diff options
Diffstat (limited to 'arch/x86/kvm/mmu/tdp_mmu.c')
| -rw-r--r-- | arch/x86/kvm/mmu/tdp_mmu.c | 45 |
1 files changed, 22 insertions, 23 deletions
diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c index 771210ce5181..7c25dbf32ecc 100644 --- a/arch/x86/kvm/mmu/tdp_mmu.c +++ b/arch/x86/kvm/mmu/tdp_mmu.c @@ -1,4 +1,5 @@ // SPDX-License-Identifier: GPL-2.0 +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include "mmu.h" #include "mmu_internal.h" @@ -10,23 +11,15 @@ #include <asm/cmpxchg.h> #include <trace/events/kvm.h> -static bool __read_mostly tdp_mmu_enabled = true; -module_param_named(tdp_mmu, tdp_mmu_enabled, bool, 0644); - /* Initializes the TDP MMU for the VM, if enabled. */ int kvm_mmu_init_tdp_mmu(struct kvm *kvm) { struct workqueue_struct *wq; - if (!tdp_enabled || !READ_ONCE(tdp_mmu_enabled)) - return 0; - wq = alloc_workqueue("kvm", WQ_UNBOUND|WQ_MEM_RECLAIM|WQ_CPU_INTENSIVE, 0); if (!wq) return -ENOMEM; - /* This should not be changed for the lifetime of the VM. */ - kvm->arch.tdp_mmu_enabled = true; INIT_LIST_HEAD(&kvm->arch.tdp_mmu_roots); spin_lock_init(&kvm->arch.tdp_mmu_pages_lock); kvm->arch.tdp_mmu_zap_wq = wq; @@ -47,9 +40,6 @@ static __always_inline bool kvm_lockdep_assert_mmu_lock_held(struct kvm *kvm, void kvm_mmu_uninit_tdp_mmu(struct kvm *kvm) { - if (!kvm->arch.tdp_mmu_enabled) - return; - /* Also waits for any queued work items. */ destroy_workqueue(kvm->arch.tdp_mmu_zap_wq); @@ -144,7 +134,7 @@ void kvm_tdp_mmu_put_root(struct kvm *kvm, struct kvm_mmu_page *root, if (!refcount_dec_and_test(&root->tdp_mmu_root_count)) return; - WARN_ON(!root->tdp_mmu_page); + WARN_ON(!is_tdp_mmu_page(root)); /* * The root now has refcount=0. It is valid, but readers already @@ -690,8 +680,7 @@ static inline int tdp_mmu_zap_spte_atomic(struct kvm *kvm, if (ret) return ret; - kvm_flush_remote_tlbs_with_address(kvm, iter->gfn, - KVM_PAGES_PER_HPAGE(iter->level)); + kvm_flush_remote_tlbs_gfn(kvm, iter->gfn, iter->level); /* * No other thread can overwrite the removed SPTE as they must either @@ -1074,7 +1063,9 @@ static int tdp_mmu_map_handle_target_level(struct kvm_vcpu *vcpu, int ret = RET_PF_FIXED; bool wrprot = false; - WARN_ON(sp->role.level != fault->goal_level); + if (WARN_ON_ONCE(sp->role.level != fault->goal_level)) + return RET_PF_RETRY; + if (unlikely(!fault->slot)) new_spte = make_mmio_spte(vcpu, iter->gfn, ACC_ALL); else @@ -1088,8 +1079,7 @@ static int tdp_mmu_map_handle_target_level(struct kvm_vcpu *vcpu, return RET_PF_RETRY; else if (is_shadow_present_pte(iter->old_spte) && !is_last_spte(iter->old_spte, iter->level)) - kvm_flush_remote_tlbs_with_address(vcpu->kvm, sp->gfn, - KVM_PAGES_PER_HPAGE(iter->level + 1)); + kvm_flush_remote_tlbs_gfn(vcpu->kvm, iter->gfn, iter->level); /* * If the page fault was caused by a write but the page is write @@ -1173,9 +1163,6 @@ int kvm_tdp_mmu_map(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault) if (fault->nx_huge_page_workaround_enabled) disallowed_hugepage_adjust(fault, iter.old_spte, iter.level); - if (iter.level == fault->goal_level) - break; - /* * If SPTE has been frozen by another thread, just give up and * retry, avoiding unnecessary page table allocation and free. @@ -1183,6 +1170,9 @@ int kvm_tdp_mmu_map(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault) if (is_removed_spte(iter.old_spte)) goto retry; + if (iter.level == fault->goal_level) + goto map_target_level; + /* Step down into the lower level page table if it exists. */ if (is_shadow_present_pte(iter.old_spte) && !is_large_pte(iter.old_spte)) @@ -1203,8 +1193,8 @@ int kvm_tdp_mmu_map(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault) r = tdp_mmu_link_sp(kvm, &iter, sp, true); /* - * Also force the guest to retry the access if the upper level SPTEs - * aren't in place. + * Force the guest to retry if installing an upper level SPTE + * failed, e.g. because a different task modified the SPTE. */ if (r) { tdp_mmu_free_sp(sp); @@ -1214,11 +1204,20 @@ int kvm_tdp_mmu_map(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault) if (fault->huge_page_disallowed && fault->req_level >= iter.level) { spin_lock(&kvm->arch.tdp_mmu_pages_lock); - track_possible_nx_huge_page(kvm, sp); + if (sp->nx_huge_page_disallowed) + track_possible_nx_huge_page(kvm, sp); spin_unlock(&kvm->arch.tdp_mmu_pages_lock); } } + /* + * The walk aborted before reaching the target level, e.g. because the + * iterator detected an upper level SPTE was frozen during traversal. + */ + WARN_ON_ONCE(iter.level == fault->goal_level); + goto retry; + +map_target_level: ret = tdp_mmu_map_handle_target_level(vcpu, fault, &iter); retry: |