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Date:   Fri, 11 Aug 2023 01:12:38 -0700
From:   Christoph Hellwig <hch@infradead.org>
To:     Richard Weinberger <richard@nod.at>
Cc:     Christoph Hellwig <hch@infradead.org>,
        linux-mtd <linux-mtd@lists.infradead.org>,
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Subject: Re: [PATCH 1/7] ubi: block: Refactor sg list processing for highmem
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On Thu, Aug 10, 2023 at 09:54:46PM +0200, Richard Weinberger wrote:
> > But why add the bounce buffering first if you can avoid it from the
> > very beginning by just using kmap_local instead of adding a new
> > caller for the deprecate kmap_atomic?
> 
> Because I want this fix also in all stable trees. kmap_local() is rather
> new. When back porting patch 1/7, bounce buffers and kmap_atomic()
> are needed anyway.
> By doing this in patch 1/7 I avoid backport troubles and keep the
> delta between upstream and stable trees minimal.

Just use plain kmap for the historic backports.