diff options
| -rw-r--r-- | Documentation/admin-guide/kernel-parameters.txt | 4 | ||||
| -rw-r--r-- | arch/x86/include/asm/kvm_host.h | 4 | ||||
| -rw-r--r-- | arch/x86/kvm/Kconfig | 7 | ||||
| -rw-r--r-- | arch/x86/kvm/mmu/mmu.c | 25 | ||||
| -rw-r--r-- | arch/x86/kvm/mmu/mmu_audit.c | 303 | ||||
| -rw-r--r-- | arch/x86/kvm/mmu/paging_tmpl.h | 2 |
6 files changed, 0 insertions, 345 deletions
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 2a9746fe6c4a..05161afd7642 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -2368,10 +2368,6 @@ kvm.enable_vmware_backdoor=[KVM] Support VMware backdoor PV interface. Default is false (don't support). - kvm.mmu_audit= [KVM] This is a R/W parameter which allows audit - KVM MMU at runtime. - Default is 0 (off) - kvm.nx_huge_pages= [KVM] Controls the software workaround for the X86_BUG_ITLB_MULTIHIT bug. diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 8e512f25a930..884c926e4359 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -1128,10 +1128,6 @@ struct kvm_arch { struct kvm_hv hyperv; struct kvm_xen xen; - #ifdef CONFIG_KVM_MMU_AUDIT - int audit_point; - #endif - bool backwards_tsc_observed; bool boot_vcpu_runs_old_kvmclock; u32 bsp_vcpu_id; diff --git a/arch/x86/kvm/Kconfig b/arch/x86/kvm/Kconfig index 2b1548da00eb..e3cbd7706136 100644 --- a/arch/x86/kvm/Kconfig +++ b/arch/x86/kvm/Kconfig @@ -126,13 +126,6 @@ config KVM_XEN If in doubt, say "N". -config KVM_MMU_AUDIT - bool "Audit KVM MMU" - depends on KVM && TRACEPOINTS - help - This option adds a R/W kVM module parameter 'mmu_audit', which allows - auditing of KVM MMU events at runtime. - config KVM_EXTERNAL_WRITE_TRACKING bool diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c index 296f8723f9ae..0620480b99e0 100644 --- a/arch/x86/kvm/mmu/mmu.c +++ b/arch/x86/kvm/mmu/mmu.c @@ -104,15 +104,6 @@ static int max_huge_page_level __read_mostly; static int tdp_root_level __read_mostly; static int max_tdp_level __read_mostly; -enum { - AUDIT_PRE_PAGE_FAULT, - AUDIT_POST_PAGE_FAULT, - AUDIT_PRE_PTE_WRITE, - AUDIT_POST_PTE_WRITE, - AUDIT_PRE_SYNC, - AUDIT_POST_SYNC -}; - #ifdef MMU_DEBUG bool dbg = 0; module_param(dbg, bool, 0644); @@ -1904,13 +1895,6 @@ static bool kvm_mmu_remote_flush_or_zap(struct kvm *kvm, return true; } -#ifdef CONFIG_KVM_MMU_AUDIT -#include "mmu_audit.c" -#else -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) { if (sp->role.invalid) @@ -3670,17 +3654,12 @@ void kvm_mmu_sync_roots(struct kvm_vcpu *vcpu) return; write_lock(&vcpu->kvm->mmu_lock); - kvm_mmu_audit(vcpu, AUDIT_PRE_SYNC); - mmu_sync_children(vcpu, sp, true); - - kvm_mmu_audit(vcpu, AUDIT_POST_SYNC); write_unlock(&vcpu->kvm->mmu_lock); return; } write_lock(&vcpu->kvm->mmu_lock); - kvm_mmu_audit(vcpu, AUDIT_PRE_SYNC); for (i = 0; i < 4; ++i) { hpa_t root = vcpu->arch.mmu->pae_root[i]; @@ -3692,7 +3671,6 @@ void kvm_mmu_sync_roots(struct kvm_vcpu *vcpu) } } - kvm_mmu_audit(vcpu, AUDIT_POST_SYNC); write_unlock(&vcpu->kvm->mmu_lock); } @@ -5241,7 +5219,6 @@ static void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa, gentry = mmu_pte_write_fetch_gpte(vcpu, &gpa, &bytes); ++vcpu->kvm->stat.mmu_pte_write; - kvm_mmu_audit(vcpu, AUDIT_PRE_PTE_WRITE); for_each_gfn_indirect_valid_sp(vcpu->kvm, sp, gfn) { if (detect_write_misaligned(sp, gpa, bytes) || @@ -5266,7 +5243,6 @@ static void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa, } } 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); } @@ -6212,7 +6188,6 @@ void kvm_mmu_module_exit(void) mmu_destroy_caches(); percpu_counter_destroy(&kvm_total_used_mmu_pages); unregister_shrinker(&mmu_shrinker); - mmu_audit_disable(); } /* diff --git a/arch/x86/kvm/mmu/mmu_audit.c b/arch/x86/kvm/mmu/mmu_audit.c deleted file mode 100644 index f31fdb874f1f..000000000000 --- a/arch/x86/kvm/mmu/mmu_audit.c +++ /dev/null @@ -1,303 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-only -/* - * mmu_audit.c: - * - * Audit code for KVM MMU - * - * Copyright (C) 2006 Qumranet, Inc. - * Copyright 2010 Red Hat, Inc. and/or its affiliates. - * - * Authors: - * Yaniv Kamay <[email protected]> - * Avi Kivity <[email protected]> - * Marcelo Tosatti <[email protected]> - * Xiao Guangrong <[email protected]> - */ - -#include <linux/ratelimit.h> - -static char const *audit_point_name[] = { - "pre page fault", - "post page fault", - "pre pte write", - "post pte write", - "pre sync", - "post sync" -}; - -#define audit_printk(kvm, fmt, args...) \ - printk(KERN_ERR "audit: (%s) error: " \ - fmt, audit_point_name[kvm->arch.audit_point], ##args) - -typedef void (*inspect_spte_fn) (struct kvm_vcpu *vcpu, u64 *sptep, int level); - -static void __mmu_spte_walk(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp, - inspect_spte_fn fn, int level) -{ - int i; - - for (i = 0; i < PT64_ENT_PER_PAGE; ++i) { - u64 *ent = sp->spt; - - fn(vcpu, ent + i, level); - - if (is_shadow_present_pte(ent[i]) && - !is_last_spte(ent[i], level)) { - struct kvm_mmu_page *child; - - child = to_shadow_page(ent[i] & PT64_BASE_ADDR_MASK); - __mmu_spte_walk(vcpu, child, fn, level - 1); - } - } -} - -static void mmu_spte_walk(struct kvm_vcpu *vcpu, inspect_spte_fn fn) -{ - int i; - struct kvm_mmu_page *sp; - - if (!VALID_PAGE(vcpu->arch.mmu->root_hpa)) - return; - - if (vcpu->arch.mmu->root_level >= PT64_ROOT_4LEVEL) { - hpa_t root = vcpu->arch.mmu->root_hpa; - - sp = to_shadow_page(root); - __mmu_spte_walk(vcpu, sp, fn, vcpu->arch.mmu->root_level); - return; - } - - for (i = 0; i < 4; ++i) { - hpa_t root = vcpu->arch.mmu->pae_root[i]; - - if (IS_VALID_PAE_ROOT(root)) { - root &= PT64_BASE_ADDR_MASK; - sp = to_shadow_page(root); - __mmu_spte_walk(vcpu, sp, fn, 2); - } - } - - return; -} - -typedef void (*sp_handler) (struct kvm *kvm, struct kvm_mmu_page *sp); - -static void walk_all_active_sps(struct kvm *kvm, sp_handler fn) -{ - struct kvm_mmu_page *sp; - - list_for_each_entry(sp, &kvm->arch.active_mmu_pages, link) - fn(kvm, sp); -} - -static void audit_mappings(struct kvm_vcpu *vcpu, u64 *sptep, int level) -{ - struct kvm_mmu_page *sp; - gfn_t gfn; - kvm_pfn_t pfn; - hpa_t hpa; - - sp = sptep_to_sp(sptep); - - if (sp->unsync) { - if (level != PG_LEVEL_4K) { - audit_printk(vcpu->kvm, "unsync sp: %p " - "level = %d\n", sp, level); - return; - } - } - - if (!is_shadow_present_pte(*sptep) || !is_last_spte(*sptep, level)) - return; - - gfn = kvm_mmu_page_get_gfn(sp, sptep - sp->spt); - pfn = kvm_vcpu_gfn_to_pfn_atomic(vcpu, gfn); - - if (is_error_pfn(pfn)) - return; - - hpa = pfn << PAGE_SHIFT; - if ((*sptep & PT64_BASE_ADDR_MASK) != hpa) - audit_printk(vcpu->kvm, "levels %d pfn %llx hpa %llx " - "ent %llxn", vcpu->arch.mmu->root_level, pfn, - hpa, *sptep); -} - -static void inspect_spte_has_rmap(struct kvm *kvm, u64 *sptep) -{ - static DEFINE_RATELIMIT_STATE(ratelimit_state, 5 * HZ, 10); - struct kvm_rmap_head *rmap_head; - struct kvm_mmu_page *rev_sp; - struct kvm_memslots *slots; - struct kvm_memory_slot *slot; - gfn_t gfn; - - rev_sp = sptep_to_sp(sptep); - gfn = kvm_mmu_page_get_gfn(rev_sp, sptep - rev_sp->spt); - - slots = kvm_memslots_for_spte_role(kvm, rev_sp->role); - slot = __gfn_to_memslot(slots, gfn); - if (!slot) { - if (!__ratelimit(&ratelimit_state)) - return; - audit_printk(kvm, "no memslot for gfn %llx\n", gfn); - audit_printk(kvm, "index %ld of sp (gfn=%llx)\n", - (long int)(sptep - rev_sp->spt), rev_sp->gfn); - dump_stack(); - return; - } - - rmap_head = gfn_to_rmap(gfn, rev_sp->role.level, slot); - if (!rmap_head->val) { - if (!__ratelimit(&ratelimit_state)) - return; - audit_printk(kvm, "no rmap for writable spte %llx\n", - *sptep); - dump_stack(); - } -} - -static void audit_sptes_have_rmaps(struct kvm_vcpu *vcpu, u64 *sptep, int level) -{ - if (is_shadow_present_pte(*sptep) && is_last_spte(*sptep, level)) - inspect_spte_has_rmap(vcpu->kvm, sptep); -} - -static void audit_spte_after_sync(struct kvm_vcpu *vcpu, u64 *sptep) -{ - struct kvm_mmu_page *sp = sptep_to_sp(sptep); - - if (vcpu->kvm->arch.audit_point == AUDIT_POST_SYNC && sp->unsync) - audit_printk(vcpu->kvm, "meet unsync sp(%p) after sync " - "root.\n", sp); -} - -static void check_mappings_rmap(struct kvm *kvm, struct kvm_mmu_page *sp) -{ - int i; - - if (sp->role.level != PG_LEVEL_4K) - return; - - for (i = 0; i < PT64_ENT_PER_PAGE; ++i) { - if (!is_shadow_present_pte(sp->spt[i])) - continue; - - inspect_spte_has_rmap(kvm, sp->spt + i); - } -} - -static void audit_write_protection(struct kvm *kvm, struct kvm_mmu_page *sp) -{ - struct kvm_rmap_head *rmap_head; - u64 *sptep; - struct rmap_iterator iter; - struct kvm_memslots *slots; - struct kvm_memory_slot *slot; - - if (sp->role.direct || sp->unsync || sp->role.invalid) - return; - - slots = kvm_memslots_for_spte_role(kvm, sp->role); - slot = __gfn_to_memslot(slots, sp->gfn); - rmap_head = gfn_to_rmap(sp->gfn, PG_LEVEL_4K, slot); - - for_each_rmap_spte(rmap_head, &iter, sptep) { - if (is_writable_pte(*sptep)) - audit_printk(kvm, "shadow page has writable " - "mappings: gfn %llx role %x\n", - sp->gfn, sp->role.word); - } -} - -static void audit_sp(struct kvm *kvm, struct kvm_mmu_page *sp) -{ - check_mappings_rmap(kvm, sp); - audit_write_protection(kvm, sp); -} - -static void audit_all_active_sps(struct kvm *kvm) -{ - walk_all_active_sps(kvm, audit_sp); -} - -static void audit_spte(struct kvm_vcpu *vcpu, u64 *sptep, int level) -{ - audit_sptes_have_rmaps(vcpu, sptep, level); - audit_mappings(vcpu, sptep, level); - audit_spte_after_sync(vcpu, sptep); -} - -static void audit_vcpu_spte(struct kvm_vcpu *vcpu) -{ - mmu_spte_walk(vcpu, audit_spte); -} - -static bool mmu_audit; -static DEFINE_STATIC_KEY_FALSE(mmu_audit_key); - -static void __kvm_mmu_audit(struct kvm_vcpu *vcpu, int point) -{ - static DEFINE_RATELIMIT_STATE(ratelimit_state, 5 * HZ, 10); - - if (!__ratelimit(&ratelimit_state)) - return; - - vcpu->kvm->arch.audit_point = point; - audit_all_active_sps(vcpu->kvm); - audit_vcpu_spte(vcpu); -} - -static inline void kvm_mmu_audit(struct kvm_vcpu *vcpu, int point) -{ - if (static_branch_unlikely((&mmu_audit_key))) - __kvm_mmu_audit(vcpu, point); -} - -static void mmu_audit_enable(void) -{ - if (mmu_audit) - return; - - static_branch_inc(&mmu_audit_key); - mmu_audit = true; -} - -static void mmu_audit_disable(void) -{ - if (!mmu_audit) - return; - - static_branch_dec(&mmu_audit_key); - mmu_audit = false; -} - -static int mmu_audit_set(const char *val, const struct kernel_param *kp) -{ - int ret; - unsigned long enable; - - ret = kstrtoul(val, 10, &enable); - if (ret < 0) - return -EINVAL; - - switch (enable) { - case 0: - mmu_audit_disable(); - break; - case 1: - mmu_audit_enable(); - break; - default: - return -EINVAL; - } - - return 0; -} - -static const struct kernel_param_ops audit_param_ops = { - .set = mmu_audit_set, - .get = param_get_bool, -}; - -arch_param_cb(mmu_audit, &audit_param_ops, &mmu_audit, 0644); diff --git a/arch/x86/kvm/mmu/paging_tmpl.h b/arch/x86/kvm/mmu/paging_tmpl.h index 5b5bdac97c7b..aa0e3c246aca 100644 --- a/arch/x86/kvm/mmu/paging_tmpl.h +++ b/arch/x86/kvm/mmu/paging_tmpl.h @@ -904,12 +904,10 @@ static int FNAME(page_fault)(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault if (is_page_fault_stale(vcpu, fault, mmu_seq)) goto out_unlock; - kvm_mmu_audit(vcpu, AUDIT_PRE_PAGE_FAULT); r = make_mmu_pages_available(vcpu); if (r) goto out_unlock; r = FNAME(fetch)(vcpu, fault, &walker); - kvm_mmu_audit(vcpu, AUDIT_POST_PAGE_FAULT); out_unlock: write_unlock(&vcpu->kvm->mmu_lock); |