Re: [systemd-devel] [PATCH] tty: Set correct tty name in 'active'sysfs attribute

[Peter Hurley]

On 02/05/2014 07:53 AM, David Herrmann wrote:
> Hi
>
> On Wed, Feb 5, 2014 at 11:11 AM, Hannes Reinecke <hare@xxxxxxx> wrote:
> > The 'active' sysfs attribute should refer to the currently
> > active tty devices the console is running on, not the currently
> > active console.
> > The console structure doesn't refer to any device in sysfs,
> > only the tty the console is running on has.
> > So we need to print out the tty names in 'active', not
> > the console names.
> >
> > Cc: Lennart Poettering <lennart@xxxxxxxxxxxxxx>
> > Cc: Kay Sievers <kay@xxxxxxxx>
> > Signed-off-by: Werner Fink <werner@xxxxxxx>
> > Signed-off-by: Hannes Reinecke <hare@xxxxxxx>
> > ---
> >   drivers/tty/tty_io.c | 14 ++++++++++++--
> >   1 file changed, 12 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/tty/tty_io.c b/drivers/tty/tty_io.c
> > index c74a00a..17db8ca 100644
> > --- a/drivers/tty/tty_io.c
> > +++ b/drivers/tty/tty_io.c
> > @@ -3545,9 +3545,19 @@ static ssize_t show_cons_active(struct device *dev,
> >                  if (i >= ARRAY_SIZE(cs))
> >                          break;
> >          }
> > -       while (i--)
> > +       while (i--) {
> > +               const struct tty_driver *driver;
> > +               const char *name = cs[i]->name;
> > +               int index = cs[i]->index;
> > +
> > +               driver = cs[i]->device(cs[i], &index);
> > +               if (driver) {
> > +                       index += driver->name_base;
> > +                       name = driver->name;
> > +               }
> >                  count += sprintf(buf + count, "%s%d%c",
> > -                                cs[i]->name, cs[i]->index, i ? ' ':'\n');
> > +                                name, index, i ? ' ':'\n');
> > +       }
>
> Nice catch and indeed, systemd already relies on these names to be
> identical to their char-dev name. Fortunately, VTs and most serial
> devices register the console with the same name as the TTY, so we're
> fine.

What device did this trip over?

Also, this file is not private to systemd. Maybe these changes should
be forked into a different sysfs attribute, "active_devices"?

Regards,
Peter Hurley
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