Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
MIME-Version: 1.0
References: <a507ef3302d3afff58d82528ee17e82df1f21de0.camel@HansenPartnership.com>
 <64c5ed6eb4ca1_a88b2942a@dwillia2-xfh.jf.intel.com.notmuch>
 <c6576d1682b576ba47556478a98f397ed518a177.camel@HansenPartnership.com>
 <64cdb5f25c56_2138e294f1@dwillia2-xfh.jf.intel.com.notmuch>
 <1180481830431165d49c5e64b92b81c396ebc9b1.camel@HansenPartnership.com>
 <64d17f5728fbc_5ea6e2943f@dwillia2-xfh.jf.intel.com.notmuch>
 <c7d6e953a4b36014ea0c7406531b24bb29d6127e.camel@HansenPartnership.com>
 <2425e00b-defb-c12b-03e5-c3d23b30be01@linux.intel.com> <64d263e44e401_2138e29486@dwillia2-xfh.jf.intel.com.notmuch>
 <CAAH4kHamob7g_+BRd0JW76cM7_vS=jzXzRjrgCPDxZ29VnzdCQ@mail.gmail.com> <64d270a2a68ce_5ea6e294f0@dwillia2-xfh.jf.intel.com.notmuch>
In-Reply-To: <64d270a2a68ce_5ea6e294f0@dwillia2-xfh.jf.intel.com.notmuch>
From:   Dionna Amalie Glaze <dionnaglaze@google.com>
Date:   Tue, 8 Aug 2023 10:21:02 -0700
Message-ID: <CAAH4kHYht5s4CkS5Y9+VotPH4WqDrzng0vYy89oq0_U16H_dDA@mail.gmail.com>
Subject: Re: [PATCH 0/4] keys: Introduce a keys frontend for attestation reports
To:     Dan Williams <dan.j.williams@intel.com>
Cc:     Sathyanarayanan Kuppuswamy 
        <sathyanarayanan.kuppuswamy@linux.intel.com>,
        James Bottomley <James.Bottomley@hansenpartnership.com>,
        dhowells@redhat.com, Brijesh Singh <brijesh.singh@amd.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Tom Lendacky <thomas.lendacky@amd.com>,
        Borislav Petkov <bp@alien8.de>,
        Jarkko Sakkinen <jarkko@kernel.org>,
        Samuel Ortiz <sameo@rivosinc.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        linux-coco@lists.linux.dev, keyrings@vger.kernel.org,
        x86@kernel.org, linux-kernel@vger.kernel.org
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

>
> I do not see sysfs precluding a use case like that. If the kernel can
> call out to userspace for TLS connection setup [1], then advanced user
> can call out to a daemon for workload provenance setup. Recall that TDX
> will round trip through the quoting enclave for these reports and,
> without measuring, that seems to have the potential to dominate the
> setup time vs the communication to ask a daemon to convey a report.
>

It's rather hard to get new daemons approved for container
distributions since they end up as resource hogs.
I really don't think it's appropriate to delegate to a daemon to
single-thread use of a kernel interface when the interface could
provide functional semantics to begin with.

> [1]: https://lore.kernel.org/all/168174169259.9520.1911007910797225963.stgit@91.116.238.104.host.secureserver.net/


-- 
-Dionna Glaze, PhD (she/her)