diff options
| author | Ravi Bangoria <ravi.bangoria@amd.com> | 2024-05-31 06:46:43 +0200 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2024-06-03 19:06:48 +0200 |
| commit | d922056215617eedfbdbc29fe49953423686fe5e (patch) | |
| tree | 7711d656d269bf18bb4250299e7f63693f4121a4 /arch | |
| parent | KVM: SEV-ES: Prevent MSR access post VMSA encryption (diff) | |
| download | linux-d922056215617eedfbdbc29fe49953423686fe5e.tar.xz linux-d922056215617eedfbdbc29fe49953423686fe5e.zip | |
KVM: SEV-ES: Disallow SEV-ES guests when X86_FEATURE_LBRV is absent
As documented in APM[1], LBR Virtualization must be enabled for SEV-ES
guests. So, prevent SEV-ES guests when LBRV support is missing.
[1]: AMD64 Architecture Programmer's Manual Pub. 40332, Rev. 4.07 - June
2023, Vol 2, 15.35.2 Enabling SEV-ES.
https://bugzilla.kernel.org/attachment.cgi?id=304653
Fixes: 376c6d285017 ("KVM: SVM: Provide support for SEV-ES vCPU creation/loading")
Signed-off-by: Ravi Bangoria <ravi.bangoria@amd.com>
Message-ID: <20240531044644.768-3-ravi.bangoria@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86/kvm/svm/sev.c | 6 | ||||
| -rw-r--r-- | arch/x86/kvm/svm/svm.c | 16 | ||||
| -rw-r--r-- | arch/x86/kvm/svm/svm.h | 1 |
3 files changed, 14 insertions, 9 deletions
diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c index 0623cfaa7bb0..8b52bbba02c0 100644 --- a/arch/x86/kvm/svm/sev.c +++ b/arch/x86/kvm/svm/sev.c @@ -2406,6 +2406,12 @@ void __init sev_hardware_setup(void) if (!boot_cpu_has(X86_FEATURE_SEV_ES)) goto out; + if (!lbrv) { + WARN_ONCE(!boot_cpu_has(X86_FEATURE_LBRV), + "LBRV must be present for SEV-ES support"); + goto out; + } + /* Has the system been allocated ASIDs for SEV-ES? */ if (min_sev_asid == 1) goto out; diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c index f265361f4518..223a551bf44e 100644 --- a/arch/x86/kvm/svm/svm.c +++ b/arch/x86/kvm/svm/svm.c @@ -215,7 +215,7 @@ int vgif = true; module_param(vgif, int, 0444); /* enable/disable LBR virtualization */ -static int lbrv = true; +int lbrv = true; module_param(lbrv, int, 0444); static int tsc_scaling = true; @@ -5294,6 +5294,12 @@ static __init int svm_hardware_setup(void) nrips = nrips && boot_cpu_has(X86_FEATURE_NRIPS); + if (lbrv) { + if (!boot_cpu_has(X86_FEATURE_LBRV)) + lbrv = false; + else + pr_info("LBR virtualization supported\n"); + } /* * Note, SEV setup consumes npt_enabled and enable_mmio_caching (which * may be modified by svm_adjust_mmio_mask()), as well as nrips. @@ -5347,14 +5353,6 @@ static __init int svm_hardware_setup(void) svm_x86_ops.set_vnmi_pending = NULL; } - - if (lbrv) { - if (!boot_cpu_has(X86_FEATURE_LBRV)) - lbrv = false; - else - pr_info("LBR virtualization supported\n"); - } - if (!enable_pmu) pr_info("PMU virtualization is disabled\n"); diff --git a/arch/x86/kvm/svm/svm.h b/arch/x86/kvm/svm/svm.h index be57213cd295..59bbb8122b75 100644 --- a/arch/x86/kvm/svm/svm.h +++ b/arch/x86/kvm/svm/svm.h @@ -39,6 +39,7 @@ extern int vgif; extern bool intercept_smi; extern bool x2avic_enabled; extern bool vnmi; +extern int lbrv; /* * Clean bits in VMCB. |