Re: [PATCH net] net: stmmac: dwmac-rk: Ensure clk_phy doesn't contain invalid address

From: "Russell King (Oracle)" <linux@armlinux.org.uk>
To: Simon Horman <horms@kernel.org>
Cc: Yao Zi <ziyao@disroot.org>, Andrew Lunn <andrew+netdev@lunn.ch>,
	"David S. Miller" <davem@davemloft.net>,
	Eric Dumazet <edumazet@google.com>,
	Jakub Kicinski <kuba@kernel.org>, Paolo Abeni <pabeni@redhat.com>,
	Jonas Karlman <jonas@kwiboo.se>,
	David Wu <david.wu@rock-chips.com>,
	Chaoyi Chen <chaoyi.chen@rock-chips.com>,
	netdev@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
	linux-kernel@vger.kernel.org, linux-rockchip@lists.infradead.org
Subject: Re: [PATCH net] net: stmmac: dwmac-rk: Ensure clk_phy doesn't contain invalid address
Date: Thu, 4 Sep 2025 11:49:33 +0100	[thread overview]
Message-ID: <aLluvYQ-i-Z9vyp7@shell.armlinux.org.uk> (raw)
In-Reply-To: <20250904103443.GH372207@horms.kernel.org>

On Thu, Sep 04, 2025 at 11:34:43AM +0100, Simon Horman wrote:
> Thanks, and sorry for my early confusion about applying this patch.
> 
> I agree that the bug you point out is addressed by this patch.
> Although I wonder if it is cleaner not to set bsp_priv->clk_phy
> unless there is no error, rather than setting it then resetting
> it if there is an error.

+1 !

> More importantly, I wonder if there is another bug: does clk_set_rate need
> to be called in the case where there is no error and bsp_priv->integrated_phy
> is false?

I think there's another issue:

static int rk_gmac_clk_init(struct plat_stmmacenet_data *plat)
{
...
        if (plat->phy_node) {
                bsp_priv->clk_phy = of_clk_get(plat->phy_node, 0);
...

static void rk_gmac_remove(struct platform_device *pdev)
{
...
        if (priv->plat->phy_node && bsp_priv->integrated_phy)
                clk_put(bsp_priv->clk_phy);

So if bsp_priv->integrated_phy is false, then we get the clock but
don't put it.

-- 
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