aboutsummaryrefslogtreecommitdiff
path: root/arch/x86
diff options
context:
space:
mode:
authorLi RongQing2020-09-27 16:44:57 +0800
committerPaolo Bonzini2020-11-08 04:41:26 -0500
commitc6c4f961cb879aed67b1343bdef2087c899fdaa9 (patch)
tree02826adf146aa29c838d5873260848218e906fbc /arch/x86
parentff2bb93f53782bbf7500d521368435921912ad04 (diff)
KVM: x86/mmu: fix counting of rmap entries in pte_list_add
Fix an off-by-one style bug in pte_list_add() where it failed to account the last full set of SPTEs, i.e. when desc->sptes is full and desc->more is NULL. Merge the two "PTE_LIST_EXT-1" checks as part of the fix to avoid an extra comparison. Signed-off-by: Li RongQing <lirongqing@baidu.com> Reviewed-by: Sean Christopherson <sean.j.christopherson@intel.com> Message-Id: <1601196297-24104-1-git-send-email-lirongqing@baidu.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch/x86')
-rw-r--r--arch/x86/kvm/mmu/mmu.c12
1 files changed, 7 insertions, 5 deletions
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 1f96adff8dc4..5bb1939b65d8 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -856,12 +856,14 @@ static int pte_list_add(struct kvm_vcpu *vcpu, u64 *spte,
} else {
rmap_printk("pte_list_add: %p %llx many->many\n", spte, *spte);
desc = (struct pte_list_desc *)(rmap_head->val & ~1ul);
- while (desc->sptes[PTE_LIST_EXT-1] && desc->more) {
- desc = desc->more;
+ while (desc->sptes[PTE_LIST_EXT-1]) {
count += PTE_LIST_EXT;
- }
- if (desc->sptes[PTE_LIST_EXT-1]) {
- desc->more = mmu_alloc_pte_list_desc(vcpu);
+
+ if (!desc->more) {
+ desc->more = mmu_alloc_pte_list_desc(vcpu);
+ desc = desc->more;
+ break;
+ }
desc = desc->more;
}
for (i = 0; desc->sptes[i]; ++i)