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charset=UTF-8 Content-Transfer-Encoding: 7bit On 30.10.2024 13:03, Alejandro Vallejo wrote: > On Wed Oct 30, 2024 at 6:37 AM GMT, Jan Beulich wrote: >> On 29.10.2024 21:30, Andrew Cooper wrote: >>> On 21/10/2024 4:45 pm, Alejandro Vallejo wrote: >>>> @@ -310,19 +309,16 @@ void guest_cpuid(const struct vcpu *v, uint32_t leaf, >>>> break; >>>> >>>> case 0xb: >>>> - /* >>>> - * In principle, this leaf is Intel-only. In practice, it is tightly >>>> - * coupled with x2apic, and we offer an x2apic-capable APIC emulation >>>> - * to guests on AMD hardware as well. >>>> - * >>>> - * TODO: Rework topology logic. >>>> - */ >>>> if ( p->basic.x2apic ) >>>> { >>>> *(uint8_t *)&res->c = subleaf; >>>> >>>> - /* Fix the x2APIC identifier. */ >>>> - res->d = v->vcpu_id * 2; >>>> + /* >>>> + * Fix the x2APIC identifier. The PV side is nonsensical, but >>>> + * we've always shown it like this so it's kept for compat. >>>> + */ >>> >>> In hindsight I should changed "Fix the x2APIC identifier." when I >>> reworked this logic, but oh well - better late than never. >>> >>> /* The x2APIC_ID is per-vCPU, and fixed irrespective of the requested >>> subleaf. */ >> >> Can we perhaps avoid "fix" in this comment? "Adjusted", "overwritten", or >> some such ought to do, without carrying a hint towards some bug somewhere. > > I understood "fix" there as "pin" rather than "unbreak". Oh, right - that possible meaning escaped me. Jan