| Message ID | 78dee5850404a2db1bf5b4ec611c286cc5bd6df6.1735590556.git.huibo.wang@amd.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | KVM: SVM: Make VMGEXIT GHCB exit codes more readable | expand |
On 12/30/2024 2:36 PM, Melody Wang wrote: > Provide helpers to set the error code when converting VMGEXIT SW_EXITINFO1 and > SW_EXITINFO2 codes from plain numbers to proper defines. Add comments for > better code readability. > > No functionality changed. > > Suggested-by: Sean Christopherson <seanjc@google.com> > Signed-off-by: Melody Wang <huibo.wang@amd.com> > --- > arch/x86/kvm/svm/sev.c | 36 +++++++++++++++++++----------------- > arch/x86/kvm/svm/svm.c | 6 +----- > arch/x86/kvm/svm/svm.h | 29 +++++++++++++++++++++++++++++ > 3 files changed, 49 insertions(+), 22 deletions(-) > > diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c > index 59a0d8292f87..6e2a0f0b4753 100644 > --- a/arch/x86/kvm/svm/sev.c > +++ b/arch/x86/kvm/svm/sev.c > @@ -3420,8 +3420,7 @@ static int sev_es_validate_vmgexit(struct vcpu_svm *svm) > dump_ghcb(svm); > } > > - ghcb_set_sw_exit_info_1(svm->sev_es.ghcb, GHCB_HV_RESP_MALFORMED_INPUT); > - ghcb_set_sw_exit_info_2(svm->sev_es.ghcb, reason); > + svm_vmgexit_bad_input(svm, reason); > > /* Resume the guest to "return" the error code. */ > return 1; > @@ -3564,8 +3563,7 @@ static int setup_vmgexit_scratch(struct vcpu_svm *svm, bool sync, u64 len) > return 0; > > e_scratch: > - ghcb_set_sw_exit_info_1(svm->sev_es.ghcb, GHCB_HV_RESP_MALFORMED_INPUT); > - ghcb_set_sw_exit_info_2(svm->sev_es.ghcb, GHCB_ERR_INVALID_SCRATCH_AREA); > + svm_vmgexit_bad_input(svm, GHCB_ERR_INVALID_SCRATCH_AREA); > > return 1; > } > @@ -3658,7 +3656,14 @@ static void snp_complete_psc(struct vcpu_svm *svm, u64 psc_ret) > svm->sev_es.psc_inflight = 0; > svm->sev_es.psc_idx = 0; > svm->sev_es.psc_2m = false; > - ghcb_set_sw_exit_info_2(svm->sev_es.ghcb, psc_ret); > + > + /* > + * A value of zero in SW_EXITINFO1 does not guarantee that > + * all operations have completed or completed successfully. > + * PSC requests always get a "no action" response, with a > + * PSC-specific return code in SW_EXITINFO2. > + */ I feel you should make this more clearer by mentioning "no action" corresponds to SW_EXITINFO1. > + svm_vmgexit_no_action(svm, psc_ret); > } > > static void __snp_complete_one_psc(struct vcpu_svm *svm) > @@ -4055,7 +4060,7 @@ static int snp_handle_guest_req(struct vcpu_svm *svm, gpa_t req_gpa, gpa_t resp_ > goto out_unlock; > } > > - ghcb_set_sw_exit_info_2(svm->sev_es.ghcb, SNP_GUEST_ERR(0, fw_err)); > + svm_vmgexit_no_action(svm, SNP_GUEST_ERR(0, fw_err)); > You missed out on Sean's suggestion to add the following comment. /* * No action is requested from KVM, even if the request failed due to a * firmware error. */ I feel this comment is necessary since you are calling svm_vmgexit_no_action() that sheds light on SW_EXITINFO1. Thanks, Pavan > ret = 1; /* resume guest */ > > @@ -4111,8 +4116,7 @@ static int snp_handle_ext_guest_req(struct vcpu_svm *svm, gpa_t req_gpa, gpa_t r > return snp_handle_guest_req(svm, req_gpa, resp_gpa); > > request_invalid: > - ghcb_set_sw_exit_info_1(svm->sev_es.ghcb, GHCB_HV_RESP_MALFORMED_INPUT); > - ghcb_set_sw_exit_info_2(svm->sev_es.ghcb, GHCB_ERR_INVALID_INPUT); > + svm_vmgexit_bad_input(svm, GHCB_ERR_INVALID_INPUT); > return 1; /* resume guest */ > } > > @@ -4304,8 +4308,7 @@ int sev_handle_vmgexit(struct kvm_vcpu *vcpu) > if (ret) > return ret; > > - ghcb_set_sw_exit_info_1(svm->sev_es.ghcb, GHCB_HV_RESP_NO_ACTION); > - ghcb_set_sw_exit_info_2(svm->sev_es.ghcb, 0); > + svm_vmgexit_success(svm, 0); > > exit_code = kvm_ghcb_get_sw_exit_code(control); > switch (exit_code) { > @@ -4349,20 +4352,20 @@ int sev_handle_vmgexit(struct kvm_vcpu *vcpu) > break; > case 1: > /* Get AP jump table address */ > - ghcb_set_sw_exit_info_2(svm->sev_es.ghcb, sev->ap_jump_table); > + svm_vmgexit_success(svm, sev->ap_jump_table); > break; > default: > pr_err("svm: vmgexit: unsupported AP jump table request - exit_info_1=%#llx\n", > control->exit_info_1); > - ghcb_set_sw_exit_info_1(svm->sev_es.ghcb, GHCB_HV_RESP_MALFORMED_INPUT); > - ghcb_set_sw_exit_info_2(svm->sev_es.ghcb, GHCB_ERR_INVALID_INPUT); > + svm_vmgexit_bad_input(svm, GHCB_ERR_INVALID_INPUT); > } > > ret = 1; > break; > } > case SVM_VMGEXIT_HV_FEATURES: > - ghcb_set_sw_exit_info_2(svm->sev_es.ghcb, GHCB_HV_FT_SUPPORTED); > + /* Get hypervisor supported features */ > + svm_vmgexit_success(svm, GHCB_HV_FT_SUPPORTED); > > ret = 1; > break; > @@ -4384,8 +4387,7 @@ int sev_handle_vmgexit(struct kvm_vcpu *vcpu) > case SVM_VMGEXIT_AP_CREATION: > ret = sev_snp_ap_creation(svm); > if (ret) { > - ghcb_set_sw_exit_info_1(svm->sev_es.ghcb, GHCB_HV_RESP_MALFORMED_INPUT); > - ghcb_set_sw_exit_info_2(svm->sev_es.ghcb, GHCB_ERR_INVALID_INPUT); > + svm_vmgexit_bad_input(svm, GHCB_ERR_INVALID_INPUT); > } > > ret = 1; > @@ -4622,7 +4624,7 @@ void sev_vcpu_deliver_sipi_vector(struct kvm_vcpu *vcpu, u8 vector) > * Return from an AP Reset Hold VMGEXIT, where the guest will > * set the CS and RIP. Set SW_EXIT_INFO_2 to a non-zero value. > */ > - ghcb_set_sw_exit_info_2(svm->sev_es.ghcb, 1); > + svm_vmgexit_success(svm, 1); > break; > case AP_RESET_HOLD_MSR_PROTO: > /* > diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c > index 0de2bf132056..f8c5c78b917e 100644 > --- a/arch/x86/kvm/svm/svm.c > +++ b/arch/x86/kvm/svm/svm.c > @@ -2977,11 +2977,7 @@ static int svm_complete_emulated_msr(struct kvm_vcpu *vcpu, int err) > if (!err || !sev_es_guest(vcpu->kvm) || WARN_ON_ONCE(!svm->sev_es.ghcb)) > return kvm_complete_insn_gp(vcpu, err); > > - ghcb_set_sw_exit_info_1(svm->sev_es.ghcb, GHCB_HV_RESP_ISSUE_EXCEPTION); > - ghcb_set_sw_exit_info_2(svm->sev_es.ghcb, > - X86_TRAP_GP | > - SVM_EVTINJ_TYPE_EXEPT | > - SVM_EVTINJ_VALID); > + svm_vmgexit_inject_exception(svm, X86_TRAP_GP); > return 1; > } > > diff --git a/arch/x86/kvm/svm/svm.h b/arch/x86/kvm/svm/svm.h > index 43fa6a16eb19..78c8b5fb2bdc 100644 > --- a/arch/x86/kvm/svm/svm.h > +++ b/arch/x86/kvm/svm/svm.h > @@ -588,6 +588,35 @@ static inline bool is_vnmi_enabled(struct vcpu_svm *svm) > return false; > } > > +static inline void svm_vmgexit_set_return_code(struct vcpu_svm *svm, > + u64 response, u64 data) > +{ > + ghcb_set_sw_exit_info_1(svm->sev_es.ghcb, response); > + ghcb_set_sw_exit_info_2(svm->sev_es.ghcb, data); > +} > + > +static inline void svm_vmgexit_inject_exception(struct vcpu_svm *svm, u8 vector) > +{ > + u64 data = SVM_EVTINJ_VALID | SVM_EVTINJ_TYPE_EXEPT | vector; > + > + svm_vmgexit_set_return_code(svm, GHCB_HV_RESP_ISSUE_EXCEPTION, data); > +} > + > +static inline void svm_vmgexit_bad_input(struct vcpu_svm *svm, u64 suberror) > +{ > + svm_vmgexit_set_return_code(svm, GHCB_HV_RESP_MALFORMED_INPUT, suberror); > +} > + > +static inline void svm_vmgexit_success(struct vcpu_svm *svm, u64 data) > +{ > + svm_vmgexit_set_return_code(svm, GHCB_HV_RESP_NO_ACTION, data); > +} > + > +static inline void svm_vmgexit_no_action(struct vcpu_svm *svm, u64 data) > +{ > + svm_vmgexit_set_return_code(svm, GHCB_HV_RESP_NO_ACTION, data); > +} > + > /* svm.c */ > #define MSR_INVALID 0xffffffffU >
diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c index 59a0d8292f87..6e2a0f0b4753 100644 --- a/arch/x86/kvm/svm/sev.c +++ b/arch/x86/kvm/svm/sev.c @@ -3420,8 +3420,7 @@ static int sev_es_validate_vmgexit(struct vcpu_svm *svm) dump_ghcb(svm); } - ghcb_set_sw_exit_info_1(svm->sev_es.ghcb, GHCB_HV_RESP_MALFORMED_INPUT); - ghcb_set_sw_exit_info_2(svm->sev_es.ghcb, reason); + svm_vmgexit_bad_input(svm, reason); /* Resume the guest to "return" the error code. */ return 1; @@ -3564,8 +3563,7 @@ static int setup_vmgexit_scratch(struct vcpu_svm *svm, bool sync, u64 len) return 0; e_scratch: - ghcb_set_sw_exit_info_1(svm->sev_es.ghcb, GHCB_HV_RESP_MALFORMED_INPUT); - ghcb_set_sw_exit_info_2(svm->sev_es.ghcb, GHCB_ERR_INVALID_SCRATCH_AREA); + svm_vmgexit_bad_input(svm, GHCB_ERR_INVALID_SCRATCH_AREA); return 1; } @@ -3658,7 +3656,14 @@ static void snp_complete_psc(struct vcpu_svm *svm, u64 psc_ret) svm->sev_es.psc_inflight = 0; svm->sev_es.psc_idx = 0; svm->sev_es.psc_2m = false; - ghcb_set_sw_exit_info_2(svm->sev_es.ghcb, psc_ret); + + /* + * A value of zero in SW_EXITINFO1 does not guarantee that + * all operations have completed or completed successfully. + * PSC requests always get a "no action" response, with a + * PSC-specific return code in SW_EXITINFO2. + */ + svm_vmgexit_no_action(svm, psc_ret); } static void __snp_complete_one_psc(struct vcpu_svm *svm) @@ -4055,7 +4060,7 @@ static int snp_handle_guest_req(struct vcpu_svm *svm, gpa_t req_gpa, gpa_t resp_ goto out_unlock; } - ghcb_set_sw_exit_info_2(svm->sev_es.ghcb, SNP_GUEST_ERR(0, fw_err)); + svm_vmgexit_no_action(svm, SNP_GUEST_ERR(0, fw_err)); ret = 1; /* resume guest */ @@ -4111,8 +4116,7 @@ static int snp_handle_ext_guest_req(struct vcpu_svm *svm, gpa_t req_gpa, gpa_t r return snp_handle_guest_req(svm, req_gpa, resp_gpa); request_invalid: - ghcb_set_sw_exit_info_1(svm->sev_es.ghcb, GHCB_HV_RESP_MALFORMED_INPUT); - ghcb_set_sw_exit_info_2(svm->sev_es.ghcb, GHCB_ERR_INVALID_INPUT); + svm_vmgexit_bad_input(svm, GHCB_ERR_INVALID_INPUT); return 1; /* resume guest */ } @@ -4304,8 +4308,7 @@ int sev_handle_vmgexit(struct kvm_vcpu *vcpu) if (ret) return ret; - ghcb_set_sw_exit_info_1(svm->sev_es.ghcb, GHCB_HV_RESP_NO_ACTION); - ghcb_set_sw_exit_info_2(svm->sev_es.ghcb, 0); + svm_vmgexit_success(svm, 0); exit_code = kvm_ghcb_get_sw_exit_code(control); switch (exit_code) { @@ -4349,20 +4352,20 @@ int sev_handle_vmgexit(struct kvm_vcpu *vcpu) break; case 1: /* Get AP jump table address */ - ghcb_set_sw_exit_info_2(svm->sev_es.ghcb, sev->ap_jump_table); + svm_vmgexit_success(svm, sev->ap_jump_table); break; default: pr_err("svm: vmgexit: unsupported AP jump table request - exit_info_1=%#llx\n", control->exit_info_1); - ghcb_set_sw_exit_info_1(svm->sev_es.ghcb, GHCB_HV_RESP_MALFORMED_INPUT); - ghcb_set_sw_exit_info_2(svm->sev_es.ghcb, GHCB_ERR_INVALID_INPUT); + svm_vmgexit_bad_input(svm, GHCB_ERR_INVALID_INPUT); } ret = 1; break; } case SVM_VMGEXIT_HV_FEATURES: - ghcb_set_sw_exit_info_2(svm->sev_es.ghcb, GHCB_HV_FT_SUPPORTED); + /* Get hypervisor supported features */ + svm_vmgexit_success(svm, GHCB_HV_FT_SUPPORTED); ret = 1; break; @@ -4384,8 +4387,7 @@ int sev_handle_vmgexit(struct kvm_vcpu *vcpu) case SVM_VMGEXIT_AP_CREATION: ret = sev_snp_ap_creation(svm); if (ret) { - ghcb_set_sw_exit_info_1(svm->sev_es.ghcb, GHCB_HV_RESP_MALFORMED_INPUT); - ghcb_set_sw_exit_info_2(svm->sev_es.ghcb, GHCB_ERR_INVALID_INPUT); + svm_vmgexit_bad_input(svm, GHCB_ERR_INVALID_INPUT); } ret = 1; @@ -4622,7 +4624,7 @@ void sev_vcpu_deliver_sipi_vector(struct kvm_vcpu *vcpu, u8 vector) * Return from an AP Reset Hold VMGEXIT, where the guest will * set the CS and RIP. Set SW_EXIT_INFO_2 to a non-zero value. */ - ghcb_set_sw_exit_info_2(svm->sev_es.ghcb, 1); + svm_vmgexit_success(svm, 1); break; case AP_RESET_HOLD_MSR_PROTO: /* diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c index 0de2bf132056..f8c5c78b917e 100644 --- a/arch/x86/kvm/svm/svm.c +++ b/arch/x86/kvm/svm/svm.c @@ -2977,11 +2977,7 @@ static int svm_complete_emulated_msr(struct kvm_vcpu *vcpu, int err) if (!err || !sev_es_guest(vcpu->kvm) || WARN_ON_ONCE(!svm->sev_es.ghcb)) return kvm_complete_insn_gp(vcpu, err); - ghcb_set_sw_exit_info_1(svm->sev_es.ghcb, GHCB_HV_RESP_ISSUE_EXCEPTION); - ghcb_set_sw_exit_info_2(svm->sev_es.ghcb, - X86_TRAP_GP | - SVM_EVTINJ_TYPE_EXEPT | - SVM_EVTINJ_VALID); + svm_vmgexit_inject_exception(svm, X86_TRAP_GP); return 1; } diff --git a/arch/x86/kvm/svm/svm.h b/arch/x86/kvm/svm/svm.h index 43fa6a16eb19..78c8b5fb2bdc 100644 --- a/arch/x86/kvm/svm/svm.h +++ b/arch/x86/kvm/svm/svm.h @@ -588,6 +588,35 @@ static inline bool is_vnmi_enabled(struct vcpu_svm *svm) return false; } +static inline void svm_vmgexit_set_return_code(struct vcpu_svm *svm, + u64 response, u64 data) +{ + ghcb_set_sw_exit_info_1(svm->sev_es.ghcb, response); + ghcb_set_sw_exit_info_2(svm->sev_es.ghcb, data); +} + +static inline void svm_vmgexit_inject_exception(struct vcpu_svm *svm, u8 vector) +{ + u64 data = SVM_EVTINJ_VALID | SVM_EVTINJ_TYPE_EXEPT | vector; + + svm_vmgexit_set_return_code(svm, GHCB_HV_RESP_ISSUE_EXCEPTION, data); +} + +static inline void svm_vmgexit_bad_input(struct vcpu_svm *svm, u64 suberror) +{ + svm_vmgexit_set_return_code(svm, GHCB_HV_RESP_MALFORMED_INPUT, suberror); +} + +static inline void svm_vmgexit_success(struct vcpu_svm *svm, u64 data) +{ + svm_vmgexit_set_return_code(svm, GHCB_HV_RESP_NO_ACTION, data); +} + +static inline void svm_vmgexit_no_action(struct vcpu_svm *svm, u64 data) +{ + svm_vmgexit_set_return_code(svm, GHCB_HV_RESP_NO_ACTION, data); +} + /* svm.c */ #define MSR_INVALID 0xffffffffU
Provide helpers to set the error code when converting VMGEXIT SW_EXITINFO1 and SW_EXITINFO2 codes from plain numbers to proper defines. Add comments for better code readability. No functionality changed. Suggested-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Melody Wang <huibo.wang@amd.com> --- arch/x86/kvm/svm/sev.c | 36 +++++++++++++++++++----------------- arch/x86/kvm/svm/svm.c | 6 +----- arch/x86/kvm/svm/svm.h | 29 +++++++++++++++++++++++++++++ 3 files changed, 49 insertions(+), 22 deletions(-)