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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D291BC4332F for ; Wed, 19 Oct 2022 13:06:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232908AbiJSNGW (ORCPT ); Wed, 19 Oct 2022 09:06:22 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34008 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232818AbiJSNGI (ORCPT ); Wed, 19 Oct 2022 09:06:08 -0400 Received: from pandora.armlinux.org.uk (pandora.armlinux.org.uk [IPv6:2001:4d48:ad52:32c8:5054:ff:fe00:142]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 658131C117F; Wed, 19 Oct 2022 05:50:15 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=armlinux.org.uk; s=pandora-2019; h=Sender:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=0fsK06XH6eOz8QUYu7W6haCyhqbOJ3WnbeWYAL5slVo=; b=pXNf/TpCCzgHcbe302KXLuoY7+ 8Y/jFPJ4a4iKo5bMujxGTdL82eq5duKQVc/eXLuh1S85tm7iEza7H7XPeqm3EehVYbt7FNdBveqB8 CyrFEthXrArT8/uPCt7zKGMFyML0Y+Hgp/tTExGAqYmyNHAIZ+wqogCcyTXWKLyFIo4rdnAO2DDL9 ekr6JFNSkwDWW0ZmQS9xO/Dqm35W7iyL8ovtm3l2sb4HlqcaHYCXuENhNrcZk+xY8Bg0LvkU0o5zr 0si6evLOEWm2iK+LCl/7WgFhMhA+Nwd4zqP1bmDmQ7TV86V44ZaJ24pyh8eaE7ZsouNPxAbxMAQxv SDNqcQYA==; Received: from shell.armlinux.org.uk ([fd8f:7570:feb6:1:5054:ff:fe00:4ec]:34802) by pandora.armlinux.org.uk with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1ol8Vo-0005fg-Oh; Wed, 19 Oct 2022 13:49:33 +0100 Received: from linux by shell.armlinux.org.uk with local (Exim 4.94.2) (envelope-from ) id 1ol8Vk-0002AK-MA; Wed, 19 Oct 2022 13:49:28 +0100 Date: Wed, 19 Oct 2022 13:49:28 +0100 From: "Russell King (Oracle)" To: Clark Wang Cc: peppe.cavallaro@st.com, alexandre.torgue@foss.st.com, joabreu@synopsys.com, davem@davemloft.net, edumazet@google.com, kuba@kernel.org, pabeni@redhat.com, mcoquelin.stm32@gmail.com, netdev@vger.kernel.org, linux-stm32@st-md-mailman.stormreply.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-imx@nxp.com Subject: Re: [PATCH] net: stmmac: linkup phy after enabled mac when system resume Message-ID: References: <20221019123643.1937889-1-xiaoning.wang@nxp.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20221019123643.1937889-1-xiaoning.wang@nxp.com> Sender: Russell King (Oracle) Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Wed, Oct 19, 2022 at 08:36:43PM +0800, Clark Wang wrote: > + mutex_unlock(&priv->lock); > + if (device_may_wakeup(priv->device) && priv->plat->pmt) { > + phylink_resume(priv->phylink); > + } else { > + phylink_resume(priv->phylink); > + if (device_may_wakeup(priv->device)) > + phylink_speed_up(priv->phylink); > + } > + mutex_lock(&priv->lock); First, is there a reason this isn't coded as: mutex_unlock(&priv->lock); phylink_resume(priv->phylink); if (!priv->plat->pmt && device_may_wakeup(priv->device)) phylink_speed_up(priv->phylink); mutex_lock(&priv->lock); And secondly, is it really safe to drop this lock? What specifically is the lock protecting? I see this isn't documented in the driver... -- RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ FTTP is here! 40Mbps down 10Mbps up. Decent connectivity at last!