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Date:   Wed, 21 Apr 2021 18:15:16 +0100
From:   Sudeep Holla <sudeep.holla@arm.com>
To:     Marc Zyngier <maz@kernel.org>
Cc:     Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>,
        Hanjun Guo <guohanjun@huawei.com>,
        dann frazier <dann.frazier@canonical.com>,
        Fu Wei <wefu@redhat.com>, Len Brown <lenb@kernel.org>,
        "Rafael J. Wysocki" <rjw@rjwysocki.net>,
        linux-acpi@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        linux-kernel@vger.kernel.org, kernel-team@android.com,
        Sudeep Holla <sudeep.holla@arm.com>
Subject: Re: [PATCH 2/2] ACPI: irq: Prevent unregistering of GIC SGIs
Message-ID: <20210421171516.hg3ex7jqigqjqa6i@bogus>
References: <20210421164317.1718831-1-maz@kernel.org>
 <20210421164317.1718831-3-maz@kernel.org>
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On Wed, Apr 21, 2021 at 05:43:17PM +0100, Marc Zyngier wrote:
> When using ACPI on arm64, which implies the GIC IRQ model, no
> table should ever provide a GSI number in the range [0:15],
> as these are reserved for IPIs.
>
> However, drivers tend to call acpi_unregister_gsi() with any
> random GSI number provided by half baked tables, which results
> in an exploding kernel when its IPIs have been unconfigured.
>
> In order to catch this, check for the silly case early, warn
> that something is going wrong and avoid the above disaster.
>

Reviewed-by: Sudeep Holla <sudeep.holla@arm.com>

Just curious if this is just precaution or do we have a platform doing
something stupid like this ?

--
Regards,
Sudeep