From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Shi, Yang" Subject: Re: [RFC PATCH] kernfs: create raw version kernfs_path_len and kernfs_path Date: Fri, 26 Feb 2016 12:23:17 -0800 Message-ID: <56D0B435.4080309@linaro.org> References: <1456510505-6620-1-git-send-email-yang.shi@linaro.org> <20160226135628.09ce727c@gandalf.local.home> <56D0A97E.90706@linaro.org> <56D0AEAC.3070002@linaro.org> <20160226151503.39d39e45@gandalf.local.home> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Cc: gregkh@linuxfoundation.org, tj@kernel.org, lizefan@huawei.com, tglx@linutronix.de, bigeasy@linutronix.de, linux-kernel@vger.kernel.org, linux-rt-users@vger.kernel.org, linaro-kernel@lists.linaro.org To: Steven Rostedt Return-path: Received: from mail-pf0-f179.google.com ([209.85.192.179]:34941 "EHLO mail-pf0-f179.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754003AbcBZUXT (ORCPT ); Fri, 26 Feb 2016 15:23:19 -0500 Received: by mail-pf0-f179.google.com with SMTP id w128so9723099pfb.2 for ; Fri, 26 Feb 2016 12:23:19 -0800 (PST) In-Reply-To: <20160226151503.39d39e45@gandalf.local.home> Sender: linux-rt-users-owner@vger.kernel.org List-ID: On 2/26/2016 12:15 PM, Steven Rostedt wrote: > On Fri, 26 Feb 2016 11:59:40 -0800 > "Shi, Yang" wrote: > > >> BTW, it sounds this is not the only point where kernfs_node could be >> updated, __kernfs_remove should need synchronize_sched too. >> > > Question is, can the kernfs of a cgroup be removed while the cgroup is > still active? Hmm, it sounds unlikely to me. Yang > > I don't see the kernfs_rename_lock being held anywhere in that > remove. If it can be an issue there with this patch, then it's an issue > today, because the kernfs_mutex is not held by the tracepoint. > > -- Steve >