On 09/07/2015 07:18 PM, Paolo Bonzini wrote:
+static int handle_pcommit(struct kvm_vcpu *vcpu) +{ + /* we never catch pcommit instruct for L1 guest. */ + BUG();Please WARN instead.
Okay.
+ return 1; +} + /* * The exit handlers return 1 if the exit was handled fully and guest execution * may resume. Otherwise they set the kvm_run parameter to indicate what needs @@ -7258,6 +7269,7 @@ static int (*const kvm_vmx_exit_handlers[])(struct kvm_vcpu *vcpu) = { [EXIT_REASON_XSAVES] = handle_xsaves, [EXIT_REASON_XRSTORS] = handle_xrstors, [EXIT_REASON_PML_FULL] = handle_pml_full, + [EXIT_REASON_PCOMMIT] = handle_pcommit, }; static const int kvm_vmx_max_exit_handlers = @@ -7559,6 +7571,8 @@ static bool nested_vmx_exit_handled(struct kvm_vcpu *vcpu) * the XSS exit bitmap in vmcs12. */ return nested_cpu_has2(vmcs12, SECONDARY_EXEC_XSAVES); + case EXIT_REASON_PCOMMIT: + return nested_cpu_has2(vmcs12, SECONDARY_EXEC_PCOMMIT); default: return true; } @@ -8688,6 +8702,10 @@ static void vmx_cpuid_update(struct kvm_vcpu *vcpu) if (best) best->ebx &= ~bit(X86_FEATURE_INVPCID); } + + if (!guest_cpuid_has_pcommit(vcpu) && nested) + vmx->nested.nested_vmx_secondary_ctls_high &= + ~SECONDARY_EXEC_PCOMMIT;Why is this needed?
If pcommit is not allowed in L1 guest, L1 is not allowed to intercept pcommit for L2. BTW, the spec saied: | IA32_VMX_PROCBASED_CTLS2[53] (which enumerates support for the 1-setting of “PCOMMIT exiting”) is | always the same as CPUID.07H:EBX.PCOMMIT[bit 22]. Thus, software can set “PCOMMIT exiting” to 1 | if and only if the PCOMMIT instruction is enumerated via CPUID -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
