Return-Path: Message-Id: <20130722142126.542426716@goodmis.org> Date: Mon, 22 Jul 2013 10:20:01 -0400 From: Steven Rostedt To: linux-kernel@vger.kernel.org Cc: Linus Torvalds , Ingo Molnar , Andrew Morton , Masami Hiramatsu , Oleg Nesterov , Ingo Molnar , Frederic Weisbecker , Subject: [PATCH 14/14] tracing: Kill the unbalanced tr->ref++ in tracing_buffers_open() References: <20130722141947.972915744@goodmis.org> Content-Disposition: inline; filename=0014-tracing-Kill-the-unbalanced-tr-ref-in-tracing_buffer.patch Sender: linux-kernel-owner@vger.kernel.org List-ID: From: Oleg Nesterov tracing_buffers_open() does trace_array_get() and then it wrongly inrcements tr->ref again under trace_types_lock. This means that every caller leaks trace_array: # cd /sys/kernel/debug/tracing/ # mkdir instances/X # true < instances/X/per_cpu/cpu0/trace_pipe_raw # rmdir instances/X rmdir: failed to remove `instances/X': Device or resource busy Link: http://lkml.kernel.org/r/20130719153644.GA18899@redhat.com Cc: Ingo Molnar Cc: Frederic Weisbecker Cc: Masami Hiramatsu Cc: stable@vger.kernel.org # 3.10 Signed-off-by: Oleg Nesterov Signed-off-by: Steven Rostedt --- kernel/trace/trace.c | 2 -- 1 file changed, 2 deletions(-) diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 7d9ceab..3f24777 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -4959,8 +4959,6 @@ static int tracing_buffers_open(struct inode *inode, struct file *filp) mutex_lock(&trace_types_lock); - tr->ref++; - info->iter.tr = tr; info->iter.cpu_file = tc->cpu; info->iter.trace = tr->current_trace; -- 1.7.10.4