From: Mario Limonciello mario.limonciello@amd.com
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 eric.devolder@oracle.com Reported-by: Borislav Petkov bp@alien8.de Signed-off-by: Mario Limonciello mario.limonciello@amd.com Signed-off-by: Borislav Petkov (AMD) bp@alien8.de Cc: stable@kernel.org Link: https://lore.kernel.org/r/943d2445-84df-d939-f578-5d8240d342cc@unsolicited.n... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/x86/kernel/acpi/boot.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)
--- 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
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,