Hello, On Tue, Jul 07, 2015 at 05:30:24PM +0800, Tang Chen wrote: > From: Gu Zheng <guz.fnst@xxxxxxxxxxxxxx> > > All processors' apicids can be obtained by _MAT method or from MADT in ACPI. > The current code ignores disabled processors and returns -ENODEV. > > After this patch, a new parameter will be added to MADT APIs so that caller > is able to control if disabled processors are ignored. This describes what the patch does but doesn't really explain what the patch is trying to achieve. > @@ -282,8 +282,11 @@ static int acpi_processor_get_info(struct acpi_device *device) > * Extra Processor objects may be enumerated on MP systems with > * less than the max # of CPUs. They should be ignored _iff > * they are physically not present. > + * > + * NOTE: Even if the processor has a cpuid, it may not present because ^ be > + * cpuid <-> apicid mapping is persistent now. Saying "now" is kinda weird as this is how the code is gonna be forever. Thanks. -- tejun -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx"> email@xxxxxxxxx </a>