From:   Lai Jiangshan <jiangshanlai@gmail.com>
To:     linux-kernel@vger.kernel.org
Cc:     Paolo Bonzini <pbonzini@redhat.com>,
        Sean Christopherson <seanjc@google.com>,
        Lai Jiangshan <jiangshan.ljs@antgroup.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        Dave Hansen <dave.hansen@linux.intel.com>, x86@kernel.org,
        "H. Peter Anvin" <hpa@zytor.com>, kvm@vger.kernel.org
Subject: [PATCH V3 11/14] kvm: x86/mmu: Allow the roots to be invalid in FNAME(invlpg)
Date:   Fri, 17 Feb 2023 07:53:18 +0800
Message-Id: <20230216235321.735214-2-jiangshanlai@gmail.com>
In-Reply-To: <20230216235321.735214-1-jiangshanlai@gmail.com>
References: <20230216154115.710033-1-jiangshanlai@gmail.com>
 <20230216235321.735214-1-jiangshanlai@gmail.com>
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From: Lai Jiangshan <jiangshan.ljs@antgroup.com>

Don't assume the current root to be valid, just check it and remove
the WARN().

Also move the code to check if the root is valid into FNAME(invlpg)
to simplify the code.

Signed-off-by: Lai Jiangshan <jiangshan.ljs@antgroup.com>
---
 arch/x86/kvm/mmu/mmu.c         | 3 +--
 arch/x86/kvm/mmu/paging_tmpl.h | 4 +---
 2 files changed, 2 insertions(+), 5 deletions(-)

diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 9b5e3afbcdb4..7d5ff2b0f6d5 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -5786,8 +5786,7 @@ void kvm_mmu_invalidate_addr(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu,
 		mmu->invlpg(vcpu, addr, mmu->root.hpa);
 
 	for (i = 0; i < KVM_MMU_NUM_PREV_ROOTS; i++) {
-		if ((roots & KVM_MMU_ROOT_PREVIOUS(i)) &&
-		    VALID_PAGE(mmu->prev_roots[i].hpa))
+		if (roots & KVM_MMU_ROOT_PREVIOUS(i))
 			mmu->invlpg(vcpu, addr, mmu->prev_roots[i].hpa);
 	}
 }
diff --git a/arch/x86/kvm/mmu/paging_tmpl.h b/arch/x86/kvm/mmu/paging_tmpl.h
index 7db167876cd7..9be5a0f22a9f 100644
--- a/arch/x86/kvm/mmu/paging_tmpl.h
+++ b/arch/x86/kvm/mmu/paging_tmpl.h
@@ -904,10 +904,8 @@ static void FNAME(invlpg)(struct kvm_vcpu *vcpu, u64 addr, hpa_t root_hpa)
 	 */
 	mmu_topup_memory_caches(vcpu, true);
 
-	if (!VALID_PAGE(root_hpa)) {
-		WARN_ON(1);
+	if (!VALID_PAGE(root_hpa))
 		return;
-	}
 
 	write_lock(&vcpu->kvm->mmu_lock);
 	for_each_shadow_entry_using_root(vcpu, root_hpa, addr, iterator) {
-- 
2.19.1.6.gb485710b