Re: [PATCH v2] console: console: Complete exception handling in newport_probe()

From: Bartlomiej Zolnierkiewicz
Date: Thu Apr 23 2020 - 10:55:40 EST



Hi,

I believe that the patch summary line should be:

"[PATCH v2] console: newport_con: ..."

On 4/23/20 4:26 PM, Dejin Zheng wrote:
> A call of the function ÂÂdo_take_over_consoleÂÂ can fail here.
> The corresponding system resources were not released then.
> Thus add a call of the function ÂÂiounmapÂÂ together with the check
> of a failure predicate.
>
> Fixes: e84de0c6190503 ("MIPS: GIO bus support for SGI IP22/28")

I cannot see how this patch fixes commit e84de0c6190503
(AFAICS npregs has also been leaked on error before)?

> CC: Andy Shevchenko <andy.shevchenko@xxxxxxxxx>
> Signed-off-by: Dejin Zheng <zhengdejin5@xxxxxxxxx>
> ---
> v1 -> v2:
> - modify the commit comments by Markus'suggestion.
>
> drivers/video/console/newport_con.c | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/drivers/video/console/newport_con.c b/drivers/video/console/newport_con.c
> index 00dddf6e08b0..6bfc8e3ffd4a 100644
> --- a/drivers/video/console/newport_con.c
> +++ b/drivers/video/console/newport_con.c
> @@ -720,6 +720,9 @@ static int newport_probe(struct gio_device *dev,
> console_lock();
> err = do_take_over_console(&newport_con, 0, MAX_NR_CONSOLES - 1, 1);
> console_unlock();
> +
> + if (err)
> + iounmap((void *)npregs);

Looks OK but while you are at it, could you please also add missing
release_mem_region() on error and on device removal:

newport_addr = dev->resource.start + 0xF0000;
if (!request_mem_region(newport_addr, 0x10000, "Newport"))
return -ENODEV;

npregs = (struct newport_regs *)/* ioremap cannot fail */
ioremap(newport_addr, sizeof(struct newport_regs));
console_lock();
err = do_take_over_console(&newport_con, 0, MAX_NR_CONSOLES - 1, 1);
console_unlock();
return err;
}

static void newport_remove(struct gio_device *dev)
{
give_up_console(&newport_con);
iounmap((void *)npregs);
}

?

> return err;
> }
>

Best regards,
--
Bartlomiej Zolnierkiewicz
Samsung R&D Institute Poland
Samsung Electronics