Re: [RFC v2 14/17] x86/apic: Add kexec support for Secure AVIC

Neeraj Upadhyay
2025-04-02T02:40:39Z

On 4/2/2025 12:01 AM, Thomas Gleixner wrote:
> On Tue, Apr 01 2025 at 16:05, Neeraj Upadhyay wrote:
>
>> On 3/21/2025 9:18 PM, Thomas Gleixner wrote:
>>> On Wed, Feb 26 2025 at 14:35, Neeraj Upadhyay wrote:
>>>>
>>>> +/*
>>>> + * Unregister GPA of the Secure AVIC backing page.
>>>> + *
>>>> + * @apic_id: APIC ID of the vCPU. Use -1ULL for the current vCPU
>>>
>>> Yes, -1ULL is really a sensible value - NOT. Ever thought about
>>> signed/unsigned?
>>
>>
>> In table "Table 7: List of Supported Non-Automatic Events" of GHCB spec [1],
>> 0xffff_ffff_ffff_ffff is used for Secure AVIC GHCB event
>>
>> "RAX will have the APIC ID of the target vCPU or 0xffff_ffff_ffff_ffff
>> for the vCPU doing the call"
>>
>> I am using -1ULL for that here.
>
> Which is a horrible construct, while ~0ULL is not.

Got it. Will replace with ~0ULL.

- Neeraj