Received-SPF: pass (google.com: domain of linux-wireless-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Date:   Mon, 16 May 2022 12:18:14 +0200
From:   Lukas Wunner <lukas@wunner.de>
To:     Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc:     linux-kernel@vger.kernel.org, Thomas Gleixner <tglx@linutronix.de>,
        Bartosz Golaszewski <brgl@bgdev.pl>,
        Basavaraj Natikar <Basavaraj.Natikar@amd.com>,
        Hans de Goede <hdegoede@redhat.com>,
        Linus Walleij <linus.walleij@linaro.org>,
        Mark Gross <markgross@kernel.org>, Michael Buesch <m@bues.ch>,
        Rafa?? Mi??ecki <zajec5@gmail.com>,
        Shyam Sundar S K <Shyam-sundar.S-k@amd.com>,
        linux-gpio@vger.kernel.org, linux-wireless@vger.kernel.org,
        platform-driver-x86@vger.kernel.org
Subject: Re: [RFC PATCH] genirq: Provide generic_handle_domain_irq_safe().
Message-ID: <20220516101814.GA18490@wunner.de>
References: <YnkfWFzvusFFktSt@linutronix.de>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <YnkfWFzvusFFktSt@linutronix.de>
User-Agent: Mutt/1.10.1 (2018-07-13)
Precedence: bulk

On Mon, May 09, 2022 at 04:04:08PM +0200, Sebastian Andrzej Siewior wrote:
> The problem with generic_handle_domain_irq() is that with `threadirqs'
> it will trigger "WARN_ON_ONCE(!in_hardirq())".

Now silenced by:
https://git.kernel.org/linus/792ea6a074ae


> +int generic_handle_domain_irq_safe(struct irq_domain *domain, unsigned int hwirq)
> +{
> +	unsigned long flags;
> +	int ret;
> +
> +	local_irq_save(flags);
> +	ret = handle_irq_desc(irq_resolve_mapping(domain, hwirq));
> +	local_irq_restore(flags);
> +	return ret;
> +}
> +EXPORT_SYMBOL_GPL(generic_handle_domain_irq_safe);

AFAICS you don't need to disable hardirqs at least for the "threadirqs"
case because irq_forced_thread_fn() already does that.


>  drivers/bcma/driver_gpio.c                 |  2 +-
>  drivers/gpio/gpio-mlxbf2.c                 |  6 ++----
>  drivers/pinctrl/pinctrl-amd.c              |  2 +-
>  drivers/platform/x86/intel/int0002_vgpio.c |  3 +--
>  drivers/ssb/driver_gpio.c                  |  6 ++++--

From a quick look, the proper solution for all of those drivers is
probably to just add IRQF_NO_THREAD and be done with it.

Thanks,

Lukas