From da429cddabe0701469534c8dc7a11e2ccd9e098e Mon Sep 17 00:00:00 2001 From: Mario Limonciello Date: Wed, 29 Mar 2023 12:45:35 -0500 Subject: [PATCH] x86/ACPI/boot: Use FADT version to check support for online capable commit a74fabfbd1b7013045afc8cc541e6cab3360ccb5 upstream. ACPI 6.3 introduced the online capable bit, and also introduced MADT version 5. Latter was used to distinguish whether the offset storing online capable could be used. However ACPI 6.2b has MADT version "45" which is for an errata version of the ACPI 6.2 spec. This means that the Linux code for detecting availability of MADT will mistakenly flag ACPI 6.2b as supporting online capable which is inaccurate as it's an ACPI 6.3 feature. Instead use the FADT major and minor revision fields to distinguish this. [ bp: Massage. ] Fixes: aa06e20f1be6 ("x86/ACPI: Don't add CPUs that are not online capable") Reported-by: Eric DeVolder Reported-by: Borislav Petkov Signed-off-by: Mario Limonciello Signed-off-by: Borislav Petkov (AMD) Cc: Link: https://lore.kernel.org/r/943d2445-84df-d939-f578-5d8240d342cc@unsolicited.net Signed-off-by: Greg Kroah-Hartman --- arch/x86/kernel/acpi/boot.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/arch/x86/kernel/acpi/boot.c b/arch/x86/kernel/acpi/boot.c index ee45e0e..0f76207 100644 --- a/arch/x86/kernel/acpi/boot.c +++ b/arch/x86/kernel/acpi/boot.c @@ -146,7 +146,11 @@ static int __init acpi_parse_madt(struct acpi_table_header *table) pr_debug("Local APIC address 0x%08x\n", madt->address); } - if (madt->header.revision >= 5) + + /* ACPI 6.3 and newer support the online capable bit. */ + if (acpi_gbl_FADT.header.revision > 6 || + (acpi_gbl_FADT.header.revision == 6 && + acpi_gbl_FADT.minor_revision >= 3)) acpi_support_online_capable = true; default_acpi_madt_oem_check(madt->header.oem_id, -- 2.7.4