diff options
Diffstat (limited to 'arch/x86/kvm/mmu/mmu.c')
| -rw-r--r-- | arch/x86/kvm/mmu/mmu.c | 725 |
1 files changed, 374 insertions, 351 deletions
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c index 2d7e61122af8..323b5057d08f 100644 --- a/arch/x86/kvm/mmu/mmu.c +++ b/arch/x86/kvm/mmu/mmu.c @@ -58,6 +58,7 @@ extern bool itlb_multihit_kvm_mitigation; int __read_mostly nx_huge_pages = -1; +static uint __read_mostly nx_huge_pages_recovery_period_ms; #ifdef CONFIG_PREEMPT_RT /* Recovery can cause latency spikes, disable it for PREEMPT_RT. */ static uint __read_mostly nx_huge_pages_recovery_ratio = 0; @@ -66,23 +67,26 @@ static uint __read_mostly nx_huge_pages_recovery_ratio = 60; #endif static int set_nx_huge_pages(const char *val, const struct kernel_param *kp); -static int set_nx_huge_pages_recovery_ratio(const char *val, const struct kernel_param *kp); +static int set_nx_huge_pages_recovery_param(const char *val, const struct kernel_param *kp); static const struct kernel_param_ops nx_huge_pages_ops = { .set = set_nx_huge_pages, .get = param_get_bool, }; -static const struct kernel_param_ops nx_huge_pages_recovery_ratio_ops = { - .set = set_nx_huge_pages_recovery_ratio, +static const struct kernel_param_ops nx_huge_pages_recovery_param_ops = { + .set = set_nx_huge_pages_recovery_param, .get = param_get_uint, }; module_param_cb(nx_huge_pages, &nx_huge_pages_ops, &nx_huge_pages, 0644); __MODULE_PARM_TYPE(nx_huge_pages, "bool"); -module_param_cb(nx_huge_pages_recovery_ratio, &nx_huge_pages_recovery_ratio_ops, +module_param_cb(nx_huge_pages_recovery_ratio, &nx_huge_pages_recovery_param_ops, &nx_huge_pages_recovery_ratio, 0644); __MODULE_PARM_TYPE(nx_huge_pages_recovery_ratio, "uint"); +module_param_cb(nx_huge_pages_recovery_period_ms, &nx_huge_pages_recovery_param_ops, + &nx_huge_pages_recovery_period_ms, 0644); +__MODULE_PARM_TYPE(nx_huge_pages_recovery_period_ms, "uint"); static bool __read_mostly force_flush_and_sync_on_reuse; module_param_named(flush_on_reuse, force_flush_and_sync_on_reuse, bool, 0644); @@ -1071,20 +1075,6 @@ static bool rmap_can_add(struct kvm_vcpu *vcpu) return kvm_mmu_memory_cache_nr_free_objects(mc); } -static int rmap_add(struct kvm_vcpu *vcpu, u64 *spte, gfn_t gfn) -{ - struct kvm_memory_slot *slot; - struct kvm_mmu_page *sp; - struct kvm_rmap_head *rmap_head; - - sp = sptep_to_sp(spte); - kvm_mmu_page_set_gfn(sp, spte - sp->spt, gfn); - slot = kvm_vcpu_gfn_to_memslot(vcpu, gfn); - rmap_head = gfn_to_rmap(gfn, sp->role.level, slot); - return pte_list_add(vcpu, spte, rmap_head); -} - - static void rmap_remove(struct kvm *kvm, u64 *spte) { struct kvm_memslots *slots; @@ -1097,9 +1087,9 @@ static void rmap_remove(struct kvm *kvm, u64 *spte) gfn = kvm_mmu_page_get_gfn(sp, spte - sp->spt); /* - * Unlike rmap_add and rmap_recycle, rmap_remove does not run in the - * context of a vCPU so have to determine which memslots to use based - * on context information in sp->role. + * Unlike rmap_add, rmap_remove does not run in the context of a vCPU + * so we have to determine which memslots to use based on context + * information in sp->role. */ slots = kvm_memslots_for_spte_role(kvm, sp->role); @@ -1639,19 +1629,23 @@ static bool kvm_test_age_rmapp(struct kvm *kvm, struct kvm_rmap_head *rmap_head, #define RMAP_RECYCLE_THRESHOLD 1000 -static void rmap_recycle(struct kvm_vcpu *vcpu, u64 *spte, gfn_t gfn) +static void rmap_add(struct kvm_vcpu *vcpu, struct kvm_memory_slot *slot, + u64 *spte, gfn_t gfn) { - struct kvm_memory_slot *slot; - struct kvm_rmap_head *rmap_head; struct kvm_mmu_page *sp; + struct kvm_rmap_head *rmap_head; + int rmap_count; sp = sptep_to_sp(spte); - slot = kvm_vcpu_gfn_to_memslot(vcpu, gfn); + kvm_mmu_page_set_gfn(sp, spte - sp->spt, gfn); rmap_head = gfn_to_rmap(gfn, sp->role.level, slot); + rmap_count = pte_list_add(vcpu, spte, rmap_head); - kvm_unmap_rmapp(vcpu->kvm, rmap_head, NULL, gfn, sp->role.level, __pte(0)); - kvm_flush_remote_tlbs_with_address(vcpu->kvm, sp->gfn, - KVM_PAGES_PER_HPAGE(sp->role.level)); + if (rmap_count > RMAP_RECYCLE_THRESHOLD) { + kvm_unmap_rmapp(vcpu->kvm, rmap_head, NULL, gfn, sp->role.level, __pte(0)); + kvm_flush_remote_tlbs_with_address( + vcpu->kvm, sp->gfn, KVM_PAGES_PER_HPAGE(sp->role.level)); + } } bool kvm_age_gfn(struct kvm *kvm, struct kvm_gfn_range *range) @@ -1795,7 +1789,7 @@ static void mark_unsync(u64 *spte) static int nonpaging_sync_page(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp) { - return 0; + return -1; } #define KVM_PAGE_ARRAY_NR 16 @@ -1909,12 +1903,14 @@ static void kvm_mmu_commit_zap_page(struct kvm *kvm, static bool kvm_sync_page(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp, struct list_head *invalid_list) { - if (vcpu->arch.mmu->sync_page(vcpu, sp) == 0) { + int ret = vcpu->arch.mmu->sync_page(vcpu, sp); + + if (ret < 0) { kvm_mmu_prepare_zap_page(vcpu->kvm, sp, invalid_list); return false; } - return true; + return !!ret; } static bool kvm_mmu_remote_flush_or_zap(struct kvm *kvm, @@ -1931,17 +1927,6 @@ static bool kvm_mmu_remote_flush_or_zap(struct kvm *kvm, return true; } -static void kvm_mmu_flush_or_zap(struct kvm_vcpu *vcpu, - struct list_head *invalid_list, - bool remote_flush, bool local_flush) -{ - if (kvm_mmu_remote_flush_or_zap(vcpu->kvm, invalid_list, remote_flush)) - return; - - if (local_flush) - kvm_make_request(KVM_REQ_TLB_FLUSH_CURRENT, vcpu); -} - #ifdef CONFIG_KVM_MMU_AUDIT #include "mmu_audit.c" #else @@ -2027,8 +2012,8 @@ static void mmu_pages_clear_parents(struct mmu_page_path *parents) } while (!sp->unsync_children); } -static void mmu_sync_children(struct kvm_vcpu *vcpu, - struct kvm_mmu_page *parent) +static int mmu_sync_children(struct kvm_vcpu *vcpu, + struct kvm_mmu_page *parent, bool can_yield) { int i; struct kvm_mmu_page *sp; @@ -2044,7 +2029,7 @@ static void mmu_sync_children(struct kvm_vcpu *vcpu, protected |= rmap_write_protect(vcpu, sp->gfn); if (protected) { - kvm_flush_remote_tlbs(vcpu->kvm); + kvm_mmu_remote_flush_or_zap(vcpu->kvm, &invalid_list, true); flush = false; } @@ -2054,13 +2039,19 @@ static void mmu_sync_children(struct kvm_vcpu *vcpu, mmu_pages_clear_parents(&parents); } if (need_resched() || rwlock_needbreak(&vcpu->kvm->mmu_lock)) { - kvm_mmu_flush_or_zap(vcpu, &invalid_list, false, flush); + kvm_mmu_remote_flush_or_zap(vcpu->kvm, &invalid_list, flush); + if (!can_yield) { + kvm_make_request(KVM_REQ_MMU_SYNC, vcpu); + return -EINTR; + } + cond_resched_rwlock_write(&vcpu->kvm->mmu_lock); flush = false; } } - kvm_mmu_flush_or_zap(vcpu, &invalid_list, false, flush); + kvm_mmu_remote_flush_or_zap(vcpu->kvm, &invalid_list, flush); + return 0; } static void __clear_sp_write_flooding_count(struct kvm_mmu_page *sp) @@ -2143,12 +2134,9 @@ static struct kvm_mmu_page *kvm_mmu_get_page(struct kvm_vcpu *vcpu, break; WARN_ON(!list_empty(&invalid_list)); - kvm_make_request(KVM_REQ_TLB_FLUSH_CURRENT, vcpu); + kvm_flush_remote_tlbs(vcpu->kvm); } - if (sp->unsync_children) - kvm_make_request(KVM_REQ_MMU_SYNC, vcpu); - __clear_sp_write_flooding_count(sp); trace_get_page: @@ -2226,7 +2214,7 @@ static bool shadow_walk_okay(struct kvm_shadow_walk_iterator *iterator) static void __shadow_walk_next(struct kvm_shadow_walk_iterator *iterator, u64 spte) { - if (is_last_spte(spte, iterator->level)) { + if (!is_shadow_present_pte(spte) || is_last_spte(spte, iterator->level)) { iterator->level = 0; return; } @@ -2588,7 +2576,8 @@ static void kvm_unsync_page(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp) * were marked unsync (or if there is no shadow page), -EPERM if the SPTE must * be write-protected. */ -int mmu_try_to_unsync_pages(struct kvm_vcpu *vcpu, gfn_t gfn, bool can_unsync) +int mmu_try_to_unsync_pages(struct kvm_vcpu *vcpu, struct kvm_memory_slot *slot, + gfn_t gfn, bool can_unsync, bool prefetch) { struct kvm_mmu_page *sp; bool locked = false; @@ -2598,7 +2587,7 @@ int mmu_try_to_unsync_pages(struct kvm_vcpu *vcpu, gfn_t gfn, bool can_unsync) * track machinery is used to write-protect upper-level shadow pages, * i.e. this guards the role.level == 4K assertion below! */ - if (kvm_page_track_is_active(vcpu, gfn, KVM_PAGE_TRACK_WRITE)) + if (kvm_slot_page_track_is_active(vcpu, slot, gfn, KVM_PAGE_TRACK_WRITE)) return -EPERM; /* @@ -2614,6 +2603,9 @@ int mmu_try_to_unsync_pages(struct kvm_vcpu *vcpu, gfn_t gfn, bool can_unsync) if (sp->unsync) continue; + if (prefetch) + return -EEXIST; + /* * TDP MMU page faults require an additional spinlock as they * run with mmu_lock held for read, not write, and the unsync @@ -2677,48 +2669,30 @@ int mmu_try_to_unsync_pages(struct kvm_vcpu *vcpu, gfn_t gfn, bool can_unsync) * (sp->unsync = true) * * The write barrier below ensures that 1.1 happens before 1.2 and thus - * the situation in 2.4 does not arise. The implicit barrier in 2.2 - * pairs with this write barrier. + * the situation in 2.4 does not arise. It pairs with the read barrier + * in is_unsync_root(), placed between 2.1's load of SPTE.W and 2.3. */ smp_wmb(); return 0; } -static int set_spte(struct kvm_vcpu *vcpu, u64 *sptep, - unsigned int pte_access, int level, - gfn_t gfn, kvm_pfn_t pfn, bool speculative, - bool can_unsync, bool host_writable) -{ - u64 spte; - struct kvm_mmu_page *sp; - int ret; - - sp = sptep_to_sp(sptep); - - ret = make_spte(vcpu, pte_access, level, gfn, pfn, *sptep, speculative, - can_unsync, host_writable, sp_ad_disabled(sp), &spte); - - if (spte & PT_WRITABLE_MASK) - kvm_vcpu_mark_page_dirty(vcpu, gfn); - - if (*sptep == spte) - ret |= SET_SPTE_SPURIOUS; - else if (mmu_spte_update(sptep, spte)) - ret |= SET_SPTE_NEED_REMOTE_TLB_FLUSH; - return ret; -} - -static int mmu_set_spte(struct kvm_vcpu *vcpu, u64 *sptep, - unsigned int pte_access, bool write_fault, int level, - gfn_t gfn, kvm_pfn_t pfn, bool speculative, - bool host_writable) +static int mmu_set_spte(struct kvm_vcpu *vcpu, struct kvm_memory_slot *slot, + u64 *sptep, unsigned int pte_access, gfn_t gfn, + kvm_pfn_t pfn, struct kvm_page_fault *fault) { + struct kvm_mmu_page *sp = sptep_to_sp(sptep); + int level = sp->role.level; int was_rmapped = 0; - int rmap_count; - int set_spte_ret; int ret = RET_PF_FIXED; bool flush = false; + bool wrprot; + u64 spte; + + /* Prefetching always gets a writable pfn. */ + bool host_writable = !fault || fault->map_writable; + bool prefetch = !fault || fault->prefetch; + bool write_fault = fault && fault->write; pgprintk("%s: spte %llx write_fault %d gfn %llx\n", __func__, *sptep, write_fault, gfn); @@ -2749,52 +2723,36 @@ static int mmu_set_spte(struct kvm_vcpu *vcpu, u64 *sptep, was_rmapped = 1; } - set_spte_ret = set_spte(vcpu, sptep, pte_access, level, gfn, pfn, - speculative, true, host_writable); - if (set_spte_ret & SET_SPTE_WRITE_PROTECTED_PT) { + wrprot = make_spte(vcpu, sp, slot, pte_access, gfn, pfn, *sptep, prefetch, + true, host_writable, &spte); + + if (*sptep == spte) { + ret = RET_PF_SPURIOUS; + } else { + trace_kvm_mmu_set_spte(level, gfn, sptep); + flush |= mmu_spte_update(sptep, spte); + } + + if (wrprot) { if (write_fault) ret = RET_PF_EMULATE; - kvm_make_request(KVM_REQ_TLB_FLUSH_CURRENT, vcpu); } - if (set_spte_ret & SET_SPTE_NEED_REMOTE_TLB_FLUSH || flush) + if (flush) kvm_flush_remote_tlbs_with_address(vcpu->kvm, gfn, KVM_PAGES_PER_HPAGE(level)); - /* - * The fault is fully spurious if and only if the new SPTE and old SPTE - * are identical, and emulation is not required. - */ - if ((set_spte_ret & SET_SPTE_SPURIOUS) && ret == RET_PF_FIXED) { - WARN_ON_ONCE(!was_rmapped); - return RET_PF_SPURIOUS; - } - pgprintk("%s: setting spte %llx\n", __func__, *sptep); - trace_kvm_mmu_set_spte(level, gfn, sptep); if (!was_rmapped) { + WARN_ON_ONCE(ret == RET_PF_SPURIOUS); kvm_update_page_stats(vcpu->kvm, level, 1); - rmap_count = rmap_add(vcpu, sptep, gfn); - if (rmap_count > RMAP_RECYCLE_THRESHOLD) - rmap_recycle(vcpu, sptep, gfn); + rmap_add(vcpu, slot, sptep, gfn); } return ret; } -static kvm_pfn_t pte_prefetch_gfn_to_pfn(struct kvm_vcpu *vcpu, gfn_t gfn, - bool no_dirty_log) -{ - struct kvm_memory_slot *slot; - - slot = gfn_to_memslot_dirty_bitmap(vcpu, gfn, no_dirty_log); - if (!slot) - return KVM_PFN_ERR_FAULT; - - return gfn_to_pfn_memslot_atomic(slot, gfn); -} - static int direct_pte_prefetch_many(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp, u64 *start, u64 *end) @@ -2815,8 +2773,8 @@ static int direct_pte_prefetch_many(struct kvm_vcpu *vcpu, return -1; for (i = 0; i < ret; i++, gfn++, start++) { - mmu_set_spte(vcpu, start, access, false, sp->role.level, gfn, - page_to_pfn(pages[i]), true, true); + mmu_set_spte(vcpu, slot, start, access, gfn, + page_to_pfn(pages[i]), NULL); put_page(pages[i]); } @@ -2839,11 +2797,13 @@ static void __direct_pte_prefetch(struct kvm_vcpu *vcpu, if (!start) continue; if (direct_pte_prefetch_many(vcpu, sp, start, spte) < 0) - break; + return; start = NULL; } else if (!start) start = spte; } + if (start) + direct_pte_prefetch_many(vcpu, sp, start, spte); } static void direct_pte_prefetch(struct kvm_vcpu *vcpu, u64 *sptep) @@ -2921,52 +2881,46 @@ int kvm_mmu_max_mapping_level(struct kvm *kvm, return min(host_level, max_level); } -int kvm_mmu_hugepage_adjust(struct kvm_vcpu *vcpu, gfn_t gfn, - int max_level, kvm_pfn_t *pfnp, - bool huge_page_disallowed, int *req_level) +void kvm_mmu_hugepage_adjust(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault) { - struct kvm_memory_slot *slot; - kvm_pfn_t pfn = *pfnp; + struct kvm_memory_slot *slot = fault->slot; kvm_pfn_t mask; - int level; - *req_level = PG_LEVEL_4K; + fault->huge_page_disallowed = fault->exec && fault->nx_huge_page_workaround_enabled; - if (unlikely(max_level == PG_LEVEL_4K)) - return PG_LEVEL_4K; + if (unlikely(fault->max_level == PG_LEVEL_4K)) + return; - if (is_error_noslot_pfn(pfn) || kvm_is_reserved_pfn(pfn)) - return PG_LEVEL_4K; + if (is_error_noslot_pfn(fault->pfn) || kvm_is_reserved_pfn(fault->pfn)) + return; - slot = gfn_to_memslot_dirty_bitmap(vcpu, gfn, true); - if (!slot) - return PG_LEVEL_4K; + if (kvm_slot_dirty_track_enabled(slot)) + return; /* * Enforce the iTLB multihit workaround after capturing the requested * level, which will be used to do precise, accurate accounting. */ - *req_level = level = kvm_mmu_max_mapping_level(vcpu->kvm, slot, gfn, pfn, max_level); - if (level == PG_LEVEL_4K || huge_page_disallowed) - return PG_LEVEL_4K; + fault->req_level = kvm_mmu_max_mapping_level(vcpu->kvm, slot, + fault->gfn, fault->pfn, + fault->max_level); + if (fault->req_level == PG_LEVEL_4K || fault->huge_page_disallowed) + return; /* * mmu_notifier_retry() was successful and mmu_lock is held, so * the pmd can't be split from under us. */ - mask = KVM_PAGES_PER_HPAGE(level) - 1; - VM_BUG_ON((gfn & mask) != (pfn & mask)); - *pfnp = pfn & ~mask; - - return level; + fault->goal_level = fault->req_level; + mask = KVM_PAGES_PER_HPAGE(fault->goal_level) - 1; + VM_BUG_ON((fault->gfn & mask) != (fault->pfn & mask)); + fault->pfn &= ~mask; } -void disallowed_hugepage_adjust(u64 spte, gfn_t gfn, int cur_level, - kvm_pfn_t *pfnp, int *goal_levelp) +void disallowed_hugepage_adjust(struct kvm_page_fault *fault, u64 spte, int cur_level) { - int level = *goal_levelp; - - if (cur_level == level && level > PG_LEVEL_4K && + if (cur_level > PG_LEVEL_4K && + cur_level == fault->goal_level && is_shadow_present_pte(spte) && !is_large_pte(spte)) { /* @@ -2976,42 +2930,33 @@ void disallowed_hugepage_adjust(u64 spte, gfn_t gfn, int cur_level, * patching back for them into pfn the next 9 bits of * the address. */ - u64 page_mask = KVM_PAGES_PER_HPAGE(level) - - KVM_PAGES_PER_HPAGE(level - 1); - *pfnp |= gfn & page_mask; - (*goal_levelp)--; + u64 page_mask = KVM_PAGES_PER_HPAGE(cur_level) - + KVM_PAGES_PER_HPAGE(cur_level - 1); + fault->pfn |= fault->gfn & page_mask; + fault->goal_level--; } } -static int __direct_map(struct kvm_vcpu *vcpu, gpa_t gpa, u32 error_code, - int map_writable, int max_level, kvm_pfn_t pfn, - bool prefault, bool is_tdp) +static int __direct_map(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault) { - bool nx_huge_page_workaround_enabled = is_nx_huge_page_enabled(); - bool write = error_code & PFERR_WRITE_MASK; - bool exec = error_code & PFERR_FETCH_MASK; - bool huge_page_disallowed = exec && nx_huge_page_workaround_enabled; struct kvm_shadow_walk_iterator it; struct kvm_mmu_page *sp; - int level, req_level, ret; - gfn_t gfn = gpa >> PAGE_SHIFT; - gfn_t base_gfn = gfn; + int ret; + gfn_t base_gfn = fault->gfn; - level = kvm_mmu_hugepage_adjust(vcpu, gfn, max_level, &pfn, - huge_page_disallowed, &req_level); + kvm_mmu_hugepage_adjust(vcpu, fault); - trace_kvm_mmu_spte_requested(gpa, level, pfn); - for_each_shadow_entry(vcpu, gpa, it) { + trace_kvm_mmu_spte_requested(fault); + for_each_shadow_entry(vcpu, fault->addr, it) { /* * We cannot overwrite existing page tables with an NX * large page, as the leaf could be executable. */ - if (nx_huge_page_workaround_enabled) - disallowed_hugepage_adjust(*it.sptep, gfn, it.level, - &pfn, &level); + if (fault->nx_huge_page_workaround_enabled) + disallowed_hugepage_adjust(fault, *it.sptep, it.level); - base_gfn = gfn & ~(KVM_PAGES_PER_HPAGE(it.level) - 1); - if (it.level == level) + base_gfn = fault->gfn & ~(KVM_PAGES_PER_HPAGE(it.level) - 1); + if (it.level == fault->goal_level) break; drop_large_spte(vcpu, it.sptep); @@ -3022,14 +2967,16 @@ static int __direct_map(struct kvm_vcpu *vcpu, gpa_t gpa, u32 error_code, it.level - 1, true, ACC_ALL); link_shadow_page(vcpu, it.sptep, sp); - if (is_tdp && huge_page_disallowed && - req_level >= it.level) + if (fault->is_tdp && fault->huge_page_disallowed && + fault->req_level >= it.level) account_huge_nx_page(vcpu->kvm, sp); } - ret = mmu_set_spte(vcpu, it.sptep, ACC_ALL, - write, level, base_gfn, pfn, prefault, - map_writable); + if (WARN_ON_ONCE(it.level != fault->goal_level)) + return -EFAULT; + + ret = mmu_set_spte(vcpu, fault->slot, it.sptep, ACC_ALL, + base_gfn, fault->pfn, fault); if (ret == RET_PF_SPURIOUS) return ret; @@ -3061,18 +3008,19 @@ static int kvm_handle_bad_page(struct kvm_vcpu *vcpu, gfn_t gfn, kvm_pfn_t pfn) return -EFAULT; } -static bool handle_abnormal_pfn(struct kvm_vcpu *vcpu, gva_t gva, gfn_t gfn, - kvm_pfn_t pfn, unsigned int access, - int *ret_val) +static bool handle_abnormal_pfn(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault, + unsigned int access, int *ret_val) { /* The pfn is invalid, report the error! */ - if (unlikely(is_error_pfn(pfn))) { - *ret_val = kvm_handle_bad_page(vcpu, gfn, pfn); + if (unlikely(is_error_pfn(fault->pfn))) { + *ret_val = kvm_handle_bad_page(vcpu, fault->gfn, fault->pfn); return true; } - if (unlikely(is_noslot_pfn(pfn))) { - vcpu_cache_mmio_info(vcpu, gva, gfn, + if (unlikely(!fault->slot)) { + gva_t gva = fault->is_tdp ? 0 : fault->addr; + + vcpu_cache_mmio_info(vcpu, gva, fault->gfn, access & shadow_mmio_access_mask); /* * If MMIO caching is disabled, emulate immediately without @@ -3088,18 +3036,17 @@ static bool handle_abnormal_pfn(struct kvm_vcpu *vcpu, gva_t gva, gfn_t gfn, return false; } -static bool page_fault_can_be_fast(u32 error_code) +static bool page_fault_can_be_fast(struct kvm_page_fault *fault) { /* * Do not fix the mmio spte with invalid generation number which * need to be updated by slow page fault path. */ - if (unlikely(error_code & PFERR_RSVD_MASK)) + if (fault->rsvd) return false; /* See if the page fault is due to an NX violation */ - if (unlikely(((error_code & (PFERR_FETCH_MASK | PFERR_PRESENT_MASK)) - == (PFERR_FETCH_MASK | PFERR_PRESENT_MASK)))) + if (unlikely(fault->exec && fault->present)) return false; /* @@ -3116,9 +3063,7 @@ static bool page_fault_can_be_fast(u32 error_code) * accesses to a present page. */ - return shadow_acc_track_mask != 0 || - ((error_code & (PFERR_WRITE_MASK | PFERR_PRESENT_MASK)) - == (PFERR_WRITE_MASK | PFERR_PRESENT_MASK)); + return shadow_acc_track_mask != 0 || (fault->write && fault->present); } /* @@ -3126,13 +3071,9 @@ static bool page_fault_can_be_fast(u32 error_code) * someone else modified the SPTE from its original value. */ static bool -fast_pf_fix_direct_spte(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp, +fast_pf_fix_direct_spte(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault, u64 *sptep, u64 old_spte, u64 new_spte) { - gfn_t gfn; - - WARN_ON(!sp->role.direct); - /* * Theoretically we could also set dirty bit (and flush TLB) here in * order to eliminate unnecessary PML logging. See comments in @@ -3148,24 +3089,18 @@ fast_pf_fix_direct_spte(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp, if (cmpxchg64(sptep, old_spte, new_spte) != old_spte) return false; - if (is_writable_pte(new_spte) && !is_writable_pte(old_spte)) { - /* - * The gfn of direct spte is stable since it is - * calculated by sp->gfn. - */ - gfn = kvm_mmu_page_get_gfn(sp, sptep - sp->spt); - kvm_vcpu_mark_page_dirty(vcpu, gfn); - } + if (is_writable_pte(new_spte) && !is_writable_pte(old_spte)) + mark_page_dirty_in_slot(vcpu->kvm, fault->slot, fault->gfn); return true; } -static bool is_access_allowed(u32 fault_err_code, u64 spte) +static bool is_access_allowed(struct kvm_page_fault *fault, u64 spte) { - if (fault_err_code & PFERR_FETCH_MASK) + if (fault->exec) return is_executable_pte(spte); - if (fault_err_code & PFERR_WRITE_MASK) + if (fault->write) return is_writable_pte(spte); /* Fault was on Read access */ @@ -3190,9 +3125,6 @@ static u64 *fast_pf_get_last_sptep(struct kvm_vcpu *vcpu, gpa_t gpa, u64 *spte) for_each_shadow_entry_lockless(vcpu, gpa, iterator, old_spte) { sptep = iterator.sptep; *spte = old_spte; - - if (!is_shadow_present_pte(old_spte)) - break; } return sptep; @@ -3201,7 +3133,7 @@ static u64 *fast_pf_get_last_sptep(struct kvm_vcpu *vcpu, gpa_t gpa, u64 *spte) /* * Returns one of RET_PF_INVALID, RET_PF_FIXED or RET_PF_SPURIOUS. */ -static int fast_page_fault(struct kvm_vcpu *vcpu, gpa_t gpa, u32 error_code) +static int fast_page_fault(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault) { struct kvm_mmu_page *sp; int ret = RET_PF_INVALID; @@ -3209,7 +3141,7 @@ static int fast_page_fault(struct kvm_vcpu *vcpu, gpa_t gpa, u32 error_code) u64 *sptep = NULL; uint retry_count = 0; - if (!page_fault_can_be_fast(error_code)) + if (!page_fault_can_be_fast(fault)) return ret; walk_shadow_page_lockless_begin(vcpu); @@ -3218,9 +3150,9 @@ static int fast_page_fault(struct kvm_vcpu *vcpu, gpa_t gpa, u32 error_code) u64 new_spte; if (is_tdp_mmu(vcpu->arch.mmu)) - sptep = kvm_tdp_mmu_fast_pf_get_last_sptep(vcpu, gpa, &spte); + sptep = kvm_tdp_mmu_fast_pf_get_last_sptep(vcpu, fault->addr, &spte); else - sptep = fast_pf_get_last_sptep(vcpu, gpa, &spte); + sptep = fast_pf_get_last_sptep(vcpu, fault->addr, &spte); if (!is_shadow_present_pte(spte)) break; @@ -3239,7 +3171,7 @@ static int fast_page_fault(struct kvm_vcpu *vcpu, gpa_t gpa, u32 error_code) * Need not check the access of upper level table entries since * they are always ACC_ALL. */ - if (is_access_allowed(error_code, spte)) { + if (is_access_allowed(fault, spte)) { ret = RET_PF_SPURIOUS; break; } @@ -3254,7 +3186,7 @@ static int fast_page_fault(struct kvm_vcpu *vcpu, gpa_t gpa, u32 error_code) * be removed in the fast path only if the SPTE was * write-protected for dirty-logging or access tracking. */ - if ((error_code & PFERR_WRITE_MASK) && + if (fault->write && spte_can_locklessly_be_made_writable(spte)) { new_spte |= PT_WRITABLE_MASK; @@ -3275,7 +3207,7 @@ static int fast_page_fault(struct kvm_vcpu *vcpu, gpa_t gpa, u32 error_code) /* Verify that the fault can be handled in the fast path */ if (new_spte == spte || - !is_access_allowed(error_code, new_spte)) + !is_access_allowed(fault, new_spte)) break; /* @@ -3283,7 +3215,7 @@ static int fast_page_fault(struct kvm_vcpu *vcpu, gpa_t gpa, u32 error_code) * since the gfn is not stable for indirect shadow page. See * Documentation/virt/kvm/locking.rst to get more detail. */ - if (fast_pf_fix_direct_spte(vcpu, sp, sptep, spte, new_spte)) { + if (fast_pf_fix_direct_spte(vcpu, fault, sptep, spte, new_spte)) { ret = RET_PF_FIXED; break; } @@ -3296,7 +3228,7 @@ static int fast_page_fault(struct kvm_vcpu *vcpu, gpa_t gpa, u32 error_code) } while (true); - trace_fast_page_fault(vcpu, gpa, error_code, sptep, spte, ret); + trace_fast_page_fault(vcpu, fault, sptep, spte, ret); walk_shadow_page_lockless_end(vcpu); return ret; @@ -3469,6 +3401,67 @@ out_unlock: return r; } +static int mmu_first_shadow_root_alloc(struct kvm *kvm) +{ + struct kvm_memslots *slots; + struct kvm_memory_slot *slot; + int r = 0, i; + + /* + * Check if this is the first shadow root being allocated before + * taking the lock. + */ + if (kvm_shadow_root_allocated(kvm)) + return 0; + + mutex_lock(&kvm->slots_arch_lock); + + /* Recheck, under the lock, whether this is the first shadow root. */ + if (kvm_shadow_root_allocated(kvm)) + goto out_unlock; + + /* + * Check if anything actually needs to be allocated, e.g. all metadata + * will be allocated upfront if TDP is disabled. + */ + if (kvm_memslots_have_rmaps(kvm) && + kvm_page_track_write_tracking_enabled(kvm)) + goto out_success; + + for (i = 0; i < KVM_ADDRESS_SPACE_NUM; i++) { + slots = __kvm_memslots(kvm, i); + kvm_for_each_memslot(slot, slots) { + /* + * Both of these functions are no-ops if the target is + * already allocated, so unconditionally calling both + * is safe. Intentionally do NOT free allocations on + * failure to avoid having to track which allocations + * were made now versus when the memslot was created. + * The metadata is guaranteed to be freed when the slot + * is freed, and will be kept/used if userspace retries + * KVM_RUN instead of killing the VM. + */ + r = memslot_rmap_alloc(slot, slot->npages); + if (r) + goto out_unlock; + r = kvm_page_track_write_tracking_alloc(slot); + if (r) + goto out_unlock; + } + } + + /* + * Ensure that shadow_root_allocated becomes true strictly after + * all the related pointers are set. + */ +out_success: + smp_store_release(&kvm->arch.shadow_root_allocated, true); + +out_unlock: + mutex_unlock(&kvm->slots_arch_lock); + return r; +} + static int mmu_alloc_shadow_roots(struct kvm_vcpu *vcpu) { struct kvm_mmu *mmu = vcpu->arch.mmu; @@ -3499,7 +3492,7 @@ static int mmu_alloc_shadow_roots(struct kvm_vcpu *vcpu) } } - r = alloc_all_memslots_rmaps(vcpu->kvm); + r = mmu_first_shadow_root_alloc(vcpu->kvm); if (r) return r; @@ -3650,6 +3643,33 @@ err_pml4: #endif } +static bool is_unsync_root(hpa_t root) +{ + struct kvm_mmu_page *sp; + + if (!VALID_PAGE(root)) + return false; + + /* + * The read barrier orders the CPU's read of SPTE.W during the page table + * walk before the reads of sp->unsync/sp->unsync_children here. + * + * Even if another CPU was marking the SP as unsync-ed simultaneously, + * any guest page table changes are not guaranteed to be visible anyway + * until this VCPU issues a TLB flush strictly after those changes are + * made. We only need to ensure that the other CPU sets these flags + * before any actual changes to the page tables are made. The comments + * in mmu_try_to_unsync_pages() describe what could go wrong if this + * requirement isn't satisfied. + */ + smp_rmb(); + sp = to_shadow_page(root); + if (sp->unsync || sp->unsync_children) + return true; + + return false; +} + void kvm_mmu_sync_roots(struct kvm_vcpu *vcpu) { int i; @@ -3667,24 +3687,13 @@ void kvm_mmu_sync_roots(struct kvm_vcpu *vcpu) hpa_t root = vcpu->arch.mmu->root_hpa; sp = to_shadow_page(root); - /* - * Even if another CPU was marking the SP as unsync-ed - * simultaneously, any guest page table changes are not - * guaranteed to be visible anyway until this VCPU issues a TLB - * flush strictly after those changes are made. We only need to - * ensure that the other CPU sets these flags before any actual - * changes to the page tables are made. The comments in - * mmu_try_to_unsync_pages() describe what could go wrong if - * this requirement isn't satisfied. - */ - if (!smp_load_acquire(&sp->unsync) && - !smp_load_acquire(&sp->unsync_children)) + if (!is_unsync_root(root)) return; write_lock(&vcpu->kvm->mmu_lock); kvm_mmu_audit(vcpu, AUDIT_PRE_SYNC); - mmu_sync_children(vcpu, sp); + mmu_sync_children(vcpu, sp, true); kvm_mmu_audit(vcpu, AUDIT_POST_SYNC); write_unlock(&vcpu->kvm->mmu_lock); @@ -3700,7 +3709,7 @@ void kvm_mmu_sync_roots(struct kvm_vcpu *vcpu) if (IS_VALID_PAE_ROOT(root)) { root &= PT64_BASE_ADDR_MASK; sp = to_shadow_page(root); - mmu_sync_children(vcpu, sp); + mmu_sync_children(vcpu, sp, true); } } @@ -3708,6 +3717,19 @@ void kvm_mmu_sync_roots(struct kvm_vcpu *vcpu) write_unlock(&vcpu->kvm->mmu_lock); } +void kvm_mmu_sync_prev_roots(struct kvm_vcpu *vcpu) +{ + unsigned long roots_to_free = 0; + int i; + + for (i = 0; i < KVM_MMU_NUM_PREV_ROOTS; i++) + if (is_unsync_root(vcpu->arch.mmu->prev_roots[i].hpa)) + roots_to_free |= KVM_MMU_ROOT_PREVIOUS(i); + + /* sync prev_roots by simply freeing them */ + kvm_mmu_free_roots(vcpu, vcpu->arch.mmu, roots_to_free); +} + static gpa_t nonpaging_gva_to_gpa(struct kvm_vcpu *vcpu, gpa_t vaddr, u32 access, struct x86_exception *exception) { @@ -3760,9 +3782,6 @@ static int get_walk(struct kvm_vcpu *vcpu, u64 addr, u64 *sptes, int *root_level spte = mmu_spte_get_lockless(iterator.sptep); sptes[leaf] = spte; - - if (!is_shadow_present_pte(spte)) - break; } return leaf; @@ -3853,20 +3872,19 @@ static int handle_mmio_page_fault(struct kvm_vcpu *vcpu, u64 addr, bool direct) } static bool page_fault_handle_page_track(struct kvm_vcpu *vcpu, - u32 error_code, gfn_t gfn) + struct kvm_page_fault *fault) { - if (unlikely(error_code & PFERR_RSVD_MASK)) + if (unlikely(fault->rsvd)) return false; - if (!(error_code & PFERR_PRESENT_MASK) || - !(error_code & PFERR_WRITE_MASK)) + if (!fault->present || !fault->write) return false; /* * guest is writing the page which is write tracked which can * not be fixed by page fault handler. */ - if (kvm_page_track_is_active(vcpu, gfn, KVM_PAGE_TRACK_WRITE)) + if (kvm_slot_page_track_is_active(vcpu, fault->slot, fault->gfn, KVM_PAGE_TRACK_WRITE)) return true; return false; @@ -3878,11 +3896,8 @@ static void shadow_page_table_clear_flood(struct kvm_vcpu *vcpu, gva_t addr) u64 spte; walk_shadow_page_lockless_begin(vcpu); - for_each_shadow_entry_lockless(vcpu, addr, iterator, spte) { + for_each_shadow_entry_lockless(vcpu, addr, iterator, spte) clear_sp_write_flooding_count(iterator.sptep); - if (!is_shadow_present_pte(spte)) - break; - } walk_shadow_page_lockless_end(vcpu); } @@ -3900,11 +3915,9 @@ static bool kvm_arch_setup_async_pf(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa, kvm_vcpu_gfn_to_hva(vcpu, gfn), &arch); } -static bool kvm_faultin_pfn(struct kvm_vcpu *vcpu, bool prefault, gfn_t gfn, - gpa_t cr2_or_gpa, kvm_pfn_t *pfn, hva_t *hva, - bool write, bool *writable, int *r) +static bool kvm_faultin_pfn(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault, int *r) { - struct kvm_memory_slot *slot = kvm_vcpu_gfn_to_memslot(vcpu, gfn); + struct kvm_memory_slot *slot = fault->slot; bool async; /* @@ -3918,8 +3931,9 @@ static bool kvm_faultin_pfn(struct kvm_vcpu *vcpu, bool prefault, gfn_t gfn, if (!kvm_is_visible_memslot(slot)) { /* Don't expose private memslots to L2. */ if (is_guest_mode(vcpu)) { - *pfn = KVM_PFN_NOSLOT; - *writable = false; + fault->slot = NULL; + fault->pfn = KVM_PFN_NOSLOT; + fault->map_writable = false; return false; } /* @@ -3936,46 +3950,46 @@ static bool kvm_faultin_pfn(struct kvm_vcpu *vcpu, bool prefault, gfn_t gfn, } async = false; - *pfn = __gfn_to_pfn_memslot(slot, gfn, false, &async, - write, writable, hva); + fault->pfn = __gfn_to_pfn_memslot(slot, fault->gfn, false, &async, + fault->write, &fault->map_writable, + &fault->hva); if (!async) return false; /* *pfn has correct page already */ - if (!prefault && kvm_can_do_async_pf(vcpu)) { - trace_kvm_try_async_get_page(cr2_or_gpa, gfn); - if (kvm_find_async_pf_gfn(vcpu, gfn)) { - trace_kvm_async_pf_doublefault(cr2_or_gpa, gfn); + if (!fault->prefetch && kvm_can_do_async_pf(vcpu)) { + trace_kvm_try_async_get_page(fault->addr, fault->gfn); + if (kvm_find_async_pf_gfn(vcpu, fault->gfn)) { + trace_kvm_async_pf_doublefault(fault->addr, fault->gfn); kvm_make_request(KVM_REQ_APF_HALT, vcpu); goto out_retry; - } else if (kvm_arch_setup_async_pf(vcpu, cr2_or_gpa, gfn)) + } else if (kvm_arch_setup_async_pf(vcpu, fault->addr, fault->gfn)) goto out_retry; } - *pfn = __gfn_to_pfn_memslot(slot, gfn, false, NULL, - write, writable, hva); + fault->pfn = __gfn_to_pfn_memslot(slot, fault->gfn, false, NULL, + fault->write, &fault->map_writable, + &fault->hva); + return false; out_retry: *r = RET_PF_RETRY; return true; } -static int direct_page_fault(struct kvm_vcpu *vcpu, gpa_t gpa, u32 error_code, - bool prefault, int max_level, bool is_tdp) +static int direct_page_fault(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault) { bool is_tdp_mmu_fault = is_tdp_mmu(vcpu->arch.mmu); - bool write = error_code & PFERR_WRITE_MASK; - bool map_writable; - gfn_t gfn = gpa >> PAGE_SHIFT; unsigned long mmu_seq; - kvm_pfn_t pfn; - hva_t hva; int r; - if (page_fault_handle_page_track(vcpu, error_code, gfn)) + fault->gfn = fault->addr >> PAGE_SHIFT; + fault->slot = kvm_vcpu_gfn_to_memslot(vcpu, fault->gfn); + + if (page_fault_handle_page_track(vcpu, fault)) return RET_PF_EMULATE; - r = fast_page_fault(vcpu, gpa, error_code); + r = fast_page_fault(vcpu, fault); if (r != RET_PF_INVALID) return r; @@ -3986,11 +4000,10 @@ static int direct_page_fault(struct kvm_vcpu *vcpu, gpa_t gpa, u32 error_code, mmu_seq = vcpu->kvm->mmu_notifier_seq; smp_rmb(); - if (kvm_faultin_pfn(vcpu, prefault, gfn, gpa, &pfn, &hva, - write, &map_writable, &r)) + if (kvm_faultin_pfn(vcpu, fault, &r)) return r; - if (handle_abnormal_pfn(vcpu, is_tdp ? 0 : gpa, gfn, pfn, ACC_ALL, &r)) + if (handle_abnormal_pfn(vcpu, fault, ACC_ALL, &r)) return r; r = RET_PF_RETRY; @@ -4000,36 +4013,34 @@ static int direct_page_fault(struct kvm_vcpu *vcpu, gpa_t gpa, u32 error_code, else write_lock(&vcpu->kvm->mmu_lock); - if (!is_noslot_pfn(pfn) && mmu_notifier_retry_hva(vcpu->kvm, mmu_seq, hva)) + if (fault->slot && mmu_notifier_retry_hva(vcpu->kvm, mmu_seq, fault->hva)) goto out_unlock; r = make_mmu_pages_available(vcpu); if (r) goto out_unlock; if (is_tdp_mmu_fault) - r = kvm_tdp_mmu_map(vcpu, gpa, error_code, map_writable, max_level, - pfn, prefault); + r = kvm_tdp_mmu_map(vcpu, fault); else - r = __direct_map(vcpu, gpa, error_code, map_writable, max_level, pfn, - prefault, is_tdp); + r = __direct_map(vcpu, fault); out_unlock: if (is_tdp_mmu_fault) read_unlock(&vcpu->kvm->mmu_lock); else write_unlock(&vcpu->kvm->mmu_lock); - kvm_release_pfn_clean(pfn); + kvm_release_pfn_clean(fault->pfn); return r; } -static int nonpaging_page_fault(struct kvm_vcpu *vcpu, gpa_t gpa, - u32 error_code, bool prefault) +static int nonpaging_page_fault(struct kvm_vcpu *vcpu, + struct kvm_page_fault *fault) { - pgprintk("%s: gva %lx error %x\n", __func__, gpa, error_code); + pgprintk("%s: gva %lx error %x\n", __func__, fault->addr, fault->error_code); /* This path builds a PAE pagetable, we can map 2mb pages at maximum. */ - return direct_page_fault(vcpu, gpa & PAGE_MASK, error_code, prefault, - PG_LEVEL_2M, false); + fault->max_level = PG_LEVEL_2M; + return direct_page_fault(vcpu, fault); } int kvm_handle_page_fault(struct kvm_vcpu *vcpu, u64 error_code, @@ -4065,23 +4076,19 @@ int kvm_handle_page_fault(struct kvm_vcpu *vcpu, u64 error_code, } EXPORT_SYMBOL_GPL(kvm_handle_page_fault); -int kvm_tdp_page_fault(struct kvm_vcpu *vcpu, gpa_t gpa, u32 error_code, - bool prefault) +int kvm_tdp_page_fault(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault) { - int max_level; - - for (max_level = KVM_MAX_HUGEPAGE_LEVEL; - max_level > PG_LEVEL_4K; - max_level--) { - int page_num = KVM_PAGES_PER_HPAGE(max_level); - gfn_t base = (gpa >> PAGE_SHIFT) & ~(page_num - 1); + while (fault->max_level > PG_LEVEL_4K) { + int page_num = KVM_PAGES_PER_HPAGE(fault->max_level); + gfn_t base = (fault->addr >> PAGE_SHIFT) & ~(page_num - 1); if (kvm_mtrr_check_gfn_range_consistency(vcpu, base, page_num)) break; + + --fault->max_level; } - return direct_page_fault(vcpu, gpa, error_code, prefault, - max_level, true); + return direct_page_fault(vcpu, fault); } static void nonpaging_init_context(struct kvm_mmu *context) @@ -4202,7 +4209,7 @@ static unsigned long get_cr3(struct kvm_vcpu *vcpu) } static bool sync_mmio_spte(struct kvm_vcpu *vcpu, u64 *sptep, gfn_t gfn, - unsigned int access, int *nr_present) + unsigned int access) { if (unlikely(is_mmio_spte(*sptep))) { if (gfn != get_mmio_spte_gfn(*sptep)) { @@ -4210,7 +4217,6 @@ static bool sync_mmio_spte(struct kvm_vcpu *vcpu, u64 *sptep, gfn_t gfn, return true; } - (*nr_present)++; mark_mmio_spte(vcpu, sptep, gfn, access); return true; } @@ -4593,10 +4599,10 @@ static void update_pkru_bitmask(struct kvm_mmu *mmu) unsigned bit; bool wp; - if (!is_cr4_pke(mmu)) { - mmu->pkru_mask = 0; + mmu->pkru_mask = 0; + + if (!is_cr4_pke(mmu)) return; - } wp = is_cr0_wp(mmu); @@ -5209,7 +5215,7 @@ static void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa, LIST_HEAD(invalid_list); u64 entry, gentry, *spte; int npte; - bool remote_flush, local_flush; + bool flush = false; /* * If we don't have indirect shadow pages, it means no page is @@ -5218,8 +5224,6 @@ static void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa, if (!READ_ONCE(vcpu->kvm->arch.indirect_shadow_pages)) return; - remote_flush = local_flush = false; - pgprintk("%s: gpa %llx bytes %d\n", __func__, gpa, bytes); /* @@ -5248,18 +5252,17 @@ static void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa, if (!spte) continue; - local_flush = true; while (npte--) { entry = *spte; mmu_page_zap_pte(vcpu->kvm, sp, spte, NULL); if (gentry && sp->role.level != PG_LEVEL_4K) ++vcpu->kvm->stat.mmu_pde_zapped; if (need_remote_flush(entry, *spte)) - remote_flush = true; + flush = true; ++spte; } } - kvm_mmu_flush_or_zap(vcpu, &invalid_list, remote_flush, local_flush); + kvm_mmu_remote_flush_or_zap(vcpu->kvm, &invalid_list, flush); kvm_mmu_audit(vcpu, AUDIT_POST_PTE_WRITE); write_unlock(&vcpu->kvm->mmu_lock); } @@ -5470,8 +5473,8 @@ slot_handle_level(struct kvm *kvm, const struct kvm_memory_slot *memslot, } static __always_inline bool -slot_handle_leaf(struct kvm *kvm, const struct kvm_memory_slot *memslot, - slot_level_handler fn, bool flush_on_yield) +slot_handle_level_4k(struct kvm *kvm, const struct kvm_memory_slot *memslot, + slot_level_handler fn, bool flush_on_yield) { return slot_handle_level(kvm, memslot, fn, PG_LEVEL_4K, PG_LEVEL_4K, flush_on_yield); @@ -5691,13 +5694,7 @@ void kvm_mmu_init_vm(struct kvm *kvm) spin_lock_init(&kvm->arch.mmu_unsync_pages_lock); - if (!kvm_mmu_init_tdp_mmu(kvm)) - /* - * No smp_load/store wrappers needed here as we are in - * VM init and there cannot be any memslots / other threads - * accessing this struct kvm yet. - */ - kvm->arch.memslots_have_rmaps = true; + kvm_mmu_init_tdp_mmu(kvm); node->track_write = kvm_mmu_pte_write; node->track_flush_slot = kvm_mmu_invalidate_zap_pages_in_memslot; @@ -5713,55 +5710,58 @@ void kvm_mmu_uninit_vm(struct kvm *kvm) kvm_mmu_uninit_tdp_mmu(kvm); } +static bool __kvm_zap_rmaps(struct kvm *kvm, gfn_t gfn_start, gfn_t gfn_end) +{ + const struct kvm_memory_slot *memslot; + struct kvm_memslots *slots; + bool flush = false; + gfn_t start, end; + int i; + + if (!kvm_memslots_have_rmaps(kvm)) + return flush; + + for (i = 0; i < KVM_ADDRESS_SPACE_NUM; i++) { + slots = __kvm_memslots(kvm, i); + kvm_for_each_memslot(memslot, slots) { + start = max(gfn_start, memslot->base_gfn); + end = min(gfn_end, memslot->base_gfn + memslot->npages); + if (start >= end) + continue; + + flush = slot_handle_level_range(kvm, memslot, kvm_zap_rmapp, + PG_LEVEL_4K, KVM_MAX_HUGEPAGE_LEVEL, + start, end - 1, true, flush); + } + } + + return flush; +} + /* * Invalidate (zap) SPTEs that cover GFNs from gfn_start and up to gfn_end * (not including it) */ void kvm_zap_gfn_range(struct kvm *kvm, gfn_t gfn_start, gfn_t gfn_end) { - struct kvm_memslots *slots; - struct kvm_memory_slot *memslot; + bool flush; int i; - bool flush = false; write_lock(&kvm->mmu_lock); kvm_inc_notifier_count(kvm, gfn_start, gfn_end); - if (kvm_memslots_have_rmaps(kvm)) { - for (i = 0; i < KVM_ADDRESS_SPACE_NUM; i++) { - slots = __kvm_memslots(kvm, i); - kvm_for_each_memslot(memslot, slots) { - gfn_t start, end; - - start = max(gfn_start, memslot->base_gfn); - end = min(gfn_end, memslot->base_gfn + memslot->npages); - if (start >= end) - continue; - - flush = slot_handle_level_range(kvm, - (const struct kvm_memory_slot *) memslot, - kvm_zap_rmapp, PG_LEVEL_4K, - KVM_MAX_HUGEPAGE_LEVEL, start, - end - 1, true, flush); - } - } - if (flush) - kvm_flush_remote_tlbs_with_address(kvm, gfn_start, - gfn_end - gfn_start); - } + flush = __kvm_zap_rmaps(kvm, gfn_start, gfn_end); if (is_tdp_mmu_enabled(kvm)) { for (i = 0; i < KVM_ADDRESS_SPACE_NUM; i++) flush = kvm_tdp_mmu_zap_gfn_range(kvm, i, gfn_start, gfn_end, flush); - if (flush) - kvm_flush_remote_tlbs_with_address(kvm, gfn_start, - gfn_end - gfn_start); } if (flush) - kvm_flush_remote_tlbs_with_address(kvm, gfn_start, gfn_end); + kvm_flush_remote_tlbs_with_address(kvm, gfn_start, + gfn_end - gfn_start); kvm_dec_notifier_count(kvm, gfn_start, gfn_end); @@ -5857,7 +5857,12 @@ void kvm_mmu_zap_collapsible_sptes(struct kvm *kvm, if (kvm_memslots_have_rmaps(kvm)) { write_lock(&kvm->mmu_lock); - flush = slot_handle_leaf(kvm, slot, kvm_mmu_zap_collapsible_spte, true); + /* + * Zap only 4k SPTEs since the legacy MMU only supports dirty + * logging at a 4k granularity and never creates collapsible + * 2m SPTEs during dirty logging. + */ + flush = slot_handle_level_4k(kvm, slot, kvm_mmu_zap_collapsible_spte, true); if (flush) kvm_arch_flush_remote_tlbs_memslot(kvm, slot); write_unlock(&kvm->mmu_lock); @@ -5894,8 +5899,11 @@ void kvm_mmu_slot_leaf_clear_dirty(struct kvm *kvm, if (kvm_memslots_have_rmaps(kvm)) { write_lock(&kvm->mmu_lock); - flush = slot_handle_leaf(kvm, memslot, __rmap_clear_dirty, - false); + /* + * Clear dirty bits only on 4k SPTEs since the legacy MMU only + * support dirty logging at a 4k granularity. + */ + flush = slot_handle_level_4k(kvm, memslot, __rmap_clear_dirty, false); write_unlock(&kvm->mmu_lock); } @@ -6173,18 +6181,24 @@ void kvm_mmu_module_exit(void) mmu_audit_disable(); } -static int set_nx_huge_pages_recovery_ratio(const char *val, const struct kernel_param *kp) +static int set_nx_huge_pages_recovery_param(const char *val, const struct kernel_param *kp) { - unsigned int old_val; + bool was_recovery_enabled, is_recovery_enabled; + uint old_period, new_period; int err; - old_val = nx_huge_pages_recovery_ratio; + was_recovery_enabled = nx_huge_pages_recovery_ratio; + old_period = nx_huge_pages_recovery_period_ms; + err = param_set_uint(val, kp); if (err) return err; - if (READ_ONCE(nx_huge_pages) && - !old_val && nx_huge_pages_recovery_ratio) { + is_recovery_enabled = nx_huge_pages_recovery_ratio; + new_period = nx_huge_pages_recovery_period_ms; + + if (READ_ONCE(nx_huge_pages) && is_recovery_enabled && + (!was_recovery_enabled || old_period > new_period)) { struct kvm *kvm; mutex_lock(&kvm_lock); @@ -6247,8 +6261,17 @@ static void kvm_recover_nx_lpages(struct kvm *kvm) static long get_nx_lpage_recovery_timeout(u64 start_time) { - return READ_ONCE(nx_huge_pages) && READ_ONCE(nx_huge_pages_recovery_ratio) - ? start_time + 60 * HZ - get_jiffies_64() + uint ratio = READ_ONCE(nx_huge_pages_recovery_ratio); + uint period = READ_ONCE(nx_huge_pages_recovery_period_ms); + + if (!period && ratio) { + /* Make sure the period is not less than one second. */ + ratio = min(ratio, 3600u); + period = 60 * 60 * 1000 / ratio; + } + + return READ_ONCE(nx_huge_pages) && ratio + ? start_time + msecs_to_jiffies(period) - get_jiffies_64() : MAX_SCHEDULE_TIMEOUT; } |