From mboxrd@z Thu Jan  1 00:00:00 1970
From: Christoph Hellwig <hch@lst.de>
Subject: Re: [PATCH 01/12] target: Convert se_node_acl->device_list[] to
	RCU hlist
Date: Sun, 17 May 2015 18:51:42 +0200
Message-ID: <20150517165142.GA17217@lst.de>
References: <1431422736-29125-1-git-send-email-nab@daterainc.com> <1431422736-29125-2-git-send-email-nab@daterainc.com> <20150513063555.GA21770@lst.de> <1431506771.26897.78.camel@haakon3.risingtidesystems.com>
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To: "Nicholas A. Bellinger" <nab@linux-iscsi.org>
Cc: Christoph Hellwig <hch@lst.de>, "Nicholas A. Bellinger" <nab@daterainc.com>, target-devel <target-devel@vger.kernel.org>, linux-scsi <linux-scsi@vger.kernel.org>, linux-kernel <linux-kernel@vger.kernel.org>, Hannes Reinecke <hare@suse.de>, Sagi Grimberg <sagig@mellanox.com>
List-Id: linux-scsi@vger.kernel.org

On Wed, May 13, 2015 at 01:46:11AM -0700, Nicholas A. Bellinger wrote:
> Updated to use a mirror lun->lun_rtpi, with the assignment from sep_rtpi
> occuring in core_dev_export() code.

>>From looking at your current tree I suspect freeing the se_port structure
using kfree_rcu might be a better idea.  Together with dropping the references
to the se_device from call_rcu context this basically means all pointers
in struct se_lun are rcu protected which is much safer if you want
to access struct se_lun under rcu protection, as this avoids having to
deal with special cases.  Additionally that basically allows you to
replace lun_sep_lock with rcu_read_lock for anything remotely like
a fast path.