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Date:   Mon, 22 Feb 2021 12:23:04 +0000
Message-ID: <87ft1o1ec7.wl-maz@kernel.org>
From:   Marc Zyngier <maz@kernel.org>
To:     Mark Rutland <mark.rutland@arm.com>
Cc:     linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
        catalin.marinas@arm.com, james.morse@arm.com, marcan@marcan.st,
        tglx@linutronix.de, will@kernel.org
Subject: Re: [PATCH 5/8] arm64: irq: add a default handle_irq panic function
In-Reply-To: <20210222120614.GC70951@C02TD0UTHF1T.local>
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On Mon, 22 Feb 2021 12:06:14 +0000,
Mark Rutland <mark.rutland@arm.com> wrote:
> 
> On Mon, Feb 22, 2021 at 11:43:13AM +0000, Marc Zyngier wrote:

[...]

> > As I said, it's not a big deal. I doubt that we'll see default_handle_irq()
> > exploding in practice. But the real nit here is the difference of treatment
> > between IRQ and FIQ. *IF* we ever get a system that only signals its
> > interrupt as FIQ (and I don't see why we'd forbid that), then we would
> 
> That's a fair point.
> 
> For consistency, we could remove the init_IRQ() panic() and instead log
> the registered handlers, e.g.
> 
> | pr_info("Root IRQ handler is %ps\n", handle_arch_irq);
> | pr_info("Root FIQ handler is %ps\n", handle_arch_fiq);
> 
> ... or do that inside the set_handle_{irq,fiq}() functions. That way the
> messages (or absence thereof) would be sufficient to diagnose the lack
> of a root IRQ/FIQ handler when IRQ/FIQ happens to be quiescent.
> 
> Does that sound any better?

Yup, I quite like the second variant (using set_handle_{irq,fiq}()).

Thanks,

	M.

-- 
Without deviation from the norm, progress is not possible.