From patchwork Fri Aug 20 14:47:22 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marc Zyngier X-Patchwork-Id: 500555 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-17.0 required=3.0 tests=BAYES_00, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 766A1C4338F for ; Fri, 20 Aug 2021 14:47:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5E69061057 for ; Fri, 20 Aug 2021 14:47:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240923AbhHTOsG (ORCPT ); Fri, 20 Aug 2021 10:48:06 -0400 Received: from mail.kernel.org ([198.145.29.99]:44558 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240894AbhHTOsG (ORCPT ); Fri, 20 Aug 2021 10:48:06 -0400 Received: from disco-boy.misterjones.org (disco-boy.misterjones.org [51.254.78.96]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 30D6B61101; Fri, 20 Aug 2021 14:47:28 +0000 (UTC) Received: from sofa.misterjones.org ([185.219.108.64] helo=hot-poop.lan) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1mH5nq-006D0z-1S; Fri, 20 Aug 2021 15:47:26 +0100 From: Marc Zyngier To: linux-kernel@vger.kernel.org, devicetree@vger.kernel.org Cc: frowand.list@gmail.com, robh+dt@kernel.org, kernel-team@android.com Subject: [PATCH] of: Don't allow __of_attached_node_sysfs() without CONFIG_SYSFS Date: Fri, 20 Aug 2021 15:47:22 +0100 Message-Id: <20210820144722.169226-1-maz@kernel.org> X-Mailer: git-send-email 2.30.2 MIME-Version: 1.0 X-SA-Exim-Connect-IP: 185.219.108.64 X-SA-Exim-Rcpt-To: linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, frowand.list@gmail.com, robh+dt@kernel.org, kernel-team@android.com X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org Trying to boot without SYSFS, but with OF_DYNAMIC quickly results in a crash: [ 0.088460] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000070 [...] [ 0.103927] CPU: 1 PID: 1 Comm: swapper/0 Not tainted 5.14.0-rc3 #4179 [ 0.105810] Hardware name: linux,dummy-virt (DT) [ 0.107147] pstate: 80000005 (Nzcv daif -PAN -UAO -TCO BTYPE=--) [ 0.108876] pc : kernfs_find_and_get_ns+0x3c/0x7c [ 0.110244] lr : kernfs_find_and_get_ns+0x3c/0x7c [...] [ 0.134087] Call trace: [ 0.134800] kernfs_find_and_get_ns+0x3c/0x7c [ 0.136054] safe_name+0x4c/0xd0 [ 0.136994] __of_attach_node_sysfs+0xf8/0x124 [ 0.138287] of_core_init+0x90/0xfc [ 0.139296] driver_init+0x30/0x4c [ 0.140283] kernel_init_freeable+0x160/0x1b8 [ 0.141543] kernel_init+0x30/0x140 [ 0.142561] ret_from_fork+0x10/0x18 While not having sysfs isn't a very common option these days, it is still expected that such configuration would work. Paper over it by bailing out from __of_attach_node_sysfs() if CONFIG_SYSFS isn't enabled. Signed-off-by: Marc Zyngier --- drivers/of/kobj.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/of/kobj.c b/drivers/of/kobj.c index a32e60b024b8..6675b5e56960 100644 --- a/drivers/of/kobj.c +++ b/drivers/of/kobj.c @@ -119,7 +119,7 @@ int __of_attach_node_sysfs(struct device_node *np) struct property *pp; int rc; - if (!of_kset) + if (!IS_ENABLED(CONFIG_SYSFS) || !of_kset) return 0; np->kobj.kset = of_kset;