diff options
| author | Kirill A. Shutemov <kirill.shutemov@linux.intel.com> | 2024-06-14 12:58:49 +0300 |
|---|---|---|
| committer | Borislav Petkov (AMD) <bp@alien8.de> | 2024-06-17 17:45:34 +0200 |
| commit | 66e48e491d1e1a0f243ebfcb9639b23de1a5db5e (patch) | |
| tree | fa327aaabde7e3d6b6e03bacfcf51dd5dcb11266 /kernel/cpu.c | |
| parent | 1037e4c53e851682ff8d1ab656567a4d5a333c93 (diff) | |
cpu/hotplug, x86/acpi: Disable CPU offlining for ACPI MADT wakeup
ACPI MADT doesn't allow to offline a CPU after it has been woken up.
Currently, CPU hotplug is prevented based on the confidential computing
attribute which is set for Intel TDX. But TDX is not the only possible user of
the wake up method. Any platform that uses ACPI MADT wakeup method cannot
offline CPU.
Disable CPU offlining on ACPI MADT wakeup enumeration.
This has no visible effects for users: currently, TDX guest is the only platform
that uses the ACPI MADT wakeup method.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Tao Liu <ltao@redhat.com>
Link: https://lore.kernel.org/r/20240614095904.1345461-5-kirill.shutemov@linux.intel.com
Diffstat (limited to 'kernel/cpu.c')
| -rw-r--r-- | kernel/cpu.c | 3 |
1 files changed, 1 insertions, 2 deletions
diff --git a/kernel/cpu.c b/kernel/cpu.c index 4c15b478e2bc..a609385c7f99 100644 --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -1481,8 +1481,7 @@ static int cpu_down_maps_locked(unsigned int cpu, enum cpuhp_state target) * If the platform does not support hotplug, report it explicitly to * differentiate it from a transient offlining failure. */ - if (cc_platform_has(CC_ATTR_HOTPLUG_DISABLED) || - cpu_hotplug_offline_disabled) + if (cpu_hotplug_offline_disabled) return -EOPNOTSUPP; if (cpu_hotplug_disabled) return -EBUSY; |