Re: [PATCH v2 1/5] console: Don't perform test for CON_BRL flag twice

From: Andy Shevchenko
Date: Mon Jan 27 2020 - 04:44:06 EST


On Mon, Jan 27, 2020 at 11:41:14AM +0900, Sergey Senozhatsky wrote:
> On (20/01/24 17:57), Andy Shevchenko wrote:
> [..]
> > +++ b/drivers/accessibility/braille/braille_console.c
> > @@ -369,10 +369,10 @@ int braille_register_console(struct console *console, int index,
> >
> > int braille_unregister_console(struct console *console)
> > {
> > - if (braille_co != console)
> > - return -EINVAL;
> > if (!(console->flags & CON_BRL))
> > return 0;
> > + if (braille_co != console)
> > + return -EINVAL;
> > unregister_keyboard_notifier(&keyboard_notifier_block);
> > unregister_vt_notifier(&vt_notifier_block);
> > braille_co = NULL;
> > diff --git a/kernel/printk/braille.c b/kernel/printk/braille.c
> > index 17a9591e54ff..2ec42173890f 100644
> > --- a/kernel/printk/braille.c
> > +++ b/kernel/printk/braille.c
> > @@ -51,8 +51,5 @@ _braille_register_console(struct console *console, struct console_cmdline *c)
> > int
> > _braille_unregister_console(struct console *console)
> > {
> > - if (console->flags & CON_BRL)
> > - return braille_unregister_console(console);
> > -
> > - return 0;
> > + return braille_unregister_console(console);
> > }
>
> Hmm, I don't know. This moves sort of important code from common upper
> layer down to particular driver implementation. Should there be another
> driver/super-braille.c it must test CON_BRL flag as well.
> Because printk invokes _braille_unregister_console() unconditionally,
> and _braille_unregister_console() unconditionally calls into the driver.
>
> I guess we can remove CON_BRL from braille_unregister_console() instead,
> because printk tests it.

Let me do that way, thanks!

--
With Best Regards,
Andy Shevchenko