diff options
| -rw-r--r-- | Documentation/cpu-hotplug.txt | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/Documentation/cpu-hotplug.txt b/Documentation/cpu-hotplug.txt index 9f401350f502..67f733d6f848 100644 --- a/Documentation/cpu-hotplug.txt +++ b/Documentation/cpu-hotplug.txt | |||
| @@ -370,8 +370,10 @@ A: There is no clear spec defined way from ACPI that can give us that | |||
| 370 | CPUs in MADT as hotpluggable CPUS. In the case there are no disabled CPUS | 370 | CPUs in MADT as hotpluggable CPUS. In the case there are no disabled CPUS |
| 371 | we assume 1/2 the number of CPUs currently present can be hotplugged. | 371 | we assume 1/2 the number of CPUs currently present can be hotplugged. |
| 372 | 372 | ||
| 373 | Caveat: Today's ACPI MADT can only provide 256 entries since the apicid field | 373 | Caveat: ACPI MADT can only provide 256 entries in systems with only ACPI 2.0c |
| 374 | in MADT is only 8 bits. | 374 | or earlier ACPI version supported, because the apicid field in MADT is only |
| 375 | 8 bits. From ACPI 3.0, this limitation was removed since the apicid field | ||
| 376 | was extended to 32 bits with x2APIC introduced. | ||
| 375 | 377 | ||
| 376 | User Space Notification | 378 | User Space Notification |
| 377 | 379 | ||