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Date: Fri, 31 May 2024 18:39:50 +0100
Message-ID: <86plt1lw2h.wl-maz@kernel.org>
From: Marc Zyngier <maz@kernel.org>
To: Hagar Hemdan <hagarhem@amazon.com>,
    Thomas Gleixner <tglx@linutronix.de>
Cc: Maximilian Heyne <mheyne@amazon.de>,
	Norbert Manthey <nmanthey@amazon.de>,
	Eric Auger <eric.auger@redhat.com>,
	<linux-arm-kernel@lists.infradead.org>,
	<linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v4] irqchip/gic-v3-its: Fix potential race condition in its_vlpi_prop_update()
In-Reply-To: <20240531162144.28650-1-hagarhem@amazon.com>
References: <20240531162144.28650-1-hagarhem@amazon.com>
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On Fri, 31 May 2024 17:21:44 +0100,
Hagar Hemdan <hagarhem@amazon.com> wrote:
> 
> its_vlpi_prop_update() calls lpi_write_config() which obtains the
> mapping information for a VLPI without lock held. So it could race
> with its_vlpi_unmap().
> Since all calls from its_irq_set_vcpu_affinity() require the same
> lock to be held. So instead of peppering the locking all over the
> place, we hoist the locking into its_irq_set_vcpu_affinity().

This looks odd. Maybe something along the lines of:

"Since all calls from its_irq_set_vcpu_affinity() require the same
 lock to be held, hoist the locking there instead of peppering it over
 the place."

>
> This bug was discovered using Coverity Static Analysis
> Security Testing (SAST) by Synopsys, Inc.
> 
> Fixes: 015ec0386ab6 ("irqchip/gic-v3-its: Add VLPI configuration handling")
> Suggested-by: Marc Zyngier <maz@kernel.org>
> Signed-off-by: Hagar Hemdan <hagarhem@amazon.com>

With the above addressed,

Reviewed-by: Marc Zyngier <maz@kernel.org>
Cc: stable@vger.kernel.org

Thomas, can you please queue it at your earliest convenience?

Thanks,

	M.

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