From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7B2F82EC0A1 for ; Wed, 11 Feb 2026 11:17:47 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770808667; cv=none; b=rmyPGLtjDzly32+MZqw3k13ORE6WtAIZRl3ya3snKrYSji3PhZ9HefJjhD3QN4yBSo00zYjsR6nGqxq5U41vQ0fmfGRIjzw9AH0G/PZ7pPo/pAbpaAd/OOjVxszp79ttMElzIc7FsgKjkSw9WUyATJY+QaXHaBkcEeIjoPwLx80= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770808667; c=relaxed/simple; bh=Jp3G29LRoniDECbxeusFH2bwxbxUW5JNY940z1mEmIY=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=HcwsIl/7rScgGATNdqz5GnObmdWxfP9RfUflrPsiAQtVkToyUVVQr5jZvUG7VNAYHyoP/5Ec3FinFcwIvMuy0NgQPFQQccEJOUfBTLk617TmN8wMfY7iA4kJSaw7HkSOwdlg9/2eDuTwSwjaAiA3ofjZ2LMEMLt2SsTsy9UITS0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=pzXUlPZB; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="pzXUlPZB" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 04873C19421; Wed, 11 Feb 2026 11:17:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1770808667; bh=Jp3G29LRoniDECbxeusFH2bwxbxUW5JNY940z1mEmIY=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=pzXUlPZBgcboC1TJmnM1NsnLpKx93Jkpc2hXzUUGLA0Pzt+kSre0hAaq3tvn6kl6k gHZ6EsfC67kVagKMKMgju8H872hzHVhRdPmi2MtyQshaZeuf9cQcTaIdWSdRuf0VDd 01jq9s4J4HlDiSPuZ78MNcIer4sy3JtqShgOTbAPOdd7kegYnRi9+5BD2biaBvUUhQ FsrPG39TBDFHtGvGZZfxIGLehKxivZskaHhy81YySbUfXfqkKnaWbR4YklYNNcqN9H KkeR0xOxK5+el07snrSpw8ZAzjHLrm2glL4+SKQpYNZHfsyG4s1eLsOk29PkRpJXpk /1MwhVLBYdIlw== Received: from phl-compute-03.internal (phl-compute-03.internal [10.202.2.43]) by mailfauth.phl.internal (Postfix) with ESMTP id 252E1F40068; Wed, 11 Feb 2026 06:17:46 -0500 (EST) Received: from phl-frontend-03 ([10.202.2.162]) by phl-compute-03.internal (MEProxy); Wed, 11 Feb 2026 06:17:46 -0500 X-ME-Sender: X-ME-Received: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgeefgedrtddtgddvtddvgeduucetufdoteggodetrf dotffvucfrrhhofhhilhgvmecuhfgrshhtofgrihhlpdfurfetoffkrfgpnffqhgenuceu rghilhhouhhtmecufedttdenucesvcftvggtihhpihgvnhhtshculddquddttddmnecujf gurhepfffhvfevuffkfhggtggujgesthdtredttddtvdenucfhrhhomhepmfhirhihlhcu ufhhuhhtshgvmhgruhcuoehkrghssehkvghrnhgvlhdrohhrgheqnecuggftrfgrthhtvg hrnhepueeijeeiffekheeffffftdekleefleehhfefhfduheejhedvffeluedvudefgfek necuvehluhhsthgvrhfuihiivgeptdenucfrrghrrghmpehmrghilhhfrhhomhepkhhirh hilhhlodhmvghsmhhtphgruhhthhhpvghrshhonhgrlhhithihqdduieduudeivdeiheeh qddvkeeggeegjedvkedqkhgrsheppehkvghrnhgvlhdrohhrghesshhhuhhtvghmohhvrd hnrghmvgdpnhgspghrtghpthhtohepudegpdhmohguvgepshhmthhpohhuthdprhgtphht thhopehsrghthhihrghnrghrrgihrghnrghnrdhkuhhpphhushifrghmhieslhhinhhugi drihhnthgvlhdrtghomhdprhgtphhtthhopegurghnrdhjrdifihhllhhirghmshesihhn thgvlhdrtghomhdprhgtphhtthhopegurghvvgdrhhgrnhhsvghnsehlihhnuhigrdhinh htvghlrdgtohhmpdhrtghpthhtoheprhhitghkrdhprdgvughgvggtohhmsggvsehinhht vghlrdgtohhmpdhrtghpthhtohepgiekieeskhgvrhhnvghlrdhorhhgpdhrtghpthhtoh eplhhinhhugidqkhgvrhhnvghlsehvghgvrhdrkhgvrhhnvghlrdhorhhgpdhrtghpthht oheplhhinhhugidqtghotghosehlihhsthhsrdhlihhnuhigrdguvghv X-ME-Proxy: Feedback-ID: i10464835:Fastmail Received: by mail.messagingengine.com (Postfix) with ESMTPA; Wed, 11 Feb 2026 06:17:43 -0500 (EST) Date: Wed, 11 Feb 2026 11:17:38 +0000 From: Kiryl Shutsemau To: Kuppuswamy Sathyanarayanan Cc: Dan Williams , Dave Hansen , Rick Edgecombe , 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 Message-ID: References: <20260211001712.1531955-1-sathyanarayanan.kuppuswamy@linux.intel.com> <20260211001712.1531955-4-sathyanarayanan.kuppuswamy@linux.intel.com> Precedence: bulk X-Mailing-List: linux-coco@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline 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