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From: "Joakim  Zhang" <joakim.zhang@cixtech.com>
To: Christoph Hellwig <hch@lst.de>
CC: "m.szyprowski@samsung.com" <m.szyprowski@samsung.com>,
	"robin.murphy@arm.com" <robin.murphy@arm.com>, "iommu@lists.linux.dev"
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	<linux-kernel@vger.kernel.org>, cix-kernel-upstream
	<cix-kernel-upstream@cixtech.com>
Subject: RE: [PATCH V2] dma-mapping: Set dma_mem pointer as NULL after it's
 freed
Thread-Topic: [PATCH V2] dma-mapping: Set dma_mem pointer as NULL after it's
 freed
Thread-Index: AQHaLmcky1/MaAD/QUerCOizXimNM7CqN/MAgAAuTiA=
Date: Fri, 15 Dec 2023 14:24:48 +0000
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References: <20231214082526.1212264-1-joakim.zhang@cixtech.com>
 <20231215113226.GC6479@lst.de>
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Hi Christoph Hellwig,

> -----Original Message-----
> From: Christoph Hellwig <hch@lst.de>
> Sent: Friday, December 15, 2023 7:32 PM
> To: Joakim Zhang <joakim.zhang@cixtech.com>
> Cc: hch@lst.de; m.szyprowski@samsung.com; robin.murphy@arm.com;
> iommu@lists.linux.dev; linux-kernel@vger.kernel.org; cix-kernel-upstream
> <cix-kernel-upstream@cixtech.com>
> Subject: Re: [PATCH V2] dma-mapping: Set dma_mem pointer as NULL after
> it's freed
>=20
> I've applied this after fixing the whitespace errors.
>=20
> But we really need to get remoteporc off messing with the reserved region=
s
> itself and retire this API entirely.

Indeed, I met this issue when debugging remoteproc, this API maybe useful s=
ince some system would not support device tree, but still want to reserve m=
emory in the driver.