From c53fbdb60fb61fd6bda2bc0dc89837966625c5dc Mon Sep 17 00:00:00 2001 From: Quentin Perret Date: Fri, 7 Feb 2025 14:54:37 +0000 Subject: [PATCH] KVM: arm64: Improve error handling from check_host_shared_guest() The check_host_shared_guest() path expects to find a last-level valid PTE in the guest's stage-2 page-table. However, it checks the PTE's level before its validity, which makes it hard for callers to figure out what went wrong. To make error handling simpler, check the PTE's validity first. Signed-off-by: Quentin Perret Reviewed-by: Oliver Upton Link: https://lore.kernel.org/r/20250207145438.1333475-2-qperret@google.com Signed-off-by: Marc Zyngier --- arch/arm64/kvm/hyp/nvhe/mem_protect.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/arm64/kvm/hyp/nvhe/mem_protect.c b/arch/arm64/kvm/hyp/nvhe/mem_protect.c index 7ad7b133b81a..41847c04b270 100644 --- a/arch/arm64/kvm/hyp/nvhe/mem_protect.c +++ b/arch/arm64/kvm/hyp/nvhe/mem_protect.c @@ -943,10 +943,10 @@ static int __check_host_shared_guest(struct pkvm_hyp_vm *vm, u64 *__phys, u64 ip ret = kvm_pgtable_get_leaf(&vm->pgt, ipa, &pte, &level); if (ret) return ret; - if (level != KVM_PGTABLE_LAST_LEVEL) - return -E2BIG; if (!kvm_pte_valid(pte)) return -ENOENT; + if (level != KVM_PGTABLE_LAST_LEVEL) + return -E2BIG; state = guest_get_page_state(pte, ipa); if (state != PKVM_PAGE_SHARED_BORROWED)