Re: [PATCH v5 1/1] x86/acpi, x86/boot: Add multiprocessor wake-up support

[Kuppuswamy, Sathyanarayanan]

On 5/23/21 11:40 PM, Mika Penttilä wrote:
> So this isn't supporting suspend/resume if AP cannot started again?

Yes. You are correct. It can be used only once per AP. Please find the
spec reference below.

/*
 * According to the ACPI specification r6.4, sec 5.2.12.19, the
 * mailbox-based wakeup mechanism cannot be used more than once
 * for the same CPU, so skip sending wake commands to already
 * awake CPU.
 */

--
Sathyanarayanan Kuppuswamy
Linux Kernel Developer