On 25/08/21 01:34, David Matlack wrote:
The current code is correct but relies on is_error_noslot_pfn() to
ensure slot is not null. The only reason is_error_noslot_pfn() was
checked instead is because we did not have the slot before
commit 6574422f913e ("KVM: x86/mmu: Pass the memslot around via struct
kvm_page_fault") and looking up the memslot is expensive.
Now that the slot is available, explicitly check if it's null and
get rid of the redundant is_error_noslot_pfn() check.
Suggested-by: Sean Christopherson <seanjc@xxxxxxxxxx>
Signed-off-by: David Matlack <dmatlack@xxxxxxxxxx>
---
arch/x86/kvm/mmu/mmu.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 4853c033e6ce..9b5424bcb173 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -2925,10 +2925,10 @@ void kvm_mmu_hugepage_adjust(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault
if (unlikely(fault->max_level == PG_LEVEL_4K))
return;
- if (is_error_noslot_pfn(fault->pfn) || kvm_is_reserved_pfn(fault->pfn))
+ if (!slot || kvm_slot_dirty_track_enabled(slot))
return;
- if (kvm_slot_dirty_track_enabled(slot))
+ if (kvm_is_reserved_pfn(fault->pfn))
return;
/*
Squashed, thanks.
Paolo
