On 31/10/2018 15:21, Alexander Shishkin wrote:
> Paolo Bonzini writes:
>
>> On 31/10/2018 12:38, Alexander Shishkin wrote:
There is no standard way to tell the guest that the host overrode its
choice to use PT. However, the host will get a PGD/PGE packet around
vmentry and vmexit,
Paolo Bonzini writes:
> On 31/10/2018 12:38, Alexander Shishkin wrote:
>>> There is no standard way to tell the guest that the host overrode its
>>> choice to use PT. However, the host will get a PGD/PGE packet around
>>> vmentry and vmexit, so there _will_ be an indication that the guest
>>> ow
On 31/10/2018 12:38, Alexander Shishkin wrote:
>> There is no standard way to tell the guest that the host overrode its
>> choice to use PT. However, the host will get a PGD/PGE packet around
>> vmentry and vmexit, so there _will_ be an indication that the guest
>> owned the MSRs for that period o
Paolo Bonzini writes:
> On 30/10/2018 11:00, Thomas Gleixner wrote:
>> So at least we need a way for perf on the host to programmatically detect,
>> that 'guest traces itself' is enabled, so it can inject that information
>> into the host data and post processing can tell that. W/o something like
Paolo Bonzini writes:
> On 30/10/2018 12:26, Alexander Shishkin wrote:
>> There is a control in the perf event attribute that enables tracing the
>> guest. If this control is enabled, the kvm needs to stay away from any
>> PT related MSRs.
>
> This cannot happen once the guest has been told it ca
On 30/10/2018 12:26, Alexander Shishkin wrote:
>>> affects directly whether the tracing CPUID leaf can be added to the
>>> guest. Therefore it's not perf that can decide whether to turn it on;
>>> KVM must know it when /dev/kvm is opened, which is why it is a module
>>> parameter.
>
> There is a
On 30/10/2018 11:00, Thomas Gleixner wrote:
> On Mon, 29 Oct 2018, Paolo Bonzini wrote:
>> On 24/10/2018 12:13, Alexander Shishkin wrote:
>>> Luwei Kang writes:
+ /*
+ * Set guest state of MSR_IA32_RTIT_CTL MSR (PT will be disabled
+ * on VM entry when it has been disabled in g
Paolo Bonzini writes:
>> If you "have to enable or disable anything" it means you have to
>> override the default. But the default in this patches is "no change
>> compared to before the patches", leaving tracing of both host and guest
>> entirely to the host, so I don't understand your remark.
On Mon, 29 Oct 2018, Paolo Bonzini wrote:
> On 24/10/2018 12:13, Alexander Shishkin wrote:
> > Luwei Kang writes:
> >> + /*
> >> + * Set guest state of MSR_IA32_RTIT_CTL MSR (PT will be disabled
> >> + * on VM entry when it has been disabled in guest before).
> >> + */
> >> + vmcs_write64(
On 24/10/2018 12:13, Alexander Shishkin wrote:
> Luwei Kang writes:
>
>> +static void pt_guest_enter(struct vcpu_vmx *vmx)
>> +{
>> +if (pt_mode == PT_MODE_SYSTEM)
>> +return;
>> +
>> +/* Save host state before VM entry */
>> +rdmsrl(MSR_IA32_RTIT_CTL, vmx->pt_desc.host.ct
> > +static void pt_guest_enter(struct vcpu_vmx *vmx) {
> > + if (pt_mode == PT_MODE_SYSTEM)
> > + return;
> > +
> > + /* Save host state before VM entry */
> > + rdmsrl(MSR_IA32_RTIT_CTL, vmx->pt_desc.host.ctl);
> > +
> > + /*
> > +* Set guest state of MSR_IA32_RTIT_CTL MSR (
Luwei Kang writes:
> +static void pt_guest_enter(struct vcpu_vmx *vmx)
> +{
> + if (pt_mode == PT_MODE_SYSTEM)
> + return;
> +
> + /* Save host state before VM entry */
> + rdmsrl(MSR_IA32_RTIT_CTL, vmx->pt_desc.host.ctl);
> +
> + /*
> + * Set guest state of MSR_I
12 matches
Mail list logo
