From f2bc14b69c38b60f201fdf90c08cb2dc8966f331 Mon Sep 17 00:00:00 2001 From: Vitaly Kuznetsov Date: Tue, 26 Jan 2021 14:48:12 +0100 Subject: [PATCH] KVM: x86: hyper-v: Prepare to meet unallocated Hyper-V context Currently, Hyper-V context is part of 'struct kvm_vcpu_arch' and is always available. As a preparation to allocating it dynamically, check that it is not NULL at call sites which can normally proceed without it i.e. the behavior is identical to the situation when Hyper-V emulation is not being used by the guest. When Hyper-V context for a particular vCPU is not allocated, we may still need to get 'vp_index' from there. E.g. in a hypothetical situation when Hyper-V emulation was enabled on one CPU and wasn't on another, Hyper-V style send-IPI hypercall may still be used. Luckily, vp_index is always initialized to kvm_vcpu_get_idx() and can only be changed when Hyper-V context is present. Introduce kvm_hv_get_vpindex() helper for simplification. No functional change intended. Signed-off-by: Vitaly Kuznetsov Message-Id: <20210126134816.1880136-12-vkuznets@redhat.com> Signed-off-by: Paolo Bonzini --- arch/x86/kvm/hyperv.c | 17 ++++++++++------- arch/x86/kvm/hyperv.h | 10 ++++++++++ arch/x86/kvm/lapic.c | 5 +++-- arch/x86/kvm/vmx/vmx.c | 4 +--- arch/x86/kvm/x86.c | 7 +++++-- 5 files changed, 29 insertions(+), 14 deletions(-) diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c index 1482cad..10e7ed2 100644 --- a/arch/x86/kvm/hyperv.c +++ b/arch/x86/kvm/hyperv.c @@ -142,10 +142,10 @@ static struct kvm_vcpu *get_vcpu_by_vpidx(struct kvm *kvm, u32 vpidx) return NULL; vcpu = kvm_get_vcpu(kvm, vpidx); - if (vcpu && to_hv_vcpu(vcpu)->vp_index == vpidx) + if (vcpu && kvm_hv_get_vpindex(vcpu) == vpidx) return vcpu; kvm_for_each_vcpu(i, vcpu, kvm) - if (to_hv_vcpu(vcpu)->vp_index == vpidx) + if (kvm_hv_get_vpindex(vcpu) == vpidx) return vcpu; return NULL; } @@ -377,9 +377,7 @@ static int syndbg_get_msr(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata, bool host) break; } - trace_kvm_hv_syndbg_get_msr(vcpu->vcpu_id, - to_hv_vcpu(vcpu)->vp_index, msr, - *pdata); + trace_kvm_hv_syndbg_get_msr(vcpu->vcpu_id, kvm_hv_get_vpindex(vcpu), msr, *pdata); return 0; } @@ -806,6 +804,9 @@ void kvm_hv_process_stimers(struct kvm_vcpu *vcpu) u64 time_now, exp_time; int i; + if (!hv_vcpu) + return; + for (i = 0; i < ARRAY_SIZE(hv_vcpu->stimer); i++) if (test_and_clear_bit(i, hv_vcpu->stimer_pending_bitmap)) { stimer = &hv_vcpu->stimer[i]; @@ -842,6 +843,9 @@ bool kvm_hv_assist_page_enabled(struct kvm_vcpu *vcpu) { struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu); + if (!hv_vcpu) + return false; + if (!(hv_vcpu->hv_vapic & HV_X64_MSR_VP_ASSIST_PAGE_ENABLE)) return false; return vcpu->arch.pv_eoi.msr_val & KVM_MSR_ENABLED; @@ -1504,8 +1508,7 @@ static __always_inline unsigned long *sparse_set_to_vcpu_mask( bitmap_zero(vcpu_bitmap, KVM_MAX_VCPUS); kvm_for_each_vcpu(i, vcpu, kvm) { - if (test_bit(to_hv_vcpu(vcpu)->vp_index, - (unsigned long *)vp_bitmap)) + if (test_bit(kvm_hv_get_vpindex(vcpu), (unsigned long *)vp_bitmap)) __set_bit(i, vcpu_bitmap); } return vcpu_bitmap; diff --git a/arch/x86/kvm/hyperv.h b/arch/x86/kvm/hyperv.h index be1e3f5..57e53a8 100644 --- a/arch/x86/kvm/hyperv.h +++ b/arch/x86/kvm/hyperv.h @@ -83,6 +83,13 @@ static inline struct kvm_hv_syndbg *to_hv_syndbg(struct kvm_vcpu *vcpu) return &vcpu->kvm->arch.hyperv.hv_syndbg; } +static inline u32 kvm_hv_get_vpindex(struct kvm_vcpu *vcpu) +{ + struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu); + + return hv_vcpu ? hv_vcpu->vp_index : kvm_vcpu_get_idx(vcpu); +} + int kvm_hv_set_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 data, bool host); int kvm_hv_get_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata, bool host); @@ -121,6 +128,9 @@ static inline bool kvm_hv_has_stimer_pending(struct kvm_vcpu *vcpu) { struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu); + if (!hv_vcpu) + return false; + return !bitmap_empty(hv_vcpu->stimer_pending_bitmap, HV_SYNIC_STIMER_COUNT); } diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c index 847fe11..45d40bf 100644 --- a/arch/x86/kvm/lapic.c +++ b/arch/x86/kvm/lapic.c @@ -1245,7 +1245,8 @@ static int apic_set_eoi(struct kvm_lapic *apic) apic_clear_isr(vector, apic); apic_update_ppr(apic); - if (test_bit(vector, to_hv_synic(apic->vcpu)->vec_bitmap)) + if (to_hv_vcpu(apic->vcpu) && + test_bit(vector, to_hv_synic(apic->vcpu)->vec_bitmap)) kvm_hv_synic_send_eoi(apic->vcpu, vector); kvm_ioapic_send_eoi(apic, vector); @@ -2512,7 +2513,7 @@ int kvm_get_apic_interrupt(struct kvm_vcpu *vcpu) */ apic_clear_irr(vector, apic); - if (test_bit(vector, to_hv_synic(vcpu)->auto_eoi_bitmap)) { + if (to_hv_vcpu(vcpu) && test_bit(vector, to_hv_synic(vcpu)->auto_eoi_bitmap)) { /* * For auto-EOI interrupts, there might be another pending * interrupt above PPR, so check whether to raise another diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index f83199f..e0a3a9b 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -6810,12 +6810,10 @@ static fastpath_t vmx_vcpu_run(struct kvm_vcpu *vcpu) /* All fields are clean at this point */ if (static_branch_unlikely(&enable_evmcs)) { - struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu); - current_evmcs->hv_clean_fields |= HV_VMX_ENLIGHTENED_CLEAN_FIELD_ALL; - current_evmcs->hv_vp_id = hv_vcpu->vp_index; + current_evmcs->hv_vp_id = kvm_hv_get_vpindex(vcpu); } /* MSR_IA32_DEBUGCTLMSR is zeroed on vmexit. Restore it if needed */ diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 40bd2e3..7caf95d 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -8803,8 +8803,11 @@ static void vcpu_load_eoi_exitmap(struct kvm_vcpu *vcpu) if (!kvm_apic_hw_enabled(vcpu->arch.apic)) return; - bitmap_or((ulong *)eoi_exit_bitmap, vcpu->arch.ioapic_handled_vectors, - to_hv_synic(vcpu)->vec_bitmap, 256); + if (to_hv_vcpu(vcpu)) + bitmap_or((ulong *)eoi_exit_bitmap, + vcpu->arch.ioapic_handled_vectors, + to_hv_synic(vcpu)->vec_bitmap, 256); + static_call(kvm_x86_load_eoi_exitmap)(vcpu, eoi_exit_bitmap); } -- 2.7.4