linux-kernel - [PATCH 2/4] KVM: x86/mmu: Invert RET_PF_* check when falling through to emulation

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Date:   Wed, 23 Sep 2020 15:04:23 -0700
From:   Sean Christopherson <sean.j.christopherson@...el.com>
To:     Paolo Bonzini <pbonzini@...hat.com>
Cc:     Sean Christopherson <sean.j.christopherson@...el.com>,
        Vitaly Kuznetsov <vkuznets@...hat.com>,
        Wanpeng Li <wanpengli@...cent.com>,
        Jim Mattson <jmattson@...gle.com>,
        Joerg Roedel <joro@...tes.org>, kvm@...r.kernel.org,
        linux-kernel@...r.kernel.org, Kai Huang <kai.huang@...el.com>
Subject: [PATCH 2/4] KVM: x86/mmu: Invert RET_PF_* check when falling through to emulation

Explicitly check for RET_PF_EMULATE instead of implicitly doing the same
by checking for !RET_PF_RETRY (RET_PF_INVALID is handled earlier).  This
will adding new RET_PF_ types in future patches without breaking the
emulation path.

No functional change intended.

Signed-off-by: Sean Christopherson <sean.j.christopherson@...el.com>
---
 arch/x86/kvm/mmu/mmu.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 4a2a8f67a8f7..0b27c4caf5e6 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -5454,10 +5454,10 @@ int kvm_mmu_page_fault(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa, u64 error_code,
 			return -EIO;
 	}
 
-	if (r == RET_PF_RETRY)
-		return 1;
 	if (r < 0)
 		return r;
+	if (r != RET_PF_EMULATE)
+		return 1;
 
 	/*
 	 * Before emulating the instruction, check if the error code
-- 
2.28.0