commit 15e43a98fcde98d03594118051bdc6ce648ed3d5
author Keir Fraser <keirf@google.com> Wed Nov 16 10:53:00 2022 +0000
committer Keir Fraser <keirf@google.com> Thu Sep 05 10:45:07 2024 +0000
tree 51fdf6c43c3f4f8d080fabb914728aca68f7c5d9
parent 05e131d9741e7eab2881640c287838308f24ab01

KVM: arm64: Avoid unnecessary unmap walk in MEM_RELINQUISH hypercall

If the mapping is determined to be not present in an earlier walk,
attempting the unmap is pointless.

Signed-off-by: Keir Fraser <keirf@google.com>

arch/arm64/kvm/hyp/nvhe/mem_protect.c

diff --git a/arch/arm64/kvm/hyp/nvhe/mem_protect.c b/arch/arm64/kvm/hyp/nvhe/mem_protect.c
index e5b6110..b02f226 100644
--- a/arch/arm64/kvm/hyp/nvhe/mem_protect.c
+++ b/arch/arm64/kvm/hyp/nvhe/mem_protect.c
@@ -378,7 +378,7 @@ int __pkvm_guest_relinquish_to_host(struct pkvm_hyp_vcpu *vcpu,
 	ret = kvm_pgtable_walk(&vm->pgt, ipa, PAGE_SIZE, &walker);
 
 	/* Zap the guest stage2 pte. */
-	if (!ret)
+	if (!ret && data.pa)
 		kvm_pgtable_stage2_unmap(&vm->pgt, ipa, PAGE_SIZE);
 
 	guest_unlock_component(vm);