diff options
| -rw-r--r-- | arch/x86/kvm/mmu/mmu.c | 52 | ||||
| -rw-r--r-- | arch/x86/kvm/mmu/tdp_mmu.c | 6 | ||||
| -rw-r--r-- | arch/x86/kvm/mmu/tdp_mmu.h | 10 |
3 files changed, 43 insertions, 25 deletions
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c index 6f5910b7b9bc..d5b0c8b0e9e9 100644 --- a/arch/x86/kvm/mmu/mmu.c +++ b/arch/x86/kvm/mmu/mmu.c @@ -686,28 +686,36 @@ static bool mmu_spte_age(u64 *sptep) static void walk_shadow_page_lockless_begin(struct kvm_vcpu *vcpu) { - /* - * Prevent page table teardown by making any free-er wait during - * kvm_flush_remote_tlbs() IPI to all active vcpus. - */ - local_irq_disable(); + if (is_tdp_mmu(vcpu->arch.mmu)) { + kvm_tdp_mmu_walk_lockless_begin(); + } else { + /* + * Prevent page table teardown by making any free-er wait during + * kvm_flush_remote_tlbs() IPI to all active vcpus. + */ + local_irq_disable(); - /* - * Make sure a following spte read is not reordered ahead of the write - * to vcpu->mode. - */ - smp_store_mb(vcpu->mode, READING_SHADOW_PAGE_TABLES); + /* + * Make sure a following spte read is not reordered ahead of the write + * to vcpu->mode. + */ + smp_store_mb(vcpu->mode, READING_SHADOW_PAGE_TABLES); + } } static void walk_shadow_page_lockless_end(struct kvm_vcpu *vcpu) { - /* - * Make sure the write to vcpu->mode is not reordered in front of - * reads to sptes. If it does, kvm_mmu_commit_zap_page() can see us - * OUTSIDE_GUEST_MODE and proceed to free the shadow page table. - */ - smp_store_release(&vcpu->mode, OUTSIDE_GUEST_MODE); - local_irq_enable(); + if (is_tdp_mmu(vcpu->arch.mmu)) { + kvm_tdp_mmu_walk_lockless_end(); + } else { + /* + * Make sure the write to vcpu->mode is not reordered in front of + * reads to sptes. If it does, kvm_mmu_commit_zap_page() can see us + * OUTSIDE_GUEST_MODE and proceed to free the shadow page table. + */ + smp_store_release(&vcpu->mode, OUTSIDE_GUEST_MODE); + local_irq_enable(); + } } static int mmu_topup_memory_caches(struct kvm_vcpu *vcpu, bool maybe_indirect) @@ -3617,6 +3625,8 @@ static bool mmio_info_in_cache(struct kvm_vcpu *vcpu, u64 addr, bool direct) /* * Return the level of the lowest level SPTE added to sptes. * That SPTE may be non-present. + * + * Must be called between walk_shadow_page_lockless_{begin,end}. */ static int get_walk(struct kvm_vcpu *vcpu, u64 addr, u64 *sptes, int *root_level) { @@ -3624,8 +3634,6 @@ static int get_walk(struct kvm_vcpu *vcpu, u64 addr, u64 *sptes, int *root_level int leaf = -1; u64 spte; - walk_shadow_page_lockless_begin(vcpu); - for (shadow_walk_init(&iterator, vcpu, addr), *root_level = iterator.level; shadow_walk_okay(&iterator); @@ -3639,8 +3647,6 @@ static int get_walk(struct kvm_vcpu *vcpu, u64 addr, u64 *sptes, int *root_level break; } - walk_shadow_page_lockless_end(vcpu); - return leaf; } @@ -3652,11 +3658,15 @@ static bool get_mmio_spte(struct kvm_vcpu *vcpu, u64 addr, u64 *sptep) int root, leaf, level; bool reserved = false; + walk_shadow_page_lockless_begin(vcpu); + if (is_tdp_mmu(vcpu->arch.mmu)) leaf = kvm_tdp_mmu_get_walk(vcpu, addr, sptes, &root); else leaf = get_walk(vcpu, addr, sptes, &root); + walk_shadow_page_lockless_end(vcpu); + if (unlikely(leaf < 0)) { *sptep = 0ull; return reserved; diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c index 0853370bd811..228f0cc5e2cf 100644 --- a/arch/x86/kvm/mmu/tdp_mmu.c +++ b/arch/x86/kvm/mmu/tdp_mmu.c @@ -1516,6 +1516,8 @@ bool kvm_tdp_mmu_write_protect_gfn(struct kvm *kvm, /* * Return the level of the lowest level SPTE added to sptes. * That SPTE may be non-present. + * + * Must be called between kvm_tdp_mmu_walk_lockless_{begin,end}. */ int kvm_tdp_mmu_get_walk(struct kvm_vcpu *vcpu, u64 addr, u64 *sptes, int *root_level) @@ -1527,14 +1529,10 @@ int kvm_tdp_mmu_get_walk(struct kvm_vcpu *vcpu, u64 addr, u64 *sptes, *root_level = vcpu->arch.mmu->shadow_root_level; - rcu_read_lock(); - tdp_mmu_for_each_pte(iter, mmu, gfn, gfn + 1) { leaf = iter.level; sptes[leaf] = iter.old_spte; } - rcu_read_unlock(); - return leaf; } diff --git a/arch/x86/kvm/mmu/tdp_mmu.h b/arch/x86/kvm/mmu/tdp_mmu.h index 1cae4485b3bc..93e1bf5089c4 100644 --- a/arch/x86/kvm/mmu/tdp_mmu.h +++ b/arch/x86/kvm/mmu/tdp_mmu.h @@ -77,6 +77,16 @@ bool kvm_tdp_mmu_write_protect_gfn(struct kvm *kvm, struct kvm_memory_slot *slot, gfn_t gfn, int min_level); +static inline void kvm_tdp_mmu_walk_lockless_begin(void) +{ + rcu_read_lock(); +} + +static inline void kvm_tdp_mmu_walk_lockless_end(void) +{ + rcu_read_unlock(); +} + int kvm_tdp_mmu_get_walk(struct kvm_vcpu *vcpu, u64 addr, u64 *sptes, int *root_level); |