From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S936730Ab3DJAbI (ORCPT ); Tue, 9 Apr 2013 20:31:08 -0400 Received: from hrndva-omtalb.mail.rr.com ([71.74.56.122]:4970 "EHLO hrndva-omtalb.mail.rr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1762821Ab3DJAbF (ORCPT ); Tue, 9 Apr 2013 20:31:05 -0400 X-Authority-Analysis: v=2.0 cv=aOZyWMBm c=1 sm=0 a=rXTBtCOcEpjy1lPqhTCpEQ==:17 a=mNMOxpOpBa8A:10 a=i53ZzN_X_rgA:10 a=5SG0PmZfjMsA:10 a=IkcTkHD0fZMA:10 a=meVymXHHAAAA:8 a=NxKs5EB5JOMA:10 a=57SyGIRnAAAA:8 a=VwQbUJbxAAAA:8 a=CjwrrDH1c_TTZ7SPd1cA:9 a=QEXdDO2ut3YA:10 a=TIV7c6GJmisA:10 a=LI9Vle30uBYA:10 a=rXTBtCOcEpjy1lPqhTCpEQ==:117 X-Cloudmark-Score: 0 X-Authenticated-User: X-Originating-IP: 74.67.115.198 Message-ID: <1365553863.25498.84.camel@gandalf.local.home> Subject: Re: [PATCH 3/3] tracing: Check cpu file on tracing_release() From: Steven Rostedt To: Namhyung Kim Cc: Frederic Weisbecker , LKML , Namhyung Kim Date: Tue, 09 Apr 2013 20:31:03 -0400 In-Reply-To: <1365553093-10180-3-git-send-email-namhyung@kernel.org> References: <1365553093-10180-1-git-send-email-namhyung@kernel.org> <1365553093-10180-3-git-send-email-namhyung@kernel.org> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.4.4-2 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 2013-04-10 at 09:18 +0900, Namhyung Kim wrote: > From: Namhyung Kim > > It looks like tracing_release() lacks checking iter->cpu_file so that > closing a per_cpu trace file would attempt to close all cpu buffers. > > Signed-off-by: Namhyung Kim > --- > kernel/trace/trace.c | 8 +++++++- > 1 file changed, 7 insertions(+), 1 deletion(-) > > diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c > index 7270460cfe3c..0beddcb80509 100644 > --- a/kernel/trace/trace.c > +++ b/kernel/trace/trace.c > @@ -2883,7 +2883,13 @@ static int tracing_release(struct inode *inode, struct file *file) > WARN_ON(!tr->ref); > tr->ref--; > > - for_each_tracing_cpu(cpu) { > + if (iter->cpu_file == RING_BUFFER_ALL_CPUS) { > + for_each_tracing_cpu(cpu) { > + if (iter->buffer_iter[cpu]) Only the cpu that is assigned gets buffer_iter[cpu] set. The other buffer_iter[cpus] will simply be ignored. -- Steve > + ring_buffer_read_finish(iter->buffer_iter[cpu]); > + } > + } else { > + cpu = iter->cpu_file; > if (iter->buffer_iter[cpu]) > ring_buffer_read_finish(iter->buffer_iter[cpu]); > }