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Date:   Fri, 4 Sep 2020 19:06:17 +0100
From:   Al Viro <viro@zeniv.linux.org.uk>
To:     Christoph Hellwig <hch@lst.de>
Cc:     Paul Walmsley <paul.walmsley@sifive.com>,
        Palmer Dabbelt <palmer@dabbelt.com>,
        Arnd Bergmann <arnd@arndb.de>, linux-riscv@lists.infradead.org,
        linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org
Subject: Re: [PATCH 3/8] asm-generic: fix unaligned access hamdling in
 raw_copy_{from,to}_user
Message-ID: <20200904180617.GQ1236603@ZenIV.linux.org.uk>
References: <20200904165216.1799796-1-hch@lst.de>
 <20200904165216.1799796-4-hch@lst.de>
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On Fri, Sep 04, 2020 at 06:52:11PM +0200, Christoph Hellwig wrote:
> Use get_unaligned and put_unaligned for the small constant size cases
> in the generic uaccess routines.  This ensures they can be used for
> architectures that do not support unaligned loads and stores, while
> being a no-op for those that do.

Frankly, I would rather get rid of those constant-sized cases entirely;
sure, we'd need to adjust asm-generic/uaccess.h defaults for __get_user(),
but there that kind of stuff would make sense; in raw_copy_from_user()
it really doesn't.