From: Sean Christopherson seanjc@google.com
[ Upstream commit fa13680f5668cff05302a2f4753c49334a83a064 ]
Disable SEV and SEV-ES if NPT is disabled. While the APM doesn't clearly state that NPT is mandatory, it's alluded to by:
The guest page tables, managed by the guest, may mark data memory pages as either private or shared, thus allowing selected pages to be shared outside the guest.
And practically speaking, shadow paging can't work since KVM can't read the guest's page tables.
Fixes: e9df09428996 ("KVM: SVM: Add sev module_param") Cc: Brijesh Singh <brijesh.singh@amd.com Cc: Tom Lendacky thomas.lendacky@amd.com Signed-off-by: Sean Christopherson seanjc@google.com Message-Id: 20210422021125.3417167-4-seanjc@google.com Signed-off-by: Paolo Bonzini pbonzini@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org --- arch/x86/kvm/svm/svm.c | 30 +++++++++++++++--------------- 1 file changed, 15 insertions(+), 15 deletions(-)
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c index d5620361eae7..309725151313 100644 --- a/arch/x86/kvm/svm/svm.c +++ b/arch/x86/kvm/svm/svm.c @@ -968,21 +968,6 @@ static __init int svm_hardware_setup(void) kvm_enable_efer_bits(EFER_SVME | EFER_LMSLE); }
- if (IS_ENABLED(CONFIG_KVM_AMD_SEV) && sev) { - sev_hardware_setup(); - } else { - sev = false; - sev_es = false; - } - - svm_adjust_mmio_mask(); - - for_each_possible_cpu(cpu) { - r = svm_cpu_init(cpu); - if (r) - goto err; - } - /* * KVM's MMU doesn't support using 2-level paging for itself, and thus * NPT isn't supported if the host is using 2-level paging since host @@ -997,6 +982,21 @@ static __init int svm_hardware_setup(void) kvm_configure_mmu(npt_enabled, get_max_npt_level(), PG_LEVEL_1G); pr_info("kvm: Nested Paging %sabled\n", npt_enabled ? "en" : "dis");
+ if (IS_ENABLED(CONFIG_KVM_AMD_SEV) && sev && npt_enabled) { + sev_hardware_setup(); + } else { + sev = false; + sev_es = false; + } + + svm_adjust_mmio_mask(); + + for_each_possible_cpu(cpu) { + r = svm_cpu_init(cpu); + if (r) + goto err; + } + if (nrips) { if (!boot_cpu_has(X86_FEATURE_NRIPS)) nrips = false;