Re: [PATCH v2 1/3] x86/vmx: implement Bus Lock detection

[Jan Beulich <jbeulich@suse.com>]

On 06.06.2022 15:27, Andrew Cooper wrote:
> On 26/05/2022 12:11, Roger Pau Monne wrote:
>> diff --git a/xen/arch/x86/hvm/vmx/vmx.c b/xen/arch/x86/hvm/vmx/vmx.c
>> index f08a00dcbb..476ab72463 100644
>> --- a/xen/arch/x86/hvm/vmx/vmx.c
>> +++ b/xen/arch/x86/hvm/vmx/vmx.c
>> @@ -4065,6 +4065,16 @@ void vmx_vmexit_handler(struct cpu_user_regs *regs)
>>  
>>      if ( unlikely(exit_reason & VMX_EXIT_REASONS_FAILED_VMENTRY) )
>>          return vmx_failed_vmentry(exit_reason, regs);
>> +    if ( unlikely(exit_reason & VMX_EXIT_REASONS_BUS_LOCK) )
>> +    {
>> +        /*
>> +         * Delivery of Bus Lock VM exit was pre-empted by a higher priority VM
>> +         * exit.
>> +         */
>> +        exit_reason &= ~VMX_EXIT_REASONS_BUS_LOCK;
>> +        if ( exit_reason != EXIT_REASON_BUS_LOCK )
>> +            perfc_incr(buslock);
>> +    }
> 
> I know this post-dates you posting v2, but given the latest update from
> Intel, VMX_EXIT_REASONS_BUS_LOCK will be set on all exits.

Mind me asking what "latest update" you're referring to? Neither SDM nor
ISE have seen a recent update, afaict.

Jan