diff options
Diffstat (limited to 'arch/x86/kvm/mmu.c')
-rw-r--r-- | arch/x86/kvm/mmu.c | 613 |
1 files changed, 338 insertions, 275 deletions
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index 7c03c0f35444..d9c7b45d231f 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -109,9 +109,11 @@ module_param(dbg, bool, 0644); (((address) >> PT32_LEVEL_SHIFT(level)) & ((1 << PT32_LEVEL_BITS) - 1)) -#define PT64_BASE_ADDR_MASK __sme_clr((((1ULL << 52) - 1) & ~(u64)(PAGE_SIZE-1))) -#define PT64_DIR_BASE_ADDR_MASK \ - (PT64_BASE_ADDR_MASK & ~((1ULL << (PAGE_SHIFT + PT64_LEVEL_BITS)) - 1)) +#ifdef CONFIG_DYNAMIC_PHYSICAL_MASK +#define PT64_BASE_ADDR_MASK (physical_mask & ~(u64)(PAGE_SIZE-1)) +#else +#define PT64_BASE_ADDR_MASK (((1ULL << 52) - 1) & ~(u64)(PAGE_SIZE-1)) +#endif #define PT64_LVL_ADDR_MASK(level) \ (PT64_BASE_ADDR_MASK & ~((1ULL << (PAGE_SHIFT + (((level) - 1) \ * PT64_LEVEL_BITS))) - 1)) @@ -180,7 +182,7 @@ struct kvm_shadow_walk_iterator { static const union kvm_mmu_page_role mmu_base_role_mask = { .cr0_wp = 1, - .cr4_pae = 1, + .gpte_is_8_bytes = 1, .nxe = 1, .smep_andnot_wp = 1, .smap_andnot_wp = 1, @@ -264,6 +266,35 @@ static void mmu_spte_set(u64 *sptep, u64 spte); static union kvm_mmu_page_role kvm_mmu_calc_root_page_role(struct kvm_vcpu *vcpu); + +static inline bool kvm_available_flush_tlb_with_range(void) +{ + return kvm_x86_ops->tlb_remote_flush_with_range; +} + +static void kvm_flush_remote_tlbs_with_range(struct kvm *kvm, + struct kvm_tlb_range *range) +{ + int ret = -ENOTSUPP; + + if (range && kvm_x86_ops->tlb_remote_flush_with_range) + ret = kvm_x86_ops->tlb_remote_flush_with_range(kvm, range); + + if (ret) + kvm_flush_remote_tlbs(kvm); +} + +static void kvm_flush_remote_tlbs_with_address(struct kvm *kvm, + u64 start_gfn, u64 pages) +{ + struct kvm_tlb_range range; + + range.start_gfn = start_gfn; + range.pages = pages; + + kvm_flush_remote_tlbs_with_range(kvm, &range); +} + void kvm_mmu_set_mmio_spte_mask(u64 mmio_mask, u64 mmio_value) { BUG_ON((mmio_mask & mmio_value) != mmio_value); @@ -301,53 +332,56 @@ static inline bool is_access_track_spte(u64 spte) } /* - * the low bit of the generation number is always presumed to be zero. - * This disables mmio caching during memslot updates. The concept is - * similar to a seqcount but instead of retrying the access we just punt - * and ignore the cache. + * Due to limited space in PTEs, the MMIO generation is a 19 bit subset of + * the memslots generation and is derived as follows: * - * spte bits 3-11 are used as bits 1-9 of the generation number, - * the bits 52-61 are used as bits 10-19 of the generation number. + * Bits 0-8 of the MMIO generation are propagated to spte bits 3-11 + * Bits 9-18 of the MMIO generation are propagated to spte bits 52-61 + * + * The KVM_MEMSLOT_GEN_UPDATE_IN_PROGRESS flag is intentionally not included in + * the MMIO generation number, as doing so would require stealing a bit from + * the "real" generation number and thus effectively halve the maximum number + * of MMIO generations that can be handled before encountering a wrap (which + * requires a full MMU zap). The flag is instead explicitly queried when + * checking for MMIO spte cache hits. */ -#define MMIO_SPTE_GEN_LOW_SHIFT 2 -#define MMIO_SPTE_GEN_HIGH_SHIFT 52 +#define MMIO_SPTE_GEN_MASK GENMASK_ULL(18, 0) -#define MMIO_GEN_SHIFT 20 -#define MMIO_GEN_LOW_SHIFT 10 -#define MMIO_GEN_LOW_MASK ((1 << MMIO_GEN_LOW_SHIFT) - 2) -#define MMIO_GEN_MASK ((1 << MMIO_GEN_SHIFT) - 1) +#define MMIO_SPTE_GEN_LOW_START 3 +#define MMIO_SPTE_GEN_LOW_END 11 +#define MMIO_SPTE_GEN_LOW_MASK GENMASK_ULL(MMIO_SPTE_GEN_LOW_END, \ + MMIO_SPTE_GEN_LOW_START) -static u64 generation_mmio_spte_mask(unsigned int gen) +#define MMIO_SPTE_GEN_HIGH_START 52 +#define MMIO_SPTE_GEN_HIGH_END 61 +#define MMIO_SPTE_GEN_HIGH_MASK GENMASK_ULL(MMIO_SPTE_GEN_HIGH_END, \ + MMIO_SPTE_GEN_HIGH_START) +static u64 generation_mmio_spte_mask(u64 gen) { u64 mask; - WARN_ON(gen & ~MMIO_GEN_MASK); + WARN_ON(gen & ~MMIO_SPTE_GEN_MASK); - mask = (gen & MMIO_GEN_LOW_MASK) << MMIO_SPTE_GEN_LOW_SHIFT; - mask |= ((u64)gen >> MMIO_GEN_LOW_SHIFT) << MMIO_SPTE_GEN_HIGH_SHIFT; + mask = (gen << MMIO_SPTE_GEN_LOW_START) & MMIO_SPTE_GEN_LOW_MASK; + mask |= (gen << MMIO_SPTE_GEN_HIGH_START) & MMIO_SPTE_GEN_HIGH_MASK; return mask; } -static unsigned int get_mmio_spte_generation(u64 spte) +static u64 get_mmio_spte_generation(u64 spte) { - unsigned int gen; + u64 gen; spte &= ~shadow_mmio_mask; - gen = (spte >> MMIO_SPTE_GEN_LOW_SHIFT) & MMIO_GEN_LOW_MASK; - gen |= (spte >> MMIO_SPTE_GEN_HIGH_SHIFT) << MMIO_GEN_LOW_SHIFT; + gen = (spte & MMIO_SPTE_GEN_LOW_MASK) >> MMIO_SPTE_GEN_LOW_START; + gen |= (spte & MMIO_SPTE_GEN_HIGH_MASK) >> MMIO_SPTE_GEN_HIGH_START; return gen; } -static unsigned int kvm_current_mmio_generation(struct kvm_vcpu *vcpu) -{ - return kvm_vcpu_memslots(vcpu)->generation & MMIO_GEN_MASK; -} - static void mark_mmio_spte(struct kvm_vcpu *vcpu, u64 *sptep, u64 gfn, unsigned access) { - unsigned int gen = kvm_current_mmio_generation(vcpu); + u64 gen = kvm_vcpu_memslots(vcpu)->generation & MMIO_SPTE_GEN_MASK; u64 mask = generation_mmio_spte_mask(gen); u64 gpa = gfn << PAGE_SHIFT; @@ -357,6 +391,8 @@ static void mark_mmio_spte(struct kvm_vcpu *vcpu, u64 *sptep, u64 gfn, mask |= (gpa & shadow_nonpresent_or_rsvd_mask) << shadow_nonpresent_or_rsvd_mask_len; + page_header(__pa(sptep))->mmio_cached = true; + trace_mark_mmio_spte(sptep, gfn, access, gen); mmu_spte_set(sptep, mask); } @@ -378,7 +414,7 @@ static gfn_t get_mmio_spte_gfn(u64 spte) static unsigned get_mmio_spte_access(u64 spte) { - u64 mask = generation_mmio_spte_mask(MMIO_GEN_MASK) | shadow_mmio_mask; + u64 mask = generation_mmio_spte_mask(MMIO_SPTE_GEN_MASK) | shadow_mmio_mask; return (spte & ~mask) & ~PAGE_MASK; } @@ -395,9 +431,13 @@ static bool set_mmio_spte(struct kvm_vcpu *vcpu, u64 *sptep, gfn_t gfn, static bool check_mmio_spte(struct kvm_vcpu *vcpu, u64 spte) { - unsigned int kvm_gen, spte_gen; + u64 kvm_gen, spte_gen, gen; - kvm_gen = kvm_current_mmio_generation(vcpu); + gen = kvm_vcpu_memslots(vcpu)->generation; + if (unlikely(gen & KVM_MEMSLOT_GEN_UPDATE_IN_PROGRESS)) + return false; + + kvm_gen = gen & MMIO_SPTE_GEN_MASK; spte_gen = get_mmio_spte_generation(spte); trace_check_mmio_spte(spte, kvm_gen, spte_gen); @@ -930,7 +970,7 @@ static int mmu_topup_memory_cache(struct kvm_mmu_memory_cache *cache, if (cache->nobjs >= min) return 0; while (cache->nobjs < ARRAY_SIZE(cache->objects)) { - obj = kmem_cache_zalloc(base_cache, GFP_KERNEL); + obj = kmem_cache_zalloc(base_cache, GFP_KERNEL_ACCOUNT); if (!obj) return cache->nobjs >= min ? 0 : -ENOMEM; cache->objects[cache->nobjs++] = obj; @@ -1456,8 +1496,12 @@ static bool __drop_large_spte(struct kvm *kvm, u64 *sptep) static void drop_large_spte(struct kvm_vcpu *vcpu, u64 *sptep) { - if (__drop_large_spte(vcpu->kvm, sptep)) - kvm_flush_remote_tlbs(vcpu->kvm); + if (__drop_large_spte(vcpu->kvm, sptep)) { + struct kvm_mmu_page *sp = page_header(__pa(sptep)); + + kvm_flush_remote_tlbs_with_address(vcpu->kvm, sp->gfn, + KVM_PAGES_PER_HPAGE(sp->role.level)); + } } /* @@ -1743,10 +1787,12 @@ restart: } } - if (need_flush) - kvm_flush_remote_tlbs(kvm); + if (need_flush && kvm_available_flush_tlb_with_range()) { + kvm_flush_remote_tlbs_with_address(kvm, gfn, 1); + return 0; + } - return 0; + return need_flush; } struct slot_rmap_walk_iterator { @@ -1880,9 +1926,9 @@ int kvm_unmap_hva_range(struct kvm *kvm, unsigned long start, unsigned long end) return kvm_handle_hva_range(kvm, start, end, 0, kvm_unmap_rmapp); } -void kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte) +int kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte) { - kvm_handle_hva(kvm, hva, (unsigned long)&pte, kvm_set_pte_rmapp); + return kvm_handle_hva(kvm, hva, (unsigned long)&pte, kvm_set_pte_rmapp); } static int kvm_age_rmapp(struct kvm *kvm, struct kvm_rmap_head *rmap_head, @@ -1925,7 +1971,8 @@ static void rmap_recycle(struct kvm_vcpu *vcpu, u64 *spte, gfn_t gfn) rmap_head = gfn_to_rmap(vcpu->kvm, gfn, sp); kvm_unmap_rmapp(vcpu->kvm, rmap_head, NULL, gfn, sp->role.level, 0); - kvm_flush_remote_tlbs(vcpu->kvm); + kvm_flush_remote_tlbs_with_address(vcpu->kvm, sp->gfn, + KVM_PAGES_PER_HPAGE(sp->role.level)); } int kvm_age_hva(struct kvm *kvm, unsigned long start, unsigned long end) @@ -1960,7 +2007,7 @@ static int is_empty_shadow_page(u64 *spt) * aggregate version in order to make the slab shrinker * faster */ -static inline void kvm_mod_used_mmu_pages(struct kvm *kvm, int nr) +static inline void kvm_mod_used_mmu_pages(struct kvm *kvm, unsigned long nr) { kvm->arch.n_used_mmu_pages += nr; percpu_counter_add(&kvm_total_used_mmu_pages, nr); @@ -2013,12 +2060,6 @@ static struct kvm_mmu_page *kvm_mmu_alloc_page(struct kvm_vcpu *vcpu, int direct if (!direct) sp->gfns = mmu_memory_cache_alloc(&vcpu->arch.mmu_page_cache); set_page_private(virt_to_page(sp->spt), (unsigned long)sp); - - /* - * The active_mmu_pages list is the FIFO list, do not move the - * page until it is zapped. kvm_zap_obsolete_pages depends on - * this feature. See the comments in kvm_zap_obsolete_pages(). - */ list_add(&sp->link, &vcpu->kvm->arch.active_mmu_pages); kvm_mod_used_mmu_pages(vcpu->kvm, +1); return sp; @@ -2159,35 +2200,33 @@ static void kvm_unlink_unsync_page(struct kvm *kvm, struct kvm_mmu_page *sp) --kvm->stat.mmu_unsync; } -static int kvm_mmu_prepare_zap_page(struct kvm *kvm, struct kvm_mmu_page *sp, - struct list_head *invalid_list); +static bool kvm_mmu_prepare_zap_page(struct kvm *kvm, struct kvm_mmu_page *sp, + struct list_head *invalid_list); static void kvm_mmu_commit_zap_page(struct kvm *kvm, struct list_head *invalid_list); -/* - * NOTE: we should pay more attention on the zapped-obsolete page - * (is_obsolete_sp(sp) && sp->role.invalid) when you do hash list walk - * since it has been deleted from active_mmu_pages but still can be found - * at hast list. - * - * for_each_valid_sp() has skipped that kind of pages. - */ + #define for_each_valid_sp(_kvm, _sp, _gfn) \ hlist_for_each_entry(_sp, \ &(_kvm)->arch.mmu_page_hash[kvm_page_table_hashfn(_gfn)], hash_link) \ - if (is_obsolete_sp((_kvm), (_sp)) || (_sp)->role.invalid) { \ + if ((_sp)->role.invalid) { \ } else #define for_each_gfn_indirect_valid_sp(_kvm, _sp, _gfn) \ for_each_valid_sp(_kvm, _sp, _gfn) \ if ((_sp)->gfn != (_gfn) || (_sp)->role.direct) {} else +static inline bool is_ept_sp(struct kvm_mmu_page *sp) +{ + return sp->role.cr0_wp && sp->role.smap_andnot_wp; +} + /* @sp->gfn should be write-protected at the call site */ static bool __kvm_sync_page(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp, struct list_head *invalid_list) { - if (sp->role.cr4_pae != !!is_pae(vcpu) - || vcpu->arch.mmu->sync_page(vcpu, sp) == 0) { + if ((!is_ept_sp(sp) && sp->role.gpte_is_8_bytes != !!is_pae(vcpu)) || + vcpu->arch.mmu->sync_page(vcpu, sp) == 0) { kvm_mmu_prepare_zap_page(vcpu->kvm, sp, invalid_list); return false; } @@ -2195,18 +2234,28 @@ static bool __kvm_sync_page(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp, return true; } +static bool kvm_mmu_remote_flush_or_zap(struct kvm *kvm, + struct list_head *invalid_list, + bool remote_flush) +{ + if (!remote_flush && list_empty(invalid_list)) + return false; + + if (!list_empty(invalid_list)) + kvm_mmu_commit_zap_page(kvm, invalid_list); + else + kvm_flush_remote_tlbs(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 (!list_empty(invalid_list)) { - kvm_mmu_commit_zap_page(vcpu->kvm, invalid_list); + if (kvm_mmu_remote_flush_or_zap(vcpu->kvm, invalid_list, remote_flush)) return; - } - if (remote_flush) - kvm_flush_remote_tlbs(vcpu->kvm); - else if (local_flush) + if (local_flush) kvm_make_request(KVM_REQ_TLB_FLUSH, vcpu); } @@ -2217,11 +2266,6 @@ static void kvm_mmu_audit(struct kvm_vcpu *vcpu, int point) { } static void mmu_audit_disable(void) { } #endif -static bool is_obsolete_sp(struct kvm *kvm, struct kvm_mmu_page *sp) -{ - return unlikely(sp->mmu_valid_gen != kvm->arch.mmu_valid_gen); -} - static bool kvm_sync_page(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp, struct list_head *invalid_list) { @@ -2385,7 +2429,7 @@ static struct kvm_mmu_page *kvm_mmu_get_page(struct kvm_vcpu *vcpu, role.level = level; role.direct = direct; if (role.direct) - role.cr4_pae = 0; + role.gpte_is_8_bytes = true; role.access = access; if (!vcpu->arch.mmu->direct_map && vcpu->arch.mmu->root_level <= PT32_ROOT_LEVEL) { @@ -2441,12 +2485,11 @@ static struct kvm_mmu_page *kvm_mmu_get_page(struct kvm_vcpu *vcpu, account_shadowed(vcpu->kvm, sp); if (level == PT_PAGE_TABLE_LEVEL && rmap_write_protect(vcpu, gfn)) - kvm_flush_remote_tlbs(vcpu->kvm); + kvm_flush_remote_tlbs_with_address(vcpu->kvm, gfn, 1); if (level > PT_PAGE_TABLE_LEVEL && need_sync) flush |= kvm_sync_pages(vcpu, gfn, &invalid_list); } - sp->mmu_valid_gen = vcpu->kvm->arch.mmu_valid_gen; clear_page(sp->spt); trace_kvm_mmu_get_page(sp, true); @@ -2561,7 +2604,7 @@ static void validate_direct_spte(struct kvm_vcpu *vcpu, u64 *sptep, return; drop_parent_pte(child, sptep); - kvm_flush_remote_tlbs(vcpu->kvm); + kvm_flush_remote_tlbs_with_address(vcpu->kvm, child->gfn, 1); } } @@ -2632,17 +2675,22 @@ static int mmu_zap_unsync_children(struct kvm *kvm, return zapped; } -static int kvm_mmu_prepare_zap_page(struct kvm *kvm, struct kvm_mmu_page *sp, - struct list_head *invalid_list) +static bool __kvm_mmu_prepare_zap_page(struct kvm *kvm, + struct kvm_mmu_page *sp, + struct list_head *invalid_list, + int *nr_zapped) { - int ret; + bool list_unstable; trace_kvm_mmu_prepare_zap_page(sp); ++kvm->stat.mmu_shadow_zapped; - ret = mmu_zap_unsync_children(kvm, sp, invalid_list); + *nr_zapped = mmu_zap_unsync_children(kvm, sp, invalid_list); kvm_mmu_page_unlink_children(kvm, sp); kvm_mmu_unlink_parents(kvm, sp); + /* Zapping children means active_mmu_pages has become unstable. */ + list_unstable = *nr_zapped; + if (!sp->role.invalid && !sp->role.direct) unaccount_shadowed(kvm, sp); @@ -2650,22 +2698,27 @@ static int kvm_mmu_prepare_zap_page(struct kvm *kvm, struct kvm_mmu_page *sp, kvm_unlink_unsync_page(kvm, sp); if (!sp->root_count) { /* Count self */ - ret++; + (*nr_zapped)++; list_move(&sp->link, invalid_list); kvm_mod_used_mmu_pages(kvm, -1); } else { list_move(&sp->link, &kvm->arch.active_mmu_pages); - /* - * The obsolete pages can not be used on any vcpus. - * See the comments in kvm_mmu_invalidate_zap_all_pages(). - */ - if (!sp->role.invalid && !is_obsolete_sp(kvm, sp)) + if (!sp->role.invalid) kvm_reload_remote_mmus(kvm); } sp->role.invalid = 1; - return ret; + return list_unstable; +} + +static bool kvm_mmu_prepare_zap_page(struct kvm *kvm, struct kvm_mmu_page *sp, + struct list_head *invalid_list) +{ + int nr_zapped; + + __kvm_mmu_prepare_zap_page(kvm, sp, invalid_list, &nr_zapped); + return nr_zapped; } static void kvm_mmu_commit_zap_page(struct kvm *kvm, @@ -2710,7 +2763,7 @@ static bool prepare_zap_oldest_mmu_page(struct kvm *kvm, * Changing the number of mmu pages allocated to the vm * Note: if goal_nr_mmu_pages is too small, you will get dead lock */ -void kvm_mmu_change_mmu_pages(struct kvm *kvm, unsigned int goal_nr_mmu_pages) +void kvm_mmu_change_mmu_pages(struct kvm *kvm, unsigned long goal_nr_mmu_pages) { LIST_HEAD(invalid_list); @@ -2985,8 +3038,10 @@ static int mmu_set_spte(struct kvm_vcpu *vcpu, u64 *sptep, unsigned pte_access, ret = RET_PF_EMULATE; kvm_make_request(KVM_REQ_TLB_FLUSH, vcpu); } + if (set_spte_ret & SET_SPTE_NEED_REMOTE_TLB_FLUSH || flush) - kvm_flush_remote_tlbs(vcpu->kvm); + kvm_flush_remote_tlbs_with_address(vcpu->kvm, gfn, + KVM_PAGES_PER_HPAGE(level)); if (unlikely(is_mmio_spte(*sptep))) ret = RET_PF_EMULATE; @@ -3517,6 +3572,7 @@ void kvm_mmu_free_roots(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu, &invalid_list); mmu->root_hpa = INVALID_PAGE; } + mmu->root_cr3 = 0; } kvm_mmu_commit_zap_page(vcpu->kvm, &invalid_list); @@ -3572,6 +3628,7 @@ static int mmu_alloc_direct_roots(struct kvm_vcpu *vcpu) vcpu->arch.mmu->root_hpa = __pa(vcpu->arch.mmu->pae_root); } else BUG(); + vcpu->arch.mmu->root_cr3 = vcpu->arch.mmu->get_cr3(vcpu); return 0; } @@ -3580,10 +3637,11 @@ static int mmu_alloc_shadow_roots(struct kvm_vcpu *vcpu) { struct kvm_mmu_page *sp; u64 pdptr, pm_mask; - gfn_t root_gfn; + gfn_t root_gfn, root_cr3; int i; - root_gfn = vcpu->arch.mmu->get_cr3(vcpu) >> PAGE_SHIFT; + root_cr3 = vcpu->arch.mmu->get_cr3(vcpu); + root_gfn = root_cr3 >> PAGE_SHIFT; if (mmu_check_root(vcpu, root_gfn)) return 1; @@ -3608,7 +3666,7 @@ static int mmu_alloc_shadow_roots(struct kvm_vcpu *vcpu) ++sp->root_count; spin_unlock(&vcpu->kvm->mmu_lock); vcpu->arch.mmu->root_hpa = root; - return 0; + goto set_root_cr3; } /* @@ -3662,7 +3720,7 @@ static int mmu_alloc_shadow_roots(struct kvm_vcpu *vcpu) u64 *lm_root; - lm_root = (void*)get_zeroed_page(GFP_KERNEL); + lm_root = (void*)get_zeroed_page(GFP_KERNEL_ACCOUNT); if (lm_root == NULL) return 1; @@ -3674,6 +3732,9 @@ static int mmu_alloc_shadow_roots(struct kvm_vcpu *vcpu) vcpu->arch.mmu->root_hpa = __pa(vcpu->arch.mmu->lm_root); } +set_root_cr3: + vcpu->arch.mmu->root_cr3 = root_cr3; + return 0; } @@ -4125,7 +4186,7 @@ static bool cached_root_available(struct kvm_vcpu *vcpu, gpa_t new_cr3, struct kvm_mmu_root_info root; struct kvm_mmu *mmu = vcpu->arch.mmu; - root.cr3 = mmu->get_cr3(vcpu); + root.cr3 = mmu->root_cr3; root.hpa = mmu->root_hpa; for (i = 0; i < KVM_MMU_NUM_PREV_ROOTS; i++) { @@ -4138,6 +4199,7 @@ static bool cached_root_available(struct kvm_vcpu *vcpu, gpa_t new_cr3, } mmu->root_hpa = root.hpa; + mmu->root_cr3 = root.cr3; return i < KVM_MMU_NUM_PREV_ROOTS; } @@ -4159,14 +4221,6 @@ static bool fast_cr3_switch(struct kvm_vcpu *vcpu, gpa_t new_cr3, return false; if (cached_root_available(vcpu, new_cr3, new_role)) { - /* - * It is possible that the cached previous root page is - * obsolete because of a change in the MMU - * generation number. However, that is accompanied by - * KVM_REQ_MMU_RELOAD, which will free the root that we - * have set here and allocate a new one. - */ - kvm_make_request(KVM_REQ_LOAD_CR3, vcpu); if (!skip_tlb_flush) { kvm_make_request(KVM_REQ_MMU_SYNC, vcpu); @@ -4333,6 +4387,7 @@ __reset_rsvds_bits_mask(struct kvm_vcpu *vcpu, rsvd_bits(maxphyaddr, 51); rsvd_check->rsvd_bits_mask[1][4] = rsvd_check->rsvd_bits_mask[0][4]; + /* fall through */ case PT64_ROOT_4LEVEL: rsvd_check->rsvd_bits_mask[0][3] = exb_bit_rsvd | nonleaf_bit8_rsvd | rsvd_bits(7, 7) | @@ -4726,11 +4781,13 @@ static union kvm_mmu_extended_role kvm_calc_mmu_role_ext(struct kvm_vcpu *vcpu) union kvm_mmu_extended_role ext = {0}; ext.cr0_pg = !!is_paging(vcpu); + ext.cr4_pae = !!is_pae(vcpu); ext.cr4_smep = !!kvm_read_cr4_bits(vcpu, X86_CR4_SMEP); ext.cr4_smap = !!kvm_read_cr4_bits(vcpu, X86_CR4_SMAP); ext.cr4_pse = !!is_pse(vcpu); ext.cr4_pke = !!kvm_read_cr4_bits(vcpu, X86_CR4_PKE); ext.cr4_la57 = !!kvm_read_cr4_bits(vcpu, X86_CR4_LA57); + ext.maxphyaddr = cpuid_maxphyaddr(vcpu); ext.valid = 1; @@ -4744,7 +4801,6 @@ static union kvm_mmu_role kvm_calc_mmu_role_common(struct kvm_vcpu *vcpu, role.base.access = ACC_ALL; role.base.nxe = !!is_nx(vcpu); - role.base.cr4_pae = !!is_pae(vcpu); role.base.cr0_wp = is_write_protection(vcpu); role.base.smm = is_smm(vcpu); role.base.guest_mode = is_guest_mode(vcpu); @@ -4765,6 +4821,7 @@ kvm_calc_tdp_mmu_root_page_role(struct kvm_vcpu *vcpu, bool base_only) role.base.ad_disabled = (shadow_accessed_mask == 0); role.base.level = kvm_x86_ops->get_tdp_level(vcpu); role.base.direct = true; + role.base.gpte_is_8_bytes = true; return role; } @@ -4829,6 +4886,7 @@ kvm_calc_shadow_mmu_root_page_role(struct kvm_vcpu *vcpu, bool base_only) role.base.smap_andnot_wp = role.ext.cr4_smap && !is_write_protection(vcpu); role.base.direct = !is_paging(vcpu); + role.base.gpte_is_8_bytes = !!is_pae(vcpu); if (!is_long_mode(vcpu)) role.base.level = PT32E_ROOT_LEVEL; @@ -4868,18 +4926,26 @@ static union kvm_mmu_role kvm_calc_shadow_ept_root_page_role(struct kvm_vcpu *vcpu, bool accessed_dirty, bool execonly) { - union kvm_mmu_role role; + union kvm_mmu_role role = {0}; - /* Base role is inherited from root_mmu */ - role.base.word = vcpu->arch.root_mmu.mmu_role.base.word; - role.ext = kvm_calc_mmu_role_ext(vcpu); + /* SMM flag is inherited from root_mmu */ + role.base.smm = vcpu->arch.root_mmu.mmu_role.base.smm; role.base.level = PT64_ROOT_4LEVEL; + role.base.gpte_is_8_bytes = true; role.base.direct = false; role.base.ad_disabled = !accessed_dirty; role.base.guest_mode = true; role.base.access = ACC_ALL; + /* + * WP=1 and NOT_WP=1 is an impossible combination, use WP and the + * SMAP variation to denote shadow EPT entries. + */ + role.base.cr0_wp = true; + role.base.smap_andnot_wp = true; + + role.ext = kvm_calc_mmu_role_ext(vcpu); role.ext.execonly = execonly; return role; @@ -5129,7 +5195,7 @@ static bool detect_write_misaligned(struct kvm_mmu_page *sp, gpa_t gpa, gpa, bytes, sp->role.word); offset = offset_in_page(gpa); - pte_size = sp->role.cr4_pae ? 8 : 4; + pte_size = sp->role.gpte_is_8_bytes ? 8 : 4; /* * Sometimes, the OS only writes the last one bytes to update status @@ -5153,7 +5219,7 @@ static u64 *get_written_sptes(struct kvm_mmu_page *sp, gpa_t gpa, int *nspte) page_offset = offset_in_page(gpa); level = sp->role.level; *nspte = 1; - if (!sp->role.cr4_pae) { + if (!sp->role.gpte_is_8_bytes) { page_offset <<= 1; /* 32->64 */ /* * A 32-bit pde maps 4MB while the shadow pdes map @@ -5343,10 +5409,12 @@ emulate: * This can happen if a guest gets a page-fault on data access but the HW * table walker is not able to read the instruction page (e.g instruction * page is not present in memory). In those cases we simply restart the - * guest. + * guest, with the exception of AMD Erratum 1096 which is unrecoverable. */ - if (unlikely(insn && !insn_len)) - return 1; + if (unlikely(insn && !insn_len)) { + if (!kvm_x86_ops->need_emulation_on_page_fault(vcpu)) + return 1; + } er = x86_emulate_instruction(vcpu, cr2, emulation_type, insn, insn_len); @@ -5439,6 +5507,79 @@ void kvm_disable_tdp(void) } EXPORT_SYMBOL_GPL(kvm_disable_tdp); + +/* The return value indicates if tlb flush on all vcpus is needed. */ +typedef bool (*slot_level_handler) (struct kvm *kvm, struct kvm_rmap_head *rmap_head); + +/* The caller should hold mmu-lock before calling this function. */ +static __always_inline bool +slot_handle_level_range(struct kvm *kvm, struct kvm_memory_slot *memslot, + slot_level_handler fn, int start_level, int end_level, + gfn_t start_gfn, gfn_t end_gfn, bool lock_flush_tlb) +{ + struct slot_rmap_walk_iterator iterator; + bool flush = false; + + for_each_slot_rmap_range(memslot, start_level, end_level, start_gfn, + end_gfn, &iterator) { + if (iterator.rmap) + flush |= fn(kvm, iterator.rmap); + + if (need_resched() || spin_needbreak(&kvm->mmu_lock)) { + if (flush && lock_flush_tlb) { + kvm_flush_remote_tlbs_with_address(kvm, + start_gfn, + iterator.gfn - start_gfn + 1); + flush = false; + } + cond_resched_lock(&kvm->mmu_lock); + } + } + + if (flush && lock_flush_tlb) { + kvm_flush_remote_tlbs_with_address(kvm, start_gfn, + end_gfn - start_gfn + 1); + flush = false; + } + + return flush; +} + +static __always_inline bool +slot_handle_level(struct kvm *kvm, struct kvm_memory_slot *memslot, + slot_level_handler fn, int start_level, int end_level, + bool lock_flush_tlb) +{ + return slot_handle_level_range(kvm, memslot, fn, start_level, + end_level, memslot->base_gfn, + memslot->base_gfn + memslot->npages - 1, + lock_flush_tlb); +} + +static __always_inline bool +slot_handle_all_level(struct kvm *kvm, struct kvm_memory_slot *memslot, + slot_level_handler fn, bool lock_flush_tlb) +{ + return slot_handle_level(kvm, memslot, fn, PT_PAGE_TABLE_LEVEL, + PT_MAX_HUGEPAGE_LEVEL, lock_flush_tlb); +} + +static __always_inline bool +slot_handle_large_level(struct kvm *kvm, struct kvm_memory_slot *memslot, + slot_level_handler fn, bool lock_flush_tlb) +{ + return slot_handle_level(kvm, memslot, fn, PT_PAGE_TABLE_LEVEL + 1, + PT_MAX_HUGEPAGE_LEVEL, lock_flush_tlb); +} + +static __always_inline bool +slot_handle_leaf(struct kvm *kvm, struct kvm_memory_slot *memslot, + slot_level_handler fn, bool lock_flush_tlb) +{ + return slot_handle_level(kvm, memslot, fn, PT_PAGE_TABLE_LEVEL, + PT_PAGE_TABLE_LEVEL, lock_flush_tlb); +} + static void free_mmu_pages(struct kvm_vcpu *vcpu) { free_page((unsigned long)vcpu->arch.mmu->pae_root); @@ -5458,7 +5599,7 @@ static int alloc_mmu_pages(struct kvm_vcpu *vcpu) * Therefore we need to allocate shadow page tables in the first * 4GB of memory, which happens to fit the DMA32 zone. */ - page = alloc_page(GFP_KERNEL | __GFP_DMA32); + page = alloc_page(GFP_KERNEL_ACCOUNT | __GFP_DMA32); if (!page) return -ENOMEM; @@ -5477,11 +5618,13 @@ int kvm_mmu_create(struct kvm_vcpu *vcpu) vcpu->arch.walk_mmu = &vcpu->arch.root_mmu; vcpu->arch.root_mmu.root_hpa = INVALID_PAGE; + vcpu->arch.root_mmu.root_cr3 = 0; vcpu->arch.root_mmu.translate_gpa = translate_gpa; for (i = 0; i < KVM_MMU_NUM_PREV_ROOTS; i++) vcpu->arch.root_mmu.prev_roots[i] = KVM_MMU_ROOT_INFO_INVALID; vcpu->arch.guest_mmu.root_hpa = INVALID_PAGE; + vcpu->arch.guest_mmu.root_cr3 = 0; vcpu->arch.guest_mmu.translate_gpa = translate_gpa; for (i = 0; i < KVM_MMU_NUM_PREV_ROOTS; i++) vcpu->arch.guest_mmu.prev_roots[i] = KVM_MMU_ROOT_INFO_INVALID; @@ -5494,92 +5637,54 @@ static void kvm_mmu_invalidate_zap_pages_in_memslot(struct kvm *kvm, struct kvm_memory_slot *slot, struct kvm_page_track_notifier_node *node) { - kvm_mmu_invalidate_zap_all_pages(kvm); -} - -void kvm_mmu_init_vm(struct kvm *kvm) -{ - struct kvm_page_track_notifier_node *node = &kvm->arch.mmu_sp_tracker; + struct kvm_mmu_page *sp; + LIST_HEAD(invalid_list); + unsigned long i; + bool flush; + gfn_t gfn; - node->track_write = kvm_mmu_pte_write; - node->track_flush_slot = kvm_mmu_invalidate_zap_pages_in_memslot; - kvm_page_track_register_notifier(kvm, node); -} + spin_lock(&kvm->mmu_lock); -void kvm_mmu_uninit_vm(struct kvm *kvm) -{ - struct kvm_page_track_notifier_node *node = &kvm->arch.mmu_sp_tracker; + if (list_empty(&kvm->arch.active_mmu_pages)) + goto out_unlock; - kvm_page_track_unregister_notifier(kvm, node); -} + flush = slot_handle_all_level(kvm, slot, kvm_zap_rmapp, false); -/* The return value indicates if tlb flush on all vcpus is needed. */ -typedef bool (*slot_level_handler) (struct kvm *kvm, struct kvm_rmap_head *rmap_head); + for (i = 0; i < slot->npages; i++) { + gfn = slot->base_gfn + i; -/* The caller should hold mmu-lock before calling this function. */ -static __always_inline bool -slot_handle_level_range(struct kvm *kvm, struct kvm_memory_slot *memslot, - slot_level_handler fn, int start_level, int end_level, - gfn_t start_gfn, gfn_t end_gfn, bool lock_flush_tlb) -{ - struct slot_rmap_walk_iterator iterator; - bool flush = false; - - for_each_slot_rmap_range(memslot, start_level, end_level, start_gfn, - end_gfn, &iterator) { - if (iterator.rmap) - flush |= fn(kvm, iterator.rmap); + for_each_valid_sp(kvm, sp, gfn) { + if (sp->gfn != gfn) + continue; + kvm_mmu_prepare_zap_page(kvm, sp, &invalid_list); + } if (need_resched() || spin_needbreak(&kvm->mmu_lock)) { - if (flush && lock_flush_tlb) { - kvm_flush_remote_tlbs(kvm); - flush = false; - } + kvm_mmu_remote_flush_or_zap(kvm, &invalid_list, flush); + flush = false; cond_resched_lock(&kvm->mmu_lock); } } + kvm_mmu_remote_flush_or_zap(kvm, &invalid_list, flush); - if (flush && lock_flush_tlb) { - kvm_flush_remote_tlbs(kvm); - flush = false; - } - - return flush; +out_unlock: + spin_unlock(&kvm->mmu_lock); } -static __always_inline bool -slot_handle_level(struct kvm *kvm, struct kvm_memory_slot *memslot, - slot_level_handler fn, int start_level, int end_level, - bool lock_flush_tlb) +void kvm_mmu_init_vm(struct kvm *kvm) { - return slot_handle_level_range(kvm, memslot, fn, start_level, - end_level, memslot->base_gfn, - memslot->base_gfn + memslot->npages - 1, - lock_flush_tlb); -} + struct kvm_page_track_notifier_node *node = &kvm->arch.mmu_sp_tracker; -static __always_inline bool -slot_handle_all_level(struct kvm *kvm, struct kvm_memory_slot *memslot, - slot_level_handler fn, bool lock_flush_tlb) -{ - return slot_handle_level(kvm, memslot, fn, PT_PAGE_TABLE_LEVEL, - PT_MAX_HUGEPAGE_LEVEL, lock_flush_tlb); + node->track_write = kvm_mmu_pte_write; + node->track_flush_slot = kvm_mmu_invalidate_zap_pages_in_memslot; + kvm_page_track_register_notifier(kvm, node); } -static __always_inline bool -slot_handle_large_level(struct kvm *kvm, struct kvm_memory_slot *memslot, - slot_level_handler fn, bool lock_flush_tlb) +void kvm_mmu_uninit_vm(struct kvm *kvm) { - return slot_handle_level(kvm, memslot, fn, PT_PAGE_TABLE_LEVEL + 1, - PT_MAX_HUGEPAGE_LEVEL, lock_flush_tlb); -} + struct kvm_page_track_notifier_node *node = &kvm->arch.mmu_sp_tracker; -static __always_inline bool -slot_handle_leaf(struct kvm *kvm, struct kvm_memory_slot *memslot, - slot_level_handler fn, bool lock_flush_tlb) -{ - return slot_handle_level(kvm, memslot, fn, PT_PAGE_TABLE_LEVEL, - PT_PAGE_TABLE_LEVEL, lock_flush_tlb); + kvm_page_track_unregister_notifier(kvm, node); } void kvm_zap_gfn_range(struct kvm *kvm, gfn_t gfn_start, gfn_t gfn_end) @@ -5638,12 +5743,13 @@ void kvm_mmu_slot_remove_write_access(struct kvm *kvm, * spte from present to present (changing the spte from present * to nonpresent will flush all the TLBs immediately), in other * words, the only case we care is mmu_spte_update() where we - * haved checked SPTE_HOST_WRITEABLE | SPTE_MMU_WRITEABLE + * have checked SPTE_HOST_WRITEABLE | SPTE_MMU_WRITEABLE * instead of PT_WRITABLE_MASK, that means it does not depend * on PT_WRITABLE_MASK anymore. */ if (flush) - kvm_flush_remote_tlbs(kvm); + kvm_flush_remote_tlbs_with_address(kvm, memslot->base_gfn, + memslot->npages); } static bool kvm_mmu_zap_collapsible_spte(struct kvm *kvm, @@ -5671,7 +5777,13 @@ restart: !kvm_is_reserved_pfn(pfn) && PageTransCompoundMap(pfn_to_page(pfn))) { pte_list_remove(rmap_head, sptep); - need_tlb_flush = 1; + + if (kvm_available_flush_tlb_with_range()) + kvm_flush_remote_tlbs_with_address(kvm, sp->gfn, + KVM_PAGES_PER_HPAGE(sp->role.level)); + else + need_tlb_flush = 1; + goto restart; } } @@ -5707,7 +5819,8 @@ void kvm_mmu_slot_leaf_clear_dirty(struct kvm *kvm, * dirty_bitmap. */ if (flush) - kvm_flush_remote_tlbs(kvm); + kvm_flush_remote_tlbs_with_address(kvm, memslot->base_gfn, + memslot->npages); } EXPORT_SYMBOL_GPL(kvm_mmu_slot_leaf_clear_dirty); @@ -5725,7 +5838,8 @@ void kvm_mmu_slot_largepage_remove_write_access(struct kvm *kvm, lockdep_assert_held(&kvm->slots_lock); if (flush) - kvm_flush_remote_tlbs(kvm); + kvm_flush_remote_tlbs_with_address(kvm, memslot->base_gfn, + memslot->npages); } EXPORT_SYMBOL_GPL(kvm_mmu_slot_largepage_remove_write_access); @@ -5742,105 +5856,63 @@ void kvm_mmu_slot_set_dirty(struct kvm *kvm, /* see kvm_mmu_slot_leaf_clear_dirty */ if (flush) - kvm_flush_remote_tlbs(kvm); + kvm_flush_remote_tlbs_with_address(kvm, memslot->base_gfn, + memslot->npages); } EXPORT_SYMBOL_GPL(kvm_mmu_slot_set_dirty); -#define BATCH_ZAP_PAGES 10 -static void kvm_zap_obsolete_pages(struct kvm *kvm) +static void __kvm_mmu_zap_all(struct kvm *kvm, bool mmio_only) { struct kvm_mmu_page *sp, *node; - int batch = 0; + LIST_HEAD(invalid_list); + int ign; + spin_lock(&kvm->mmu_lock); restart: - list_for_each_entry_safe_reverse(sp, node, - &kvm->arch.active_mmu_pages, link) { - int ret; - - /* - * No obsolete page exists before new created page since - * active_mmu_pages is the FIFO list. - */ - if (!is_obsolete_sp(kvm, sp)) - break; - - /* - * Since we are reversely walking the list and the invalid - * list will be moved to the head, skip the invalid page - * can help us to avoid the infinity list walking. - */ - if (sp->role.invalid) + list_for_each_entry_safe(sp, node, &kvm->arch.active_mmu_pages, link) { + if (mmio_only && !sp->mmio_cached) continue; - - /* - * Need not flush tlb since we only zap the sp with invalid - * generation number. - */ - if (batch >= BATCH_ZAP_PAGES && - cond_resched_lock(&kvm->mmu_lock)) { - batch = 0; + if (sp->role.invalid && sp->root_count) + continue; + if (__kvm_mmu_prepare_zap_page(kvm, sp, &invalid_list, &ign)) { + WARN_ON_ONCE(mmio_only); goto restart; } - - ret = kvm_mmu_prepare_zap_page(kvm, sp, - &kvm->arch.zapped_obsolete_pages); - batch += ret; - - if (ret) + if (cond_resched_lock(&kvm->mmu_lock)) goto restart; } - /* - * Should flush tlb before free page tables since lockless-walking - * may use the pages. - */ - kvm_mmu_commit_zap_page(kvm, &kvm->arch.zapped_obsolete_pages); -} - -/* - * Fast invalidate all shadow pages and use lock-break technique - * to zap obsolete pages. - * - * It's required when memslot is being deleted or VM is being - * destroyed, in these cases, we should ensure that KVM MMU does - * not use any resource of the being-deleted slot or all slots - * after calling the function. - */ -void kvm_mmu_invalidate_zap_all_pages(struct kvm *kvm) -{ - spin_lock(&kvm->mmu_lock); - trace_kvm_mmu_invalidate_zap_all_pages(kvm); - kvm->arch.mmu_valid_gen++; - - /* - * Notify all vcpus to reload its shadow page table - * and flush TLB. Then all vcpus will switch to new - * shadow page table with the new mmu_valid_gen. - * - * Note: we should do this under the protection of - * mmu-lock, otherwise, vcpu would purge shadow page - * but miss tlb flush. - */ - kvm_reload_remote_mmus(kvm); - - kvm_zap_obsolete_pages(kvm); + kvm_mmu_commit_zap_page(kvm, &invalid_list); spin_unlock(&kvm->mmu_lock); } -static bool kvm_has_zapped_obsolete_pages(struct kvm *kvm) +void kvm_mmu_zap_all(struct kvm *kvm) { - return unlikely(!list_empty_careful(&kvm->arch.zapped_obsolete_pages)); + return __kvm_mmu_zap_all(kvm, false); } -void kvm_mmu_invalidate_mmio_sptes(struct kvm *kvm, struct kvm_memslots *slots) +void kvm_mmu_invalidate_mmio_sptes(struct kvm *kvm, u64 gen) { + WARN_ON(gen & KVM_MEMSLOT_GEN_UPDATE_IN_PROGRESS); + + gen &= MMIO_SPTE_GEN_MASK; + + /* + * Generation numbers are incremented in multiples of the number of + * address spaces in order to provide unique generations across all + * address spaces. Strip what is effectively the address space + * modifier prior to checking for a wrap of the MMIO generation so + * that a wrap in any address space is detected. + */ + gen &= ~((u64)KVM_ADDRESS_SPACE_NUM - 1); + /* - * The very rare case: if the generation-number is round, + * The very rare case: if the MMIO generation number has wrapped, * zap all shadow pages. */ - if (unlikely((slots->generation & MMIO_GEN_MASK) == 0)) { + if (unlikely(gen == 0)) { kvm_debug_ratelimited("kvm: zapping shadow pages for mmio generation wraparound\n"); - kvm_mmu_invalidate_zap_all_pages(kvm); + __kvm_mmu_zap_all(kvm, true); } } @@ -5871,24 +5943,16 @@ mmu_shrink_scan(struct shrinker *shrink, struct shrink_control *sc) * want to shrink a VM that only started to populate its MMU * anyway. */ - if (!kvm->arch.n_used_mmu_pages && - !kvm_has_zapped_obsolete_pages(kvm)) + if (!kvm->arch.n_used_mmu_pages) continue; idx = srcu_read_lock(&kvm->srcu); spin_lock(&kvm->mmu_lock); - if (kvm_has_zapped_obsolete_pages(kvm)) { - kvm_mmu_commit_zap_page(kvm, - &kvm->arch.zapped_obsolete_pages); - goto unlock; - } - if (prepare_zap_oldest_mmu_page(kvm, &invalid_list)) freed++; kvm_mmu_commit_zap_page(kvm, &invalid_list); -unlock: spin_unlock(&kvm->mmu_lock); srcu_read_unlock(&kvm->srcu, idx); @@ -5968,10 +6032,10 @@ out: /* * Calculate mmu pages needed for kvm. */ -unsigned int kvm_mmu_calculate_mmu_pages(struct kvm *kvm) +unsigned long kvm_mmu_calculate_default_mmu_pages(struct kvm *kvm) { - unsigned int nr_mmu_pages; - unsigned int nr_pages = 0; + unsigned long nr_mmu_pages; + unsigned long nr_pages = 0; struct kvm_memslots *slots; struct kvm_memory_slot *memslot; int i; @@ -5984,8 +6048,7 @@ unsigned int kvm_mmu_calculate_mmu_pages(struct kvm *kvm) } nr_mmu_pages = nr_pages * KVM_PERMILLE_MMU_PAGES / 1000; - nr_mmu_pages = max(nr_mmu_pages, - (unsigned int) KVM_MIN_ALLOC_MMU_PAGES); + nr_mmu_pages = max(nr_mmu_pages, KVM_MIN_ALLOC_MMU_PAGES); return nr_mmu_pages; } |