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Date:   Tue, 15 Jun 2021 07:53:20 +0100
From:   Christoph Hellwig <hch@infradead.org>
To:     Christophe Leroy <christophe.leroy@csgroup.eu>
Cc:     Benjamin Herrenschmidt <benh@kernel.crashing.org>,
        Paul Mackerras <paulus@samba.org>,
        Michael Ellerman <mpe@ellerman.id.au>,
        linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 6/7] powerpc/uaccess: Add unsafe_clear_user()
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On Tue, Jun 15, 2021 at 06:41:02AM +0000, Christophe Leroy wrote:
> Implement unsafe_clear_user() for powerpc.
> It's a copy/paste of unsafe_copy_to_user() with value 0 as source.
> 
> It may be improved in a later patch by using 'dcbz' instruction
> to zeroize full cache lines at once.

Please add this to common code insted of making it powerpc specific.