Re: [Xen-devel] [PATCH 3/6] x86/vpmu: Remove core2_no_vpmu_ops

[Andrew Cooper <andrew.cooper3@xxxxxxxxxx>]

On 16/11/16 16:27, Boris Ostrovsky wrote:
> On 11/16/2016 07:31 AM, Andrew Cooper wrote:
>> diff --git a/xen/arch/x86/cpu/vpmu.c b/xen/arch/x86/cpu/vpmu.c
>> index a542f4d..1f822ca 100644
>> --- a/xen/arch/x86/cpu/vpmu.c
>> +++ b/xen/arch/x86/cpu/vpmu.c
>> @@ -136,9 +136,10 @@ int vpmu_do_msr(unsigned int msr, uint64_t *msr_content,
>>      const struct arch_vpmu_ops *ops;
>>      int ret = 0;
>>  
>> +    /* Don't leak PMU MSRs to unprivileged domains. */
> This was a somewhat incorrect comment originally and since you are
> moving it then perhaps it's worth adding something along the lines of
> "if VPMU is off or if the privileged domain is profiling whole system".
> Otherwise it gives impression that unprivileged domains never access
> those MSRs.

/*
 * Hide the PMU MSRs if vpmu is not configured, or the hardware domain
 * is profiling the whole system.
 */

?

~Andrew

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
https://lists.xen.org/xen-devel