Re: [GIT PULL] TTY/Serial driver updates for 6.3-rc1

From: Theodore Ts'o
Date: Sun Feb 26 2023 - 15:00:22 EST


On Sat, Feb 25, 2023 at 06:14:11PM -0800, Linus Torvalds wrote:
> On Sat, Feb 25, 2023 at 3:40 PM Theodore Ts'o <tytso@xxxxxxx> wrote:
> >
> > For what it's worth, in the VM world (e.g., qemu, AWS, GCP, Azure,
> > Linode, etc.) serial consoles are quite common way of debugging VM's,
> > and as an emergency login path when the networking has been screwed up
> > for some reason....
>
> Everybody seems to be missing the point.
>
> We don't make new drivers "default y" (or, in this case, "default SERIAL_8250".
>
> It does not matter ONE WHIT if you have a serial device in your
> machine. If your old driver was enabled and worked for you and you
> used it daily, that is ENTIRELY IMMATERIAL to a new driver, even if
> that new driver then happens to use some of the same infrastructure as
> the old one did.

Oh, agreed, I wasn't responding to that part of your message. New
serial drivers should never be enabled by default.

I was responding to your musing about whether it still made sense to
enable the COM1/2/3/4 serial ports by default on x86. It's true that
on desktops COM1/2/3/4 serial ports are rarely used, and some other
boards might not even have them any more. But for x86 VM's, they are
used quite a lot.

Cheers,

- Ted