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From:   isaku.yamahata@intel.com
To:     kvm@vger.kernel.org, linux-kernel@vger.kernel.org
Cc:     isaku.yamahata@intel.com, isaku.yamahata@gmail.com,
        Paolo Bonzini <pbonzini@redhat.com>
Subject: [PATCH v7 043/102] KVM: x86/mmu: Focibly use TDP MMU for TDX
Date:   Mon, 27 Jun 2022 14:53:35 -0700
Message-Id: <c198d2be26aa9a041176826cf86b51a337427783.1656366338.git.isaku.yamahata@intel.com>
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From: Isaku Yamahata <isaku.yamahata@intel.com>

In this patch series, TDX supports only TDP MMU and doesn't support legacy
MMU.  Forcibly use TDP MMU for TDX irrelevant of kernel parameter to
disable TDP MMU.

Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>
---
 arch/x86/kvm/mmu/tdp_mmu.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c
index 82f1bfac7ee6..7eb41b176d1e 100644
--- a/arch/x86/kvm/mmu/tdp_mmu.c
+++ b/arch/x86/kvm/mmu/tdp_mmu.c
@@ -18,8 +18,13 @@ int kvm_mmu_init_tdp_mmu(struct kvm *kvm)
 {
 	struct workqueue_struct *wq;
 
-	if (!tdp_enabled || !READ_ONCE(tdp_mmu_enabled))
-		return 0;
+	/*
+	 *  Because TDX supports only TDP MMU, forcibly use TDP MMU in the case
+	 *  of TDX.
+	 */
+	if (kvm->arch.vm_type != KVM_X86_TDX_VM &&
+		(!tdp_enabled || !READ_ONCE(tdp_mmu_enabled)))
+		return false;
 
 	wq = alloc_workqueue("kvm", WQ_UNBOUND|WQ_MEM_RECLAIM|WQ_CPU_INTENSIVE, 0);
 	if (!wq)
-- 
2.25.1