From: Eric DeVolder eric.devolder@oracle.com
commit fed8d8773b8ea68ad99d9eee8c8343bef9da2c2c upstream.
The logic in acpi_is_processor_usable() requires the online capable bit be set for hotpluggable CPUs. The online capable bit has been introduced in ACPI 6.3.
However, for ACPI revisions < 6.3 which do not support that bit, CPUs should be reported as usable, not the other way around.
Reverse the check.
[ bp: Rewrite commit message. ]
Fixes: e2869bd7af60 ("x86/acpi/boot: Do not register processors that cannot be onlined for x2APIC") Suggested-by: Miguel Luis miguel.luis@oracle.com Suggested-by: Boris Ostrovsky boris.ovstrosky@oracle.com Signed-off-by: Eric DeVolder eric.devolder@oracle.com Signed-off-by: Borislav Petkov (AMD) bp@alien8.de Tested-by: David R david@unsolicited.net Cc: stable@kernel.org Link: https://lore.kernel.org/r/20230327191026.3454-2-eric.devolder@oracle.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/x86/kernel/acpi/boot.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
--- a/arch/x86/kernel/acpi/boot.c +++ b/arch/x86/kernel/acpi/boot.c @@ -193,7 +193,8 @@ static bool __init acpi_is_processor_usa if (lapic_flags & ACPI_MADT_ENABLED) return true;
- if (acpi_support_online_capable && (lapic_flags & ACPI_MADT_ONLINE_CAPABLE)) + if (!acpi_support_online_capable || + (lapic_flags & ACPI_MADT_ONLINE_CAPABLE)) return true;
return false;