KVM: MMU: Topup the mmu memory preallocation caches before emulating an insn

Emulation may cause a shadow pte to be instantiated, which requires
memory resources.  Make sure the caches are filled to avoid an oops.

Signed-off-by: Avi Kivity <avi@qumranet.com>

diff --git a/drivers/kvm/mmu.c b/drivers/kvm/mmu.c
index ace3cb86214b2979aaad93b580f6b20088c24154..9be54a5e858e9e58986a4dd7423aa9533f1a8e58 100644 (file)
--- a/drivers/kvm/mmu.c
+++ b/drivers/kvm/mmu.c
@@ -1362,6 +1362,10 @@ int kvm_mmu_page_fault(struct kvm_vcpu *vcpu, gva_t cr2, u32 error_code)
                goto out;
        }
 
+       r = mmu_topup_memory_caches(vcpu);
+       if (r)
+               goto out;
+
        er = emulate_instruction(vcpu, vcpu->run, cr2, error_code, 0);
        mutex_unlock(&vcpu->kvm->lock);