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Diffstat (limited to 'arch/x86/kvm/mmu/mmu.c')
-rw-r--r--arch/x86/kvm/mmu/mmu.c123
1 files changed, 90 insertions, 33 deletions
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 22e7ad235123..d4ac4a1f8b81 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -599,6 +599,12 @@ static int mmu_topup_memory_caches(struct kvm_vcpu *vcpu, bool maybe_indirect)
1 + PT64_ROOT_MAX_LEVEL + PTE_PREFETCH_NUM);
if (r)
return r;
+ if (kvm_has_mirrored_tdp(vcpu->kvm)) {
+ r = kvm_mmu_topup_memory_cache(&vcpu->arch.mmu_external_spt_cache,
+ PT64_ROOT_MAX_LEVEL);
+ if (r)
+ return r;
+ }
r = kvm_mmu_topup_memory_cache(&vcpu->arch.mmu_shadow_page_cache,
PT64_ROOT_MAX_LEVEL);
if (r)
@@ -618,6 +624,7 @@ static void mmu_free_memory_caches(struct kvm_vcpu *vcpu)
kvm_mmu_free_memory_cache(&vcpu->arch.mmu_pte_list_desc_cache);
kvm_mmu_free_memory_cache(&vcpu->arch.mmu_shadow_page_cache);
kvm_mmu_free_memory_cache(&vcpu->arch.mmu_shadowed_info_cache);
+ kvm_mmu_free_memory_cache(&vcpu->arch.mmu_external_spt_cache);
kvm_mmu_free_memory_cache(&vcpu->arch.mmu_page_header_cache);
}
@@ -3364,18 +3371,6 @@ static bool fast_pf_fix_direct_spte(struct kvm_vcpu *vcpu,
return true;
}
-static bool is_access_allowed(struct kvm_page_fault *fault, u64 spte)
-{
- if (fault->exec)
- return is_executable_pte(spte);
-
- if (fault->write)
- return is_writable_pte(spte);
-
- /* Fault was on Read access */
- return spte & PT_PRESENT_MASK;
-}
-
/*
* Returns the last level spte pointer of the shadow page walk for the given
* gpa, and sets *spte to the spte value. This spte may be non-preset. If no
@@ -3668,8 +3663,13 @@ static int mmu_alloc_direct_roots(struct kvm_vcpu *vcpu)
unsigned i;
int r;
- if (tdp_mmu_enabled)
- return kvm_tdp_mmu_alloc_root(vcpu);
+ if (tdp_mmu_enabled) {
+ if (kvm_has_mirrored_tdp(vcpu->kvm) &&
+ !VALID_PAGE(mmu->mirror_root_hpa))
+ kvm_tdp_mmu_alloc_root(vcpu, true);
+ kvm_tdp_mmu_alloc_root(vcpu, false);
+ return 0;
+ }
write_lock(&vcpu->kvm->mmu_lock);
r = make_mmu_pages_available(vcpu);
@@ -4391,8 +4391,12 @@ static int kvm_mmu_faultin_pfn(struct kvm_vcpu *vcpu,
struct kvm_page_fault *fault, unsigned int access)
{
struct kvm_memory_slot *slot = fault->slot;
+ struct kvm *kvm = vcpu->kvm;
int ret;
+ if (KVM_BUG_ON(kvm_is_gfn_alias(kvm, fault->gfn), kvm))
+ return -EFAULT;
+
/*
* Note that the mmu_invalidate_seq also serves to detect a concurrent
* change in attributes. is_page_fault_stale() will detect an
@@ -4406,7 +4410,7 @@ static int kvm_mmu_faultin_pfn(struct kvm_vcpu *vcpu,
* Now that we have a snapshot of mmu_invalidate_seq we can check for a
* private vs. shared mismatch.
*/
- if (fault->is_private != kvm_mem_is_private(vcpu->kvm, fault->gfn)) {
+ if (fault->is_private != kvm_mem_is_private(kvm, fault->gfn)) {
kvm_mmu_prepare_memory_fault_exit(vcpu, fault);
return -EFAULT;
}
@@ -4468,7 +4472,7 @@ static int kvm_mmu_faultin_pfn(struct kvm_vcpu *vcpu,
* *guaranteed* to need to retry, i.e. waiting until mmu_lock is held
* to detect retry guarantees the worst case latency for the vCPU.
*/
- if (mmu_invalidate_retry_gfn_unsafe(vcpu->kvm, fault->mmu_seq, fault->gfn))
+ if (mmu_invalidate_retry_gfn_unsafe(kvm, fault->mmu_seq, fault->gfn))
return RET_PF_RETRY;
ret = __kvm_mmu_faultin_pfn(vcpu, fault);
@@ -4488,7 +4492,7 @@ static int kvm_mmu_faultin_pfn(struct kvm_vcpu *vcpu,
* overall cost of failing to detect the invalidation until after
* mmu_lock is acquired.
*/
- if (mmu_invalidate_retry_gfn_unsafe(vcpu->kvm, fault->mmu_seq, fault->gfn)) {
+ if (mmu_invalidate_retry_gfn_unsafe(kvm, fault->mmu_seq, fault->gfn)) {
kvm_mmu_finish_page_fault(vcpu, fault, RET_PF_RETRY);
return RET_PF_RETRY;
}
@@ -5034,7 +5038,7 @@ static void reset_guest_rsvds_bits_mask(struct kvm_vcpu *vcpu,
__reset_rsvds_bits_mask(&context->guest_rsvd_check,
vcpu->arch.reserved_gpa_bits,
context->cpu_role.base.level, is_efer_nx(context),
- guest_can_use(vcpu, X86_FEATURE_GBPAGES),
+ guest_cpu_cap_has(vcpu, X86_FEATURE_GBPAGES),
is_cr4_pse(context),
guest_cpuid_is_amd_compatible(vcpu));
}
@@ -5111,7 +5115,7 @@ static void reset_shadow_zero_bits_mask(struct kvm_vcpu *vcpu,
__reset_rsvds_bits_mask(shadow_zero_check, reserved_hpa_bits(),
context->root_role.level,
context->root_role.efer_nx,
- guest_can_use(vcpu, X86_FEATURE_GBPAGES),
+ guest_cpu_cap_has(vcpu, X86_FEATURE_GBPAGES),
is_pse, is_amd);
if (!shadow_me_mask)
@@ -5536,7 +5540,7 @@ void kvm_init_shadow_npt_mmu(struct kvm_vcpu *vcpu, unsigned long cr0,
union kvm_mmu_page_role root_role;
/* NPT requires CR0.PG=1. */
- WARN_ON_ONCE(cpu_role.base.direct);
+ WARN_ON_ONCE(cpu_role.base.direct || !cpu_role.base.guest_mode);
root_role = cpu_role.base;
root_role.level = kvm_mmu_get_tdp_level(vcpu);
@@ -6107,8 +6111,16 @@ int noinline kvm_mmu_page_fault(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa, u64 err
else if (r == RET_PF_SPURIOUS)
vcpu->stat.pf_spurious++;
+ /*
+ * None of handle_mmio_page_fault(), kvm_mmu_do_page_fault(), or
+ * kvm_mmu_write_protect_fault() return RET_PF_CONTINUE.
+ * kvm_mmu_do_page_fault() only uses RET_PF_CONTINUE internally to
+ * indicate continuing the page fault handling until to the final
+ * page table mapping phase.
+ */
+ WARN_ON_ONCE(r == RET_PF_CONTINUE);
if (r != RET_PF_EMULATE)
- return 1;
+ return r;
emulate:
return x86_emulate_instruction(vcpu, cr2_or_gpa, emulation_type, insn,
@@ -6284,6 +6296,7 @@ static int __kvm_mmu_create(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu)
mmu->root.hpa = INVALID_PAGE;
mmu->root.pgd = 0;
+ mmu->mirror_root_hpa = INVALID_PAGE;
for (i = 0; i < KVM_MMU_NUM_PREV_ROOTS; i++)
mmu->prev_roots[i] = KVM_MMU_ROOT_INFO_INVALID;
@@ -6453,8 +6466,13 @@ static void kvm_mmu_zap_all_fast(struct kvm *kvm)
* write and in the same critical section as making the reload request,
* e.g. before kvm_zap_obsolete_pages() could drop mmu_lock and yield.
*/
- if (tdp_mmu_enabled)
- kvm_tdp_mmu_invalidate_all_roots(kvm);
+ if (tdp_mmu_enabled) {
+ /*
+ * External page tables don't support fast zapping, therefore
+ * their mirrors must be invalidated separately by the caller.
+ */
+ kvm_tdp_mmu_invalidate_roots(kvm, KVM_DIRECT_ROOTS);
+ }
/*
* Notify all vcpus to reload its shadow page table and flush TLB.
@@ -6479,7 +6497,7 @@ static void kvm_mmu_zap_all_fast(struct kvm *kvm)
* lead to use-after-free.
*/
if (tdp_mmu_enabled)
- kvm_tdp_mmu_zap_invalidated_roots(kvm);
+ kvm_tdp_mmu_zap_invalidated_roots(kvm, true);
}
void kvm_mmu_init_vm(struct kvm *kvm)
@@ -7102,6 +7120,19 @@ static void mmu_destroy_caches(void)
kmem_cache_destroy(mmu_page_header_cache);
}
+static void kvm_wake_nx_recovery_thread(struct kvm *kvm)
+{
+ /*
+ * The NX recovery thread is spawned on-demand at the first KVM_RUN and
+ * may not be valid even though the VM is globally visible. Do nothing,
+ * as such a VM can't have any possible NX huge pages.
+ */
+ struct vhost_task *nx_thread = READ_ONCE(kvm->arch.nx_huge_page_recovery_thread);
+
+ if (nx_thread)
+ vhost_task_wake(nx_thread);
+}
+
static int get_nx_huge_pages(char *buffer, const struct kernel_param *kp)
{
if (nx_hugepage_mitigation_hard_disabled)
@@ -7162,7 +7193,7 @@ static int set_nx_huge_pages(const char *val, const struct kernel_param *kp)
kvm_mmu_zap_all_fast(kvm);
mutex_unlock(&kvm->slots_lock);
- vhost_task_wake(kvm->arch.nx_huge_page_recovery_thread);
+ kvm_wake_nx_recovery_thread(kvm);
}
mutex_unlock(&kvm_lock);
}
@@ -7232,6 +7263,12 @@ out:
void kvm_mmu_destroy(struct kvm_vcpu *vcpu)
{
kvm_mmu_unload(vcpu);
+ if (tdp_mmu_enabled) {
+ read_lock(&vcpu->kvm->mmu_lock);
+ mmu_free_root_page(vcpu->kvm, &vcpu->arch.mmu->mirror_root_hpa,
+ NULL);
+ read_unlock(&vcpu->kvm->mmu_lock);
+ }
free_mmu_pages(&vcpu->arch.root_mmu);
free_mmu_pages(&vcpu->arch.guest_mmu);
mmu_free_memory_caches(vcpu);
@@ -7291,7 +7328,7 @@ static int set_nx_huge_pages_recovery_param(const char *val, const struct kernel
mutex_lock(&kvm_lock);
list_for_each_entry(kvm, &vm_list, vm_list)
- vhost_task_wake(kvm->arch.nx_huge_page_recovery_thread);
+ kvm_wake_nx_recovery_thread(kvm);
mutex_unlock(&kvm_lock);
}
@@ -7423,20 +7460,34 @@ static bool kvm_nx_huge_page_recovery_worker(void *data)
return true;
}
+static void kvm_mmu_start_lpage_recovery(struct once *once)
+{
+ struct kvm_arch *ka = container_of(once, struct kvm_arch, nx_once);
+ struct kvm *kvm = container_of(ka, struct kvm, arch);
+ struct vhost_task *nx_thread;
+
+ kvm->arch.nx_huge_page_last = get_jiffies_64();
+ nx_thread = vhost_task_create(kvm_nx_huge_page_recovery_worker,
+ kvm_nx_huge_page_recovery_worker_kill,
+ kvm, "kvm-nx-lpage-recovery");
+
+ if (!nx_thread)
+ return;
+
+ vhost_task_start(nx_thread);
+
+ /* Make the task visible only once it is fully started. */
+ WRITE_ONCE(kvm->arch.nx_huge_page_recovery_thread, nx_thread);
+}
+
int kvm_mmu_post_init_vm(struct kvm *kvm)
{
if (nx_hugepage_mitigation_hard_disabled)
return 0;
- kvm->arch.nx_huge_page_last = get_jiffies_64();
- kvm->arch.nx_huge_page_recovery_thread = vhost_task_create(
- kvm_nx_huge_page_recovery_worker, kvm_nx_huge_page_recovery_worker_kill,
- kvm, "kvm-nx-lpage-recovery");
-
+ call_once(&kvm->arch.nx_once, kvm_mmu_start_lpage_recovery);
if (!kvm->arch.nx_huge_page_recovery_thread)
return -ENOMEM;
-
- vhost_task_start(kvm->arch.nx_huge_page_recovery_thread);
return 0;
}
@@ -7464,6 +7515,12 @@ bool kvm_arch_pre_set_memory_attributes(struct kvm *kvm,
if (WARN_ON_ONCE(!kvm_arch_has_private_mem(kvm)))
return false;
+ /* Unmap the old attribute page. */
+ if (range->arg.attributes & KVM_MEMORY_ATTRIBUTE_PRIVATE)
+ range->attr_filter = KVM_FILTER_SHARED;
+ else
+ range->attr_filter = KVM_FILTER_PRIVATE;
+
return kvm_unmap_gfn_range(kvm, range);
}