diff options
| author | Li RongQing <lirongqing@baidu.com> | 2020-09-27 11:44:57 +0300 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2020-11-08 12:41:26 +0300 |
| commit | c6c4f961cb879aed67b1343bdef2087c899fdaa9 (patch) | |
| tree | 02826adf146aa29c838d5873260848218e906fbc /arch/x86 | |
| parent | ff2bb93f53782bbf7500d521368435921912ad04 (diff) | |
| download | linux-c6c4f961cb879aed67b1343bdef2087c899fdaa9.tar.xz | |
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.c | 12 |
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) |