diff options
Diffstat (limited to 'arch/x86/kvm')
| -rw-r--r-- | arch/x86/kvm/hyperv.c | 91 | ||||
| -rw-r--r-- | arch/x86/kvm/hyperv.h | 1 | ||||
| -rw-r--r-- | arch/x86/kvm/lapic.c | 12 | ||||
| -rw-r--r-- | arch/x86/kvm/mmu/mmu_internal.h | 5 | ||||
| -rw-r--r-- | arch/x86/kvm/mmu/tdp_iter.c | 30 | ||||
| -rw-r--r-- | arch/x86/kvm/mmu/tdp_iter.h | 4 | ||||
| -rw-r--r-- | arch/x86/kvm/mmu/tdp_mmu.c | 51 | ||||
| -rw-r--r-- | arch/x86/kvm/svm/svm.c | 25 | ||||
| -rw-r--r-- | arch/x86/kvm/vmx/vmx.c | 2 | ||||
| -rw-r--r-- | arch/x86/kvm/x86.c | 115 |
10 files changed, 228 insertions, 108 deletions
diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c index 58fa8c029867..f98370a39936 100644 --- a/arch/x86/kvm/hyperv.c +++ b/arch/x86/kvm/hyperv.c @@ -520,10 +520,10 @@ static u64 get_time_ref_counter(struct kvm *kvm) u64 tsc; /* - * The guest has not set up the TSC page or the clock isn't - * stable, fall back to get_kvmclock_ns. + * Fall back to get_kvmclock_ns() when TSC page hasn't been set up, + * is broken, disabled or being updated. */ - if (!hv->tsc_ref.tsc_sequence) + if (hv->hv_tsc_page_status != HV_TSC_PAGE_SET) return div_u64(get_kvmclock_ns(kvm), 100); vcpu = kvm_get_vcpu(kvm, 0); @@ -1077,6 +1077,21 @@ static bool compute_tsc_page_parameters(struct pvclock_vcpu_time_info *hv_clock, return true; } +/* + * Don't touch TSC page values if the guest has opted for TSC emulation after + * migration. KVM doesn't fully support reenlightenment notifications and TSC + * access emulation and Hyper-V is known to expect the values in TSC page to + * stay constant before TSC access emulation is disabled from guest side + * (HV_X64_MSR_TSC_EMULATION_STATUS). KVM userspace is expected to preserve TSC + * frequency and guest visible TSC value across migration (and prevent it when + * TSC scaling is unsupported). + */ +static inline bool tsc_page_update_unsafe(struct kvm_hv *hv) +{ + return (hv->hv_tsc_page_status != HV_TSC_PAGE_GUEST_CHANGED) && + hv->hv_tsc_emulation_control; +} + void kvm_hv_setup_tsc_page(struct kvm *kvm, struct pvclock_vcpu_time_info *hv_clock) { @@ -1087,7 +1102,8 @@ void kvm_hv_setup_tsc_page(struct kvm *kvm, BUILD_BUG_ON(sizeof(tsc_seq) != sizeof(hv->tsc_ref.tsc_sequence)); BUILD_BUG_ON(offsetof(struct ms_hyperv_tsc_page, tsc_sequence) != 0); - if (!(hv->hv_tsc_page & HV_X64_MSR_TSC_REFERENCE_ENABLE)) + if (hv->hv_tsc_page_status == HV_TSC_PAGE_BROKEN || + hv->hv_tsc_page_status == HV_TSC_PAGE_UNSET) return; mutex_lock(&hv->hv_lock); @@ -1101,7 +1117,15 @@ void kvm_hv_setup_tsc_page(struct kvm *kvm, */ if (unlikely(kvm_read_guest(kvm, gfn_to_gpa(gfn), &tsc_seq, sizeof(tsc_seq)))) + goto out_err; + + if (tsc_seq && tsc_page_update_unsafe(hv)) { + if (kvm_read_guest(kvm, gfn_to_gpa(gfn), &hv->tsc_ref, sizeof(hv->tsc_ref))) + goto out_err; + + hv->hv_tsc_page_status = HV_TSC_PAGE_SET; goto out_unlock; + } /* * While we're computing and writing the parameters, force the @@ -1110,15 +1134,15 @@ void kvm_hv_setup_tsc_page(struct kvm *kvm, hv->tsc_ref.tsc_sequence = 0; if (kvm_write_guest(kvm, gfn_to_gpa(gfn), &hv->tsc_ref, sizeof(hv->tsc_ref.tsc_sequence))) - goto out_unlock; + goto out_err; if (!compute_tsc_page_parameters(hv_clock, &hv->tsc_ref)) - goto out_unlock; + goto out_err; /* Ensure sequence is zero before writing the rest of the struct. */ smp_wmb(); if (kvm_write_guest(kvm, gfn_to_gpa(gfn), &hv->tsc_ref, sizeof(hv->tsc_ref))) - goto out_unlock; + goto out_err; /* * Now switch to the TSC page mechanism by writing the sequence. @@ -1131,8 +1155,45 @@ void kvm_hv_setup_tsc_page(struct kvm *kvm, smp_wmb(); hv->tsc_ref.tsc_sequence = tsc_seq; - kvm_write_guest(kvm, gfn_to_gpa(gfn), - &hv->tsc_ref, sizeof(hv->tsc_ref.tsc_sequence)); + if (kvm_write_guest(kvm, gfn_to_gpa(gfn), + &hv->tsc_ref, sizeof(hv->tsc_ref.tsc_sequence))) + goto out_err; + + hv->hv_tsc_page_status = HV_TSC_PAGE_SET; + goto out_unlock; + +out_err: + hv->hv_tsc_page_status = HV_TSC_PAGE_BROKEN; +out_unlock: + mutex_unlock(&hv->hv_lock); +} + +void kvm_hv_invalidate_tsc_page(struct kvm *kvm) +{ + struct kvm_hv *hv = to_kvm_hv(kvm); + u64 gfn; + + if (hv->hv_tsc_page_status == HV_TSC_PAGE_BROKEN || + hv->hv_tsc_page_status == HV_TSC_PAGE_UNSET || + tsc_page_update_unsafe(hv)) + return; + + mutex_lock(&hv->hv_lock); + + if (!(hv->hv_tsc_page & HV_X64_MSR_TSC_REFERENCE_ENABLE)) + goto out_unlock; + + /* Preserve HV_TSC_PAGE_GUEST_CHANGED/HV_TSC_PAGE_HOST_CHANGED states */ + if (hv->hv_tsc_page_status == HV_TSC_PAGE_SET) + hv->hv_tsc_page_status = HV_TSC_PAGE_UPDATING; + + gfn = hv->hv_tsc_page >> HV_X64_MSR_TSC_REFERENCE_ADDRESS_SHIFT; + + hv->tsc_ref.tsc_sequence = 0; + if (kvm_write_guest(kvm, gfn_to_gpa(gfn), + &hv->tsc_ref, sizeof(hv->tsc_ref.tsc_sequence))) + hv->hv_tsc_page_status = HV_TSC_PAGE_BROKEN; + out_unlock: mutex_unlock(&hv->hv_lock); } @@ -1193,8 +1254,15 @@ static int kvm_hv_set_msr_pw(struct kvm_vcpu *vcpu, u32 msr, u64 data, } case HV_X64_MSR_REFERENCE_TSC: hv->hv_tsc_page = data; - if (hv->hv_tsc_page & HV_X64_MSR_TSC_REFERENCE_ENABLE) + if (hv->hv_tsc_page & HV_X64_MSR_TSC_REFERENCE_ENABLE) { + if (!host) + hv->hv_tsc_page_status = HV_TSC_PAGE_GUEST_CHANGED; + else + hv->hv_tsc_page_status = HV_TSC_PAGE_HOST_CHANGED; kvm_make_request(KVM_REQ_MASTERCLOCK_UPDATE, vcpu); + } else { + hv->hv_tsc_page_status = HV_TSC_PAGE_UNSET; + } break; case HV_X64_MSR_CRASH_P0 ... HV_X64_MSR_CRASH_P4: return kvm_hv_msr_set_crash_data(kvm, @@ -1229,6 +1297,9 @@ static int kvm_hv_set_msr_pw(struct kvm_vcpu *vcpu, u32 msr, u64 data, hv->hv_tsc_emulation_control = data; break; case HV_X64_MSR_TSC_EMULATION_STATUS: + if (data && !host) + return 1; + hv->hv_tsc_emulation_status = data; break; case HV_X64_MSR_TIME_REF_COUNT: diff --git a/arch/x86/kvm/hyperv.h b/arch/x86/kvm/hyperv.h index e951af1fcb2c..60547d5cb6d7 100644 --- a/arch/x86/kvm/hyperv.h +++ b/arch/x86/kvm/hyperv.h @@ -133,6 +133,7 @@ void kvm_hv_process_stimers(struct kvm_vcpu *vcpu); void kvm_hv_setup_tsc_page(struct kvm *kvm, struct pvclock_vcpu_time_info *hv_clock); +void kvm_hv_invalidate_tsc_page(struct kvm *kvm); void kvm_hv_init_vm(struct kvm *kvm); void kvm_hv_destroy_vm(struct kvm *kvm); diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c index 45d40bfacb7c..cc369b9ad8f1 100644 --- a/arch/x86/kvm/lapic.c +++ b/arch/x86/kvm/lapic.c @@ -1642,7 +1642,16 @@ static void apic_timer_expired(struct kvm_lapic *apic, bool from_timer_fn) } if (kvm_use_posted_timer_interrupt(apic->vcpu)) { - kvm_wait_lapic_expire(vcpu); + /* + * Ensure the guest's timer has truly expired before posting an + * interrupt. Open code the relevant checks to avoid querying + * lapic_timer_int_injected(), which will be false since the + * interrupt isn't yet injected. Waiting until after injecting + * is not an option since that won't help a posted interrupt. + */ + if (vcpu->arch.apic->lapic_timer.expired_tscdeadline && + vcpu->arch.apic->lapic_timer.timer_advance_ns) + __kvm_wait_lapic_expire(vcpu); kvm_apic_inject_pending_timer_irqs(apic); return; } @@ -2595,6 +2604,7 @@ int kvm_apic_set_state(struct kvm_vcpu *vcpu, struct kvm_lapic_state *s) apic_update_ppr(apic); hrtimer_cancel(&apic->lapic_timer.timer); + apic->lapic_timer.expired_tscdeadline = 0; apic_update_lvtt(apic); apic_manage_nmi_watchdog(apic, kvm_lapic_get_reg(apic, APIC_LVT0)); update_divide_count(apic); diff --git a/arch/x86/kvm/mmu/mmu_internal.h b/arch/x86/kvm/mmu/mmu_internal.h index ec4fc28b325a..1f6f98c76bdf 100644 --- a/arch/x86/kvm/mmu/mmu_internal.h +++ b/arch/x86/kvm/mmu/mmu_internal.h @@ -78,6 +78,11 @@ static inline struct kvm_mmu_page *sptep_to_sp(u64 *sptep) return to_shadow_page(__pa(sptep)); } +static inline int kvm_mmu_page_as_id(struct kvm_mmu_page *sp) +{ + return sp->role.smm ? 1 : 0; +} + static inline bool kvm_vcpu_ad_need_write_protect(struct kvm_vcpu *vcpu) { /* diff --git a/arch/x86/kvm/mmu/tdp_iter.c b/arch/x86/kvm/mmu/tdp_iter.c index e5f148106e20..b3ed302c1a35 100644 --- a/arch/x86/kvm/mmu/tdp_iter.c +++ b/arch/x86/kvm/mmu/tdp_iter.c @@ -21,6 +21,21 @@ static gfn_t round_gfn_for_level(gfn_t gfn, int level) } /* + * Return the TDP iterator to the root PT and allow it to continue its + * traversal over the paging structure from there. + */ +void tdp_iter_restart(struct tdp_iter *iter) +{ + iter->yielded_gfn = iter->next_last_level_gfn; + iter->level = iter->root_level; + + iter->gfn = round_gfn_for_level(iter->next_last_level_gfn, iter->level); + tdp_iter_refresh_sptep(iter); + + iter->valid = true; +} + +/* * Sets a TDP iterator to walk a pre-order traversal of the paging structure * rooted at root_pt, starting with the walk to translate next_last_level_gfn. */ @@ -31,16 +46,12 @@ void tdp_iter_start(struct tdp_iter *iter, u64 *root_pt, int root_level, WARN_ON(root_level > PT64_ROOT_MAX_LEVEL); iter->next_last_level_gfn = next_last_level_gfn; - iter->yielded_gfn = iter->next_last_level_gfn; iter->root_level = root_level; iter->min_level = min_level; - iter->level = root_level; - iter->pt_path[iter->level - 1] = (tdp_ptep_t)root_pt; - - iter->gfn = round_gfn_for_level(iter->next_last_level_gfn, iter->level); - tdp_iter_refresh_sptep(iter); + iter->pt_path[iter->root_level - 1] = (tdp_ptep_t)root_pt; + iter->as_id = kvm_mmu_page_as_id(sptep_to_sp(root_pt)); - iter->valid = true; + tdp_iter_restart(iter); } /* @@ -159,8 +170,3 @@ void tdp_iter_next(struct tdp_iter *iter) iter->valid = false; } -tdp_ptep_t tdp_iter_root_pt(struct tdp_iter *iter) -{ - return iter->pt_path[iter->root_level - 1]; -} - diff --git a/arch/x86/kvm/mmu/tdp_iter.h b/arch/x86/kvm/mmu/tdp_iter.h index 4cc177d75c4a..b1748b988d3a 100644 --- a/arch/x86/kvm/mmu/tdp_iter.h +++ b/arch/x86/kvm/mmu/tdp_iter.h @@ -36,6 +36,8 @@ struct tdp_iter { int min_level; /* The iterator's current level within the paging structure */ int level; + /* The address space ID, i.e. SMM vs. regular. */ + int as_id; /* A snapshot of the value at sptep */ u64 old_spte; /* @@ -62,6 +64,6 @@ tdp_ptep_t spte_to_child_pt(u64 pte, int level); void tdp_iter_start(struct tdp_iter *iter, u64 *root_pt, int root_level, int min_level, gfn_t next_last_level_gfn); void tdp_iter_next(struct tdp_iter *iter); -tdp_ptep_t tdp_iter_root_pt(struct tdp_iter *iter); +void tdp_iter_restart(struct tdp_iter *iter); #endif /* __KVM_X86_MMU_TDP_ITER_H */ diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c index c926c6b899a1..462b1f71c77f 100644 --- a/arch/x86/kvm/mmu/tdp_mmu.c +++ b/arch/x86/kvm/mmu/tdp_mmu.c @@ -203,11 +203,6 @@ static void handle_changed_spte(struct kvm *kvm, int as_id, gfn_t gfn, u64 old_spte, u64 new_spte, int level, bool shared); -static int kvm_mmu_page_as_id(struct kvm_mmu_page *sp) -{ - return sp->role.smm ? 1 : 0; -} - static void handle_changed_spte_acc_track(u64 old_spte, u64 new_spte, int level) { bool pfn_changed = spte_to_pfn(old_spte) != spte_to_pfn(new_spte); @@ -301,11 +296,16 @@ static void tdp_mmu_unlink_page(struct kvm *kvm, struct kvm_mmu_page *sp, * * Given a page table that has been removed from the TDP paging structure, * iterates through the page table to clear SPTEs and free child page tables. + * + * Note that pt is passed in as a tdp_ptep_t, but it does not need RCU + * protection. Since this thread removed it from the paging structure, + * this thread will be responsible for ensuring the page is freed. Hence the + * early rcu_dereferences in the function. */ -static void handle_removed_tdp_mmu_page(struct kvm *kvm, u64 *pt, +static void handle_removed_tdp_mmu_page(struct kvm *kvm, tdp_ptep_t pt, bool shared) { - struct kvm_mmu_page *sp = sptep_to_sp(pt); + struct kvm_mmu_page *sp = sptep_to_sp(rcu_dereference(pt)); int level = sp->role.level; gfn_t base_gfn = sp->gfn; u64 old_child_spte; @@ -318,7 +318,7 @@ static void handle_removed_tdp_mmu_page(struct kvm *kvm, u64 *pt, tdp_mmu_unlink_page(kvm, sp, shared); for (i = 0; i < PT64_ENT_PER_PAGE; i++) { - sptep = pt + i; + sptep = rcu_dereference(pt) + i; gfn = base_gfn + (i * KVM_PAGES_PER_HPAGE(level - 1)); if (shared) { @@ -337,7 +337,18 @@ static void handle_removed_tdp_mmu_page(struct kvm *kvm, u64 *pt, cpu_relax(); } } else { + /* + * If the SPTE is not MMU-present, there is no backing + * page associated with the SPTE and so no side effects + * that need to be recorded, and exclusive ownership of + * mmu_lock ensures the SPTE can't be made present. + * Note, zapping MMIO SPTEs is also unnecessary as they + * are guarded by the memslots generation, not by being + * unreachable. + */ old_child_spte = READ_ONCE(*sptep); + if (!is_shadow_present_pte(old_child_spte)) + continue; /* * Marking the SPTE as a removed SPTE is not @@ -481,10 +492,6 @@ static inline bool tdp_mmu_set_spte_atomic(struct kvm *kvm, struct tdp_iter *iter, u64 new_spte) { - u64 *root_pt = tdp_iter_root_pt(iter); - struct kvm_mmu_page *root = sptep_to_sp(root_pt); - int as_id = kvm_mmu_page_as_id(root); - lockdep_assert_held_read(&kvm->mmu_lock); /* @@ -498,8 +505,8 @@ static inline bool tdp_mmu_set_spte_atomic(struct kvm *kvm, new_spte) != iter->old_spte) return false; - handle_changed_spte(kvm, as_id, iter->gfn, iter->old_spte, new_spte, - iter->level, true); + handle_changed_spte(kvm, iter->as_id, iter->gfn, iter->old_spte, + new_spte, iter->level, true); return true; } @@ -527,7 +534,7 @@ static inline bool tdp_mmu_zap_spte_atomic(struct kvm *kvm, * here since the SPTE is going from non-present * to non-present. */ - WRITE_ONCE(*iter->sptep, 0); + WRITE_ONCE(*rcu_dereference(iter->sptep), 0); return true; } @@ -553,10 +560,6 @@ static inline void __tdp_mmu_set_spte(struct kvm *kvm, struct tdp_iter *iter, u64 new_spte, bool record_acc_track, bool record_dirty_log) { - tdp_ptep_t root_pt = tdp_iter_root_pt(iter); - struct kvm_mmu_page *root = sptep_to_sp(root_pt); - int as_id = kvm_mmu_page_as_id(root); - lockdep_assert_held_write(&kvm->mmu_lock); /* @@ -570,13 +573,13 @@ static inline void __tdp_mmu_set_spte(struct kvm *kvm, struct tdp_iter *iter, WRITE_ONCE(*rcu_dereference(iter->sptep), new_spte); - __handle_changed_spte(kvm, as_id, iter->gfn, iter->old_spte, new_spte, - iter->level, false); + __handle_changed_spte(kvm, iter->as_id, iter->gfn, iter->old_spte, + new_spte, iter->level, false); if (record_acc_track) handle_changed_spte_acc_track(iter->old_spte, new_spte, iter->level); if (record_dirty_log) - handle_changed_spte_dirty_log(kvm, as_id, iter->gfn, + handle_changed_spte_dirty_log(kvm, iter->as_id, iter->gfn, iter->old_spte, new_spte, iter->level); } @@ -648,9 +651,7 @@ static inline bool tdp_mmu_iter_cond_resched(struct kvm *kvm, WARN_ON(iter->gfn > iter->next_last_level_gfn); - tdp_iter_start(iter, iter->pt_path[iter->root_level - 1], - iter->root_level, iter->min_level, - iter->next_last_level_gfn); + tdp_iter_restart(iter); return true; } diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c index baee91c1e936..58a45bb139f8 100644 --- a/arch/x86/kvm/svm/svm.c +++ b/arch/x86/kvm/svm/svm.c @@ -115,13 +115,6 @@ static const struct svm_direct_access_msrs { { .index = MSR_INVALID, .always = false }, }; -/* enable NPT for AMD64 and X86 with PAE */ -#if defined(CONFIG_X86_64) || defined(CONFIG_X86_PAE) -bool npt_enabled = true; -#else -bool npt_enabled; -#endif - /* * These 2 parameters are used to config the controls for Pause-Loop Exiting: * pause_filter_count: On processors that support Pause filtering(indicated @@ -170,9 +163,12 @@ module_param(pause_filter_count_shrink, ushort, 0444); static unsigned short pause_filter_count_max = KVM_SVM_DEFAULT_PLE_WINDOW_MAX; module_param(pause_filter_count_max, ushort, 0444); -/* allow nested paging (virtualized MMU) for all guests */ -static int npt = true; -module_param(npt, int, S_IRUGO); +/* + * Use nested page tables by default. Note, NPT may get forced off by + * svm_hardware_setup() if it's unsupported by hardware or the host kernel. + */ +bool npt_enabled = true; +module_param_named(npt, npt_enabled, bool, 0444); /* allow nested virtualization in KVM/SVM */ static int nested = true; @@ -988,10 +984,15 @@ static __init int svm_hardware_setup(void) goto err; } - if (!boot_cpu_has(X86_FEATURE_NPT)) + /* + * KVM's MMU doesn't support using 2-level paging for itself, and thus + * NPT isn't supported if the host is using 2-level paging since host + * CR4 is unchanged on VMRUN. + */ + if (!IS_ENABLED(CONFIG_X86_64) && !IS_ENABLED(CONFIG_X86_PAE)) npt_enabled = false; - if (npt_enabled && !npt) + if (!boot_cpu_has(X86_FEATURE_NPT)) npt_enabled = false; kvm_configure_mmu(npt_enabled, get_max_npt_level(), PG_LEVEL_1G); diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index 50810d471462..32cf8287d4a7 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -6580,8 +6580,8 @@ static void atomic_switch_perf_msrs(struct vcpu_vmx *vmx) int i, nr_msrs; struct perf_guest_switch_msr *msrs; + /* Note, nr_msrs may be garbage if perf_guest_get_msrs() returns NULL. */ msrs = perf_guest_get_msrs(&nr_msrs); - if (!msrs) return; diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 2a20ce60152e..fe806e894212 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -1526,35 +1526,44 @@ EXPORT_SYMBOL_GPL(kvm_enable_efer_bits); bool kvm_msr_allowed(struct kvm_vcpu *vcpu, u32 index, u32 type) { + struct kvm_x86_msr_filter *msr_filter; + struct msr_bitmap_range *ranges; struct kvm *kvm = vcpu->kvm; - struct msr_bitmap_range *ranges = kvm->arch.msr_filter.ranges; - u32 count = kvm->arch.msr_filter.count; - u32 i; - bool r = kvm->arch.msr_filter.default_allow; + bool allowed; int idx; + u32 i; - /* MSR filtering not set up or x2APIC enabled, allow everything */ - if (!count || (index >= 0x800 && index <= 0x8ff)) + /* x2APIC MSRs do not support filtering. */ + if (index >= 0x800 && index <= 0x8ff) return true; - /* Prevent collision with set_msr_filter */ idx = srcu_read_lock(&kvm->srcu); - for (i = 0; i < count; i++) { + msr_filter = srcu_dereference(kvm->arch.msr_filter, &kvm->srcu); + if (!msr_filter) { + allowed = true; + goto out; + } + + allowed = msr_filter->default_allow; + ranges = msr_filter->ranges; + + for (i = 0; i < msr_filter->count; i++) { u32 start = ranges[i].base; u32 end = start + ranges[i].nmsrs; u32 flags = ranges[i].flags; unsigned long *bitmap = ranges[i].bitmap; if ((index >= start) && (index < end) && (flags & type)) { - r = !!test_bit(index - start, bitmap); + allowed = !!test_bit(index - start, bitmap); break; } } +out: srcu_read_unlock(&kvm->srcu, idx); - return r; + return allowed; } EXPORT_SYMBOL_GPL(kvm_msr_allowed); @@ -2551,6 +2560,8 @@ static void kvm_gen_update_masterclock(struct kvm *kvm) struct kvm_vcpu *vcpu; struct kvm_arch *ka = &kvm->arch; + kvm_hv_invalidate_tsc_page(kvm); + spin_lock(&ka->pvclock_gtod_sync_lock); kvm_make_mclock_inprogress_request(kvm); /* no guest entries from this point */ @@ -5352,25 +5363,34 @@ split_irqchip_unlock: return r; } -static void kvm_clear_msr_filter(struct kvm *kvm) +static struct kvm_x86_msr_filter *kvm_alloc_msr_filter(bool default_allow) +{ + struct kvm_x86_msr_filter *msr_filter; + + msr_filter = kzalloc(sizeof(*msr_filter), GFP_KERNEL_ACCOUNT); + if (!msr_filter) + return NULL; + + msr_filter->default_allow = default_allow; + return msr_filter; +} + +static void kvm_free_msr_filter(struct kvm_x86_msr_filter *msr_filter) { u32 i; - u32 count = kvm->arch.msr_filter.count; - struct msr_bitmap_range ranges[16]; - mutex_lock(&kvm->lock); - kvm->arch.msr_filter.count = 0; - memcpy(ranges, kvm->arch.msr_filter.ranges, count * sizeof(ranges[0])); - mutex_unlock(&kvm->lock); - synchronize_srcu(&kvm->srcu); + if (!msr_filter) + return; + + for (i = 0; i < msr_filter->count; i++) + kfree(msr_filter->ranges[i].bitmap); - for (i = 0; i < count; i++) - kfree(ranges[i].bitmap); + kfree(msr_filter); } -static int kvm_add_msr_filter(struct kvm *kvm, struct kvm_msr_filter_range *user_range) +static int kvm_add_msr_filter(struct kvm_x86_msr_filter *msr_filter, + struct kvm_msr_filter_range *user_range) { - struct msr_bitmap_range *ranges = kvm->arch.msr_filter.ranges; struct msr_bitmap_range range; unsigned long *bitmap = NULL; size_t bitmap_size; @@ -5404,11 +5424,9 @@ static int kvm_add_msr_filter(struct kvm *kvm, struct kvm_msr_filter_range *user goto err; } - /* Everything ok, add this range identifier to our global pool */ - ranges[kvm->arch.msr_filter.count] = range; - /* Make sure we filled the array before we tell anyone to walk it */ - smp_wmb(); - kvm->arch.msr_filter.count++; + /* Everything ok, add this range identifier. */ + msr_filter->ranges[msr_filter->count] = range; + msr_filter->count++; return 0; err: @@ -5419,10 +5437,11 @@ err: static int kvm_vm_ioctl_set_msr_filter(struct kvm *kvm, void __user *argp) { struct kvm_msr_filter __user *user_msr_filter = argp; + struct kvm_x86_msr_filter *new_filter, *old_filter; struct kvm_msr_filter filter; bool default_allow; - int r = 0; bool empty = true; + int r = 0; u32 i; if (copy_from_user(&filter, user_msr_filter, sizeof(filter))) @@ -5435,25 +5454,32 @@ static int kvm_vm_ioctl_set_msr_filter(struct kvm *kvm, void __user *argp) if (empty && !default_allow) return -EINVAL; - kvm_clear_msr_filter(kvm); - - kvm->arch.msr_filter.default_allow = default_allow; + new_filter = kvm_alloc_msr_filter(default_allow); + if (!new_filter) + return -ENOMEM; - /* - * Protect from concurrent calls to this function that could trigger - * a TOCTOU violation on kvm->arch.msr_filter.count. - */ - mutex_lock(&kvm->lock); for (i = 0; i < ARRAY_SIZE(filter.ranges); i++) { - r = kvm_add_msr_filter(kvm, &filter.ranges[i]); - if (r) - break; + r = kvm_add_msr_filter(new_filter, &filter.ranges[i]); + if (r) { + kvm_free_msr_filter(new_filter); + return r; + } } + mutex_lock(&kvm->lock); + + /* The per-VM filter is protected by kvm->lock... */ + old_filter = srcu_dereference_check(kvm->arch.msr_filter, &kvm->srcu, 1); + + rcu_assign_pointer(kvm->arch.msr_filter, new_filter); + synchronize_srcu(&kvm->srcu); + + kvm_free_msr_filter(old_filter); + kvm_make_all_cpus_request(kvm, KVM_REQ_MSR_FILTER_CHANGED); mutex_unlock(&kvm->lock); - return r; + return 0; } long kvm_arch_vm_ioctl(struct file *filp, @@ -6603,7 +6629,7 @@ static int kvm_emulate_wbinvd_noskip(struct kvm_vcpu *vcpu) int cpu = get_cpu(); cpumask_set_cpu(cpu, vcpu->arch.wbinvd_dirty_mask); - smp_call_function_many(vcpu->arch.wbinvd_dirty_mask, + on_each_cpu_mask(vcpu->arch.wbinvd_dirty_mask, wbinvd_ipi, NULL, 1); put_cpu(); cpumask_clear(vcpu->arch.wbinvd_dirty_mask); @@ -10601,7 +10627,7 @@ void __user * __x86_set_memory_region(struct kvm *kvm, int id, gpa_t gpa, return (void __user *)hva; } else { if (!slot || !slot->npages) - return 0; + return NULL; old_npages = slot->npages; hva = slot->userspace_addr; @@ -10634,8 +10660,6 @@ void kvm_arch_pre_destroy_vm(struct kvm *kvm) void kvm_arch_destroy_vm(struct kvm *kvm) { - u32 i; - if (current->mm == kvm->mm) { /* * Free memory regions allocated on behalf of userspace, @@ -10651,8 +10675,7 @@ void kvm_arch_destroy_vm(struct kvm *kvm) mutex_unlock(&kvm->slots_lock); } static_call_cond(kvm_x86_vm_destroy)(kvm); - for (i = 0; i < kvm->arch.msr_filter.count; i++) - kfree(kvm->arch.msr_filter.ranges[i].bitmap); + kvm_free_msr_filter(srcu_dereference_check(kvm->arch.msr_filter, &kvm->srcu, 1)); kvm_pic_destroy(kvm); kvm_ioapic_destroy(kvm); kvm_free_vcpus(kvm); |