Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Date:   Tue, 28 Apr 2020 15:52:45 +0200
From:   Christoph Hellwig <hch@lst.de>
To:     Michael Ellerman <mpe@ellerman.id.au>
Cc:     linuxppc-dev@ozlabs.org, hch@lst.de, jk@ozlabs.org,
        viro@zeniv.linux.org.uk, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] powerpc/spufs: Add rcu_read_lock() around fcheck()
Message-ID: <20200428135245.GA2827@lst.de>
References: <20200428114811.68436-1-mpe@ellerman.id.au>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20200428114811.68436-1-mpe@ellerman.id.au>
User-Agent: Mutt/1.5.17 (2007-11-01)
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

On Tue, Apr 28, 2020 at 09:48:11PM +1000, Michael Ellerman wrote:
> 
> This comes from fcheck_files() via fcheck().
> 
> It's pretty clearly documented that fcheck() must be wrapped with
> rcu_read_lock(), so fix it.

But for this to actually be useful you'd need the rcu read lock until
your are done with the file (or got a reference).