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Message-ID: <2014678ca837f6aaa4cf23b4ea51e4805146c36d.camel@ozlabs.org>
Subject: Re: [RFC PATCH] powerpc/spufs: fix copy_to_user while atomic
From:   Jeremy Kerr <jk@ozlabs.org>
To:     Christoph Hellwig <hch@lst.de>
Cc:     Linus Torvalds <torvalds@linux-foundation.org>,
        Arnd Bergmann <arnd@arndb.de>,
        "Eric W . Biederman" <ebiederm@xmission.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Alexander Viro <viro@zeniv.linux.org.uk>,
        Michael Ellerman <mpe@ellerman.id.au>,
        linuxppc-dev@lists.ozlabs.org, linux-fsdevel@vger.kernel.org,
        linux-kernel@vger.kernel.org
Date:   Wed, 29 Apr 2020 14:33:13 +0800
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Hi Christoph,

> And another one that should go on top of this one to address Al's other
> compaint:

Yeah, I was pondering that one. The access_ok() is kinda redundant, but
it does avoid forcing a SPU context save on those errors.

However, it's not like we really need to optimise for the case of
invalid addresses from userspace. So, I'll include this change in the
submission to Michael's tree. Arnd - let me know if you have any
objections.

Cheers,


Jeremy