[PATCH 5.12 300/700] KVM: x86/mmu: Fix return value in tdp_mmu_map_handle_target_level()

[Greg Kroah-Hartman]

From: Kai Huang <kai.huang@xxxxxxxxx>

[ Upstream commit 57a3e96d6d17ae5ac9861ef34af024a627f1c3bb ]

Currently tdp_mmu_map_handle_target_level() returns 0, which is
RET_PF_RETRY, when page fault is actually fixed.  This makes
kvm_tdp_mmu_map() also return RET_PF_RETRY in this case, instead of
RET_PF_FIXED.  Fix by initializing ret to RET_PF_FIXED.

Note that kvm_mmu_page_fault() resumes guest on both RET_PF_RETRY and
RET_PF_FIXED, which means in practice returning the two won't make
difference, so this fix alone won't be necessary for stable tree.

Fixes: bb18842e2111 ("kvm: x86/mmu: Add TDP MMU PF handler")
Reviewed-by: Sean Christopherson <seanjc@xxxxxxxxxx>
Reviewed-by: Ben Gardon <bgardon@xxxxxxxxxx>
Signed-off-by: Kai Huang <kai.huang@xxxxxxxxx>
Message-Id: <f9e8956223a586cd28c090879a8ff40f5eb6d609.1623717884.git.kai.huang@xxxxxxxxx>
Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 arch/x86/kvm/mmu/tdp_mmu.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c
index 018d82e73e31..0aca7dcbcbf9 100644
--- a/arch/x86/kvm/mmu/tdp_mmu.c
+++ b/arch/x86/kvm/mmu/tdp_mmu.c
@@ -745,7 +745,7 @@ static int tdp_mmu_map_handle_target_level(struct kvm_vcpu *vcpu, int write,
 					  kvm_pfn_t pfn, bool prefault)
 {
 	u64 new_spte;
-	int ret = 0;
+	int ret = RET_PF_FIXED;
 	int make_spte_ret = 0;
 
 	if (unlikely(is_noslot_pfn(pfn)))
-- 
2.30.2