Re: [PATCH v4 3/6] iommu/mediatek: Add error path for loop of mm_dts_parse

From: Dan Carpenter <dan.carpenter@oracle.com>
To: Yong Wu <yong.wu@mediatek.com>
Cc: Joerg Roedel <joro@8bytes.org>,
	Matthias Brugger <matthias.bgg@gmail.com>,
	Will Deacon <will@kernel.org>,
	Robin Murphy <robin.murphy@arm.com>,
	iommu@lists.linux.dev, iommu@lists.linux-foundation.org,
	linux-mediatek@lists.infradead.org,
	linux-arm-kernel@lists.infradead.org,
	linux-kernel@vger.kernel.org,
	AngeloGioacchino Del Regno
	<angelogioacchino.delregno@collabora.com>,
	mingyuan.ma@mediatek.com, yf.wang@mediatek.com,
	libo.kang@mediatek.com, chengci.xu@mediatek.com,
	youlin.pei@mediatek.com, anan.sun@mediatek.com,
	xueqi.zhang@mediatek.com, Guenter Roeck <groeck@chromium.org>
Subject: Re: [PATCH v4 3/6] iommu/mediatek: Add error path for loop of mm_dts_parse
Date: Tue, 30 Aug 2022 11:32:07 +0300	[thread overview]
Message-ID: <20220830083206.GT2030@kadam> (raw)
In-Reply-To: <20220824064306.21495-4-yong.wu@mediatek.com>

On Wed, Aug 24, 2022 at 02:43:03PM +0800, Yong Wu wrote:
> The mtk_iommu_mm_dts_parse will parse the smi larbs nodes. if the i+1
> larb is parsed fail, we should put_device for the 0..i larbs.
> 
> There are two places need to comment:
> 1) The larbid may be not linear mapping, we should loop whole
>    the array in the error path.
> 2) I move this line position: "data->larb_imu[id].dev = &plarbdev->dev;"
>    That means set data->larb_imu[id].dev before the error path.
>    then we don't need "platform_device_put(plarbdev)" again while
>    probe_defer case. All depend on "put_device" in the error path in error
>    cases.

I don't understand what you're saying here.  There is still a
platform_device_put(plarbdev) on the success path after
component_match_add().

So if we fail when i == 2 then we do:

	put_device(data->larb_imu[2].dev);

But for the previous iterations has both platform_device_put()
and put_device() called for them.

regards,
dan carpenter