ACPI/IORT: Check node revision for PMCG resources
authorRobin Murphy <robin.murphy@arm.com>
Thu, 3 Feb 2022 19:31:24 +0000 (19:31 +0000)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 16 Feb 2022 11:56:19 +0000 (12:56 +0100)
commit65aabd296665f853d9d2805a0c479f99c27a2448
treee0bf57b5949e1730b4d1070e28e13cc1964dcb9e
parent64c37c05f7ad71f13faae1a45800ac4ebfb579cf
ACPI/IORT: Check node revision for PMCG resources

commit da5fb9e1ad3fbf632dce735f1bdad257ca528499 upstream.

The original version of the IORT PMCG definition had an oversight
wherein there was no way to describe the second register page for an
implementation using the recommended RELOC_CTRS feature. Although the
spec was fixed, and the final patches merged to ACPICA and Linux written
against the new version, it seems that some old firmware based on the
original revision has survived and turned up in the wild.

Add a check for the original PMCG definition, and avoid filling in the
second memory resource with nonsense if so. Otherwise it is likely that
something horrible will happen when the PMCG driver attempts to probe.

Reported-by: Michael Petlan <mpetlan@redhat.com>
Fixes: 24e516049360 ("ACPI/IORT: Add support for PMCG")
Cc: <stable@vger.kernel.org> # 5.2.x
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Link: https://lore.kernel.org/r/75628ae41c257fb73588f7bf1c4459160e04be2b.1643916258.git.robin.murphy@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/acpi/arm64/iort.c