Date:   Tue, 21 Feb 2023 19:38:09 +0800
From:   Baoquan He <bhe@redhat.com>
To:     Geert Uytterhoeven <geert@linux-m68k.org>
Cc:     linux-kernel@vger.kernel.org, linux-mm@kvack.org, arnd@arndb.de,
        hch@infradead.org, mcgrof@kernel.org
Subject: Re: [RFC PATCH 2/2] arch/*/io.h: remove ioremap_uc in some
 architectures
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References: <20230221060723.26291-1-bhe@redhat.com>
 <20230221060723.26291-3-bhe@redhat.com>
 <CAMuHMdV4efVX8X1KoLJ-3pmzsxnU6TODw3b_37ZK771rfrqi7A@mail.gmail.com>
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On 02/21/23 at 11:03am, Geert Uytterhoeven wrote:
> Hi Baoquan,
> 
> Thanks for your patch!
> 
> On Tue, Feb 21, 2023 at 7:36 AM Baoquan He <bhe@redhat.com> wrote:
> > ioremap_uc() is only meaningful on old x86-32 systems with the PAT
> > extension, and on ia64 with its slightly unconventional ioremap()
> > behavior, everywhere else this is the same as ioremap() anyway.
> >
> > So here, remove the ioremap_uc() definition in architecutures other
> > than x86 and ia64. These architectures all have asm-generic/io.h
> > included and will have the default ioremap_uc() definition which
> > returns NULL. If any ARCH really needs a specific ioremap_uc() for
> 
> Please make it very clear that this changes existing behavior.
> At first, I had completely missed that.

Sure, I will update log.

> 
> And of course the documentation should be updated to reflect that.

Makes sense, will do.

> 
> > its own usage, one ioremap_uc() can be added in the ARH.
> 
> s/ARH/ARCH/

Will update.

> 
> >  arch/m68k/include/asm/kmap.h   | 1 -
> 
> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>

Thanks for reviewing.