This is a note to let you know that I've just added the patch titled x86/ACPI/boot: Use FADT version to check support for online capable to the 6.1-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: x86-acpi-boot-use-fadt-version-to-check-support-for-online-capable.patch and it can be found in the queue-6.1 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From a74fabfbd1b7013045afc8cc541e6cab3360ccb5 Mon Sep 17 00:00:00 2001 From: Mario Limonciello <mario.limonciello@xxxxxxx> Date: Wed, 29 Mar 2023 12:45:35 -0500 Subject: x86/ACPI/boot: Use FADT version to check support for online capable From: Mario Limonciello <mario.limonciello@xxxxxxx> 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@xxxxxxxxxx> Reported-by: Borislav Petkov <bp@xxxxxxxxx> Signed-off-by: Mario Limonciello <mario.limonciello@xxxxxxx> Signed-off-by: Borislav Petkov (AMD) <bp@xxxxxxxxx> Cc: <stable@xxxxxxxxxx> Link: https://lore.kernel.org/r/943d2445-84df-d939-f578-5d8240d342cc@xxxxxxxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- 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, Patches currently in stable-queue which might be from mario.limonciello@xxxxxxx are queue-6.1/platform-x86-think-lmi-clean-up-display-of-current_v.patch queue-6.1/platform-x86-think-lmi-fix-memory-leak-when-showing-.patch queue-6.1/platform-x86-think-lmi-fix-memory-leaks-when-parsing.patch queue-6.1/x86-acpi-boot-use-fadt-version-to-check-support-for-online-capable.patch