RE: [PATCH 1/1] tty: serial: samsung: add spin_lock for interrupt and console_write

Jaewon Kim
2022-04-06T12:36:58Z

Hello

On 22. 4. 6. 17:21, Greg Kroah-Hartman wrote:
> On Wed, Apr 06, 2022 at 05:22:16PM +0900, Jaewon Kim wrote:
> > The console_write and IRQ handler can run concurrently.
> > Problems may occurs console_write is continuously executed while the
> > IRQ handler is running.
> >
> > Signed-off-by: Jaewon Kim <jaewon02.kim@samsung.com>
> > ---
> > drivers/tty/serial/samsung_tty.c | 12 ++++++++++++
> > 1 file changed, 12 insertions(+)
> >
> > diff --git a/drivers/tty/serial/samsung_tty.c
> > b/drivers/tty/serial/samsung_tty.c
> > index e1585fbae909..9db479d728b5 100644
> > --- a/drivers/tty/serial/samsung_tty.c
> > +++ b/drivers/tty/serial/samsung_tty.c
> > @@ -2480,12 +2480,24 @@ s3c24xx_serial_console_write(struct console *co, const char *s,
> > unsigned int count)
> > {
> > unsigned int ucon = rd_regl(cons_uart, S3C2410_UCON);
> > + unsigned long flags;
> > + bool locked = 1;
>
> "1" is not a boolean :)

return value of spin_trylock() is 1 or 0.
It seems better to keep it as an int than to change it to bool.
I will return it to int.

Thanks
Jaewon Kim