diff options
| -rw-r--r-- | arch/x86/kvm/Kconfig | 7 | ||||
| -rw-r--r-- | arch/x86/kvm/mmu.c | 91 | ||||
| -rw-r--r-- | arch/x86/kvm/mmutrace.h | 19 | ||||
| -rw-r--r-- | arch/x86/kvm/paging_tmpl.h | 4 |
4 files changed, 101 insertions, 20 deletions
diff --git a/arch/x86/kvm/Kconfig b/arch/x86/kvm/Kconfig index 970bbd4..ddc131f 100644 --- a/arch/x86/kvm/Kconfig +++ b/arch/x86/kvm/Kconfig @@ -64,6 +64,13 @@ config KVM_AMD To compile this as a module, choose M here: the module will be called kvm-amd. +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 + audit KVM MMU at runtime. + # OK, it's a little counter-intuitive to do this, but it puts it neatly under # the virtualization menu. source drivers/vhost/Kconfig diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index 0bff4d5..8b750ff 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -49,15 +49,21 @@ */ bool tdp_enabled = false; -#undef MMU_DEBUG +enum { + AUDIT_PRE_PAGE_FAULT, + AUDIT_POST_PAGE_FAULT, + AUDIT_PRE_PTE_WRITE, + AUDIT_POST_PTE_WRITE +}; -#undef AUDIT +char *audit_point_name[] = { + "pre page fault", + "post page fault", + "pre pte write", + "post pte write" +}; -#ifdef AUDIT -static void kvm_mmu_audit(struct kvm_vcpu *vcpu, const char *msg); -#else -static void kvm_mmu_audit(struct kvm_vcpu *vcpu, const char *msg) {} -#endif +#undef MMU_DEBUG #ifdef MMU_DEBUG @@ -71,7 +77,7 @@ static void kvm_mmu_audit(struct kvm_vcpu *vcpu, const char *msg) {} #endif -#if defined(MMU_DEBUG) || defined(AUDIT) +#ifdef MMU_DEBUG static int dbg = 0; module_param(dbg, bool, 0644); #endif @@ -2964,7 +2970,7 @@ void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa, kvm_mmu_access_page(vcpu, gfn); kvm_mmu_free_some_pages(vcpu); ++vcpu->kvm->stat.mmu_pte_write; - kvm_mmu_audit(vcpu, "pre pte write"); + trace_kvm_mmu_audit(vcpu, AUDIT_PRE_PTE_WRITE); if (guest_initiated) { if (gfn == vcpu->arch.last_pt_write_gfn && !last_updated_pte_accessed(vcpu)) { @@ -3037,7 +3043,7 @@ void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa, } mmu_pte_write_flush_tlb(vcpu, zap_page, remote_flush, local_flush); kvm_mmu_commit_zap_page(vcpu->kvm, &invalid_list); - kvm_mmu_audit(vcpu, "post pte write"); + trace_kvm_mmu_audit(vcpu, AUDIT_POST_PTE_WRITE); spin_unlock(&vcpu->kvm->mmu_lock); if (!is_error_pfn(vcpu->arch.update_pte.pfn)) { kvm_release_pfn_clean(vcpu->arch.update_pte.pfn); @@ -3483,8 +3489,7 @@ int kvm_mmu_get_spte_hierarchy(struct kvm_vcpu *vcpu, u64 addr, u64 sptes[4]) } EXPORT_SYMBOL_GPL(kvm_mmu_get_spte_hierarchy); -#ifdef AUDIT - +#ifdef CONFIG_KVM_MMU_AUDIT static const char *audit_msg; typedef void (*inspect_spte_fn) (struct kvm *kvm, u64 *sptep); @@ -3699,18 +3704,68 @@ static void audit_write_protection(struct kvm_vcpu *vcpu) } } -static void kvm_mmu_audit(struct kvm_vcpu *vcpu, const char *msg) +static void kvm_mmu_audit(void *ignore, struct kvm_vcpu *vcpu, int audit_point) { - int olddbg = dbg; - - dbg = 0; - audit_msg = msg; + audit_msg = audit_point_name[audit_point]; audit_rmap(vcpu); audit_write_protection(vcpu); if (strcmp("pre pte write", audit_msg) != 0) audit_mappings(vcpu); audit_sptes_have_rmaps(vcpu); - dbg = olddbg; } +static bool mmu_audit; + +static void mmu_audit_enable(void) +{ + int ret; + + if (mmu_audit) + return; + + ret = register_trace_kvm_mmu_audit(kvm_mmu_audit, NULL); + WARN_ON(ret); + + mmu_audit = true; +} + +static void mmu_audit_disable(void) +{ + if (!mmu_audit) + return; + + unregister_trace_kvm_mmu_audit(kvm_mmu_audit, NULL); + tracepoint_synchronize_unregister(); + mmu_audit = false; +} + +static int mmu_audit_set(const char *val, const struct kernel_param *kp) +{ + int ret; + unsigned long enable; + + ret = strict_strtoul(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 struct kernel_param_ops audit_param_ops = { + .set = mmu_audit_set, + .get = param_get_bool, +}; + +module_param_cb(mmu_audit, &audit_param_ops, &mmu_audit, 0644); #endif diff --git a/arch/x86/kvm/mmutrace.h b/arch/x86/kvm/mmutrace.h index 3aab0f0..b60b4fd 100644 --- a/arch/x86/kvm/mmutrace.h +++ b/arch/x86/kvm/mmutrace.h @@ -195,6 +195,25 @@ DEFINE_EVENT(kvm_mmu_page_class, kvm_mmu_prepare_zap_page, TP_ARGS(sp) ); + +TRACE_EVENT( + kvm_mmu_audit, + TP_PROTO(struct kvm_vcpu *vcpu, int audit_point), + TP_ARGS(vcpu, audit_point), + + TP_STRUCT__entry( + __field(struct kvm_vcpu *, vcpu) + __field(int, audit_point) + ), + + TP_fast_assign( + __entry->vcpu = vcpu; + __entry->audit_point = audit_point; + ), + + TP_printk("vcpu:%d %s", __entry->vcpu->cpu, + audit_point_name[__entry->audit_point]) +); #endif /* _TRACE_KVMMMU_H */ #undef TRACE_INCLUDE_PATH diff --git a/arch/x86/kvm/paging_tmpl.h b/arch/x86/kvm/paging_tmpl.h index a0f2feb..debe770 100644 --- a/arch/x86/kvm/paging_tmpl.h +++ b/arch/x86/kvm/paging_tmpl.h @@ -542,7 +542,7 @@ static int FNAME(page_fault)(struct kvm_vcpu *vcpu, gva_t addr, if (mmu_notifier_retry(vcpu, mmu_seq)) goto out_unlock; - kvm_mmu_audit(vcpu, "pre page fault"); + trace_kvm_mmu_audit(vcpu, AUDIT_PRE_PAGE_FAULT); kvm_mmu_free_some_pages(vcpu); sptep = FNAME(fetch)(vcpu, addr, &walker, user_fault, write_fault, level, &write_pt, pfn); @@ -554,7 +554,7 @@ static int FNAME(page_fault)(struct kvm_vcpu *vcpu, gva_t addr, vcpu->arch.last_pt_write_count = 0; /* reset fork detector */ ++vcpu->stat.pf_fixed; - kvm_mmu_audit(vcpu, "post page fault (fixed)"); + trace_kvm_mmu_audit(vcpu, AUDIT_POST_PAGE_FAULT); spin_unlock(&vcpu->kvm->mmu_lock); return write_pt; |