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Date:   Thu, 28 May 2020 20:03:17 +0100
From:   Al Viro <viro@zeniv.linux.org.uk>
To:     Christoph Hellwig <hch@lst.de>
Cc:     Linus Torvalds <torvalds@linux-foundation.org>,
        Ian Kent <raven@themaw.net>,
        David Howells <dhowells@redhat.com>,
        linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org,
        linux-security-module@vger.kernel.org,
        netfilter-devel@vger.kernel.org
Subject: Re: [PATCH 14/14] fs: don't change the address limit for ->read_iter
 in __kernel_read
Message-ID: <20200528190317.GN23230@ZenIV.linux.org.uk>
References: <20200528054043.621510-1-hch@lst.de>
 <20200528054043.621510-15-hch@lst.de>
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On Thu, May 28, 2020 at 07:40:43AM +0200, Christoph Hellwig wrote:
> If we read to a file that implements ->read_iter there is no need
> to change the address limit if we send a kvec down.  Implement that
> case, and prefer it over using plain ->read with a changed address
> limit if available.

Ditto re never converting something that bails out on uaccess_kernel()
in ->read() over to ->read_iter().