From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1792588706; b=J3W0FV9TuqmAwQOpkURTjaslc5hEQfYJG1AE3OdXicbKC006HUx7IA8qN8dQeCc/rNKO ehHnixyIsY0+bgXV9tMtsMFCSJXxgmVMGRBVmisIvu3gEc3Fd7m0elke08mK71sN9SLhR nd4qImFLh2+ixF8EW6eX2PgWnATrFhErXlGBCF92Fwyi7fYiTmM5gmcy/OTVs12PpO6VL a8npLiAUuAT2k+bEWXIaZkWTjczxfzPmRoRCsYVAmqbK1GrLC1mQPqcy8vBtyDqyo7Gta PbdnQrY9A8Sm6lB6UFyZsM+8767vf6oagjobVx3A8NYfWa1IV8c5rvsSmOrEmQNXx/Q== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1792588706; h=Received:DKIM-Signature:Date:From:To:Cc:Subject:Message-ID: References:MIME-Version:Content-Type:Content-Disposition:In-Reply-To; bh=ekCibKv0PWllJqYiwbL8NTR+L8MQ741UG7Kn2SVkZkQ=; b=SrNdeeMzbHMysx2Y0Wcf2zAqWA+/7GJ+i8TK0pndoP+70ZUQ8wWj9zwv3OYjZOKJrMrc 37fojtg2poZFLCa+1lwIjiXYDFp6aRonIlCikeSpMRYdnV+psgtjv5BLRymE6kNVU3fT6 fBat6Ih4JoIz6yJcLk66IjtPpZa/oEE6GwbdWfcm7FRP68Q3FC4rZrae8vN5YYuLKF1gk 1y4LdJn+erda8o29ImrbFBQYRfwdBPt+INc4ytxXT7To9Kuzj1MHhpjZCkfotD/CINXOd Kv4OkYsw2+sSpLokzYuFV5+lQQ0xRK/qOW5PudZ9s7XgJjeWt9DyuuhK1Xt6hZqv7Tg== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=jsr8bwoM; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with UTF8SMTPS id E6863606A319; Wed, 21 Oct 2026 13:18:25 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=jsr8bwoM Received: by smtp.kernel.org (Postfix) with UTF8SMTPSA id 0A3D91F000C4; Wed, 21 Oct 2026 13:18:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1792588705; bh=ekCibKv0PWllJqYiwbL8NTR+L8MQ741UG7Kn2SVkZkQ=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=jsr8bwoM0yi7oKg8wHJk3tffC/dTPOTVs02uNlnkZ4oZWn0IRD9DnECnE5Clx9r6/ ae6V09MG/X3D3cV1QxAnRe59hVNjgMeTeC2l3rixB9FwGLnAcoRuWiBmxiMQRy215D KlFub3OGGxGN1Lj/YXKj9T6VFQl/OwSTT1uEPvEpAYwuf42DB0Qgyo2P3dFeemH39k hSSRslObIuFVGzjPkPQ4TUg8OJ9ci1WSwwH2CMBPyn+Uo5RY4Hp0Nyg09UBj2hEAjf 6SzyPKcXDuv4ynFZgHteRinGWJl/umxFeJ1xORjnZuD73uYifWxgtWFv9KC4EkTUad GjWn5gnUhlygw== Date: Wed, 21 Oct 2026 16:18:21 +0300 From: Jarkko Sakkinen To: Mimi Zohar Cc: Jason Gunthorpe , Yeoreum Yun , Dionna Glaze , Jiri Pirko , linux-coco@lists.linux.dev, linux-kernel@vger.kernel.org, linux-api@vger.kernel.org, x86@kernel.org, kvm@vger.kernel.org, linux-doc@vger.kernel.org, david.quigley@intel.com, lukas@wunner.de, ksinyuk@kernel.org, rodrigo.vivi@intel.com, cedric.xing@intel.com, sameo@meta.com, James.Bottomley@hansenpartnership.com, aik@amd.com, jpiotrowski@nvidia.com, qinkun@google.com, pgonda@google.com, jic23@kernel.org, alistair.francis@wdc.com, ankita@nvidia.com, suzuki.poulose@arm.com, kas@kernel.org, rick.p.edgecombe@intel.com, elena.reshetova@intel.com, dave.hansen@linux.intel.com, sathyanarayanan.kuppuswamy@linux.intel.com, peter.fang@intel.com, roberto.sassu@huawei.com Subject: Re: [PATCH RFC 00/20] attestation: Add a common subsystem and TDX support Message-ID: References: <20261017231007.GP13920@nvidia.com> <20261020140655.GV13920@nvidia.com> <20261020165251.GG3008132@nvidia.com> X-Mailing-List: linux-api@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Wed, Oct 21, 2026 at 08:23:05AM -0400, Mimi Zohar wrote: > On Tue, 2026-10-20 at 13:52 -0300, Jason Gunthorpe wrote: > > On Tue, Oct 20, 2026 at 05:11:03PM +0100, Yeoreum Yun wrote: > > > But, I have a related concern about deferred probing of RoT devices. > > > > > > For example, if TPM probing is deferred until after the attestation > > > subsystem has been initialized, how would the subsystem handle the > > > TPM becoming available later (This is reason for > > > IMA_INIT_LATE_SYNC). > > FYI, this patch set initializes at module_initcall(), not even late_initcall(). > > > I don't think it would be any different, the mechanism for TPM would > > become generalized and apply to any attestation driver. > > > > This series doesn't attempt to do that flow yet, moving ima over and > > dealing with this is another series :) > > When TPM device initialization is deferred, it is retried during > late_initcall(). I don't remember when but I recall that this has been debated a few times and the idea of deferred TPM initialization has never been successful. Just stating the odds :-) Br, Jarkkko