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=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT 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 85E1BC4CEC4 for ; Wed, 18 Sep 2019 13:32:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5F36921924 for ; Wed, 18 Sep 2019 13:32:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730468AbfIRNc1 (ORCPT ); Wed, 18 Sep 2019 09:32:27 -0400 Received: from mail1.windriver.com ([147.11.146.13]:52535 "EHLO mail1.windriver.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726671AbfIRNc1 (ORCPT ); Wed, 18 Sep 2019 09:32:27 -0400 Received: from ALA-HCA.corp.ad.wrs.com ([147.11.189.40]) by mail1.windriver.com (8.15.2/8.15.1) with ESMTPS id x8IDVjS5021368 (version=TLSv1 cipher=AES128-SHA bits=128 verify=FAIL); Wed, 18 Sep 2019 06:31:47 -0700 (PDT) Received: from pek-lpg-core2.corp.ad.wrs.com (128.224.153.41) by ALA-HCA.corp.ad.wrs.com (147.11.189.40) with Microsoft SMTP Server id 14.3.468.0; Wed, 18 Sep 2019 06:31:44 -0700 From: To: , , , , Subject: [PATCH] printk: Fix unnecessary returning broken pipe error from devkmsg_read Date: Wed, 18 Sep 2019 21:31:43 +0800 Message-ID: <1568813503-420025-1-git-send-email-zhe.he@windriver.com> X-Mailer: git-send-email 2.7.4 MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: He Zhe When users read the buffer from start, there is no need to return -EPIPE since the possible overflows will not affect the output. Signed-off-by: He Zhe --- kernel/printk/printk.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c index 1888f6a..4a6a129 100644 --- a/kernel/printk/printk.c +++ b/kernel/printk/printk.c @@ -886,7 +886,9 @@ static ssize_t devkmsg_read(struct file *file, char __user *buf, logbuf_lock_irq(); } - if (user->seq < log_first_seq) { + if (user->seq == 0) { + user->seq = log_first_seq; + } else if (user->seq < log_first_seq) { /* our last seen message is gone, return error and reset */ user->idx = log_first_idx; user->seq = log_first_seq; -- 2.7.4