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 0DC7ECA1002 for ; Thu, 4 Sep 2025 12:32:55 +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=ZFFCk3oD5mOkAzLuXB6XLVMdJMHaibq0TJviAsZVl/c=; b=FIVZnMHIBHdp32iiE68s4gxEiG P/BMg6FV3q7Gs5oMzeMKlT24BSYSgovEg5uXMCmRceehZnSHBvpwCc5SLIS9fSX3roPrNpNDhUp3k qfVYwzC21MZsr+4wq9H2EIUkbdKUWyRM2UYkm2YOaFpUqV2S3Enmbl3ZC5qqZUWbHgoEfl6Fn7nnm E+pOb9H9evF91ArldYZJl1dm2Xsz5iqHGg9mpfhg9ZZ2TCfBR7CQDYfOESTgdHPV3BHlZFWMLr4oZ MYrjheQg43ww3igXq1ICfqEC0HX+Oml83rAhufVfS2TFHJWVe/4AUO9DAVLEJXprISqYrhwniZp87 PHTMW8pA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1uu98z-0000000BaaL-1bg4; Thu, 04 Sep 2025 12:32:49 +0000 Received: from mail-m49201.qiye.163.com ([45.254.49.201]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1uu7kJ-0000000B4xF-1qbR; Thu, 04 Sep 2025 11:03:16 +0000 Received: from [172.16.12.153] (unknown [58.22.7.114]) by smtp.qiye.163.com (Hmail) with ESMTP id 21b2ed1f3; Thu, 4 Sep 2025 19:03:11 +0800 (GMT+08:00) Message-ID: Date: Thu, 4 Sep 2025 19:03:10 +0800 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH net] net: stmmac: dwmac-rk: Ensure clk_phy doesn't contain invalid address To: "Russell King (Oracle)" , Yao Zi Cc: Andrew Lunn , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Jonas Karlman , David Wu , netdev@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-rockchip@lists.infradead.org References: <20250904031222.40953-3-ziyao@disroot.org> Content-Language: en-US From: Chaoyi Chen In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-HM-Tid: 0a991465108003abkunm0f56a227434cd4 X-HM-MType: 1 X-HM-Spam-Status: e1kfGhgUHx5ZQUpXWQgPGg8OCBgUHx5ZQUlOS1dZFg8aDwILHllBWSg2Ly tZV1koWUFDSUNOT01LS0k3V1ktWUFJV1kPCRoVCBIfWUFZQxhDQlZLGR4dShpIS0pDQkxWFRQJFh oXVRMBExYaEhckFA4PWVdZGBILWUFZTkNVSUlVTFVKSk9ZV1kWGg8SFR0UWUFZT0tIVUpLSU9PT0 hVSktLVUpCS0tZBg++ DKIM-Signature: a=rsa-sha256; b=Xit9gLr6c2F67gZWiRJ3knK+6v3aqUFhgRcIQ2qpT3IVYWVLjxjDx+93FZxit8MYIQ2q4QDexxikifP7ohn/GuR6WZl8TXLXN7BsZSF1phcaUvWq4h0bSxKVFlB7oNT+jkw/9A/nyTQILFNQSy4ZP7NbYAiYNyjQ3WrTJxtEWzs=; c=relaxed/relaxed; s=default; d=rock-chips.com; v=1; bh=ZFFCk3oD5mOkAzLuXB6XLVMdJMHaibq0TJviAsZVl/c=; h=date:mime-version:subject:message-id:from; X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250904_040315_648925_1E4AF7DA X-CRM114-Status: GOOD ( 21.60 ) 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 9/4/2025 6:58 PM, Russell King (Oracle) wrote: > On Thu, Sep 04, 2025 at 03:12:24AM +0000, Yao Zi wrote: >> if (plat->phy_node) { >> bsp_priv->clk_phy = of_clk_get(plat->phy_node, 0); >> ret = PTR_ERR_OR_ZERO(bsp_priv->clk_phy); >> - /* If it is not integrated_phy, clk_phy is optional */ >> + /* >> + * If it is not integrated_phy, clk_phy is optional. But we must >> + * set bsp_priv->clk_phy to NULL if clk_phy isn't proivded, or >> + * the error code could be wrongly taken as an invalid pointer. >> + */ > I'm concerned by this. This code is getting the first clock from the DT > description of the PHY. We don't know what type of PHY it is, or what > the DT description of that PHY might suggest that the first clock would > be. > > However, we're geting it and setting it to 50MHz. What if the clock is > not what we think it is? We only set integrated_phy to 50M, which are all known targets. For external PHYs, we do not perform frequency settings. > > I'm not sure we should be delving in to some other device's DT > properties to then get resources that it _uses_ to then effectively > take control those resources. > > I think we need way more detail on what's going on. Commit da114122b83 > merely stated: > > For external phy, clk_phy should be optional, and some external phy > need the clock input from clk_phy. This patch adds support for setting > clk_phy for external phy. > > If the external PHY requires a clock supplied to it, shouldn't the PHY > driver itself be getting that clock and setting it appropriately? >