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 6E84FFED9EA for ; Tue, 17 Mar 2026 16:21:07 +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:In-Reply-To:From:References:Cc:To:Subject:MIME-Version:Date: Message-ID:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=dPLJvT/O3xjlhUzGaaqaIFKbRVcKhxs5Q2ocmQ1KpYQ=; b=EvLmm4+u75Lkeqb+Ot89Enwq6/ fEazYaQNu80KJ44NKreUyDYiCiL4g35eqkvCmGVRywz/NQuLlhKv/oint6XWIZswXzN7h6yUv2xZZ wdDsVbcDofg1VuUdad7kf76ltOV/zfrdHHlLUJbuT/U/RcMgpl6GcrqNIpjTaBi5dos1hmfx3TxoK i1ssmze9qnQvvVq7Sihnun/lvmeiCBuUA2i92/8jXQKjz80rMSWfVGWOERMwfdd65vifnvQG2NQGp T4/EVPXNErU4iwhNT72Cj7zJv9b5BDGnOCLRkXq0W8+HKiMpQe/8BD0rXJRNgpCwpZ/kU1qCJv2rD /we1GjKQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1w2XAF-00000006oO7-0xva; Tue, 17 Mar 2026 16:21:03 +0000 Received: from sea.source.kernel.org ([2600:3c0a:e001:78e:0:1991:8:25]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1w2XAD-00000006oNE-04A4 for linux-arm-kernel@lists.infradead.org; Tue, 17 Mar 2026 16:21:02 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by sea.source.kernel.org (Postfix) with ESMTP id B5FC740BAF; Tue, 17 Mar 2026 16:20:58 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 775A7C4CEF7; Tue, 17 Mar 2026 16:20:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1773764458; bh=e0BPQ1p0UdfRCxCsTaN9DCxBuEgVgdYt0iMgNM1/M1A=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=KWwY5lgxEUOSMGbdv+aQWxJp08HLMO7z3TQgBQ1a0RAkOkA+HhoC66RreUnEdoqVv f/Cj0g3xYmLRHrgQZGCWbPRlyy12meMkzl61LsRz54Zu073r6Ct7QpcsIhxHEwwEYd tpszZOw4aqVoCCSO8A1hDIi7Cx2lQ1cniaOFqORXExZjrvwcId9xfPi9od081znGp0 j3AlD3Vxh84yMQGKBBsYSIgnfRb2FPxk0OmYjc2c+6MctKviHVjF5wfUby36SiQxnP zVQJz5jotHJhQosIBbAGv0xdxeJq969llKUbN+YrfDoOUB7H3IvqF6IK1UiyqIqhT+ ThoDGXHmVugpA== Message-ID: <0f92ab73-5996-4977-9ada-e8a26957110c@kernel.org> Date: Tue, 17 Mar 2026 17:20:51 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2] device property: Make modifications of fwnode "flags" thread safe To: "Rafael J. Wysocki" Cc: Douglas Anderson , Greg Kroah-Hartman , stable@vger.kernel.org, Andy Shevchenko , Mark Brown , Wolfram Sang , Andrew Lunn , Daniel Scally , "David S. Miller" , Eric Dumazet , Fabio Estevam , Frank Li , Heikki Krogerus , Heiner Kallweit , Jakub Kicinski , Len Brown , Paolo Abeni , Pengutronix Kernel Team , Rob Herring , Russell King , Sakari Ailus , Saravana Kannan , Sascha Hauer , devicetree@vger.kernel.org, driver-core@lists.linux.dev, imx@lists.linux.dev, linux-acpi@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org, linux-spi@vger.kernel.org, netdev@vger.kernel.org References: <20260317090112.v2.1.I0a4d03104ecd5103df3d76f66c8d21b1d15a2e38@changeid> From: Danilo Krummrich Content-Language: en-US In-Reply-To: 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-20260317_092101_078751_3340BF36 X-CRM114-Status: GOOD ( 11.13 ) 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 On 3/17/2026 5:11 PM, Rafael J. Wysocki wrote: > On Tue, Mar 17, 2026 at 5:04 PM Douglas Anderson wrote: >> >> In various places in the kernel, we modify the fwnode "flags" member >> by doing either: >> fwnode->flags |= SOME_FLAG; >> fwnode->flags &= ~SOME_FLAG; >> >> This type of modification is not thread-safe. If two threads are both >> mucking with the flags at the same time then one can clobber the >> other. >> >> While flags are often modified while under the "fwnode_link_lock", >> this is not universally true. >> >> Create some accessor functions for setting, clearing, and testing the >> FWNODE flags and move all users to these accessor functions. New >> accessor functions use set_bit() and clear_bit(), which are >> thread-safe. >> >> Cc: stable@vger.kernel.org >> Fixes: c2c724c868c4 ("driver core: Add fw_devlink_parse_fwtree()") >> Reviewed-by: Andy Shevchenko >> Acked-by: Mark Brown >> Reviewed-by: Wolfram Sang >> Signed-off-by: Douglas Anderson > > Rafael J. Wysocki (Intel) ACK or RB?