Re: [PATCH] tty: Remove dead termiox code

From: Greg Kroah-Hartman
Date: Fri Dec 04 2020 - 04:10:05 EST


On Fri, Dec 04, 2020 at 09:51:07AM +0100, Jiri Slaby wrote:
> On 04. 12. 20, 9:36, Greg Kroah-Hartman wrote:
> > On Fri, Dec 04, 2020 at 09:20:39AM +0100, Jiri Slaby wrote:
> > > On 04. 12. 20, 9:17, Greg Kroah-Hartman wrote:
> > > > On Fri, Dec 04, 2020 at 08:22:41AM +0100, Jiri Slaby wrote:
> > > > > On 03. 12. 20, 3:03, Jann Horn wrote:
> > > > > > set_termiox() and the TCGETX handler bail out with -EINVAL immediately
> > > > > > if ->termiox is NULL, but there are no code paths that can set
> > > > > > ->termiox to a non-NULL pointer; and no such code paths seem to have
> > > > > > existed since the termiox mechanism was introduced back in
> > > > > > commit 1d65b4a088de ("tty: Add termiox") in v2.6.28.
> > > > > > Similarly, no driver actually implements .set_termiox; and it looks like
> > > > > > no driver ever has.
> > > > >
> > > > > Nice!
> > > > >
> > > > > > Delete this dead code; but leave the definition of struct termiox in the
> > > > > > UAPI headers intact.
>
> Note this ^^^^^. He is talking about _not_ touching the definition in the
> UAPI header. Does the rest below makes more sense now?

No, I'm still confused :)

We can't touch the UAPI definitions, but the fact that this api never
did anything still is ok as after this patch it continues to not do
anything.

I'm confused as to what you are proposing...

greg k-h