Jetpack/kernel/kernel-4.9/rt-patches/0192-tty-serial-8250-don-t-...

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1.1 KiB
Diff

From 93178a03d9c1a62b78d172a1811eebc369c26393 Mon Sep 17 00:00:00 2001
From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date: Mon, 11 Apr 2016 16:55:02 +0200
Subject: [PATCH 192/352] tty: serial: 8250: don't take the trylock during oops
An oops with irqs off (panic() from irqsafe hrtimer like the watchdog
timer) will lead to a lockdep warning on each invocation and as such
never completes.
Therefore we skip the trylock in the oops case.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
---
drivers/tty/serial/8250/8250_port.c | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)
diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c
index 5b54439..8205240 100644
--- a/drivers/tty/serial/8250/8250_port.c
+++ b/drivers/tty/serial/8250/8250_port.c
@@ -3143,10 +3143,8 @@ void serial8250_console_write(struct uart_8250_port *up, const char *s,
serial8250_rpm_get(up);
- if (port->sysrq)
+ if (port->sysrq || oops_in_progress)
locked = 0;
- else if (oops_in_progress)
- locked = spin_trylock_irqsave(&port->lock, flags);
else
spin_lock_irqsave(&port->lock, flags);
--
2.7.4