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Date: Mon, 15 Jul 2013 20:16:59 +0200
From: Oleg Nesterov <oleg@redhat.com>
To: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Steven Rostedt <rostedt@goodmis.org>,
        Peter Zijlstra <a.p.zijlstra@chello.nl>,
        Frederic Weisbecker <fweisbec@gmail.com>, linux-kernel@vger.kernel.org,
        Ingo Molnar <mingo@redhat.com>,
        Arnaldo Carvalho de Melo <acme@ghostprotocols.net>,
        Andrew Morton <akpm@linux-foundation.org>, jovi.zhangwei@huawei.com,
        Jiri Olsa <jolsa@redhat.com>,
        Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Subject: Re: [RFC PATCH V2] tracing: Check f_dentry before accessing
	event_file/call in inode->i_private
Message-ID: <20130715181659.GA18505@redhat.com>
References: <20130705003223.GA4981@redhat.com> <20130709075519.2583.96462.stgit@mhiramat-M0-7522>
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On 07/09, Masami Hiramatsu wrote:
>
> To avoid this, when opening events/*/*/enable, we have to ensure
> the dentry of the file is not unlinked yet, under event_mutex
> is locked.

Probably this can work, but I am starting to think that this ref
count becomes toooooo complex....

Could you please look at the draft patch I sent in another email?

Oleg.