From: John Ogness john.ogness@linutronix.de
[ 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 rostedt@goodmis.org Cc: linux-kernel@vger.kernel.org Signed-off-by: John Ogness john.ogness@linutronix.de Acked-by: Sergey Senozhatsky sergey.senozhatsky@gmail.com Signed-off-by: Petr Mladek pmladek@suse.com Signed-off-by: Sasha Levin sashal@kernel.org --- 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 845efadaf7ecf..7a2fdc097c8cb 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();