On Wed, Feb 07, 2024 at 09:26:27AM -0800, Xin Li wrote: >Add FRED MSRs to the valid passthrough MSR list and set FRED MSRs intercept >based on FRED enumeration. > >Signed-off-by: Xin Li <[email protected]> >Tested-by: Shan Kang <[email protected]>
Reviewed-by: Chao Gao <[email protected]> two nits below. >--- > >Change since v1: >* Enable FRED MSRs intercept if FRED is no longer enumerated in CPUID > (Chao Gao). >--- > arch/x86/kvm/vmx/vmx.c | 17 ++++++++++++++++- > 1 file changed, 16 insertions(+), 1 deletion(-) > >diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c >index 34b6676f60d8..d58ed2d3d379 100644 >--- a/arch/x86/kvm/vmx/vmx.c >+++ b/arch/x86/kvm/vmx/vmx.c >@@ -693,6 +693,9 @@ static bool is_valid_passthrough_msr(u32 msr) > case MSR_LBR_CORE_TO ... MSR_LBR_CORE_TO + 8: > /* LBR MSRs. These are handled in > vmx_update_intercept_for_lbr_msrs() */ > return true; >+ case MSR_IA32_FRED_RSP0 ... MSR_IA32_FRED_CONFIG: >+ /* FRED MSRs should be passthrough to FRED guests only */ This comment sounds weird. It sounds like the code will be something like: if guest supports FRED return true else return false how about "FRED MSRs are pass-thru'd to guests which enumerate FRED"? Or to align with above comment for LBR MSRs, just say /* FRED MSRs. These are handled in vmx_vcpu_config_fred_after_set_cpuid() */ >+ return true; > } > > r = possible_passthrough_msr_slot(msr) != -ENOENT; >@@ -7774,10 +7777,12 @@ static void update_intel_pt_cfg(struct kvm_vcpu *vcpu) > static void vmx_vcpu_config_fred_after_set_cpuid(struct kvm_vcpu *vcpu) > { > struct vcpu_vmx *vmx = to_vmx(vcpu); >+ bool fred_enumerated; > > kvm_governed_feature_check_and_set(vcpu, X86_FEATURE_FRED); >+ fred_enumerated = guest_can_use(vcpu, X86_FEATURE_FRED); > >- if (guest_can_use(vcpu, X86_FEATURE_FRED)) { >+ if (fred_enumerated) { > vm_entry_controls_setbit(vmx, VM_ENTRY_LOAD_IA32_FRED); > secondary_vm_exit_controls_setbit(vmx, > > SECONDARY_VM_EXIT_SAVE_IA32_FRED | >@@ -7788,6 +7793,16 @@ static void vmx_vcpu_config_fred_after_set_cpuid(struct >kvm_vcpu *vcpu) > > SECONDARY_VM_EXIT_SAVE_IA32_FRED | > > SECONDARY_VM_EXIT_LOAD_IA32_FRED); > } >+ >+ vmx_set_intercept_for_msr(vcpu, MSR_IA32_FRED_RSP0, MSR_TYPE_RW, >!fred_enumerated); >+ vmx_set_intercept_for_msr(vcpu, MSR_IA32_FRED_RSP1, MSR_TYPE_RW, >!fred_enumerated); >+ vmx_set_intercept_for_msr(vcpu, MSR_IA32_FRED_RSP2, MSR_TYPE_RW, >!fred_enumerated); >+ vmx_set_intercept_for_msr(vcpu, MSR_IA32_FRED_RSP3, MSR_TYPE_RW, >!fred_enumerated); >+ vmx_set_intercept_for_msr(vcpu, MSR_IA32_FRED_STKLVLS, MSR_TYPE_RW, >!fred_enumerated); >+ vmx_set_intercept_for_msr(vcpu, MSR_IA32_FRED_SSP1, MSR_TYPE_RW, >!fred_enumerated); >+ vmx_set_intercept_for_msr(vcpu, MSR_IA32_FRED_SSP2, MSR_TYPE_RW, >!fred_enumerated); >+ vmx_set_intercept_for_msr(vcpu, MSR_IA32_FRED_SSP3, MSR_TYPE_RW, >!fred_enumerated); >+ vmx_set_intercept_for_msr(vcpu, MSR_IA32_FRED_CONFIG, MSR_TYPE_RW, >!fred_enumerated); Use a for-loop here? e.g., for (i = MSR_IA32_FRED_RSP0; i <= MSR_IA32_FRED_CONFIG; i++) > } > > static void vmx_vcpu_after_set_cpuid(struct kvm_vcpu *vcpu) >-- >2.43.0 > >
