From: Kiryl Shutsemau <kas@kernel.org>
To: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>,
Dave Hansen <dave.hansen@linux.intel.com>,
Rick Edgecombe <rick.p.edgecombe@intel.com>,
x86@kernel.org, linux-kernel@vger.kernel.org,
linux-coco@lists.linux.dev
Subject: Re: [PATCH v1 3/3] virt: tdx-guest: Increase Quote buffer size to 128KB
Date: Wed, 11 Feb 2026 11:17:38 +0000 [thread overview]
Message-ID: <aYxjhdES2MOI7rj9@thinkstation> (raw)
In-Reply-To: <20260211001712.1531955-4-sathyanarayanan.kuppuswamy@linux.intel.com>
On Tue, Feb 10, 2026 at 04:17:12PM -0800, Kuppuswamy Sathyanarayanan wrote:
> Intel platforms are transitioning from traditional SGX-based
> attestation toward DICE-based attestation as part of a broader move
> toward open and standardized attestation models. DICE enables layered
> and extensible attestation, where evidence is accumulated across
> multiple boot stages.
>
> With SGX-based attestation, Quote sizes are typically under 8KB, as the
> payload consists primarily of Quote data and a small certificate bundle.
> Existing TDX guest code sizes the Quote buffer accordingly.
>
> DICE-based attestation produces significantly larger Quotes due to the
> inclusion of evidence (certificate chains) from multiple boot layers.
> The cumulative Quote size can reach approximately 100KB.
>
> Increase GET_QUOTE_BUF_SIZE to 128KB to ensure sufficient buffer
> capacity for DICE-based Quote payloads.
It worth noting that it requires guest physically-contiguous memory.
Single order-5 allocation is not that bad as long as the driver
initialized during the boot.
--
Kiryl Shutsemau / Kirill A. Shutemov
next prev parent reply other threads:[~2026-02-11 11:17 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-02-11 0:17 [PATCH v1 0/3] Increase CoCo attestation report buffer size Kuppuswamy Sathyanarayanan
2026-02-11 0:17 ` [PATCH v1 1/3] virt: tsm: Document size limits for outblob attributes Kuppuswamy Sathyanarayanan
2026-02-11 2:15 ` dan.j.williams
2026-02-11 16:40 ` Kuppuswamy Sathyanarayanan
2026-02-11 20:48 ` dan.j.williams
2026-02-11 0:17 ` [PATCH v1 2/3] virt: tsm: Increase TSM_REPORT_OUTBLOB_MAX to 16MB Kuppuswamy Sathyanarayanan
2026-02-11 2:16 ` dan.j.williams
2026-02-11 0:17 ` [PATCH v1 3/3] virt: tdx-guest: Increase Quote buffer size to 128KB Kuppuswamy Sathyanarayanan
2026-02-11 2:19 ` dan.j.williams
2026-02-11 11:17 ` Kiryl Shutsemau [this message]
2026-02-11 18:40 ` Kuppuswamy Sathyanarayanan
2026-02-11 21:06 ` dan.j.williams
2026-02-11 21:13 ` Kuppuswamy Sathyanarayanan
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=aYxjhdES2MOI7rj9@thinkstation \
--to=kas@kernel.org \
--cc=dan.j.williams@intel.com \
--cc=dave.hansen@linux.intel.com \
--cc=linux-coco@lists.linux.dev \
--cc=linux-kernel@vger.kernel.org \
--cc=rick.p.edgecombe@intel.com \
--cc=sathyanarayanan.kuppuswamy@linux.intel.com \
--cc=x86@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox