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Date:   Wed, 13 Oct 2021 05:41:58 -0700
From:   Luis Chamberlain <mcgrof@kernel.org>
To:     Kees Cook <keescook@chromium.org>
Cc:     tj@kernel.org, gregkh@linuxfoundation.org,
        akpm@linux-foundation.org, minchan@kernel.org, jeyu@kernel.org,
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        linux-spdx@vger.kernel.org, linux-doc@vger.kernel.org,
        linux-block@vger.kernel.org, linux-fsdevel@vger.kernel.org,
        linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v8 09/12] sysfs: fix deadlock race with module removal
Message-ID: <YWbUFnway11HwuZl@bombadil.infradead.org>
References: <20210927163805.808907-1-mcgrof@kernel.org>
 <20210927163805.808907-10-mcgrof@kernel.org>
 <202110051315.B2165F455@keescook>
 <YWS5+uyDQ4qklTcT@bombadil.infradead.org>
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On Mon, Oct 11, 2021 at 03:26:02PM -0700, Luis Chamberlain wrote:
> On Tue, Oct 05, 2021 at 01:50:31PM -0700, Kees Cook wrote:
> > For example, why does this not work?
> 
> It does for the write case for sure,

I mispoke, just for the record, the changes you mentioned actually don't
suffice for the test cases in question for test_sysfs, the deadlock
still occurs with those changes. At first I thought it did but I had failed
to remove my own fix first on fs/kernfs/dir.c. After removing that and
just trying the proposed changes I confirm it does not fix the deadlock.

  Luis