From: Paolo Bonzini <pbonzini@redhat.com>
To: Sean Christopherson <seanjc@google.com>
Cc: Rick P Edgecombe <rick.p.edgecombe@intel.com>,
"kvm@vger.kernel.org" <kvm@vger.kernel.org>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
"michael.roth@amd.com" <michael.roth@amd.com>,
Isaku Yamahata <isaku.yamahata@intel.com>
Subject: Re: [PATCH v5 07/17] KVM: x86: add fields to struct kvm_arch for CoCo features
Date: Tue, 9 Apr 2024 16:43:59 +0200 [thread overview]
Message-ID: <CABgObfZAJ50Z30VzFLdSrQFOEaPxpyFWuvVr1iGogjhs2_+bGA@mail.gmail.com> (raw)
In-Reply-To: <ZhSYEVCHqSOpVKMh@google.com>
On Tue, Apr 9, 2024 at 3:21 AM Sean Christopherson <seanjc@google.com> wrote:
> > I'm a little late to this conversation, so hopefully not just complicating
> > things. But why not deduce has_private_mem and has_protected_state from the
> > vm_type during runtime? Like if kvm.arch.vm_type was instead a bit mask with
> > the bit position of the KVM_X86_*_VM set, kvm_arch_has_private_mem() could
> > bitwise-and with a compile time mask of vm_types that have primate memory.
> > This also prevents it from ever transitioning through non-nonsensical states
> > like vm_type == KVM_X86_TDX_VM, but !has_private_memory, so would be a little
> > more robust.
>
> LOL, time is a circle, or something like that. Paolo actually did this in v2[*],
> and I objected, vociferously.
To be fair, Rick is asking for something much less hideous - just set
kvm->arch.vm_type = (1 << vm_type);
and then define kvm_has_*(kvm) as !!(kvm->arch.vm_type & SOME_BIT_MASK).
And indeed it makes sense as an alternative. It also feels a little
bit more restrictive and the benefit is small, so I think I'm going to
go with this version.
Paolo
next prev parent reply other threads:[~2024-04-09 14:44 UTC|newest]
Thread overview: 31+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-04-04 12:13 [PATCH v5 00/17] KVM: SEV: allow customizing VMSA features Paolo Bonzini
2024-04-04 12:13 ` [PATCH v5 01/17] KVM: SVM: Invert handling of SEV and SEV_ES feature flags Paolo Bonzini
2024-04-04 12:13 ` [PATCH v5 02/17] KVM: SVM: Compile sev.c if and only if CONFIG_KVM_AMD_SEV=y Paolo Bonzini
2024-04-04 12:13 ` [PATCH v5 03/17] KVM: x86: use u64_to_user_ptr() Paolo Bonzini
2024-04-04 12:13 ` [PATCH v5 04/17] KVM: introduce new vendor op for KVM_GET_DEVICE_ATTR Paolo Bonzini
2024-04-04 21:30 ` Isaku Yamahata
2024-04-04 12:13 ` [PATCH v5 05/17] KVM: SEV: publish supported VMSA features Paolo Bonzini
2024-04-04 21:32 ` Isaku Yamahata
2024-04-04 12:13 ` [PATCH v5 06/17] KVM: SEV: store VMSA features in kvm_sev_info Paolo Bonzini
2024-04-04 12:13 ` [PATCH v5 07/17] KVM: x86: add fields to struct kvm_arch for CoCo features Paolo Bonzini
2024-04-04 21:39 ` Isaku Yamahata
2024-04-05 23:01 ` Edgecombe, Rick P
2024-04-09 1:21 ` Sean Christopherson
2024-04-09 14:01 ` Edgecombe, Rick P
2024-04-09 14:43 ` Paolo Bonzini [this message]
2024-04-09 15:26 ` Sean Christopherson
2024-05-07 23:01 ` Edgecombe, Rick P
2024-05-08 0:21 ` Sean Christopherson
2024-05-08 1:19 ` Edgecombe, Rick P
2024-05-08 14:38 ` Sean Christopherson
2024-05-08 15:04 ` Edgecombe, Rick P
2024-04-04 12:13 ` [PATCH v5 08/17] KVM: x86: Add supported_vm_types to kvm_caps Paolo Bonzini
2024-04-04 12:13 ` [PATCH v5 09/17] KVM: SEV: introduce to_kvm_sev_info Paolo Bonzini
2024-04-04 12:13 ` [PATCH v5 10/17] KVM: SEV: define VM types for SEV and SEV-ES Paolo Bonzini
2024-04-04 12:13 ` [PATCH v5 11/17] KVM: SEV: sync FPU and AVX state at LAUNCH_UPDATE_VMSA time Paolo Bonzini
2024-04-04 12:13 ` [PATCH v5 12/17] KVM: SEV: introduce KVM_SEV_INIT2 operation Paolo Bonzini
2024-04-04 12:13 ` [PATCH v5 13/17] KVM: SEV: allow SEV-ES DebugSwap again Paolo Bonzini
2024-04-04 12:13 ` [PATCH v5 14/17] selftests: kvm: add tests for KVM_SEV_INIT2 Paolo Bonzini
2024-04-04 12:13 ` [PATCH v5 15/17] selftests: kvm: switch to using KVM_X86_*_VM Paolo Bonzini
2024-04-04 12:13 ` [PATCH v5 16/17] selftests: kvm: split "launch" phase of SEV VM creation Paolo Bonzini
2024-04-04 12:13 ` [PATCH v5 17/17] selftests: kvm: add test for transferring FPU state into VMSA Paolo Bonzini
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