S. Tsirkin" <mst@redhat.com>]

On Mon, Oct 13, 2025 at 02:00:22PM +0900, Dominique Martinet wrote:
> Michael S. Tsirkin wrote on Thu, Sep 18, 2025 at 12:18:47PM -0400:
> > While commit 5326ab737a47278dbd16ed3ee7380b26c7056ddd in Linux made it
> > match the spec, no one seems to have implemented it yet host side. It
> > seems better to just drop the change (it was only in 2 releases so far),
> > going back to the status quo.
> 
> FWIW, there are other users of the spec e.g. bhyve, which implemented it
> "right" (cols, rows as per the spec -- since 2016):
> https://github.com/freebsd/freebsd-src/blob/main/usr.sbin/bhyve/pci_virtio_console.c#L148
> 
> or crossvm (also cols,rows)
> https://github.com/google/crosvm/blob/main/devices/src/virtio/device_constants.rs#L293
> 


Indeed, thanks for bringing this to our attention.


> I didn't look to see if there are others (probably some of the other
> rust hypervisor crowd?); I'm not involved in any of them but given there
> are other implementations I'd personally think it makes more sense to
> continue the work of "righting" linux (that is backport the order
> fix)...?

Yes, this is what we normally do. The reason I wanted to do it
differently here is because I did not realize we have implementations.

> I don't have any beef either way as long as the qemu patches aren't
> forgotten (thank you again Filip!); hopefully this can help reach any
> kind of decision.
> 
> If this was discussed somewhere else I'd appreciate being pointed to
> it :) I "only" found the recent qemu patches, an attempt to revert the
> fix in linux that was held back, and the stble backport thread where the
> issue was raised but not really discussed either way.
> 
> Thanks,
> -- 
> Dominique Martinet | Asmadeus


OK I guess ... let's get the ball rolling with backporting the Linux
fix?

-- 
MST