Re: [PATCH 2/2] ACPI: irq: Prevent unregistering of GIC SGIs

From: Sudeep Holla
Date: Wed Apr 21 2021 - 13:15:40 EST


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@xxxxxxx>

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

--
Regards,
Sudeep