linux-kernel - Re: [patch 1/5] pinctrl: samsung: Remove bogus irq

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: Windows password security audit tool. GUI, reports in PDF.

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

Date:   Fri, 30 Jun 2017 11:47:35 +0900
From:   Tomasz Figa <tomasz.figa@...il.com>
To:     Thomas Gleixner <tglx@...utronix.de>,
        Sylwester Nawrocki <s.nawrocki@...sung.com>,
        Krzysztof Kozlowski <krzk@...nel.org>
Cc:     LKML <linux-kernel@...r.kernel.org>,
        Marc Zyngier <marc.zyngier@....com>,
        Linus Walleij <linus.walleij@...aro.org>,
        Brian Norris <briannorris@...omium.org>,
        Heiko Stuebner <heiko@...ech.de>,
        linux-rockchip@...ts.infradead.org,
        Julia Cartwright <julia@...com>,
        "linux-gpio@...r.kernel.org" <linux-gpio@...r.kernel.org>,
        John Keeping <john@...anate.com>,
        Doug Anderson <dianders@...omium.org>,
        Kukjin Kim <kgene@...nel.org>,
        linux-arm-kernel <linux-arm-kernel@...ts.infradead.org>,
        "linux-samsung-soc@...r.kernel.org" 
        <linux-samsung-soc@...r.kernel.org>
Subject: Re: [patch 1/5] pinctrl: samsung: Remove bogus irq_[un]mask from
 resource management

Hi Thomas,

2017-06-30 6:33 GMT+09:00 Thomas Gleixner <tglx@...utronix.de>:
> The irq chip callbacks irq_request/release_resources() have absolutely no
> business with masking and unmasking the irq.
>
> The core code unmasks the interrupt after complete setup and masks it
> before invoking irq_release_resources().
>
> The unmask is actually harmful as it happens before the interrupt is
> completely initialized in __setup_irq().
>
> Remove it.

Good catch, thanks! (Note that the original patch of mine [1] did that
in .irq_startup()/.irq_shutdown(), which was for some reason changed
later, but I don't remember the exact story.)

[1] https://patchwork.kernel.org/patch/4466431/

Acked-by: Tomasz Figa <tomasz.figa@...il.com>

Sylwester, Krzysztof, would you be able to do some basic test?

Best regards,
Tomasz

>
> Fixes: f6a8249f9e55 ("pinctrl: exynos: Lock GPIOs as interrupts when used as EINTs")
> Signed-off-by: Thomas Gleixner <tglx@...utronix.de>
> Cc: Tomasz Figa <tomasz.figa@...il.com>
> Cc: Krzysztof Kozlowski <krzk@...nel.org>
> Cc: Sylwester Nawrocki <s.nawrocki@...sung.com>
> Cc: Linus Walleij <linus.walleij@...aro.org>
> Cc: Kukjin Kim <kgene@...nel.org>
> Cc: linux-arm-kernel@...ts.infradead.org
> Cc: linux-samsung-soc@...r.kernel.org
> Cc: linux-gpio@...r.kernel.org
> ---
>  drivers/pinctrl/samsung/pinctrl-exynos.c |    4 ----
>  1 file changed, 4 deletions(-)
>
> --- a/drivers/pinctrl/samsung/pinctrl-exynos.c
> +++ b/drivers/pinctrl/samsung/pinctrl-exynos.c
> @@ -205,8 +205,6 @@ static int exynos_irq_request_resources(
>
>         spin_unlock_irqrestore(&bank->slock, flags);
>
> -       exynos_irq_unmask(irqd);
> -
>         return 0;
>  }
>
> @@ -226,8 +224,6 @@ static void exynos_irq_release_resources
>         shift = irqd->hwirq * bank_type->fld_width[PINCFG_TYPE_FUNC];
>         mask = (1 << bank_type->fld_width[PINCFG_TYPE_FUNC]) - 1;
>
> -       exynos_irq_mask(irqd);
> -
>         spin_lock_irqsave(&bank->slock, flags);
>
>         con = readl(bank->eint_base + reg_con);
>
>