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Date: Fri, 15 Sep 2017 07:49:03 -0700
From: Christoph Hellwig <hch@infradead.org>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mimi Zohar <zohar@linux.vnet.ibm.com>,
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        Christoph Hellwig <hch@lst.de>
Subject: Re: [PATCH 3/3] ima: use fs method to read integrity data
Message-ID: <20170915144903.GA3854@infradead.org>
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On Thu, Sep 14, 2017 at 10:50:27PM -0700, Linus Torvalds wrote:
> This is still wrong.
> 
> (a) there is no explanation for why we need that exclusive lock in the
> first place
> 
> Why should a read need exclusive access? You'd think shared is sufficient.
> But regardless, it needs *explanation*.

Shared is sufficient, and nothing in the patch (except for the
description) actually requires an exclusive lock.  It just happens that
ima holds it exclusive for other internal reasons.