From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id BD6A0C43219 for ; Fri, 26 Apr 2019 15:54:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 91321208CB for ; Fri, 26 Apr 2019 15:54:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726362AbfDZPyA (ORCPT ); Fri, 26 Apr 2019 11:54:00 -0400 Received: from mail.kernel.org ([198.145.29.99]:51786 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726176AbfDZPyA (ORCPT ); Fri, 26 Apr 2019 11:54:00 -0400 Received: from gandalf.local.home (cpe-66-24-58-225.stny.res.rr.com [66.24.58.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 01C902077B; Fri, 26 Apr 2019 15:53:58 +0000 (UTC) Date: Fri, 26 Apr 2019 11:53:57 -0400 From: Steven Rostedt To: Linus Torvalds Cc: LKML , Ingo Molnar , Andrew Morton Subject: [GIT PULL] tracing: Minor fixes Message-ID: <20190426115357.3ef86b4a@gandalf.local.home> X-Mailer: Claws Mail 3.17.3 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Linus, There tracing fixes: - Use "nosteal" for ring buffer splice pages - Memory leak fix in error path of trace_pid_write() - Fix preempt_enable_no_resched() (use preempt_enable()) in ring buffer code Please pull the latest trace-v5.1-rc6 tree, which can be found at: git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace.git trace-v5.1-rc6 Tag SHA1: 18d3b6ef227e69c4620f9ac687bd5200ce5169bc Head SHA1: d6097c9e4454adf1f8f2c9547c2fa6060d55d952 Jann Horn (1): tracing: Fix buffer_ref pipe ops Peter Zijlstra (1): trace: Fix preempt_enable_no_resched() abuse Wenwen Wang (1): tracing: Fix a memory leak by early error exit in trace_pid_write() ---- fs/splice.c | 4 ++-- include/linux/pipe_fs_i.h | 1 + kernel/trace/ring_buffer.c | 2 +- kernel/trace/trace.c | 33 ++++++++++++++++++--------------- 4 files changed, 22 insertions(+), 18 deletions(-) --------------------------- diff --git a/fs/splice.c b/fs/splice.c index 3ee7e82df48f..e75807380caa 100644 --- a/fs/splice.c +++ b/fs/splice.c @@ -330,8 +330,8 @@ const struct pipe_buf_operations default_pipe_buf_ops = { .get = generic_pipe_buf_get, }; -static int generic_pipe_buf_nosteal(struct pipe_inode_info *pipe, - struct pipe_buffer *buf) +int generic_pipe_buf_nosteal(struct pipe_inode_info *pipe, + struct pipe_buffer *buf) { return 1; } diff --git a/include/linux/pipe_fs_i.h b/include/linux/pipe_fs_i.h index 787d224ff43e..a830e9a00eb9 100644 --- a/include/linux/pipe_fs_i.h +++ b/include/linux/pipe_fs_i.h @@ -174,6 +174,7 @@ void free_pipe_info(struct pipe_inode_info *); void generic_pipe_buf_get(struct pipe_inode_info *, struct pipe_buffer *); int generic_pipe_buf_confirm(struct pipe_inode_info *, struct pipe_buffer *); int generic_pipe_buf_steal(struct pipe_inode_info *, struct pipe_buffer *); +int generic_pipe_buf_nosteal(struct pipe_inode_info *, struct pipe_buffer *); void generic_pipe_buf_release(struct pipe_inode_info *, struct pipe_buffer *); void pipe_buf_mark_unmergeable(struct pipe_buffer *buf); diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c index 41b6f96e5366..4ee8d8aa3d0f 100644 --- a/kernel/trace/ring_buffer.c +++ b/kernel/trace/ring_buffer.c @@ -762,7 +762,7 @@ u64 ring_buffer_time_stamp(struct ring_buffer *buffer, int cpu) preempt_disable_notrace(); time = rb_time_stamp(buffer); - preempt_enable_no_resched_notrace(); + preempt_enable_notrace(); return time; } diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 21153e64bf1c..46f68fad6373 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -496,8 +496,10 @@ int trace_pid_write(struct trace_pid_list *filtered_pids, * not modified. */ pid_list = kmalloc(sizeof(*pid_list), GFP_KERNEL); - if (!pid_list) + if (!pid_list) { + trace_parser_put(&parser); return -ENOMEM; + } pid_list->pid_max = READ_ONCE(pid_max); @@ -507,6 +509,7 @@ int trace_pid_write(struct trace_pid_list *filtered_pids, pid_list->pids = vzalloc((pid_list->pid_max + 7) >> 3); if (!pid_list->pids) { + trace_parser_put(&parser); kfree(pid_list); return -ENOMEM; } @@ -7025,19 +7028,23 @@ struct buffer_ref { struct ring_buffer *buffer; void *page; int cpu; - int ref; + refcount_t refcount; }; +static void buffer_ref_release(struct buffer_ref *ref) +{ + if (!refcount_dec_and_test(&ref->refcount)) + return; + ring_buffer_free_read_page(ref->buffer, ref->cpu, ref->page); + kfree(ref); +} + static void buffer_pipe_buf_release(struct pipe_inode_info *pipe, struct pipe_buffer *buf) { struct buffer_ref *ref = (struct buffer_ref *)buf->private; - if (--ref->ref) - return; - - ring_buffer_free_read_page(ref->buffer, ref->cpu, ref->page); - kfree(ref); + buffer_ref_release(ref); buf->private = 0; } @@ -7046,14 +7053,14 @@ static void buffer_pipe_buf_get(struct pipe_inode_info *pipe, { struct buffer_ref *ref = (struct buffer_ref *)buf->private; - ref->ref++; + refcount_inc(&ref->refcount); } /* Pipe buffer operations for a buffer. */ static const struct pipe_buf_operations buffer_pipe_buf_ops = { .confirm = generic_pipe_buf_confirm, .release = buffer_pipe_buf_release, - .steal = generic_pipe_buf_steal, + .steal = generic_pipe_buf_nosteal, .get = buffer_pipe_buf_get, }; @@ -7066,11 +7073,7 @@ static void buffer_spd_release(struct splice_pipe_desc *spd, unsigned int i) struct buffer_ref *ref = (struct buffer_ref *)spd->partial[i].private; - if (--ref->ref) - return; - - ring_buffer_free_read_page(ref->buffer, ref->cpu, ref->page); - kfree(ref); + buffer_ref_release(ref); spd->partial[i].private = 0; } @@ -7125,7 +7128,7 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos, break; } - ref->ref = 1; + refcount_set(&ref->refcount, 1); ref->buffer = iter->trace_buffer->buffer; ref->page = ring_buffer_alloc_read_page(ref->buffer, iter->cpu_file); if (IS_ERR(ref->page)) {