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Date:   Tue, 5 Apr 2022 14:52:30 +0200
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Subject: Re: [RFC PATCH v5 026/104] KVM: TDX: x86: Add vm ioctl to get TDX
 systemwide parameters
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To:     isaku.yamahata@intel.com, kvm@vger.kernel.org,
        linux-kernel@vger.kernel.org
Cc:     isaku.yamahata@gmail.com, Jim Mattson <jmattson@google.com>,
        erdemaktas@google.com, Connor Kuehl <ckuehl@redhat.com>,
        Sean Christopherson <seanjc@google.com>
References: <cover.1646422845.git.isaku.yamahata@intel.com>
 <5ff08ce32be458581afe59caa05d813d0e4a1ef0.1646422845.git.isaku.yamahata@intel.com>
From:   Paolo Bonzini <pbonzini@redhat.com>
In-Reply-To: <5ff08ce32be458581afe59caa05d813d0e4a1ef0.1646422845.git.isaku.yamahata@intel.com>
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On 3/4/22 20:48, isaku.yamahata@intel.com wrote:
> Implement a VM-scoped subcomment to get system-wide parameters.  Although
> this is system-wide parameters not per-VM, this subcomand is VM-scoped
> because
> - Device model needs TDX system-wide parameters after creating KVM VM.
> - This subcommands requires to initialize TDX module.  For lazy
>    initialization of the TDX module, vm-scope ioctl is better.

Since there was agreement to install the TDX module on load, please 
place this ioctl on the /dev/kvm file descriptor.

At least for SEV, there were cases where the system-wide parameters are 
needed outside KVM, so it's better to avoid requiring a VM file descriptor.

Thanks,

Paolo