Re: [PATCH V7 11/18] KVM: x86/pmu: Add IA32_DS_AREA MSR emulation to support guest DS

On 7/2/2021 7:52 PM, Peter Zijlstra wrote:

On Tue, Jun 22, 2021 at 05:42:59PM +0800, Zhu Lingshan wrote:

quoted

diff --git a/arch/x86/events/intel/core.c b/arch/x86/events/intel/core.c
index 190d8d98abf0..b336bcaad626 100644
--- a/arch/x86/events/intel/core.c
+++ b/arch/x86/events/intel/core.c

@@ -21,6 +21,7 @@
  #include <asm/intel_pt.h>
  #include <asm/apic.h>
  #include <asm/cpu_device_id.h>
+#include <asm/kvm_host.h>
  
  #include "../perf_event.h"
  

@@ -3915,6 +3916,7 @@ static struct perf_guest_switch_msr *intel_guest_get_msrs(int *nr, void *data)
  {
  	struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
  	struct perf_guest_switch_msr *arr = cpuc->guest_switch_msrs;
+	struct kvm_pmu *pmu = (struct kvm_pmu *)data;
  	u64 intel_ctrl = hybrid(cpuc->pmu, intel_ctrl);
  	u64 pebs_mask = cpuc->pebs_enabled & x86_pmu.pebs_capable;
  

@@ -3945,9 +3947,15 @@ static struct perf_guest_switch_msr *intel_guest_get_msrs(int *nr, void *data)
  		return arr;
  	}
  
-	if (!x86_pmu.pebs_vmx)
+	if (!pmu || !x86_pmu.pebs_vmx)
  		return arr;
  
+	arr[(*nr)++] = (struct perf_guest_switch_msr){
+		.msr = MSR_IA32_DS_AREA,
+		.host = (unsigned long)cpuc->ds,
+		.guest = pmu->ds_area,
+	};
+
  	arr[*nr] = (struct perf_guest_switch_msr){
  		.msr = MSR_IA32_PEBS_ENABLE,
  		.host = cpuc->pebs_enabled & ~cpuc->intel_ctrl_guest_mask,

s/pmu/kvm_pmu/ or something. pmu is normally a struct pmu *, and having
it be kvm_pmu here is super confusing.

will fix this in V8, Thanks!