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Date:   Wed, 19 Oct 2022 11:17:23 +0200
From:   Johan Hovold <johan@kernel.org>
To:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc:     linux-kernel@vger.kernel.org, stable@vger.kernel.org,
        Johan Hovold <johan+linaro@kernel.org>,
        Vinod Koul <vkoul@kernel.org>, Sasha Levin <sashal@kernel.org>
Subject: Re: [PATCH 6.0 524/862] phy: qcom-qmp-pcie: fix memleak on probe
 deferral
Message-ID: <Y0/Ao3M8Ob5dvEFr@hovoldconsulting.com>
References: <20221019083249.951566199@linuxfoundation.org>
 <20221019083313.126741569@linuxfoundation.org>
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On Wed, Oct 19, 2022 at 10:30:11AM +0200, Greg Kroah-Hartman wrote:
> From: Johan Hovold <johan+linaro@kernel.org>
> 
> [ Upstream commit 4be26f695ffa458b065b7942dbff9393bf0836ea ]
> 
> Switch to using the device-managed of_iomap helper to avoid leaking
> memory on probe deferral and driver unbind.
> 
> Note that this helper checks for already reserved regions and may fail
> if there are multiple devices claiming the same memory.

In case of a malformed dts, the above new check can prevent the driver
from binding. Fixing tiny memory leaks on driver unbind does not
outweigh that risk and, again, the stable tag was left out on purpose.

Please drop.

> Fixes: e78f3d15e115 ("phy: qcom-qmp: new qmp phy driver for qcom-chipsets")
> Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
> Link: https://lore.kernel.org/r/20220916102340.11520-3-johan+linaro@kernel.org
> Signed-off-by: Vinod Koul <vkoul@kernel.org>
> Signed-off-by: Sasha Levin <sashal@kernel.org>
> ---
>  drivers/phy/qualcomm/phy-qcom-qmp-pcie.c | 34 ++++++++++++------------
>  1 file changed, 17 insertions(+), 17 deletions(-)
> 
> diff --git a/drivers/phy/qualcomm/phy-qcom-qmp-pcie.c b/drivers/phy/qualcomm/phy-qcom-qmp-pcie.c
> index 0e0f2482827a..819bcd975ba4 100644
> --- a/drivers/phy/qualcomm/phy-qcom-qmp-pcie.c
> +++ b/drivers/phy/qualcomm/phy-qcom-qmp-pcie.c
> @@ -2329,17 +2329,17 @@ int qcom_qmp_phy_pcie_create(struct device *dev, struct device_node *np, int id,
>  	 * For dual lane PHYs: tx2 -> 3, rx2 -> 4, pcs_misc (optional) -> 5
>  	 * For single lane PHYs: pcs_misc (optional) -> 3.
>  	 */
> -	qphy->tx = of_iomap(np, 0);
> -	if (!qphy->tx)
> -		return -ENOMEM;
> +	qphy->tx = devm_of_iomap(dev, np, 0, NULL);
> +	if (IS_ERR(qphy->tx))
> +		return PTR_ERR(qphy->tx);
>  
> -	qphy->rx = of_iomap(np, 1);
> -	if (!qphy->rx)
> -		return -ENOMEM;
> +	qphy->rx = devm_of_iomap(dev, np, 1, NULL);
> +	if (IS_ERR(qphy->rx))
> +		return PTR_ERR(qphy->rx);
>  
> -	qphy->pcs = of_iomap(np, 2);
> -	if (!qphy->pcs)
> -		return -ENOMEM;
> +	qphy->pcs = devm_of_iomap(dev, np, 2, NULL);
> +	if (IS_ERR(qphy->pcs))
> +		return PTR_ERR(qphy->pcs);
>  
>  	/*
>  	 * If this is a dual-lane PHY, then there should be registers for the
> @@ -2348,9 +2348,9 @@ int qcom_qmp_phy_pcie_create(struct device *dev, struct device_node *np, int id,
>  	 * offset from the first lane.
>  	 */
>  	if (cfg->is_dual_lane_phy) {
> -		qphy->tx2 = of_iomap(np, 3);
> -		qphy->rx2 = of_iomap(np, 4);
> -		if (!qphy->tx2 || !qphy->rx2) {
> +		qphy->tx2 = devm_of_iomap(dev, np, 3, NULL);
> +		qphy->rx2 = devm_of_iomap(dev, np, 4, NULL);
> +		if (IS_ERR(qphy->tx2) || IS_ERR(qphy->rx2)) {
>  			dev_warn(dev,
>  				 "Underspecified device tree, falling back to legacy register regions\n");
>  
> @@ -2360,20 +2360,20 @@ int qcom_qmp_phy_pcie_create(struct device *dev, struct device_node *np, int id,
>  			qphy->rx2 = qphy->rx + QMP_PHY_LEGACY_LANE_STRIDE;
>  
>  		} else {
> -			qphy->pcs_misc = of_iomap(np, 5);
> +			qphy->pcs_misc = devm_of_iomap(dev, np, 5, NULL);
>  		}
>  
>  	} else {
> -		qphy->pcs_misc = of_iomap(np, 3);
> +		qphy->pcs_misc = devm_of_iomap(dev, np, 3, NULL);
>  	}
>  
> -	if (!qphy->pcs_misc &&
> +	if (IS_ERR(qphy->pcs_misc) &&
>  	    of_device_is_compatible(dev->of_node, "qcom,ipq6018-qmp-pcie-phy"))
>  		qphy->pcs_misc = qphy->pcs + 0x400;
>  
> -	if (!qphy->pcs_misc) {
> +	if (IS_ERR(qphy->pcs_misc)) {
>  		if (cfg->pcs_misc_tbl || cfg->pcs_misc_tbl_sec)
> -			return -EINVAL;
> +			return PTR_ERR(qphy->pcs_misc);
>  	}
>  
>  	snprintf(prop_name, sizeof(prop_name), "pipe%d", id);

Johan