On 09.10.2025 17:08, Grygorii Strashko wrote:
> On 08.10.25 15:09, Jan Beulich wrote:
>> --- a/xen/arch/x86/hvm/vlapic.c
>> +++ b/xen/arch/x86/hvm/vlapic.c
>> @@ -31,10 +31,13 @@
>> #include <public/hvm/ioreq.h>
>> #include <public/hvm/params.h>
>>
>> -#define LVT_BIAS(reg) (((reg) - APIC_LVTT) >> 4)
>> +#include <../cpu/mcheck/x86_mca.h> /* MCG_CMCI_P */
>
> This include... You probably do not like it also
> It is dependency outside HVM code.
>
> I've been thinking about something like vlapic->caps which can be filed
> before vlapic_init()
> or passed as parameter, but seems x86 toolstack is considered to be able
> overwrite anything,
> including v->arch.vmce.
>
> Seems, no better options here.
Same here, hence why I used it despite not liking it.
>> @@ -697,8 +701,17 @@ int guest_rdmsr_x2apic(const struct vcpu
>> return X86EMUL_EXCEPTION;
>>
>> offset = reg << 4;
>> - if ( offset == APIC_ICR )
>> + switch ( offset )
>> + {
>> + case APIC_ICR:
>> high = (uint64_t)vlapic_read_aligned(vlapic, APIC_ICR2) << 32;
>> + break;
>> +
>> + case APIC_CMCI:
>> + if ( !(v->arch.vmce.mcg_cap & MCG_CMCI_P) )
>
> Could it be done using wrapper, like vmce_has_cmci()?
> As this is Intel specific it's candidate to be opt-out eventually.
Possible. I wanted to limit the churn, hence why I preferred not to introduce
a wrapper. Such an abstraction I wouldn't like to be a function taking a vCPU;
really this should be a domain property imo.
Jan
