From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 50D11FF885A for ; Tue, 5 May 2026 09:54:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type:MIME-Version:Message-Id:Date:Subject:Cc:To:From:Reply-To: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References:List-Owner; bh=HPmBeuRUnjxLTbWzzJqJjIKPN3IgdEzZH3lJ0YLb1Ug=; b=VLYqHiT1q05TExQVxBMG5OPda9 AAMNavuthDIbxeTsVNzMpMuVwUN5QmxnR/zjWA51v1CHBqCxJf+OaR/+uZDQ/iCQocyOl26gfUA4R Yjmd90rh69T4z4d+jQP2XcZYRvszSTfrsi1K/skmnPUpcWSRAGtQrZPhRXEHoz+dd4CNnUhWf6VX3 aqxU2UXfkIv7LcdE+ml5kQiR6+S02kP7Cs4kIfYIXDIIQZ2nvptKw8EdXQ5MLFuysvRbrNb2hA8X5 DyqU+8EHVgyGyUdzwEhkE/c0cKHyEspUosIsHan9XyP5ItscOqQ/p7cxLNoXIrFeDMyC9/m1xQseg B5jgmYJA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1wKCTr-0000000Fj9I-3RD8; Tue, 05 May 2026 09:54:19 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1wKCTp-0000000Fj7P-2kRo for linux-arm-kernel@lists.infradead.org; Tue, 05 May 2026 09:54:19 +0000 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 84CCD2936; Tue, 5 May 2026 02:54:09 -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 8439C3F836; Tue, 5 May 2026 02:54:11 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1777974854; bh=mZATz5adCxjq+rKLQMa6TL0ztfFjDih5jW0Ffnpg7tA=; h=From:To:Cc:Subject:Date:From; b=OroYeXVbEYXngvWHaW/fKZK/iVp506G7ITZsUT5skzUb/lyh16bF4bNuXqK2hsAk4 KHLBmCmRAo8EyvVyzaTbJ96xJ8EXSV+onS6Gun44JBV9cfTfanJdk/xIyQ/g9mRhv3 0U5EXk7QZoh+tZoy9yfqywFgFvYyeXEhIxggEoJ0= From: Yeoreum Yun To: linux-integrity@vger.kernel.org, keyrings@vger.kernel.org, linux-security-module@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev Cc: jarkko@kernel.org, zohar@linux.ibm.com, roberto.sassu@huawei.com, dmitry.kasatkin@gmail.com, eric.snowberg@oracle.com, paul@paul-moore.com, jmorris@namei.org, serge@hallyn.com, maz@kernel.org, oupton@kernel.org, joey.gouly@arm.com, suzuki.poulose@arm.com, yuzenghui@huawei.com, catalin.marinas@arm.com, will@kernel.org, sudeep.holla@kernel.org, Yeoreum Yun Subject: [RFC PATCH 0/3] initalise ff-a after finalising pKVM Date: Tue, 5 May 2026 10:54:06 +0100 Message-Id: <20260505095409.1948371-1-yeoreum.yun@arm.com> X-Mailer: git-send-email 2.34.1 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260505_025417_808346_3A6D1FF3 X-CRM114-Status: GOOD ( 15.06 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org This patch is split out from the patchset [0] -- fix FF-A call failure with pKVM when the FF-A driver is built-in, specifically the IMA-related part. When pKVM is enabled, the FF-A driver must be initialised after pKVM. Otherwise, pKVM cannot negotiate the FF-A version or obtain the RX/TX buffer information, leading to failures in FF-A calls. Currently, pKVM initialisation completes at device_initcall_sync, while ffa_init() runs at the device_initcall level. So far, linker deployes kvm_arm_init() before ffa_init(), and SMCs can still be trapped even before finalise_pkvm() is invoked. As a result, this issue has not been observed. However, relying on above stuff is fragile. Therefore, when pKVM is enabled, the FF-A infrastructure should be initialised only after pKVM initialisation has been fully finalised. To achieve this, introduce an ffa_root_dev ("arm-ffa") and a corresponding driver to defer initialisation of the FF-A infrastructure until pKVM initialisation is complete, and to defer probing of all FF-A devices until then when pKVM is enabled. This patch is based on v7.1-rc2 Question: FF-A initialisation can occur at late_initcall. Because it may be deferred, some FF-A requests cannot be serviced at that stage. A typical example is the EFI runtime variable service using DIRECT_MSG_REQ. Depending on the platform, the EFI runtime variable service runs with StandaloneMm and uses FF-A DIRECT_REQ. However, when pKVM is enabled, FF-A initialisation may be deferred to late_initcall. In this case, load_uefi_certs() can fail if it is invoked before the FF-A driver is initialised via deferred_probe_initcall(). Moving load_uefi_certs() to late_initcall_sync, as in the third patch, seems not to have any problem since late_initcall and late_initcall_sync are both of do_basic_setup() and it's before loading init process. However, it is still unclear whether it would be better to allow DIRECT_MSG_REQ in kvm_host_ffa_handler() even before FF-A version negotiation since handler’s purpose seems to hook certain memory operations, and DIRECT_MSG_REQ has been available since FF-A specification v1.0. Any feedback or alternative suggestions would be appreciated! Link: https://lore.kernel.org/all/20260422162449.1814615-1-yeoreum.yun@arm.com/ [0] Yeoreum Yun (3): arm64: KVM: defer kvm_init() to finalise_pkvm() when pKVM is enabled firmware: arm_ffa: initialise ff-a after finalising pKVM initialisation security: integrity: call load_uefi_certs() at late_initcall_sync arch/arm64/kvm/arm.c | 8 +- arch/arm64/kvm/pkvm.c | 15 ++- drivers/firmware/arm_ffa/bus.c | 125 +++++++++++++++++- drivers/firmware/arm_ffa/common.h | 13 +- drivers/firmware/arm_ffa/driver.c | 21 ++- drivers/firmware/arm_ffa/smccc.c | 2 +- security/integrity/platform_certs/load_uefi.c | 2 +- 7 files changed, 166 insertions(+), 20 deletions(-) base-commit: 7fd2df204f342fc17d1a0bfcd474b24232fb0f32 -- LEVI:{C3F47F37-75D8-414A-A8BA-3980EC8A46D7}