Topup memory caches after walking the GVA->GPA translation during a
shadow page fault, there is no need to ensure the caches are full when
walking the GVA.  As of commit f5a1e9f89504f ("KVM: MMU: remove call
to kvm_mmu_pte_write from walk_addr"), the FNAME(walk_addr) flow no
longer add rmaps via kvm_mmu_pte_write().

This avoids allocating memory in the case that the GVA is unmapped in
the guest, and also provides a paper trail of why/when the memory caches
need to be filled.

Signed-off-by: Sean Christopherson <sean.j.christopher...@intel.com>
---
 arch/x86/kvm/mmu/paging_tmpl.h | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/arch/x86/kvm/mmu/paging_tmpl.h b/arch/x86/kvm/mmu/paging_tmpl.h
index 38c576495048..3de32122f601 100644
--- a/arch/x86/kvm/mmu/paging_tmpl.h
+++ b/arch/x86/kvm/mmu/paging_tmpl.h
@@ -791,10 +791,6 @@ static int FNAME(page_fault)(struct kvm_vcpu *vcpu, gpa_t 
addr, u32 error_code,
 
        pgprintk("%s: addr %lx err %x\n", __func__, addr, error_code);
 
-       r = mmu_topup_memory_caches(vcpu);
-       if (r)
-               return r;
-
        /*
         * If PFEC.RSVD is set, this is a shadow page fault.
         * The bit needs to be cleared before walking guest page tables.
@@ -822,6 +818,10 @@ static int FNAME(page_fault)(struct kvm_vcpu *vcpu, gpa_t 
addr, u32 error_code,
                return RET_PF_EMULATE;
        }
 
+       r = mmu_topup_memory_caches(vcpu);
+       if (r)
+               return r;
+
        vcpu->arch.write_fault_to_shadow_pgtable = false;
 
        is_self_change_mapping = FNAME(is_self_change_mapping)(vcpu,
-- 
2.26.0

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