diff --git a/arch/x86/kvm/svm/avic.c b/arch/x86/kvm/svm/avic.c index eb979695e7d87..2c6737f72bd43 100644 --- a/arch/x86/kvm/svm/avic.c +++ b/arch/x86/kvm/svm/avic.c @@ -327,6 +327,50 @@ static void avic_kick_vcpu(struct kvm_vcpu *vcpu, u32 icrl) icrl & APIC_VECTOR_MASK); } +static void avic_kick_vcpu_by_physical_id(struct kvm *kvm, u32 physical_id, + u32 icrl) +{ + /* + * KVM inhibits AVIC if any vCPU ID diverges from the vCPUs APIC ID, + * i.e. APIC ID == vCPU ID. + */ + struct kvm_vcpu *target_vcpu = kvm_get_vcpu_by_id(kvm, physical_id); + + /* Once again, nothing to do if the target vCPU doesn't exist. */ + if (unlikely(!target_vcpu)) + return; + + avic_kick_vcpu(target_vcpu, icrl); +} + +static void avic_kick_vcpu_by_logical_id(struct kvm *kvm, u32 *avic_logical_id_table, + u32 logid_index, u32 icrl) +{ + u32 physical_id; + + if (avic_logical_id_table) { + u32 logid_entry = avic_logical_id_table[logid_index]; + + /* Nothing to do if the logical destination is invalid. */ + if (unlikely(!(logid_entry & AVIC_LOGICAL_ID_ENTRY_VALID_MASK))) + return; + + physical_id = logid_entry & + AVIC_LOGICAL_ID_ENTRY_GUEST_PHYSICAL_ID_MASK; + } else { + /* + * For x2APIC, the logical APIC ID is a read-only value that is + * derived from the x2APIC ID, thus the x2APIC ID can be found + * by reversing the calculation (stored in logid_index). Note, + * bits 31:20 of the x2APIC ID aren't propagated to the logical + * ID, but KVM limits the x2APIC ID limited to KVM_MAX_VCPU_IDS. + */ + physical_id = logid_index; + } + + avic_kick_vcpu_by_physical_id(kvm, physical_id, icrl); +} + /* * A fast-path version of avic_kick_target_vcpus(), which attempts to match * destination APIC ID to vCPU without looping through all vCPUs. @@ -334,11 +378,10 @@ static void avic_kick_vcpu(struct kvm_vcpu *vcpu, u32 icrl) static int avic_kick_target_vcpus_fast(struct kvm *kvm, struct kvm_lapic *source, u32 icrl, u32 icrh, u32 index) { - u32 l1_physical_id, dest; - struct kvm_vcpu *target_vcpu; int dest_mode = icrl & APIC_DEST_MASK; int shorthand = icrl & APIC_SHORT_MASK; struct kvm_svm *kvm_svm = to_kvm_svm(kvm); + u32 dest; if (shorthand != APIC_DEST_NOSHORT) return -EINVAL; @@ -355,14 +398,14 @@ static int avic_kick_target_vcpus_fast(struct kvm *kvm, struct kvm_lapic *source if (!apic_x2apic_mode(source) && dest == APIC_BROADCAST) return -EINVAL; - l1_physical_id = dest; - - if (WARN_ON_ONCE(l1_physical_id != index)) + if (WARN_ON_ONCE(dest != index)) return -EINVAL; + avic_kick_vcpu_by_physical_id(kvm, dest, icrl); } else { - u32 bitmap, cluster; - int logid_index; + u32 *avic_logical_id_table; + unsigned long bitmap, i; + u32 cluster; if (apic_x2apic_mode(source)) { /* 16 bit dest mask, 16 bit cluster id */ @@ -382,50 +425,21 @@ static int avic_kick_target_vcpus_fast(struct kvm *kvm, struct kvm_lapic *source if (unlikely(!bitmap)) return 0; - if (!is_power_of_2(bitmap)) - /* multiple logical destinations, use slow path */ - return -EINVAL; - - logid_index = cluster + __ffs(bitmap); - - if (apic_x2apic_mode(source)) { - /* - * For x2APIC, the logical APIC ID is a read-only value - * that is derived from the x2APIC ID, thus the x2APIC - * ID can be found by reversing the calculation (done - * above). Note, bits 31:20 of the x2APIC ID are not - * propagated to the logical ID, but KVM limits the - * x2APIC ID limited to KVM_MAX_VCPU_IDS. - */ - l1_physical_id = logid_index; - } else { - u32 *avic_logical_id_table = - page_address(kvm_svm->avic_logical_id_table_page); - - u32 logid_entry = avic_logical_id_table[logid_index]; - - if (WARN_ON_ONCE(index != logid_index)) - return -EINVAL; - - /* Nothing to do if the logical destination is invalid. */ - if (unlikely(!(logid_entry & AVIC_LOGICAL_ID_ENTRY_VALID_MASK))) - return 0; + if (apic_x2apic_mode(source)) + avic_logical_id_table = NULL; + else + avic_logical_id_table = page_address(kvm_svm->avic_logical_id_table_page); - l1_physical_id = logid_entry & - AVIC_LOGICAL_ID_ENTRY_GUEST_PHYSICAL_ID_MASK; - } + /* + * AVIC is inhibited if vCPUs aren't mapped 1:1 with logical + * IDs, thus each bit in the destination is guaranteed to map + * to at most one vCPU. + */ + for_each_set_bit(i, &bitmap, 16) + avic_kick_vcpu_by_logical_id(kvm, avic_logical_id_table, + cluster + i, icrl); } - /* - * KVM inhibits AVIC if any vCPU ID diverges from the vCPUs APIC ID, - * i.e. APIC ID == vCPU ID. Once again, nothing to do if the target - * vCPU doesn't exist. - */ - target_vcpu = kvm_get_vcpu_by_id(kvm, l1_physical_id); - if (unlikely(!target_vcpu)) - return 0; - - avic_kick_vcpu(target_vcpu, icrl); return 0; }