[PATCH 1/2] ACPI: GTDT: Don't corrupt interrupt mappings on watchdow probe failure

[Sudeep Holla]

(with stable email fixed, but may need separate posting anyways)

On Wed, Apr 21, 2021 at 05:43:16PM +0100, Marc Zyngier wrote:
> When failing the driver probe because of invalid firmware properties,
> the GTDT driver unmaps the interrupt that it mapped earlier.
> 
> However, it never checks whether the mapping of the interrupt actially
> succeeded. Even more, should the firmware report an illegal interrupt
> number that overlaps with the GIC SGI range, this can result in an
> IPI being unmapped, and subsequent fireworks (as reported by Dann
> Frazier).
> 
> Rework the driver to have a slightly saner behaviour and actually
> check whether the interrupt has been mapped before unmapping things.
> 
> Reported-by: dann frazier <dann.frazier at canonical.com>
> Fixes: ca9ae5ec4ef0 ("acpi/arm64: Add SBSA Generic Watchdog support in GTDT driver")
> Signed-off-by: Marc Zyngier <maz at kernel.org>
> Link: https://lore.kernel.org/r/YH87dtTfwYgavusz@xps13.dannf
> Cc: stable at vgerlkernel.org
                ^^^

I thought I messed up while replying with my fat fingers, but here is the
culprit. I got mail delivery failure to my reply, thought I will let you
know as it may be difficult to notice this when using git send-email.

-- 
Regards,
Sudeep