| Message ID | 20231016132819.1002933-25-michael.roth@amd.com |
|---|---|
| State | New |
| Headers | show |
| Series | Add AMD Secure Nested Paging (SEV-SNP) Hypervisor Support | expand |
On Mon, Oct 16, 2023 at 08:27:53AM -0500, Michael Roth wrote: > From: Brijesh Singh <brijesh.singh@amd.com> > > The next generation of SEV is called SEV-SNP (Secure Nested Paging). > SEV-SNP builds upon existing SEV and SEV-ES functionality while adding new > hardware based security protection. SEV-SNP adds strong memory encryption > integrity protection to help prevent malicious hypervisor-based attacks > such as data replay, memory re-mapping, and more, to create an isolated > execution environment. > > The SNP feature is added incrementally, the later patches adds a new module > parameters that can be used to enabled SEV-SNP in the KVM. This sentence can simply go to /dev/null. > Signed-off-by: Brijesh Singh <brijesh.singh@amd.com> > Signed-off-by: Ashish Kalra <ashish.kalra@amd.com> > --- > arch/x86/kvm/svm/sev.c | 10 ++++++++++ > arch/x86/kvm/svm/svm.h | 8 ++++++++ > 2 files changed, 18 insertions(+) > > diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c > index 1cfb9232fc74..4eefc168ebb3 100644 > --- a/arch/x86/kvm/svm/sev.c > +++ b/arch/x86/kvm/svm/sev.c > @@ -59,10 +59,14 @@ module_param_named(sev_es, sev_es_enabled, bool, 0444); > /* enable/disable SEV-ES DebugSwap support */ > static bool sev_es_debug_swap_enabled = true; > module_param_named(debug_swap, sev_es_debug_swap_enabled, bool, 0444); > + > +/* enable/disable SEV-SNP support */ Useless comment. > +static bool sev_snp_enabled; > #else > #define sev_enabled false > #define sev_es_enabled false > #define sev_es_debug_swap_enabled false > +#define sev_snp_enabled false > #endif /* CONFIG_KVM_AMD_SEV */ > > #define AP_RESET_HOLD_NONE 0 > @@ -2186,6 +2190,7 @@ void __init sev_hardware_setup(void) > { > #ifdef CONFIG_KVM_AMD_SEV > unsigned int eax, ebx, ecx, edx, sev_asid_count, sev_es_asid_count; > + bool sev_snp_supported = false; > bool sev_es_supported = false; > bool sev_supported = false; > > @@ -2261,6 +2266,10 @@ void __init sev_hardware_setup(void) > sev_es_asid_count = min_sev_asid - 1; > WARN_ON_ONCE(misc_cg_set_capacity(MISC_CG_RES_SEV_ES, sev_es_asid_count)); > sev_es_supported = true; > + sev_snp_supported = sev_snp_enabled && cpu_feature_enabled(X86_FEATURE_SEV_SNP); > + > + pr_info("SEV-ES %ssupported: %u ASIDs\n", > + sev_snp_supported ? "and SEV-SNP " : "", sev_es_asid_count); Why like this? > > out: Here, below the "out:" label you're already dumping SEV and -ES status. Just do SNP exactly the same. > if (boot_cpu_has(X86_FEATURE_SEV)) > @@ -2277,6 +2286,7 @@ void __init sev_hardware_setup(void) > if (!sev_es_enabled || !cpu_feature_enabled(X86_FEATURE_DEBUG_SWAP) || > !cpu_feature_enabled(X86_FEATURE_NO_NESTED_DATA_BP)) > sev_es_debug_swap_enabled = false; > + sev_snp_enabled = sev_snp_supported; > #endif > }
diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c index 1cfb9232fc74..4eefc168ebb3 100644 --- a/arch/x86/kvm/svm/sev.c +++ b/arch/x86/kvm/svm/sev.c @@ -59,10 +59,14 @@ module_param_named(sev_es, sev_es_enabled, bool, 0444); /* enable/disable SEV-ES DebugSwap support */ static bool sev_es_debug_swap_enabled = true; module_param_named(debug_swap, sev_es_debug_swap_enabled, bool, 0444); + +/* enable/disable SEV-SNP support */ +static bool sev_snp_enabled; #else #define sev_enabled false #define sev_es_enabled false #define sev_es_debug_swap_enabled false +#define sev_snp_enabled false #endif /* CONFIG_KVM_AMD_SEV */ #define AP_RESET_HOLD_NONE 0 @@ -2186,6 +2190,7 @@ void __init sev_hardware_setup(void) { #ifdef CONFIG_KVM_AMD_SEV unsigned int eax, ebx, ecx, edx, sev_asid_count, sev_es_asid_count; + bool sev_snp_supported = false; bool sev_es_supported = false; bool sev_supported = false; @@ -2261,6 +2266,10 @@ void __init sev_hardware_setup(void) sev_es_asid_count = min_sev_asid - 1; WARN_ON_ONCE(misc_cg_set_capacity(MISC_CG_RES_SEV_ES, sev_es_asid_count)); sev_es_supported = true; + sev_snp_supported = sev_snp_enabled && cpu_feature_enabled(X86_FEATURE_SEV_SNP); + + pr_info("SEV-ES %ssupported: %u ASIDs\n", + sev_snp_supported ? "and SEV-SNP " : "", sev_es_asid_count); out: if (boot_cpu_has(X86_FEATURE_SEV)) @@ -2277,6 +2286,7 @@ void __init sev_hardware_setup(void) if (!sev_es_enabled || !cpu_feature_enabled(X86_FEATURE_DEBUG_SWAP) || !cpu_feature_enabled(X86_FEATURE_NO_NESTED_DATA_BP)) sev_es_debug_swap_enabled = false; + sev_snp_enabled = sev_snp_supported; #endif } diff --git a/arch/x86/kvm/svm/svm.h b/arch/x86/kvm/svm/svm.h index b7b8bf73cbb9..635430fa641b 100644 --- a/arch/x86/kvm/svm/svm.h +++ b/arch/x86/kvm/svm/svm.h @@ -79,6 +79,7 @@ enum { struct kvm_sev_info { bool active; /* SEV enabled guest */ bool es_active; /* SEV-ES enabled guest */ + bool snp_active; /* SEV-SNP enabled guest */ unsigned int asid; /* ASID used for this guest */ unsigned int handle; /* SEV firmware handle */ int fd; /* SEV device fd */ @@ -339,6 +340,13 @@ static __always_inline bool sev_es_guest(struct kvm *kvm) #endif } +static __always_inline bool sev_snp_guest(struct kvm *kvm) +{ + struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; + + return sev_es_guest(kvm) && sev->snp_active; +} + static inline void vmcb_mark_all_dirty(struct vmcb *vmcb) { vmcb->control.clean = 0;