On 10/30/2011 06:53 PM, Gleb Natapov wrote:
> From: Avi Kivity <avi@xxxxxxxxxx>
>
> Provide a CPUID leaf that describes the emulated PMU.
>
> Signed-off-by: Avi Kivity <avi@xxxxxxxxxx>
> Signed-off-by: Gleb Natapov <gleb@xxxxxxxxxx>
> ---
> arch/x86/kvm/x86.c | 23 ++++++++++++++++++++++-
> 1 files changed, 22 insertions(+), 1 deletions(-)
>
> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
> index 5ea4cb8..56153a9 100644
> --- a/arch/x86/kvm/x86.c
> +++ b/arch/x86/kvm/x86.c
> @@ -2543,6 +2543,28 @@ static void do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function,
> }
> case 9:
> break;
> + case 0xa: { /* Architectural Performance Monitoring */
> + struct x86_pmu_capability cap;
> +
> + perf_get_x86_pmu_capability(&cap);
> +
> + /*
> + * Only support guest architectural pmu on a host
> + * with architectural pmu.
> + */
> + if (!cap.version)
> + memset(&cap, 0, sizeof(cap));
> +
> + entry->eax = min(cap.version, 2)
> + | (cap.num_counters_gp << 8)
> + | (cap.bit_width_gp << 16)
> + | (cap.events_mask_len << 24);
What if num_counters_gp is larger than our array?
> + entry->ebx = cap.events_mask;
> + entry->ecx = 0;
> + entry->edx = cap.num_counters_fixed
> + | (cap.bit_width_fixed << 5);
Ditto.
--
I have a truly marvellous patch that fixes the bug which this
signature is too narrow to contain.
--
To unsubscribe from this list: send the line "unsubscribe kvm" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
