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path: root/drivers/kvm/kvm_main.c
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Diffstat (limited to 'drivers/kvm/kvm_main.c')
-rw-r--r--drivers/kvm/kvm_main.c6
1 files changed, 4 insertions, 2 deletions
diff --git a/drivers/kvm/kvm_main.c b/drivers/kvm/kvm_main.c
index 7826f16271e5..5603000573ec 100644
--- a/drivers/kvm/kvm_main.c
+++ b/drivers/kvm/kvm_main.c
@@ -1170,8 +1170,10 @@ static int emulator_write_phys(struct kvm_vcpu *vcpu, gpa_t gpa,
return 0;
mark_page_dirty(vcpu->kvm, gpa >> PAGE_SHIFT);
virt = kmap_atomic(page, KM_USER0);
- kvm_mmu_pte_write(vcpu, gpa, virt + offset, val, bytes);
- memcpy(virt + offset_in_page(gpa), val, bytes);
+ if (memcmp(virt + offset_in_page(gpa), val, bytes)) {
+ kvm_mmu_pte_write(vcpu, gpa, virt + offset, val, bytes);
+ memcpy(virt + offset_in_page(gpa), val, bytes);
+ }
kunmap_atomic(virt, KM_USER0);
return 1;
}