From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755201AbcLXOKZ (ORCPT ); Sat, 24 Dec 2016 09:10:25 -0500 Received: from mail-pf0-f196.google.com ([209.85.192.196]:34126 "EHLO mail-pf0-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754304AbcLXOKW (ORCPT ); Sat, 24 Dec 2016 09:10:22 -0500 From: Sergey Senozhatsky To: Andrew Morton Cc: Petr Mladek , Steven Rostedt , Peter Hurley , linux-kernel@vger.kernel.org, Sergey Senozhatsky , Sergey Senozhatsky Subject: [PATCH 2/2] printk: always report lost messages on serial console Date: Sat, 24 Dec 2016 23:09:02 +0900 Message-Id: <20161224140902.1962-3-sergey.senozhatsky@gmail.com> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20161224140902.1962-1-sergey.senozhatsky@gmail.com> References: <20161224140902.1962-1-sergey.senozhatsky@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The "printk messages dropped" report is 'attached' to a kernel message located at console_idx offset. This does not work well if we skip that message due to loglevel filtering, because in this case we also skip/lose dropped message report. Disable suppress_message_printing() loglevel filtering if we must report "printk messages dropped" condition. Signed-off-by: Sergey Senozhatsky --- kernel/printk/printk.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c index 11a9842a2f47..6a7ebcb0bb6e 100644 --- a/kernel/printk/printk.c +++ b/kernel/printk/printk.c @@ -2218,6 +2218,7 @@ void console_unlock(void) struct printk_log *msg; size_t ext_len = 0; size_t len; + bool report_dropped_msg = false; raw_spin_lock_irqsave(&logbuf_lock, flags); if (seen_seq != log_next_seq) { @@ -2232,6 +2233,7 @@ void console_unlock(void) /* messages are gone, move to first one */ console_seq = log_first_seq; console_idx = log_first_idx; + report_dropped_msg = true; } else { len = 0; } @@ -2240,7 +2242,8 @@ void console_unlock(void) break; msg = log_from_idx(console_idx); - if (suppress_message_printing(msg->level)) { + if (!report_dropped_msg && + suppress_message_printing(msg->level)) { /* * Skip record we have buffered and already printed * directly to the console when we received it, and -- 2.11.0