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

On Thu, Sep 18, 2025 at 12:18:47PM -0400, Michael S. Tsirkin wrote:
> Filip Hejsek pointed out the following:
> 
> The problem is that for a long time, the
> Linux kernel used a different field order from what was specified in the
> virtio spec. The kernel implementation was apparently merged around 2010,
> while the virtio spec came in 2014, so when a previous version of this
> patch series was being discussed here on the qemu-devel mailing list in
> 2020, it was decided that QEMU should match the Linux implementation,
> and ideally, the virtio spec should be changed.
> 
> There are about 15 years' worth
> of kernel versions with the swapped field order, including the kernel
> currently shipped in Debian stable. The effects of the swapped dimensions
> can sometimes be quite annoying - e.g. if you have a terminal with
> 24 rows, this will be interpreted as 24 columns, and your shell may limit
> line editing to this small space, most of which will be taken by your
> prompt.
> 
> 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.
> 
> Change the spec to match.
> 
> Reported-by: Filip Hejsek <[email protected]>
> Cc: "Maximilian Immanuel Brandtner" <[email protected]>
> Signed-off-by: Michael S. Tsirkin <[email protected]>
> ---
>  device-types/console/description.tex | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 

Reviewed-by: Matias Ezequiel Vara Larsen <[email protected]>