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Diffstat (limited to 'arch/x86/kvm/mmu/mmu.c')
-rw-r--r--arch/x86/kvm/mmu/mmu.c605
1 files changed, 246 insertions, 359 deletions
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index a32b847a8089..adc84f0f16ba 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -418,22 +418,24 @@ static inline bool is_access_track_spte(u64 spte)
* requires a full MMU zap). The flag is instead explicitly queried when
* checking for MMIO spte cache hits.
*/
-#define MMIO_SPTE_GEN_MASK GENMASK_ULL(18, 0)
+#define MMIO_SPTE_GEN_MASK GENMASK_ULL(17, 0)
#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)
-#define MMIO_SPTE_GEN_HIGH_START 52
-#define MMIO_SPTE_GEN_HIGH_END 61
+#define MMIO_SPTE_GEN_HIGH_START PT64_SECOND_AVAIL_BITS_SHIFT
+#define MMIO_SPTE_GEN_HIGH_END 62
#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_SPTE_GEN_MASK);
+ BUILD_BUG_ON((MMIO_SPTE_GEN_HIGH_MASK | MMIO_SPTE_GEN_LOW_MASK) & SPTE_SPECIAL_MASK);
mask = (gen << MMIO_SPTE_GEN_LOW_START) & MMIO_SPTE_GEN_LOW_MASK;
mask |= (gen << MMIO_SPTE_GEN_HIGH_START) & MMIO_SPTE_GEN_HIGH_MASK;
@@ -444,8 +446,6 @@ static u64 get_mmio_spte_generation(u64 spte)
{
u64 gen;
- spte &= ~shadow_mmio_mask;
-
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;
@@ -538,16 +538,20 @@ EXPORT_SYMBOL_GPL(kvm_mmu_set_mask_ptes);
static u8 kvm_get_shadow_phys_bits(void)
{
/*
- * boot_cpu_data.x86_phys_bits is reduced when MKTME is detected
- * in CPU detection code, but MKTME treats those reduced bits as
- * 'keyID' thus they are not reserved bits. Therefore for MKTME
- * we should still return physical address bits reported by CPUID.
+ * boot_cpu_data.x86_phys_bits is reduced when MKTME or SME are detected
+ * in CPU detection code, but the processor treats those reduced bits as
+ * 'keyID' thus they are not reserved bits. Therefore KVM needs to look at
+ * the physical address bits reported by CPUID.
*/
- if (!boot_cpu_has(X86_FEATURE_TME) ||
- WARN_ON_ONCE(boot_cpu_data.extended_cpuid_level < 0x80000008))
- return boot_cpu_data.x86_phys_bits;
+ if (likely(boot_cpu_data.extended_cpuid_level >= 0x80000008))
+ return cpuid_eax(0x80000008) & 0xff;
- return cpuid_eax(0x80000008) & 0xff;
+ /*
+ * Quite weird to have VMX or SVM but not MAXPHYADDR; probably a VM with
+ * custom CPUID. Proceed with whatever the kernel found since these features
+ * aren't virtualizable (SME/SEV also require CPUIDs higher than 0x80000008).
+ */
+ return boot_cpu_data.x86_phys_bits;
}
static void kvm_mmu_reset_all_pte_masks(void)
@@ -1260,56 +1264,6 @@ static void unaccount_huge_nx_page(struct kvm *kvm, struct kvm_mmu_page *sp)
list_del(&sp->lpage_disallowed_link);
}
-static bool __mmu_gfn_lpage_is_disallowed(gfn_t gfn, int level,
- struct kvm_memory_slot *slot)
-{
- struct kvm_lpage_info *linfo;
-
- if (slot) {
- linfo = lpage_info_slot(gfn, slot, level);
- return !!linfo->disallow_lpage;
- }
-
- return true;
-}
-
-static bool mmu_gfn_lpage_is_disallowed(struct kvm_vcpu *vcpu, gfn_t gfn,
- int level)
-{
- struct kvm_memory_slot *slot;
-
- slot = kvm_vcpu_gfn_to_memslot(vcpu, gfn);
- return __mmu_gfn_lpage_is_disallowed(gfn, level, slot);
-}
-
-static int host_mapping_level(struct kvm *kvm, gfn_t gfn)
-{
- unsigned long page_size;
- int i, ret = 0;
-
- page_size = kvm_host_page_size(kvm, gfn);
-
- for (i = PT_PAGE_TABLE_LEVEL; i <= PT_MAX_HUGEPAGE_LEVEL; ++i) {
- if (page_size >= KVM_HPAGE_SIZE(i))
- ret = i;
- else
- break;
- }
-
- return ret;
-}
-
-static inline bool memslot_valid_for_gpte(struct kvm_memory_slot *slot,
- bool no_dirty_log)
-{
- if (!slot || slot->flags & KVM_MEMSLOT_INVALID)
- return false;
- if (no_dirty_log && slot->dirty_bitmap)
- return false;
-
- return true;
-}
-
static struct kvm_memory_slot *
gfn_to_memslot_dirty_bitmap(struct kvm_vcpu *vcpu, gfn_t gfn,
bool no_dirty_log)
@@ -1317,40 +1271,14 @@ gfn_to_memslot_dirty_bitmap(struct kvm_vcpu *vcpu, gfn_t gfn,
struct kvm_memory_slot *slot;
slot = kvm_vcpu_gfn_to_memslot(vcpu, gfn);
- if (!memslot_valid_for_gpte(slot, no_dirty_log))
- slot = NULL;
+ if (!slot || slot->flags & KVM_MEMSLOT_INVALID)
+ return NULL;
+ if (no_dirty_log && slot->dirty_bitmap)
+ return NULL;
return slot;
}
-static int mapping_level(struct kvm_vcpu *vcpu, gfn_t large_gfn,
- bool *force_pt_level)
-{
- int host_level, level, max_level;
- struct kvm_memory_slot *slot;
-
- if (unlikely(*force_pt_level))
- return PT_PAGE_TABLE_LEVEL;
-
- slot = kvm_vcpu_gfn_to_memslot(vcpu, large_gfn);
- *force_pt_level = !memslot_valid_for_gpte(slot, true);
- if (unlikely(*force_pt_level))
- return PT_PAGE_TABLE_LEVEL;
-
- host_level = host_mapping_level(vcpu->kvm, large_gfn);
-
- if (host_level == PT_PAGE_TABLE_LEVEL)
- return host_level;
-
- max_level = min(kvm_x86_ops->get_lpage_level(), host_level);
-
- for (level = PT_DIRECTORY_LEVEL; level <= max_level; ++level)
- if (__mmu_gfn_lpage_is_disallowed(large_gfn, level, slot))
- break;
-
- return level - 1;
-}
-
/*
* About rmap_head encoding:
*
@@ -1410,7 +1338,7 @@ pte_list_desc_remove_entry(struct kvm_rmap_head *rmap_head,
if (j != 0)
return;
if (!prev_desc && !desc->more)
- rmap_head->val = (unsigned long)desc->sptes[0];
+ rmap_head->val = 0;
else
if (prev_desc)
prev_desc->more = desc->more;
@@ -1525,7 +1453,7 @@ struct rmap_iterator {
/*
* Iteration must be started by this function. This should also be used after
* removing/dropping sptes from the rmap link because in such cases the
- * information in the itererator may not be valid.
+ * information in the iterator may not be valid.
*
* Returns sptep if found, NULL otherwise.
*/
@@ -2899,6 +2827,26 @@ static bool prepare_zap_oldest_mmu_page(struct kvm *kvm,
return kvm_mmu_prepare_zap_page(kvm, sp, invalid_list);
}
+static int make_mmu_pages_available(struct kvm_vcpu *vcpu)
+{
+ LIST_HEAD(invalid_list);
+
+ if (likely(kvm_mmu_available_pages(vcpu->kvm) >= KVM_MIN_FREE_MMU_PAGES))
+ return 0;
+
+ while (kvm_mmu_available_pages(vcpu->kvm) < KVM_REFILL_PAGES) {
+ if (!prepare_zap_oldest_mmu_page(vcpu->kvm, &invalid_list))
+ break;
+
+ ++vcpu->kvm->stat.mmu_recycled;
+ }
+ kvm_mmu_commit_zap_page(vcpu->kvm, &invalid_list);
+
+ if (!kvm_mmu_available_pages(vcpu->kvm))
+ return -ENOSPC;
+ return 0;
+}
+
/*
* Changing the number of mmu pages allocated to the vm
* Note: if goal_nr_mmu_pages is too small, you will get dead lock
@@ -3099,17 +3047,6 @@ static int set_spte(struct kvm_vcpu *vcpu, u64 *sptep,
spte |= (u64)pfn << PAGE_SHIFT;
if (pte_access & ACC_WRITE_MASK) {
-
- /*
- * Other vcpu creates new sp in the window between
- * mapping_level() and acquiring mmu-lock. We can
- * allow guest to retry the access, the mapping can
- * be fixed if guest refault.
- */
- if (level > PT_PAGE_TABLE_LEVEL &&
- mmu_gfn_lpage_is_disallowed(vcpu, gfn, level))
- goto done;
-
spte |= PT_WRITABLE_MASK | SPTE_MMU_WRITEABLE;
/*
@@ -3141,7 +3078,6 @@ static int set_spte(struct kvm_vcpu *vcpu, u64 *sptep,
set_pte:
if (mmu_spte_update(sptep, spte))
ret |= SET_SPTE_NEED_REMOTE_TLB_FLUSH;
-done:
return ret;
}
@@ -3294,6 +3230,83 @@ static void direct_pte_prefetch(struct kvm_vcpu *vcpu, u64 *sptep)
__direct_pte_prefetch(vcpu, sp, sptep);
}
+static int host_pfn_mapping_level(struct kvm_vcpu *vcpu, gfn_t gfn,
+ kvm_pfn_t pfn, struct kvm_memory_slot *slot)
+{
+ unsigned long hva;
+ pte_t *pte;
+ int level;
+
+ BUILD_BUG_ON(PT_PAGE_TABLE_LEVEL != (int)PG_LEVEL_4K ||
+ PT_DIRECTORY_LEVEL != (int)PG_LEVEL_2M ||
+ PT_PDPE_LEVEL != (int)PG_LEVEL_1G);
+
+ if (!PageCompound(pfn_to_page(pfn)) && !kvm_is_zone_device_pfn(pfn))
+ return PT_PAGE_TABLE_LEVEL;
+
+ /*
+ * Note, using the already-retrieved memslot and __gfn_to_hva_memslot()
+ * is not solely for performance, it's also necessary to avoid the
+ * "writable" check in __gfn_to_hva_many(), which will always fail on
+ * read-only memslots due to gfn_to_hva() assuming writes. Earlier
+ * page fault steps have already verified the guest isn't writing a
+ * read-only memslot.
+ */
+ hva = __gfn_to_hva_memslot(slot, gfn);
+
+ pte = lookup_address_in_mm(vcpu->kvm->mm, hva, &level);
+ if (unlikely(!pte))
+ return PT_PAGE_TABLE_LEVEL;
+
+ return level;
+}
+
+static int kvm_mmu_hugepage_adjust(struct kvm_vcpu *vcpu, gfn_t gfn,
+ int max_level, kvm_pfn_t *pfnp)
+{
+ struct kvm_memory_slot *slot;
+ struct kvm_lpage_info *linfo;
+ kvm_pfn_t pfn = *pfnp;
+ kvm_pfn_t mask;
+ int level;
+
+ if (unlikely(max_level == PT_PAGE_TABLE_LEVEL))
+ return PT_PAGE_TABLE_LEVEL;
+
+ if (is_error_noslot_pfn(pfn) || kvm_is_reserved_pfn(pfn))
+ return PT_PAGE_TABLE_LEVEL;
+
+ slot = gfn_to_memslot_dirty_bitmap(vcpu, gfn, true);
+ if (!slot)
+ return PT_PAGE_TABLE_LEVEL;
+
+ max_level = min(max_level, kvm_x86_ops->get_lpage_level());
+ for ( ; max_level > PT_PAGE_TABLE_LEVEL; max_level--) {
+ linfo = lpage_info_slot(gfn, slot, max_level);
+ if (!linfo->disallow_lpage)
+ break;
+ }
+
+ if (max_level == PT_PAGE_TABLE_LEVEL)
+ return PT_PAGE_TABLE_LEVEL;
+
+ level = host_pfn_mapping_level(vcpu, gfn, pfn, slot);
+ if (level == PT_PAGE_TABLE_LEVEL)
+ return level;
+
+ level = min(level, max_level);
+
+ /*
+ * 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;
+}
+
static void disallowed_hugepage_adjust(struct kvm_shadow_walk_iterator it,
gfn_t gfn, kvm_pfn_t *pfnp, int *levelp)
{
@@ -3318,18 +3331,20 @@ static void disallowed_hugepage_adjust(struct kvm_shadow_walk_iterator it,
}
static int __direct_map(struct kvm_vcpu *vcpu, gpa_t gpa, int write,
- int map_writable, int level, kvm_pfn_t pfn,
- bool prefault, bool lpage_disallowed)
+ int map_writable, int max_level, kvm_pfn_t pfn,
+ bool prefault, bool account_disallowed_nx_lpage)
{
struct kvm_shadow_walk_iterator it;
struct kvm_mmu_page *sp;
- int ret;
+ int level, ret;
gfn_t gfn = gpa >> PAGE_SHIFT;
gfn_t base_gfn = gfn;
- if (!VALID_PAGE(vcpu->arch.mmu->root_hpa))
+ if (WARN_ON(!VALID_PAGE(vcpu->arch.mmu->root_hpa)))
return RET_PF_RETRY;
+ level = kvm_mmu_hugepage_adjust(vcpu, gfn, max_level, &pfn);
+
trace_kvm_mmu_spte_requested(gpa, level, pfn);
for_each_shadow_entry(vcpu, gpa, it) {
/*
@@ -3348,7 +3363,7 @@ static int __direct_map(struct kvm_vcpu *vcpu, gpa_t gpa, int write,
it.level - 1, true, ACC_ALL);
link_shadow_page(vcpu, it.sptep, sp);
- if (lpage_disallowed)
+ if (account_disallowed_nx_lpage)
account_huge_nx_page(vcpu->kvm, sp);
}
}
@@ -3384,45 +3399,6 @@ static int kvm_handle_bad_page(struct kvm_vcpu *vcpu, gfn_t gfn, kvm_pfn_t pfn)
return -EFAULT;
}
-static void transparent_hugepage_adjust(struct kvm_vcpu *vcpu,
- gfn_t gfn, kvm_pfn_t *pfnp,
- int *levelp)
-{
- kvm_pfn_t pfn = *pfnp;
- int level = *levelp;
-
- /*
- * Check if it's a transparent hugepage. If this would be an
- * hugetlbfs page, level wouldn't be set to
- * PT_PAGE_TABLE_LEVEL and there would be no adjustment done
- * here.
- */
- if (!is_error_noslot_pfn(pfn) && !kvm_is_reserved_pfn(pfn) &&
- !kvm_is_zone_device_pfn(pfn) && level == PT_PAGE_TABLE_LEVEL &&
- PageTransCompoundMap(pfn_to_page(pfn)) &&
- !mmu_gfn_lpage_is_disallowed(vcpu, gfn, PT_DIRECTORY_LEVEL)) {
- unsigned long mask;
- /*
- * mmu_notifier_retry was successful and we hold the
- * mmu_lock here, so the pmd can't become splitting
- * from under us, and in turn
- * __split_huge_page_refcount() can't run from under
- * us and we can safely transfer the refcount from
- * PG_tail to PG_head as we switch the pfn to tail to
- * head.
- */
- *levelp = level = PT_DIRECTORY_LEVEL;
- mask = KVM_PAGES_PER_HPAGE(level) - 1;
- VM_BUG_ON((gfn & mask) != (pfn & mask));
- if (pfn & mask) {
- kvm_release_pfn_clean(pfn);
- pfn &= ~mask;
- kvm_get_pfn(pfn);
- *pfnp = pfn;
- }
- }
-}
-
static bool handle_abnormal_pfn(struct kvm_vcpu *vcpu, gva_t gva, gfn_t gfn,
kvm_pfn_t pfn, unsigned access, int *ret_val)
{
@@ -3528,7 +3504,7 @@ static bool is_access_allowed(u32 fault_err_code, u64 spte)
* - true: let the vcpu to access on the same address again.
* - false: let the real page fault path to fix it.
*/
-static bool fast_page_fault(struct kvm_vcpu *vcpu, gva_t gva, int level,
+static bool fast_page_fault(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa,
u32 error_code)
{
struct kvm_shadow_walk_iterator iterator;
@@ -3537,9 +3513,6 @@ static bool fast_page_fault(struct kvm_vcpu *vcpu, gva_t gva, int level,
u64 spte = 0ull;
uint retry_count = 0;
- if (!VALID_PAGE(vcpu->arch.mmu->root_hpa))
- return false;
-
if (!page_fault_can_be_fast(error_code))
return false;
@@ -3548,9 +3521,8 @@ static bool fast_page_fault(struct kvm_vcpu *vcpu, gva_t gva, int level,
do {
u64 new_spte;
- for_each_shadow_entry_lockless(vcpu, gva, iterator, spte)
- if (!is_shadow_present_pte(spte) ||
- iterator.level < level)
+ for_each_shadow_entry_lockless(vcpu, cr2_or_gpa, iterator, spte)
+ if (!is_shadow_present_pte(spte))
break;
sp = page_header(__pa(iterator.sptep));
@@ -3626,71 +3598,13 @@ static bool fast_page_fault(struct kvm_vcpu *vcpu, gva_t gva, int level,
} while (true);
- trace_fast_page_fault(vcpu, gva, error_code, iterator.sptep,
+ trace_fast_page_fault(vcpu, cr2_or_gpa, error_code, iterator.sptep,
spte, fault_handled);
walk_shadow_page_lockless_end(vcpu);
return fault_handled;
}
-static bool try_async_pf(struct kvm_vcpu *vcpu, bool prefault, gfn_t gfn,
- gva_t gva, kvm_pfn_t *pfn, bool write, bool *writable);
-static int make_mmu_pages_available(struct kvm_vcpu *vcpu);
-
-static int nonpaging_map(struct kvm_vcpu *vcpu, gva_t v, u32 error_code,
- gfn_t gfn, bool prefault)
-{
- int r;
- int level;
- bool force_pt_level;
- kvm_pfn_t pfn;
- unsigned long mmu_seq;
- bool map_writable, write = error_code & PFERR_WRITE_MASK;
- bool lpage_disallowed = (error_code & PFERR_FETCH_MASK) &&
- is_nx_huge_page_enabled();
-
- force_pt_level = lpage_disallowed;
- level = mapping_level(vcpu, gfn, &force_pt_level);
- if (likely(!force_pt_level)) {
- /*
- * This path builds a PAE pagetable - so we can map
- * 2mb pages at maximum. Therefore check if the level
- * is larger than that.
- */
- if (level > PT_DIRECTORY_LEVEL)
- level = PT_DIRECTORY_LEVEL;
-
- gfn &= ~(KVM_PAGES_PER_HPAGE(level) - 1);
- }
-
- if (fast_page_fault(vcpu, v, level, error_code))
- return RET_PF_RETRY;
-
- mmu_seq = vcpu->kvm->mmu_notifier_seq;
- smp_rmb();
-
- if (try_async_pf(vcpu, prefault, gfn, v, &pfn, write, &map_writable))
- return RET_PF_RETRY;
-
- if (handle_abnormal_pfn(vcpu, v, gfn, pfn, ACC_ALL, &r))
- return r;
-
- r = RET_PF_RETRY;
- spin_lock(&vcpu->kvm->mmu_lock);
- if (mmu_notifier_retry(vcpu->kvm, mmu_seq))
- goto out_unlock;
- if (make_mmu_pages_available(vcpu) < 0)
- goto out_unlock;
- if (likely(!force_pt_level))
- transparent_hugepage_adjust(vcpu, gfn, &pfn, &level);
- r = __direct_map(vcpu, v, write, map_writable, level, pfn,
- prefault, false);
-out_unlock:
- spin_unlock(&vcpu->kvm->mmu_lock);
- kvm_release_pfn_clean(pfn);
- return r;
-}
-
static void mmu_free_root_page(struct kvm *kvm, hpa_t *root_hpa,
struct list_head *invalid_list)
{
@@ -3981,7 +3895,7 @@ void kvm_mmu_sync_roots(struct kvm_vcpu *vcpu)
}
EXPORT_SYMBOL_GPL(kvm_mmu_sync_roots);
-static gpa_t nonpaging_gva_to_gpa(struct kvm_vcpu *vcpu, gva_t vaddr,
+static gpa_t nonpaging_gva_to_gpa(struct kvm_vcpu *vcpu, gpa_t vaddr,
u32 access, struct x86_exception *exception)
{
if (exception)
@@ -3989,7 +3903,7 @@ static gpa_t nonpaging_gva_to_gpa(struct kvm_vcpu *vcpu, gva_t vaddr,
return vaddr;
}
-static gpa_t nonpaging_gva_to_gpa_nested(struct kvm_vcpu *vcpu, gva_t vaddr,
+static gpa_t nonpaging_gva_to_gpa_nested(struct kvm_vcpu *vcpu, gpa_t vaddr,
u32 access,
struct x86_exception *exception)
{
@@ -4001,20 +3915,14 @@ static gpa_t nonpaging_gva_to_gpa_nested(struct kvm_vcpu *vcpu, gva_t vaddr,
static bool
__is_rsvd_bits_set(struct rsvd_bits_validate *rsvd_check, u64 pte, int level)
{
- int bit7 = (pte >> 7) & 1, low6 = pte & 0x3f;
+ int bit7 = (pte >> 7) & 1;
- return (pte & rsvd_check->rsvd_bits_mask[bit7][level-1]) |
- ((rsvd_check->bad_mt_xwr & (1ull << low6)) != 0);
+ return pte & rsvd_check->rsvd_bits_mask[bit7][level-1];
}
-static bool is_rsvd_bits_set(struct kvm_mmu *mmu, u64 gpte, int level)
+static bool __is_bad_mt_xwr(struct rsvd_bits_validate *rsvd_check, u64 pte)
{
- return __is_rsvd_bits_set(&mmu->guest_rsvd_check, gpte, level);
-}
-
-static bool is_shadow_zero_bits_set(struct kvm_mmu *mmu, u64 spte, int level)
-{
- return __is_rsvd_bits_set(&mmu->shadow_zero_check, spte, level);
+ return rsvd_check->bad_mt_xwr & BIT_ULL(pte & 0x3f);
}
static bool mmio_info_in_cache(struct kvm_vcpu *vcpu, u64 addr, bool direct)
@@ -4038,11 +3946,11 @@ walk_shadow_page_get_mmio_spte(struct kvm_vcpu *vcpu, u64 addr, u64 *sptep)
{
struct kvm_shadow_walk_iterator iterator;
u64 sptes[PT64_ROOT_MAX_LEVEL], spte = 0ull;
+ struct rsvd_bits_validate *rsvd_check;
int root, leaf;
bool reserved = false;
- if (!VALID_PAGE(vcpu->arch.mmu->root_hpa))
- goto exit;
+ rsvd_check = &vcpu->arch.mmu->shadow_zero_check;
walk_shadow_page_lockless_begin(vcpu);
@@ -4058,8 +3966,13 @@ walk_shadow_page_get_mmio_spte(struct kvm_vcpu *vcpu, u64 addr, u64 *sptep)
if (!is_shadow_present_pte(spte))
break;
- reserved |= is_shadow_zero_bits_set(vcpu->arch.mmu, spte,
- iterator.level);
+ /*
+ * Use a bitwise-OR instead of a logical-OR to aggregate the
+ * reserved bit and EPT's invalid memtype/XWR checks to avoid
+ * adding a Jcc in the loop.
+ */
+ reserved |= __is_bad_mt_xwr(rsvd_check, spte) |
+ __is_rsvd_bits_set(rsvd_check, spte, iterator.level);
}
walk_shadow_page_lockless_end(vcpu);
@@ -4073,7 +3986,7 @@ walk_shadow_page_get_mmio_spte(struct kvm_vcpu *vcpu, u64 addr, u64 *sptep)
root--;
}
}
-exit:
+
*sptep = spte;
return reserved;
}
@@ -4137,9 +4050,6 @@ static void shadow_page_table_clear_flood(struct kvm_vcpu *vcpu, gva_t addr)
struct kvm_shadow_walk_iterator iterator;
u64 spte;
- if (!VALID_PAGE(vcpu->arch.mmu->root_hpa))
- return;
-
walk_shadow_page_lockless_begin(vcpu);
for_each_shadow_entry_lockless(vcpu, addr, iterator, spte) {
clear_sp_write_flooding_count(iterator.sptep);
@@ -4149,29 +4059,8 @@ static void shadow_page_table_clear_flood(struct kvm_vcpu *vcpu, gva_t addr)
walk_shadow_page_lockless_end(vcpu);
}
-static int nonpaging_page_fault(struct kvm_vcpu *vcpu, gva_t gva,
- u32 error_code, bool prefault)
-{
- gfn_t gfn = gva >> PAGE_SHIFT;
- int r;
-
- pgprintk("%s: gva %lx error %x\n", __func__, gva, error_code);
-
- if (page_fault_handle_page_track(vcpu, error_code, gfn))
- return RET_PF_EMULATE;
-
- r = mmu_topup_memory_caches(vcpu);
- if (r)
- return r;
-
- MMU_WARN_ON(!VALID_PAGE(vcpu->arch.mmu->root_hpa));
-
-
- return nonpaging_map(vcpu, gva & PAGE_MASK,
- error_code, gfn, prefault);
-}
-
-static int kvm_arch_setup_async_pf(struct kvm_vcpu *vcpu, gva_t gva, gfn_t gfn)
+static int kvm_arch_setup_async_pf(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa,
+ gfn_t gfn)
{
struct kvm_arch_async_pf arch;
@@ -4180,11 +4069,13 @@ static int kvm_arch_setup_async_pf(struct kvm_vcpu *vcpu, gva_t gva, gfn_t gfn)
arch.direct_map = vcpu->arch.mmu->direct_map;
arch.cr3 = vcpu->arch.mmu->get_cr3(vcpu);
- return kvm_setup_async_pf(vcpu, gva, kvm_vcpu_gfn_to_hva(vcpu, gfn), &arch);
+ return kvm_setup_async_pf(vcpu, cr2_or_gpa,
+ kvm_vcpu_gfn_to_hva(vcpu, gfn), &arch);
}
static bool try_async_pf(struct kvm_vcpu *vcpu, bool prefault, gfn_t gfn,
- gva_t gva, kvm_pfn_t *pfn, bool write, bool *writable)
+ gpa_t cr2_or_gpa, kvm_pfn_t *pfn, bool write,
+ bool *writable)
{
struct kvm_memory_slot *slot;
bool async;
@@ -4204,12 +4095,12 @@ static bool try_async_pf(struct kvm_vcpu *vcpu, bool prefault, gfn_t gfn,
return false; /* *pfn has correct page already */
if (!prefault && kvm_can_do_async_pf(vcpu)) {
- trace_kvm_try_async_get_page(gva, gfn);
+ trace_kvm_try_async_get_page(cr2_or_gpa, gfn);
if (kvm_find_async_pf_gfn(vcpu, gfn)) {
- trace_kvm_async_pf_doublefault(gva, gfn);
+ trace_kvm_async_pf_doublefault(cr2_or_gpa, gfn);
kvm_make_request(KVM_REQ_APF_HALT, vcpu);
return true;
- } else if (kvm_arch_setup_async_pf(vcpu, gva, gfn))
+ } else if (kvm_arch_setup_async_pf(vcpu, cr2_or_gpa, gfn))
return true;
}
@@ -4217,11 +4108,77 @@ static bool try_async_pf(struct kvm_vcpu *vcpu, bool prefault, gfn_t gfn,
return false;
}
+static int direct_page_fault(struct kvm_vcpu *vcpu, gpa_t gpa, u32 error_code,
+ bool prefault, int max_level, bool is_tdp)
+{
+ bool write = error_code & PFERR_WRITE_MASK;
+ bool exec = error_code & PFERR_FETCH_MASK;
+ bool lpage_disallowed = exec && is_nx_huge_page_enabled();
+ bool map_writable;
+
+ gfn_t gfn = gpa >> PAGE_SHIFT;
+ unsigned long mmu_seq;
+ kvm_pfn_t pfn;
+ int r;
+
+ if (page_fault_handle_page_track(vcpu, error_code, gfn))
+ return RET_PF_EMULATE;
+
+ r = mmu_topup_memory_caches(vcpu);
+ if (r)
+ return r;
+
+ if (lpage_disallowed)
+ max_level = PT_PAGE_TABLE_LEVEL;
+
+ if (fast_page_fault(vcpu, gpa, error_code))
+ return RET_PF_RETRY;
+
+ mmu_seq = vcpu->kvm->mmu_notifier_seq;
+ smp_rmb();
+
+ if (try_async_pf(vcpu, prefault, gfn, gpa, &pfn, write, &map_writable))
+ return RET_PF_RETRY;
+
+ if (handle_abnormal_pfn(vcpu, is_tdp ? 0 : gpa, gfn, pfn, ACC_ALL, &r))
+ return r;
+
+ r = RET_PF_RETRY;
+ spin_lock(&vcpu->kvm->mmu_lock);
+ if (mmu_notifier_retry(vcpu->kvm, mmu_seq))
+ goto out_unlock;
+ if (make_mmu_pages_available(vcpu) < 0)
+ goto out_unlock;
+ r = __direct_map(vcpu, gpa, write, map_writable, max_level, pfn,
+ prefault, is_tdp && lpage_disallowed);
+
+out_unlock:
+ spin_unlock(&vcpu->kvm->mmu_lock);
+ kvm_release_pfn_clean(pfn);
+ return r;
+}
+
+static int nonpaging_page_fault(struct kvm_vcpu *vcpu, gpa_t gpa,
+ u32 error_code, bool prefault)
+{
+ pgprintk("%s: gva %lx error %x\n", __func__, gpa, 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,
+ PT_DIRECTORY_LEVEL, false);
+}
+
int kvm_handle_page_fault(struct kvm_vcpu *vcpu, u64 error_code,
u64 fault_address, char *insn, int insn_len)
{
int r = 1;
+#ifndef CONFIG_X86_64
+ /* A 64-bit CR2 should be impossible on 32-bit KVM. */
+ if (WARN_ON_ONCE(fault_address >> 32))
+ return -EFAULT;
+#endif
+
vcpu->arch.l1tf_flush_l1d = true;
switch (vcpu->arch.apf.host_apf_reason) {
default:
@@ -4249,76 +4206,23 @@ int kvm_handle_page_fault(struct kvm_vcpu *vcpu, u64 error_code,
}
EXPORT_SYMBOL_GPL(kvm_handle_page_fault);
-static bool
-check_hugepage_cache_consistency(struct kvm_vcpu *vcpu, gfn_t gfn, int level)
-{
- int page_num = KVM_PAGES_PER_HPAGE(level);
-
- gfn &= ~(page_num - 1);
-
- return kvm_mtrr_check_gfn_range_consistency(vcpu, gfn, page_num);
-}
-
-static int tdp_page_fault(struct kvm_vcpu *vcpu, gva_t gpa, u32 error_code,
+static int tdp_page_fault(struct kvm_vcpu *vcpu, gpa_t gpa, u32 error_code,
bool prefault)
{
- kvm_pfn_t pfn;
- int r;
- int level;
- bool force_pt_level;
- gfn_t gfn = gpa >> PAGE_SHIFT;
- unsigned long mmu_seq;
- int write = error_code & PFERR_WRITE_MASK;
- bool map_writable;
- bool lpage_disallowed = (error_code & PFERR_FETCH_MASK) &&
- is_nx_huge_page_enabled();
-
- MMU_WARN_ON(!VALID_PAGE(vcpu->arch.mmu->root_hpa));
+ int max_level;
- if (page_fault_handle_page_track(vcpu, error_code, gfn))
- return RET_PF_EMULATE;
+ for (max_level = PT_MAX_HUGEPAGE_LEVEL;
+ max_level > PT_PAGE_TABLE_LEVEL;
+ max_level--) {
+ int page_num = KVM_PAGES_PER_HPAGE(max_level);
+ gfn_t base = (gpa >> PAGE_SHIFT) & ~(page_num - 1);
- r = mmu_topup_memory_caches(vcpu);
- if (r)
- return r;
-
- force_pt_level =
- lpage_disallowed ||
- !check_hugepage_cache_consistency(vcpu, gfn, PT_DIRECTORY_LEVEL);
- level = mapping_level(vcpu, gfn, &force_pt_level);
- if (likely(!force_pt_level)) {
- if (level > PT_DIRECTORY_LEVEL &&
- !check_hugepage_cache_consistency(vcpu, gfn, level))
- level = PT_DIRECTORY_LEVEL;
- gfn &= ~(KVM_PAGES_PER_HPAGE(level) - 1);
+ if (kvm_mtrr_check_gfn_range_consistency(vcpu, base, page_num))
+ break;
}
- if (fast_page_fault(vcpu, gpa, level, error_code))
- return RET_PF_RETRY;
-
- mmu_seq = vcpu->kvm->mmu_notifier_seq;
- smp_rmb();
-
- if (try_async_pf(vcpu, prefault, gfn, gpa, &pfn, write, &map_writable))
- return RET_PF_RETRY;
-
- if (handle_abnormal_pfn(vcpu, 0, gfn, pfn, ACC_ALL, &r))
- return r;
-
- r = RET_PF_RETRY;
- spin_lock(&vcpu->kvm->mmu_lock);
- if (mmu_notifier_retry(vcpu->kvm, mmu_seq))
- goto out_unlock;
- if (make_mmu_pages_available(vcpu) < 0)
- goto out_unlock;
- if (likely(!force_pt_level))
- transparent_hugepage_adjust(vcpu, gfn, &pfn, &level);
- r = __direct_map(vcpu, gpa, write, map_writable, level, pfn,
- prefault, lpage_disallowed);
-out_unlock:
- spin_unlock(&vcpu->kvm->mmu_lock);
- kvm_release_pfn_clean(pfn);
- return r;
+ return direct_page_fault(vcpu, gpa, error_code, prefault,
+ max_level, true);
}
static void nonpaging_init_context(struct kvm_vcpu *vcpu,
@@ -5496,47 +5400,30 @@ int kvm_mmu_unprotect_page_virt(struct kvm_vcpu *vcpu, gva_t gva)
}
EXPORT_SYMBOL_GPL(kvm_mmu_unprotect_page_virt);
-static int make_mmu_pages_available(struct kvm_vcpu *vcpu)
-{
- LIST_HEAD(invalid_list);
-
- if (likely(kvm_mmu_available_pages(vcpu->kvm) >= KVM_MIN_FREE_MMU_PAGES))
- return 0;
-
- while (kvm_mmu_available_pages(vcpu->kvm) < KVM_REFILL_PAGES) {
- if (!prepare_zap_oldest_mmu_page(vcpu->kvm, &invalid_list))
- break;
-
- ++vcpu->kvm->stat.mmu_recycled;
- }
- kvm_mmu_commit_zap_page(vcpu->kvm, &invalid_list);
-
- if (!kvm_mmu_available_pages(vcpu->kvm))
- return -ENOSPC;
- return 0;
-}
-
-int kvm_mmu_page_fault(struct kvm_vcpu *vcpu, gva_t cr2, u64 error_code,
+int kvm_mmu_page_fault(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa, u64 error_code,
void *insn, int insn_len)
{
int r, emulation_type = 0;
bool direct = vcpu->arch.mmu->direct_map;
+ if (WARN_ON(!VALID_PAGE(vcpu->arch.mmu->root_hpa)))
+ return RET_PF_RETRY;
+
/* With shadow page tables, fault_address contains a GVA or nGPA. */
if (vcpu->arch.mmu->direct_map) {
vcpu->arch.gpa_available = true;
- vcpu->arch.gpa_val = cr2;
+ vcpu->arch.gpa_val = cr2_or_gpa;
}
r = RET_PF_INVALID;
if (unlikely(error_code & PFERR_RSVD_MASK)) {
- r = handle_mmio_page_fault(vcpu, cr2, direct);
+ r = handle_mmio_page_fault(vcpu, cr2_or_gpa, direct);
if (r == RET_PF_EMULATE)
goto emulate;
}
if (r == RET_PF_INVALID) {
- r = vcpu->arch.mmu->page_fault(vcpu, cr2,
+ r = vcpu->arch.mmu->page_fault(vcpu, cr2_or_gpa,
lower_32_bits(error_code),
false);
WARN_ON(r == RET_PF_INVALID);
@@ -5556,7 +5443,7 @@ int kvm_mmu_page_fault(struct kvm_vcpu *vcpu, gva_t cr2, u64 error_code,
*/
if (vcpu->arch.mmu->direct_map &&
(error_code & PFERR_NESTED_GUEST_PAGE) == PFERR_NESTED_GUEST_PAGE) {
- kvm_mmu_unprotect_page(vcpu->kvm, gpa_to_gfn(cr2));
+ kvm_mmu_unprotect_page(vcpu->kvm, gpa_to_gfn(cr2_or_gpa));
return 1;
}
@@ -5571,7 +5458,7 @@ int kvm_mmu_page_fault(struct kvm_vcpu *vcpu, gva_t cr2, u64 error_code,
* explicitly shadowing L1's page tables, i.e. unprotecting something
* for L1 isn't going to magically fix whatever issue cause L2 to fail.
*/
- if (!mmio_info_in_cache(vcpu, cr2, direct) && !is_guest_mode(vcpu))
+ if (!mmio_info_in_cache(vcpu, cr2_or_gpa, direct) && !is_guest_mode(vcpu))
emulation_type = EMULTYPE_ALLOW_RETRY;
emulate:
/*
@@ -5586,7 +5473,7 @@ emulate:
return 1;
}
- return x86_emulate_instruction(vcpu, cr2, emulation_type, insn,
+ return x86_emulate_instruction(vcpu, cr2_or_gpa, emulation_type, insn,
insn_len);
}
EXPORT_SYMBOL_GPL(kvm_mmu_page_fault);
@@ -6015,8 +5902,8 @@ restart:
* mapping if the indirect sp has level = 1.
*/
if (sp->role.direct && !kvm_is_reserved_pfn(pfn) &&
- !kvm_is_zone_device_pfn(pfn) &&
- PageTransCompoundMap(pfn_to_page(pfn))) {
+ (kvm_is_zone_device_pfn(pfn) ||
+ PageCompound(pfn_to_page(pfn)))) {
pte_list_remove(rmap_head, sptep);
if (kvm_available_flush_tlb_with_range())
@@ -6249,7 +6136,7 @@ static void kvm_set_mmio_spte_mask(void)
* If reserved bit is not supported, clear the present bit to disable
* mmio page fault.
*/
- if (IS_ENABLED(CONFIG_X86_64) && shadow_phys_bits == 52)
+ if (shadow_phys_bits == 52)
mask &= ~1ull;
kvm_mmu_set_mmio_spte_mask(mask, mask, ACC_WRITE_MASK | ACC_USER_MASK);