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

Jaewon Kim
2022-04-06T13:48:15Z

On 22. 4. 6. 18:48, Jiri Slaby wrote:> On 06. 04. 22, 10:39, Jaewon Kim wrote:
> > 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.
>
> Hi, no, do not that. Simply use bool/true/false.
>

Okay, Thanks to review.
I will fix 1 to bool in next v3 patch.

> thanks,
> --
> js
> suse labs

Thanks
Jaewon Kim