From nobody Fri Dec 19 20:55:00 2025 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id C15762882A2; Fri, 6 Jun 2025 10:58:01 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1749207483; cv=none; b=aMO6JFfdu2s1fFpA7Z2t2d2gnH/ZIAQQ+S2HNQ3ciUS5CwPbT2NkP36GGnwQ5mnVKFzfQzctEH+fcb0wyMsUklSFe2KyHI6OHOvtz4DMJrG8+COBcu/WniLYw0lK73A/WDAccxbyUHa/asUWNH3oxLbYAAf0cG5lHDL3EkWZ4K0= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1749207483; c=relaxed/simple; bh=LdC86cJWlp6U1sDvJ8jk50YwXi2SHmaCJx6IuM9Udl8=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=dFJV0O024QEK2IY82PCMg4gXpWMNQp/uvncAMiB1UVEbRsL2/cmD2pQSgjGL/MwcTQbkStZgDrro2LiCf0ZVQblb0mOT++4n/gY0TqaqkUrirveJonkErVP9pI7oscz8/trlnvqp4x1TYzLXvG03esrX31aQ1PQj+8jCTL5KLas= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 40E4A1BD0; Fri, 6 Jun 2025 03:57:43 -0700 (PDT) Received: from e129823.cambridge.arm.com (e129823.arm.com [10.1.197.6]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id AA4313F59E; Fri, 6 Jun 2025 03:57:59 -0700 (PDT) From: Yeoreum Yun To: sudeep.holla@arm.com, peterhuewe@gmx.de, jarkko@kernel.org, jgg@ziepe.ca, stuart.yoder@arm.com Cc: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-integrity@vger.kernel.org, Yeoreum Yun Subject: [PATCH 2/2] tpm: tpm_crb_ffa: maunally register tpm_crb_ffa driver when it's built-in Date: Fri, 6 Jun 2025 11:57:54 +0100 Message-Id: <20250606105754.1202649-3-yeoreum.yun@arm.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20250606105754.1202649-1-yeoreum.yun@arm.com> References: <20250606105754.1202649-1-yeoreum.yun@arm.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" To integrate tpm_event_log with IMA subsystem, tpm_crb and tpm_crb_ffa driver should be built as built-in (CONFIG_TCG_CRB=3Dy && CONFIG_TCG_CRB_FFA=3Dy). However, this could make failure for ima_init() gets tpm chip when each initcall function deployed like: 0000000000000888 l .initcall6.init 0000000000000000 crb_acpi_driver_i= nit 000000000000088c l .initcall6.init 0000000000000000 tpm_crb_ffa_drive= r_init If crb_api_driver_init() is called first, probing tpm device using CRB over FFA method is deferred since tpm_crb_ffa_driver_init() isn't called yet. Deferred probe of the tpm device will be probed by system workqueue in proper time after deferred_probe_initcall() registers the work. However, ima_init() could be called first if they're deployed like: 000000000000012c l .initcall7.init 0000000000000000 init_ima 000000000000016c l .initcall7.init 0000000000000000 deferred_probe_in= itcall7 In this situation, ima_init() failed to find tpm device and it failed to generate boot_aggregate with PCR values. That's why kernel prints log this situation though tpm device exists: [ 3.080786] ima: No TPM chip found, activating TPM-bypass! To resolve this, call ffa_register() in tpm_crb_ffa_init() when it was built with built-in so that ima can generate boot_aggregate log with PCR values properly. Signed-off-by: Yeoreum Yun --- drivers/char/tpm/tpm_crb_ffa.c | 22 +++++++++++++++++----- 1 file changed, 17 insertions(+), 5 deletions(-) diff --git a/drivers/char/tpm/tpm_crb_ffa.c b/drivers/char/tpm/tpm_crb_ffa.c index 4ead61f01299..2ef29b66fa5d 100644 --- a/drivers/char/tpm/tpm_crb_ffa.c +++ b/drivers/char/tpm/tpm_crb_ffa.c @@ -115,6 +115,7 @@ struct tpm_crb_ffa { }; =20 static struct tpm_crb_ffa *tpm_crb_ffa; +static struct ffa_driver tpm_crb_ffa_driver; =20 static int tpm_crb_ffa_to_linux_errno(int errno) { @@ -168,13 +169,22 @@ static int tpm_crb_ffa_to_linux_errno(int errno) */ int tpm_crb_ffa_init(void) { - if (!tpm_crb_ffa) - return -ENOENT; + int ret =3D 0; =20 - if (IS_ERR_VALUE(tpm_crb_ffa)) - return -ENODEV; + if (IS_MODULE(CONFIG_TCG_ARM_CRB_FFA)) { + if (!tpm_crb_ffa) + ret =3D -ENOENT; =20 - return 0; + if (IS_ERR_VALUE(tpm_crb_ffa)) + ret =3D -ENODEV; + + return ret; + } + + ret =3D ffa_register(&tpm_crb_ffa_driver); + BUG_ON(!ret && !tpm_crb_ffa); + + return ret; } EXPORT_SYMBOL_GPL(tpm_crb_ffa_init); =20 @@ -369,7 +379,9 @@ static struct ffa_driver tpm_crb_ffa_driver =3D { .id_table =3D tpm_crb_ffa_device_id, }; =20 +#ifdef MODULE module_ffa_driver(tpm_crb_ffa_driver); +#endif =20 MODULE_AUTHOR("Arm"); MODULE_DESCRIPTION("TPM CRB FFA driver"); --=20 LEVI:{C3F47F37-75D8-414A-A8BA-3980EC8A46D7}