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Date:   Fri, 12 Apr 2019 16:55:38 +0200
From:   Christoph Hellwig <hch@lst.de>
To:     Arnd Bergmann <arnd@arndb.de>
Cc:     Christoph Hellwig <hch@lst.de>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        linux-arch <linux-arch@vger.kernel.org>, mick@ics.forth.gr,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH, RFC] byteorder: sanity check toolchain vs kernel
 endianess
Message-ID: <20190412145538.GA24473@lst.de>
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On Fri, Apr 12, 2019 at 04:53:28PM +0200, Arnd Bergmann wrote:
> On Fri, Apr 12, 2019 at 4:36 PM Christoph Hellwig <hch@lst.de> wrote:
> >
> > When removing some dead big endian checks in the RISC-V code Nick
> > suggested that we should have some generic sanity checks.  I don't think
> > we should have thos inside the RISC-V code, but maybe it might make
> > sense to have these in the generic byteorder headers.  Note that these
> > are UAPI headers and some compilers might not actually define
> > __BYTE_ORDER__, so we first check that it actually exists.
> >
> > Suggested-by: Nick Kossifidis <mick@ics.forth.gr>
> > Signed-off-by: Christoph Hellwig <hch@lst.de>
> 
> Acked-by: Arnd Bergmann <arnd@arndb.de>
> 
> Extra checking like this is good in general, but I'm not sure I see
> exactly what kind of issue one might expect to prevent with this:

I'm personally not worried at all. Just trying to respond to Nicks
review comment and make it reasonable generic if we have to have these
checks at all.  I personally would be ok without them, I just don't
want them hidden somewhere in the RISC-V code (RISC-V is always little
endian at least right now).