From: Paolo Bonzini <pbonzini@redhat.com>
To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org
Cc: seanjc@google.com
Subject: Re: [PATCH 16/22] KVM: x86/mmu: remove redundant bits from extended role
Date: Thu, 14 Apr 2022 10:27:11 +0200 [thread overview]
Message-ID: <166f2025-1479-a5d0-9d0d-da158b01fa95@redhat.com> (raw)
In-Reply-To: <20220414074000.31438-17-pbonzini@redhat.com>
On 4/14/22 09:39, Paolo Bonzini wrote:
> Before the separation of the CPU and the MMU role, CR0.PG was not
> available in the base MMU role, because two-dimensional paging always
> used direct=1 in the MMU role. However, now that the raw role is
> snapshotted in mmu->cpu_role, CR0.PG *can* be found (though inverted)
> as !cpu_role.base.direct. There is no need to store it again in union
> kvm_mmu_extended_role; instead, write an is_cr0_pg accessor by hand that
> takes care of the inversion.
>
> Likewise, CR4.PAE is now always present in the CPU role as
> !cpu_role.base.has_4_byte_gpte. The inversion makes certain tests on
> the MMU role easier, and is easily hidden by the is_cr4_pae accessor
> when operating on the CPU role.
>
> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Better:
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index cf8a41675a79..2a9b589192c3 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -234,7 +234,7 @@ BUILD_MMU_ROLE_ACCESSOR(base, efer, nx);
static inline bool is_cr0_pg(struct kvm_mmu *mmu)
{
- return !mmu->cpu_role.base.direct;
+ return mmu->cpu_role.base.level > 0;
}
static inline bool is_cr4_pae(struct kvm_mmu *mmu)
given that the future of the direct bit is unclear.
Paolo
next prev parent reply other threads:[~2022-04-14 8:27 UTC|newest]
Thread overview: 34+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-04-14 7:39 [PATCH v3 00/22] https://www.spinics.net/lists/kvm/msg267878.html Paolo Bonzini
2022-04-14 7:39 ` [PATCH 01/22] KVM: x86/mmu: nested EPT cannot be used in SMM Paolo Bonzini
2022-04-14 7:39 ` [PATCH 02/22] KVM: x86/mmu: constify uses of struct kvm_mmu_role_regs Paolo Bonzini
2022-04-14 7:39 ` [PATCH 03/22] KVM: x86/mmu: pull computation of kvm_mmu_role_regs to kvm_init_mmu Paolo Bonzini
2022-04-14 7:39 ` [PATCH 04/22] KVM: x86/mmu: rephrase unclear comment Paolo Bonzini
2022-04-14 7:39 ` [PATCH 05/22] KVM: x86: Clean up and document nested #PF workaround Paolo Bonzini
2022-04-14 7:39 ` [PATCH 06/22] KVM: x86/mmu: remove "bool base_only" arguments Paolo Bonzini
2022-04-14 7:39 ` [PATCH 07/22] KVM: x86/mmu: split cpu_role from mmu_role Paolo Bonzini
2022-04-15 4:16 ` Like Xu
2022-04-14 7:39 ` [PATCH 08/22] KVM: x86/mmu: do not recompute root level from kvm_mmu_role_regs Paolo Bonzini
2022-04-14 7:39 ` [PATCH 09/22] KVM: x86/mmu: remove ept_ad field Paolo Bonzini
2022-04-14 7:39 ` [PATCH 10/22] KVM: x86/mmu: remove kvm_calc_shadow_root_page_role_common Paolo Bonzini
2022-04-14 7:39 ` [PATCH 11/22] KVM: x86/mmu: cleanup computation of MMU roles for two-dimensional paging Paolo Bonzini
2022-04-14 7:39 ` [PATCH 12/22] KVM: x86/mmu: cleanup computation of MMU roles for shadow paging Paolo Bonzini
2022-04-14 7:39 ` [PATCH 13/22] KVM: x86/mmu: store shadow EFER.NX in the MMU role Paolo Bonzini
2022-04-14 7:39 ` [PATCH 14/22] KVM: x86/mmu: remove extended bits from mmu_role, rename field Paolo Bonzini
2022-04-14 7:39 ` [PATCH 15/22] KVM: x86/mmu: rename kvm_mmu_role union Paolo Bonzini
2022-04-14 7:39 ` [PATCH 16/22] KVM: x86/mmu: remove redundant bits from extended role Paolo Bonzini
2022-04-14 8:27 ` Paolo Bonzini [this message]
2022-05-10 0:20 ` Sean Christopherson
2022-05-11 13:53 ` Paolo Bonzini
2022-05-12 13:59 ` Paolo Bonzini
2022-05-12 14:18 ` Sean Christopherson
2022-05-12 16:09 ` Paolo Bonzini
2022-05-12 21:34 ` Sean Christopherson
2022-04-14 7:39 ` [PATCH 17/22] KVM: x86/mmu: remove valid " Paolo Bonzini
2022-04-14 7:39 ` [PATCH 18/22] KVM: x86/mmu: simplify and/or inline computation of shadow MMU roles Paolo Bonzini
2022-04-14 7:39 ` [PATCH 19/22] KVM: x86/mmu: pull CPU mode computation to kvm_init_mmu Paolo Bonzini
2022-04-14 7:39 ` [PATCH 20/22] KVM: x86/mmu: replace shadow_root_level with root_role.level Paolo Bonzini
2022-04-14 7:39 ` [PATCH 21/22] KVM: x86/mmu: replace root_level with cpu_role.base.level Paolo Bonzini
2022-04-14 7:40 ` [PATCH 22/22] KVM: x86/mmu: replace direct_map with root_role.direct Paolo Bonzini
2022-04-14 7:47 ` [PATCH v3 00/22] https://www.spinics.net/lists/kvm/msg267878.html Paolo Bonzini
2022-04-14 15:02 ` Sean Christopherson
2022-04-14 15:09 ` Paolo Bonzini
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