diff options
author | Suravee Suthikulpanit <suravee.suthikulpanit@amd.com> | 2022-05-19 05:26:55 -0500 |
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committer | Paolo Bonzini <pbonzini@redhat.com> | 2022-06-24 12:44:54 -0400 |
commit | 4bdec12aa8d6d0fd7f1ac6740c456bf726e53c0b (patch) | |
tree | 575b704109e9b67a85d2251c58ee2b75527264fb /arch/x86/kvm/svm/avic.c | |
parent | bf348f667ed36c0799dd6d10adb7be9cdfea48c3 (diff) | |
download | linux-4bdec12aa8d6d0fd7f1ac6740c456bf726e53c0b.tar.gz |
KVM: SVM: Detect X2APIC virtualization (x2AVIC) support
Add CPUID check for the x2APIC virtualization (x2AVIC) feature.
If available, the SVM driver can support both AVIC and x2AVIC modes
when load the kvm_amd driver with avic=1. The operating mode will be
determined at runtime depending on the guest APIC mode.
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Reviewed-by: Pankaj Gupta <pankaj.gupta@amd.com>
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Message-Id: <20220519102709.24125-4-suravee.suthikulpanit@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch/x86/kvm/svm/avic.c')
-rw-r--r-- | arch/x86/kvm/svm/avic.c | 45 |
1 files changed, 45 insertions, 0 deletions
diff --git a/arch/x86/kvm/svm/avic.c b/arch/x86/kvm/svm/avic.c index 37016feb5ac4..509163833cbc 100644 --- a/arch/x86/kvm/svm/avic.c +++ b/arch/x86/kvm/svm/avic.c @@ -40,6 +40,9 @@ #define AVIC_GATAG_TO_VMID(x) ((x >> AVIC_VCPU_ID_BITS) & AVIC_VM_ID_MASK) #define AVIC_GATAG_TO_VCPUID(x) (x & AVIC_VCPU_ID_MASK) +static bool force_avic; +module_param_unsafe(force_avic, bool, 0444); + /* Note: * This hash table is used to map VM_ID to a struct kvm_svm, * when handling AMD IOMMU GALOG notification to schedule in @@ -50,6 +53,7 @@ static DEFINE_HASHTABLE(svm_vm_data_hash, SVM_VM_DATA_HASH_BITS); static u32 next_vm_id = 0; static bool next_vm_id_wrapped = 0; static DEFINE_SPINLOCK(svm_vm_data_hash_lock); +enum avic_modes avic_mode; /* * This is a wrapper of struct amd_iommu_ir_data. @@ -1058,3 +1062,44 @@ void avic_vcpu_unblocking(struct kvm_vcpu *vcpu) avic_vcpu_load(vcpu, vcpu->cpu); } + +/* + * Note: + * - The module param avic enable both xAPIC and x2APIC mode. + * - Hypervisor can support both xAVIC and x2AVIC in the same guest. + * - The mode can be switched at run-time. + */ +bool avic_hardware_setup(struct kvm_x86_ops *x86_ops) +{ + if (!npt_enabled) + return false; + + if (boot_cpu_has(X86_FEATURE_AVIC)) { + avic_mode = AVIC_MODE_X1; + pr_info("AVIC enabled\n"); + } else if (force_avic) { + /* + * Some older systems does not advertise AVIC support. + * See Revision Guide for specific AMD processor for more detail. + */ + avic_mode = AVIC_MODE_X1; + pr_warn("AVIC is not supported in CPUID but force enabled"); + pr_warn("Your system might crash and burn"); + } + + /* AVIC is a prerequisite for x2AVIC. */ + if (boot_cpu_has(X86_FEATURE_X2AVIC)) { + if (avic_mode == AVIC_MODE_X1) { + avic_mode = AVIC_MODE_X2; + pr_info("x2AVIC enabled\n"); + } else { + pr_warn(FW_BUG "Cannot support x2AVIC due to AVIC is disabled"); + pr_warn(FW_BUG "Try enable AVIC using force_avic option"); + } + } + + if (avic_mode != AVIC_MODE_NONE) + amd_iommu_register_ga_log_notifier(&avic_ga_log_notifier); + + return !!avic_mode; +} |