linux-kernel - Re: [PATCH] gpio: rcar: handle pm_runtime_get

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Wed, 17 Jun 2020 09:26:47 +0200
From:   Geert Uytterhoeven <geert@...ux-m68k.org>
To:     Navid Emamdoost <navid.emamdoost@...il.com>
Cc:     Linus Walleij <linus.walleij@...aro.org>,
        Bartosz Golaszewski <bgolaszewski@...libre.com>,
        "open list:GPIO SUBSYSTEM" <linux-gpio@...r.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
        Navid Emamdoost <emamd001@....edu>,
        Qiushi Wu <wu000273@....edu>, Kangjie Lu <kjlu@....edu>,
        Stephen McCamant <smccaman@....edu>
Subject: Re: [PATCH] gpio: rcar: handle pm_runtime_get_sync failure case

Hi Navid,

On Fri, Jun 5, 2020 at 4:50 AM Navid Emamdoost
<navid.emamdoost@...il.com> wrote:
> Calling pm_runtime_get_sync increments the counter even in case of
> failure, causing incorrect ref count. Call pm_runtime_put if
> pm_runtime_get_sync fails.
>
> Signed-off-by: Navid Emamdoost <navid.emamdoost@...il.com>

Thanks for your patch!

> --- a/drivers/gpio/gpio-rcar.c
> +++ b/drivers/gpio/gpio-rcar.c
> @@ -250,8 +250,10 @@ static int gpio_rcar_request(struct gpio_chip *chip, unsigned offset)
>         int error;
>
>         error = pm_runtime_get_sync(p->dev);
> -       if (error < 0)
> +       if (error < 0) {
> +               pm_runtime_put(p->dev);

As per [1], I would like to see a call to pm_runtime_put_noidle() instead.

[1] http://lore.kernel.org/r/CAJZ5v0i87NGcy9+kxubScdPDyByr8ypQWcGgBFn+V-wDd69BHQ@mail.gmail.com

>                 return error;
> +       }
>
>         error = pinctrl_gpio_request(chip->base + offset);
>         if (error)

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@...ux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds