From 8360063bfae53a765464aa39755b49cf736f1df0 Mon Sep 17 00:00:00 2001 From: John Ogness Date: Thu, 19 Dec 2019 12:59:22 +0106 Subject: [PATCH] printk: fix exclusive_console replaying [ Upstream commit def97da136515cb289a14729292c193e0a93bc64 ] Commit f92b070f2dc8 ("printk: Do not miss new messages when replaying the log") introduced a new variable @exclusive_console_stop_seq to store when an exclusive console should stop printing. It should be set to the @console_seq value at registration. However, @console_seq is previously set to @syslog_seq so that the exclusive console knows where to begin. This results in the exclusive console immediately reactivating all the other consoles and thus repeating the messages for those consoles. Set @console_seq after @exclusive_console_stop_seq has stored the current @console_seq value. Fixes: f92b070f2dc8 ("printk: Do not miss new messages when replaying the log") Link: http://lkml.kernel.org/r/20191219115322.31160-1-john.ogness@linutronix.de Cc: Steven Rostedt Cc: linux-kernel@vger.kernel.org Signed-off-by: John Ogness Acked-by: Sergey Senozhatsky Signed-off-by: Petr Mladek Signed-off-by: Sasha Levin --- kernel/printk/printk.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c index 845efad..7a2fdc09 100644 --- a/kernel/printk/printk.c +++ b/kernel/printk/printk.c @@ -2717,8 +2717,6 @@ void register_console(struct console *newcon) * for us. */ logbuf_lock_irqsave(flags); - console_seq = syslog_seq; - console_idx = syslog_idx; /* * We're about to replay the log buffer. Only do this to the * just-registered console to avoid excessive message spam to @@ -2730,6 +2728,8 @@ void register_console(struct console *newcon) */ exclusive_console = newcon; exclusive_console_stop_seq = console_seq; + console_seq = syslog_seq; + console_idx = syslog_idx; logbuf_unlock_irqrestore(flags); } console_unlock(); -- 2.7.4