From: Sean Christopherson <seanjc@google.com>
To: Sean Christopherson <seanjc@google.com>,
Paolo Bonzini <pbonzini@redhat.com>
Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org,
David Matlack <dmatlack@google.com>,
Isaku Yamahata <isaku.yamahata@intel.com>
Subject: [PATCH v4 07/11] KVM: x86/mmu: Pivot on "TDP MMU enabled" when handling direct page faults
Date: Wed, 12 Oct 2022 18:16:58 +0000 [thread overview]
Message-ID: <20221012181702.3663607-8-seanjc@google.com> (raw)
In-Reply-To: <20221012181702.3663607-1-seanjc@google.com>
When handling direct page faults, pivot on the TDP MMU being globally
enabled instead of checking if the target MMU is a TDP MMU. Now that the
TDP MMU is all-or-nothing, if the TDP MMU is enabled, KVM will reach
direct_page_fault() if and only if the MMU is a TDP MMU. When TDP is
enabled (obviously required for the TDP MMU), only non-nested TDP page
faults reach direct_page_fault(), i.e. nonpaging MMUs are impossible, as
NPT requires paging to be enabled and EPT faults use ept_page_fault().
Signed-off-by: Sean Christopherson <seanjc@google.com>
---
arch/x86/kvm/mmu/mmu.c | 9 ++++-----
1 file changed, 4 insertions(+), 5 deletions(-)
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 5710be4d328b..fe3aa890a487 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -3324,7 +3324,7 @@ static int fast_page_fault(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault)
do {
u64 new_spte;
- if (is_tdp_mmu(vcpu->arch.mmu))
+ if (is_tdp_mmu_enabled())
sptep = kvm_tdp_mmu_fast_pf_get_last_sptep(vcpu, fault->addr, &spte);
else
sptep = fast_pf_get_last_sptep(vcpu, fault->addr, &spte);
@@ -4252,7 +4252,6 @@ static bool is_page_fault_stale(struct kvm_vcpu *vcpu,
static int direct_page_fault(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault)
{
- bool is_tdp_mmu_fault = is_tdp_mmu(vcpu->arch.mmu);
int r;
fault->gfn = fault->addr >> PAGE_SHIFT;
@@ -4275,7 +4274,7 @@ static int direct_page_fault(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault
r = RET_PF_RETRY;
- if (is_tdp_mmu_fault)
+ if (is_tdp_mmu_enabled())
read_lock(&vcpu->kvm->mmu_lock);
else
write_lock(&vcpu->kvm->mmu_lock);
@@ -4287,13 +4286,13 @@ static int direct_page_fault(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault
if (r)
goto out_unlock;
- if (is_tdp_mmu_fault)
+ if (is_tdp_mmu_enabled())
r = kvm_tdp_mmu_map(vcpu, fault);
else
r = __direct_map(vcpu, fault);
out_unlock:
- if (is_tdp_mmu_fault)
+ if (is_tdp_mmu_enabled())
read_unlock(&vcpu->kvm->mmu_lock);
else
write_unlock(&vcpu->kvm->mmu_lock);
--
2.38.0.rc1.362.ged0d419d3c-goog
next prev parent reply other threads:[~2022-10-12 18:18 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-10-12 18:16 [PATCH v4 00/11] KVM: x86/mmu: Make tdp_mmu a read-only parameter Sean Christopherson
2022-10-12 18:16 ` [PATCH v4 01/11] KVM: x86/mmu: Change tdp_mmu to " Sean Christopherson
2022-10-12 21:37 ` Huang, Kai
2022-10-12 18:16 ` [PATCH v4 02/11] KVM: x86/mmu: Move TDP MMU VM init/uninit behind tdp_mmu_enabled Sean Christopherson
2022-10-12 18:16 ` [PATCH v4 03/11] KVM: x86/mmu: Grab mmu_invalidate_seq in kvm_faultin_pfn() Sean Christopherson
2022-10-12 18:16 ` [PATCH v4 04/11] KVM: x86/mmu: Handle error PFNs " Sean Christopherson
2022-10-12 18:16 ` [PATCH v4 05/11] KVM: x86/mmu: Avoid memslot lookup during KVM_PFN_ERR_HWPOISON handling Sean Christopherson
2022-10-12 18:16 ` [PATCH v4 06/11] KVM: x86/mmu: Handle no-slot faults in kvm_faultin_pfn() Sean Christopherson
2022-10-12 18:16 ` Sean Christopherson [this message]
2022-10-12 18:16 ` [PATCH v4 08/11] KVM: x86/mmu: Pivot on "TDP MMU enabled" to check if active MMU is TDP MMU Sean Christopherson
2022-10-12 18:17 ` [PATCH v4 09/11] KVM: x86/mmu: Replace open coded usage of tdp_mmu_page with is_tdp_mmu_page() Sean Christopherson
2022-10-12 18:17 ` [PATCH v4 10/11] KVM: x86/mmu: Use static key/branches for checking if TDP MMU is enabled Sean Christopherson
2022-10-12 18:17 ` [PATCH v4 11/11] KVM: x86/mmu: Stop needlessly making MMU pages available for TDP MMU Sean Christopherson
2022-10-13 17:21 ` [PATCH v4 00/11] KVM: x86/mmu: Make tdp_mmu a read-only parameter David Matlack
2022-10-13 20:12 ` Sean Christopherson
2022-10-13 22:56 ` David Matlack
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