From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id F3094299929; Wed, 22 Apr 2026 19:41:16 +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=1776886880; cv=none; b=gt2KwcU8KdSMkcAmE9y0ZtdlZOxM6mXYUbllQJsCHeXFGFVUqSSC2NSR+FjLoxp0W7+Mz/5Y+kxMYUQGt22twf83usOJiqOQ/Iwl9LF31aLyqcrfN/5LsTCHS2KARxK3eWZ0TPw6vfm+Fz+gM7vB2MkdYt7qVabzsTJjYChdEY4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776886880; c=relaxed/simple; bh=tGo1tyalwnLC7Qix4mlWc2AAj2+tR6uJ/+3oGMxJUVU=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=TRpvvSqjx5H8+JoM9j2PqtzHhfgXhvNud/PypRuc5Gio8imoUO5GA23XYhyq4DA5Yd9gMbBH/BsUzoIeEY1SSCyDFYZYWJezPqmvK6mpX1eITPnRVH3twOV+1LiqMd23AUvVzCxFzU3SxZWBWQ5kYibKZPoEBFoPJ6axoeun9/g= 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; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b=ld27Ctu3; 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 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b="ld27Ctu3" 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 BBCF22F; Wed, 22 Apr 2026 12:41:09 -0700 (PDT) Received: from e129823.arm.com (e129823.arm.com [10.1.197.6]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id DE68F3F7B4; Wed, 22 Apr 2026 12:41:11 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1776886875; bh=tGo1tyalwnLC7Qix4mlWc2AAj2+tR6uJ/+3oGMxJUVU=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=ld27Ctu3LjLwz6nyJncF4IMY20+aIHT/e3N866KLdFOVkS2ybBAVb1fp0IiWooEF7 OTw5J2O+YHnNNRT/B23ikfOGGohqln1hPRtAbFlJWe7BNP2EwNp/Bo/HHtkP+eru/d 3PquYiSxL9s664PGxh/lDrWC43BpYpYW5dJMiK20= Date: Wed, 22 Apr 2026 20:41:09 +0100 From: Yeoreum Yun To: Mimi Zohar Cc: linux-security-module@vger.kernel.org, linux-kernel@vger.kernel.org, linux-integrity@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, paul@paul-moore.com, jmorris@namei.org, serge@hallyn.com, roberto.sassu@huawei.com, dmitry.kasatkin@gmail.com, eric.snowberg@oracle.com, jarkko@kernel.org, jgg@ziepe.ca, sudeep.holla@kernel.org, maz@kernel.org, oupton@kernel.org, joey.gouly@arm.com, suzuki.poulose@arm.com, yuzenghui@huawei.com, catalin.marinas@arm.com, will@kernel.org, noodles@meta.com, sebastianene@google.com Subject: Re: [RFC PATCH v2 1/4] security: ima: call ima_init() again at late_initcall_sync for defered TPM Message-ID: References: <20260422162449.1814615-1-yeoreum.yun@arm.com> <20260422162449.1814615-2-yeoreum.yun@arm.com> <6919248bdc85dac60277fa9d9c83d8bd258ca635.camel@linux.ibm.com> Precedence: bulk X-Mailing-List: linux-security-module@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: > Hi Mimi, > > > On Wed, 2026-04-22 at 17:24 +0100, Yeoreum Yun wrote: > > > To generate the boot_aggregate log in the IMA subsystem with TPM PCR values, > > > the TPM driver must be built as built-in and > > > must be probed before the IMA subsystem is initialized. > > > > > > However, when the TPM device operates over the FF-A protocol using > > > the CRB interface, probing fails and returns -EPROBE_DEFER if > > > the tpm_crb_ffa device — an FF-A device that provides the communication > > > interface to the tpm_crb driver — has not yet been probed. > > > > > > To ensure the TPM device operating over the FF-A protocol with > > > the CRB interface is probed before IMA initialization, > > > the following conditions must be met: > > > > > > 1. The corresponding ffa_device must be registered, > > > which is done via ffa_init(). > > > > > > 2. The tpm_crb_driver must successfully probe this device via > > > tpm_crb_ffa_init(). > > > > > > 3. The tpm_crb driver using CRB over FF-A can then > > > be probed successfully. (See crb_acpi_add() and > > > tpm_crb_ffa_init() for reference.) > > > > > > Unfortunately, ffa_init(), tpm_crb_ffa_init(), and crb_acpi_driver_init() are > > > all registered with device_initcall, which means crb_acpi_driver_init() may > > > be invoked before ffa_init() and tpm_crb_ffa_init() are completed. > > > > > > When this occurs, probing the TPM device is deferred. > > > However, the deferred probe can happen after the IMA subsystem > > > has already been initialized, since IMA initialization is performed > > > during late_initcall, and deferred_probe_initcall() is performed > > > at the same level. > > > > > > To resolve this, call ima_init() again at late_inicall_sync level > > > so that let IMA not miss TPM PCR value when generating boot_aggregate > > > log though TPM device presents in the system. > > > > > > Signed-off-by: Yeoreum Yun > > > > A lot of change for just detecting whether ima_init() is being called on > > late_initcall or late_initcall_sync(), without any explanation for all the other > > changes (e.g. ima_init_core). > > > > Please just limit the change to just calling ima_init() twice. > > My concern is that ima_update_policy_flags() will be called > when ima_init() is deferred -- not initialised anything. > though functionally, it might be okay however, > I think ima_update_policy_flags() and notifier should work after ima_init() > works logically. > > This change I think not much quite a lot. just wrapper ima_init() with > ima_init_core() with some error handling. > > Am I missing something? Also, if we handle in ima_init() only, but it failed with other reason, we shouldn't call again ima_init() in the late_initcall_sync. To handle this, It wouldn't do in the ima_init() but we need to handle it by caller of ima_init(). -- Sincerely, Yeoreum Yun