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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>, erdemaktas@google.com,
        Sean Christopherson <seanjc@google.com>,
        Sagi Shahar <sagis@google.com>,
        David Matlack <dmatlack@google.com>,
        Kai Huang <kai.huang@intel.com>,
        Zhi Wang <zhi.wang.linux@gmail.com>, chen.bo@intel.com,
        hang.yuan@intel.com, tina.zhang@intel.com,
        Xiaoyao Li <xiaoyao.li@intel.com>
Subject: [RFC PATCH v4 01/16] KVM: TDP_MMU: Go to next level if smaller private mapping exists
Date:   Tue, 25 Jul 2023 15:23:47 -0700
Message-Id: <b263e32affd62ddd675ae50981a4ae3ef7b3c607.1690323516.git.isaku.yamahata@intel.com>
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From: Xiaoyao Li <xiaoyao.li@intel.com>

Cannot map a private page as large page if any smaller mapping exists.

It has to wait for all the not-mapped smaller page to be mapped and
promote it to larger mapping.

Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com>
Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>
---
 arch/x86/kvm/mmu/tdp_mmu.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c
index 95ba78944712..a9f0f4ade2d0 100644
--- a/arch/x86/kvm/mmu/tdp_mmu.c
+++ b/arch/x86/kvm/mmu/tdp_mmu.c
@@ -1293,7 +1293,8 @@ int kvm_tdp_mmu_map(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault)
 	tdp_mmu_for_each_pte(iter, mmu, is_private, raw_gfn, raw_gfn + 1) {
 		int r;
 
-		if (fault->nx_huge_page_workaround_enabled)
+		if (fault->nx_huge_page_workaround_enabled ||
+		    kvm_gfn_shared_mask(vcpu->kvm))
 			disallowed_hugepage_adjust(fault, iter.old_spte, iter.level);
 
 		/*
-- 
2.25.1