Date: Mon, 18 Mar 2013 17:04:11 -0700
From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: =?iso-8859-1?Q?J=F6rn?= Engel <joern@logfs.org>
Cc: "Nicholas A. Bellinger" <nab@linux-iscsi.org>,
        linux-kernel@vger.kernel.org,
        target-devel <target-devel@vger.kernel.org>
Subject: Re: [PATCH] target: close target_put_sess_cmd() vs.
 core_tmr_abort_task() race
Message-ID: <20130319000411.GA6406@kroah.com>
References: <20130318222853.GA9358@logfs.org>
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On Mon, Mar 18, 2013 at 06:28:53PM -0400, J?rn Engel wrote:
> It is possible for one thread to to take se_sess->sess_cmd_lock in
> core_tmr_abort_task() before taking a reference count on
> se_cmd->cmd_kref, while another thread in target_put_sess_cmd() drops
> se_cmd->cmd_kref before taking se_sess->sess_cmd_lock.
> 
> This introduces kref_put_and_lock() and uses it in
> target_put_sess_cmd() to close the race window.

We already have kref_put_mutex(), why not just call this
kref_put_spinlock()?

thanks,

greg k-h
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