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Date:   Mon, 14 May 2018 15:34:42 +0200
From:   Johannes Thumshirn <jthumshirn@suse.de>
To:     "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc:     Christoph Hellwig <hch@infradead.org>,
        Keith Busch <keith.busch@intel.com>,
        Sagi Grimberg <sagi@grimberg.me>,
        Linux Kernel Mailinglist <linux-kernel@vger.kernel.org>,
        Linux NVMe Mailinglist <linux-nvme@lists.infradead.org>,
        Hannes Reinecke <hare@suse.de>, Christoph Hellwig <hch@lst.de>
Subject: Re: [PATCH] nvme: fix lockdep warning in
 nvme_mpath_clear_current_path
Message-ID: <20180514133442.dyvveuxkaeithb4r@linux-x5ow.site>
References: <20180514121312.13624-1-jthumshirn@suse.de>
 <20180514124230.GA654@infradead.org>
 <20180514133105.GU26088@linux.vnet.ibm.com>
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On Mon, May 14, 2018 at 06:31:05AM -0700, Paul E. McKenney wrote:
> If you are just looking at the value of an RCU-protected pointer, then
> using rcu_access_pointer() will cause RCU to just read out the value
> and otherwise keeps its mouth shut.
> 
> If you use rcu_access_pointer() and later dereference the value without
> protection, you will of course get what you deserve, good and hard.  ;-)

Thanks Paul.

Christoph, I'll be sending the v2 probably tomorrow as I have more
lockdep fixes for nvme in the pipe and I'll send them out as a
complete series.

-- 
Johannes Thumshirn                                          Storage
jthumshirn@suse.de                                +49 911 74053 689
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