* set bit 0 if execute only is supported. Here, we repurpose ACC_USER_MASK
* to signify readability since it isn't used in the EPT case
*/
-static inline unsigned FNAME(gpte_access)(struct kvm_vcpu *vcpu, u64 gpte)
+static inline unsigned FNAME(gpte_access)(u64 gpte)
{
unsigned access;
#if PTTYPE == PTTYPE_EPT
}
/*
- * Fetch a guest pte for a guest virtual address
+ * Fetch a guest pte for a guest virtual address, or for an L2's GPA.
*/
static int FNAME(walk_addr_generic)(struct guest_walker *walker,
struct kvm_vcpu *vcpu, struct kvm_mmu *mmu,
- gva_t addr, u32 access)
+ gpa_t addr, u32 access)
{
int ret;
pt_element_t pte;
accessed_dirty = have_ad ? pte_access & PT_GUEST_ACCESSED_MASK : 0;
/* Convert to ACC_*_MASK flags for struct guest_walker. */
- walker->pt_access = FNAME(gpte_access)(vcpu, pt_access ^ walk_nx_mask);
- walker->pte_access = FNAME(gpte_access)(vcpu, pte_access ^ walk_nx_mask);
+ walker->pt_access = FNAME(gpte_access)(pt_access ^ walk_nx_mask);
+ walker->pte_access = FNAME(gpte_access)(pte_access ^ walk_nx_mask);
errcode = permission_fault(vcpu, mmu, walker->pte_access, pte_pkey, access);
if (unlikely(errcode))
goto error;
* done by is_rsvd_bits_set() above.
*
* We set up the value of exit_qualification to inject:
- * [2:0] - Derive from [2:0] of real exit_qualification at EPT violation
+ * [2:0] - Derive from the access bits. The exit_qualification might be
+ * out of date if it is serving an EPT misconfiguration.
* [5:3] - Calculated by the page walk of the guest EPT page tables
* [7:8] - Derived from [7:8] of real exit_qualification
*
* The other bits are set to 0.
*/
if (!(errcode & PFERR_RSVD_MASK)) {
- vcpu->arch.exit_qualification &= 0x187;
+ vcpu->arch.exit_qualification &= 0x180;
+ if (write_fault)
+ vcpu->arch.exit_qualification |= EPT_VIOLATION_ACC_WRITE;
+ if (user_fault)
+ vcpu->arch.exit_qualification |= EPT_VIOLATION_ACC_READ;
+ if (fetch_fault)
+ vcpu->arch.exit_qualification |= EPT_VIOLATION_ACC_INSTR;
vcpu->arch.exit_qualification |= (pte_access & 0x7) << 3;
}
#endif
}
static int FNAME(walk_addr)(struct guest_walker *walker,
- struct kvm_vcpu *vcpu, gva_t addr, u32 access)
+ struct kvm_vcpu *vcpu, gpa_t addr, u32 access)
{
return FNAME(walk_addr_generic)(walker, vcpu, &vcpu->arch.mmu, addr,
access);
pgprintk("%s: gpte %llx spte %p\n", __func__, (u64)gpte, spte);
gfn = gpte_to_gfn(gpte);
- pte_access = sp->role.access & FNAME(gpte_access)(vcpu, gpte);
+ pte_access = sp->role.access & FNAME(gpte_access)(gpte);
FNAME(protect_clean_gpte)(&vcpu->arch.mmu, &pte_access, gpte);
pfn = pte_prefetch_gfn_to_pfn(vcpu, gfn,
no_dirty_log && (pte_access & ACC_WRITE_MASK));
mmu_set_spte(vcpu, spte, pte_access, 0, PT_PAGE_TABLE_LEVEL, gfn, pfn,
true, true);
+ kvm_release_pfn_clean(pfn);
return true;
}
* If the guest tries to write a write-protected page, we need to
* emulate this operation, return 1 to indicate this case.
*/
-static int FNAME(fetch)(struct kvm_vcpu *vcpu, gva_t addr,
+static int FNAME(fetch)(struct kvm_vcpu *vcpu, gpa_t addr,
struct guest_walker *gw,
int write_fault, int hlevel,
- kvm_pfn_t pfn, bool map_writable, bool prefault)
+ kvm_pfn_t pfn, bool map_writable, bool prefault,
+ bool lpage_disallowed)
{
struct kvm_mmu_page *sp = NULL;
struct kvm_shadow_walk_iterator it;
unsigned direct_access, access = gw->pt_access;
int top_level, ret;
+ gfn_t gfn, base_gfn;
direct_access = gw->pte_access;
link_shadow_page(vcpu, it.sptep, sp);
}
- for (;
- shadow_walk_okay(&it) && it.level > hlevel;
- shadow_walk_next(&it)) {
- gfn_t direct_gfn;
+ /*
+ * FNAME(page_fault) might have clobbered the bottom bits of
+ * gw->gfn, restore them from the virtual address.
+ */
+ gfn = gw->gfn | ((addr & PT_LVL_OFFSET_MASK(gw->level)) >> PAGE_SHIFT);
+ base_gfn = gfn;
+ trace_kvm_mmu_spte_requested(addr, gw->level, pfn);
+
+ for (; shadow_walk_okay(&it); shadow_walk_next(&it)) {
clear_sp_write_flooding_count(it.sptep);
- validate_direct_spte(vcpu, it.sptep, direct_access);
- drop_large_spte(vcpu, it.sptep);
+ /*
+ * We cannot overwrite existing page tables with an NX
+ * large page, as the leaf could be executable.
+ */
+ disallowed_hugepage_adjust(it, gfn, &pfn, &hlevel);
- if (is_shadow_present_pte(*it.sptep))
- continue;
+ base_gfn = gfn & ~(KVM_PAGES_PER_HPAGE(it.level) - 1);
+ if (it.level == hlevel)
+ break;
- direct_gfn = gw->gfn & ~(KVM_PAGES_PER_HPAGE(it.level) - 1);
+ validate_direct_spte(vcpu, it.sptep, direct_access);
- sp = kvm_mmu_get_page(vcpu, direct_gfn, addr, it.level-1,
- true, direct_access);
- link_shadow_page(vcpu, it.sptep, sp);
+ drop_large_spte(vcpu, it.sptep);
+
+ if (!is_shadow_present_pte(*it.sptep)) {
+ sp = kvm_mmu_get_page(vcpu, base_gfn, addr,
+ it.level - 1, true, direct_access);
+ link_shadow_page(vcpu, it.sptep, sp);
+ if (lpage_disallowed)
+ account_huge_nx_page(vcpu->kvm, sp);
+ }
}
- clear_sp_write_flooding_count(it.sptep);
ret = mmu_set_spte(vcpu, it.sptep, gw->pte_access, write_fault,
- it.level, gw->gfn, pfn, prefault, map_writable);
+ it.level, base_gfn, pfn, prefault, map_writable);
FNAME(pte_prefetch)(vcpu, gw, it.sptep);
-
+ ++vcpu->stat.pf_fixed;
return ret;
out_gpte_changed:
- kvm_release_pfn_clean(pfn);
return RET_PF_RETRY;
}
* Returns: 1 if we need to emulate the instruction, 0 otherwise, or
* a negative value on error.
*/
-static int FNAME(page_fault)(struct kvm_vcpu *vcpu, gva_t addr, u32 error_code,
+static int FNAME(page_fault)(struct kvm_vcpu *vcpu, gpa_t addr, u32 error_code,
bool prefault)
{
int write_fault = error_code & PFERR_WRITE_MASK;
int r;
kvm_pfn_t pfn;
int level = PT_PAGE_TABLE_LEVEL;
- bool force_pt_level = false;
unsigned long mmu_seq;
bool map_writable, is_self_change_mapping;
+ bool lpage_disallowed = (error_code & PFERR_FETCH_MASK) &&
+ is_nx_huge_page_enabled();
+ bool force_pt_level = lpage_disallowed;
pgprintk("%s: addr %lx err %x\n", __func__, addr, error_code);
walker.pte_access &= ~ACC_EXEC_MASK;
}
+ 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 (!force_pt_level)
- transparent_hugepage_adjust(vcpu, &walker.gfn, &pfn, &level);
+ transparent_hugepage_adjust(vcpu, walker.gfn, &pfn, &level);
r = FNAME(fetch)(vcpu, addr, &walker, write_fault,
- level, pfn, map_writable, prefault);
- ++vcpu->stat.pf_fixed;
+ level, pfn, map_writable, prefault, lpage_disallowed);
kvm_mmu_audit(vcpu, AUDIT_POST_PAGE_FAULT);
- spin_unlock(&vcpu->kvm->mmu_lock);
-
- return r;
out_unlock:
spin_unlock(&vcpu->kvm->mmu_lock);
kvm_release_pfn_clean(pfn);
- return RET_PF_RETRY;
+ return r;
}
static gpa_t FNAME(get_level1_sp_gpa)(struct kvm_mmu_page *sp)
spin_unlock(&vcpu->kvm->mmu_lock);
}
-static gpa_t FNAME(gva_to_gpa)(struct kvm_vcpu *vcpu, gva_t vaddr, u32 access,
+/* Note, @addr is a GPA when gva_to_gpa() translates an L2 GPA to an L1 GPA. */
+static gpa_t FNAME(gva_to_gpa)(struct kvm_vcpu *vcpu, gpa_t addr, u32 access,
struct x86_exception *exception)
{
struct guest_walker walker;
gpa_t gpa = UNMAPPED_GVA;
int r;
- r = FNAME(walk_addr)(&walker, vcpu, vaddr, access);
+ r = FNAME(walk_addr)(&walker, vcpu, addr, access);
if (r) {
gpa = gfn_to_gpa(walker.gfn);
- gpa |= vaddr & ~PAGE_MASK;
+ gpa |= addr & ~PAGE_MASK;
} else if (exception)
*exception = walker.fault;
}
#if PTTYPE != PTTYPE_EPT
-static gpa_t FNAME(gva_to_gpa_nested)(struct kvm_vcpu *vcpu, gva_t vaddr,
+/* Note, gva_to_gpa_nested() is only used to translate L2 GVAs. */
+static gpa_t FNAME(gva_to_gpa_nested)(struct kvm_vcpu *vcpu, gpa_t vaddr,
u32 access,
struct x86_exception *exception)
{
gpa_t gpa = UNMAPPED_GVA;
int r;
+#ifndef CONFIG_X86_64
+ /* A 64-bit GVA should be impossible on 32-bit KVM. */
+ WARN_ON_ONCE(vaddr >> 32);
+#endif
+
r = FNAME(walk_addr_nested)(&walker, vcpu, vaddr, access);
if (r) {
gfn = gpte_to_gfn(gpte);
pte_access = sp->role.access;
- pte_access &= FNAME(gpte_access)(vcpu, gpte);
+ pte_access &= FNAME(gpte_access)(gpte);
FNAME(protect_clean_gpte)(&vcpu->arch.mmu, &pte_access, gpte);
if (sync_mmio_spte(vcpu, &sp->spt[i], gfn, pte_access,
projects / mirror_ubuntu-bionic-kernel.git / blobdiff