linux-kernel - Re: [PATCH] pinctrl: renesas: rzg2l: Execute atomically the interrupt configuration

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: Thu, 14 Mar 2024 15:31:16 +0100
From: Geert Uytterhoeven <geert@...ux-m68k.org>
To: claudiu beznea <claudiu.beznea@...on.dev>
Cc: linus.walleij@...aro.org, linux-renesas-soc@...r.kernel.org, 
	linux-gpio@...r.kernel.org, linux-kernel@...r.kernel.org, 
	Claudiu Beznea <claudiu.beznea.uj@...renesas.com>
Subject: Re: [PATCH] pinctrl: renesas: rzg2l: Execute atomically the interrupt configuration

Hi Claudiu,

On Thu, Mar 14, 2024 at 3:11 PM claudiu beznea <claudiu.beznea@...on.dev> wrote:
> On 14.03.2024 15:21, Geert Uytterhoeven wrote:
> > On Thu, Mar 7, 2024 at 12:25 PM Claudiu <claudiu.beznea@...on.dev> wrote:
> >> From: Claudiu Beznea <claudiu.beznea.uj@...renesas.com>
> >>
> >> Lockdep detects a possible deadlock as listed below. This is because it
> >> detects the IA55 interrupt controller .irq_eoi() API is called from
> >> interrupt context while configuration-specific API (e.g., .irq_enable())
> >> could be called from process context on resume path (by calling
> >> rzg2l_gpio_irq_restore()). To avoid this, protect the call of
> >> rzg2l_gpio_irq_enable() with spin_lock_irqsave()/spin_unlock_irqrestore().
> >> With this the same approach that is available in __setup_irq() is mimicked
> >> to pinctrl IRQ resume function.
> >
> > You mean __setup_irq() in kernel/irq/manage.c?
>
> Yes!
>
> > That one uses the raw spinlock methods?
>
> Yes! Would you prefer to have raw spinlock here, too?

Most pin control driver needing protection in an irq_enable
method use raw spinlock, so I think it makes sense to follow that.

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@...ux-m68korg

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