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Date:   Wed, 20 Jan 2021 13:54:26 +0200
From:   Jarkko Sakkinen <jarkko@kernel.org>
To:     Kai Huang <kai.huang@intel.com>
Cc:     linux-sgx@vger.kernel.org, kvm@vger.kernel.org, x86@kernel.org,
        seanjc@google.com, luto@kernel.org, dave.hansen@intel.com,
        haitao.huang@intel.com, pbonzini@redhat.com, bp@alien8.de,
        tglx@linutronix.de, mingo@redhat.com, hpa@zytor.com
Subject: Re: [RFC PATCH v2 05/26] x86/sgx: Introduce virtual EPC for use by
 KVM guests
Message-ID: <YAgZ8lGaafoTXcYF@kernel.org>
References: <cover.1610935432.git.kai.huang@intel.com>
 <4597db567351468c360fc810fff5a8232cb96c4c.1610935432.git.kai.huang@intel.com>
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On Mon, Jan 18, 2021 at 04:26:53PM +1300, Kai Huang wrote:
> From: Sean Christopherson <sean.j.christopherson@intel.com>
> 
> Add a misc device /dev/sgx_virt_epc to allow userspace to allocate "raw"
> EPC without an associated enclave.  The intended and only known use case
> for raw EPC allocation is to expose EPC to a KVM guest, hence the
> virt_epc moniker, virt.{c,h} files and X86_SGX_VIRTUALIZATION Kconfig.

Is /dev/sgx_virt_epc something only usable for KVM, or is there
any thinkable use outside of the KVM context?

/Jarkko