superrob1500
/
mirror-linux
mirror of https://github.com/torvalds/linux
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

x86/ACPI/boot: Use FADT version to check support for online capable 

commit a74fabfbd1 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: aa06e20f1b ("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.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
pull/1175/head
Mario Limonciello 2023-03-29 12:45:35 -05:00 committed by Greg Kroah-Hartman
parent 29e8d76446
commit da429cddab
1 changed files with 5 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
arch/x86/kernel/acpi/boot.c
View File

@ -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,