2020-04-21 20:13:52 +00:00
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From 135e815b481b01484f140a639e2482570daa238d Mon Sep 17 00:00:00 2001
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2018-08-27 14:32:32 +00:00
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From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
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Date: Mon, 11 Apr 2016 16:55:02 +0200
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2020-04-21 20:13:52 +00:00
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Subject: [PATCH 168/325] tty: serial: 8250: don't take the trylock during oops
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Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/4.19/older/patches-4.19.115-rt48.tar.xz
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2018-08-27 14:32:32 +00:00
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An oops with irqs off (panic() from irqsafe hrtimer like the watchdog
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timer) will lead to a lockdep warning on each invocation and as such
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never completes.
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Therefore we skip the trylock in the oops case.
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Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
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---
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2019-04-08 23:49:20 +00:00
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drivers/tty/serial/8250/8250_port.c | 4 +---
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2018-08-27 14:32:32 +00:00
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1 file changed, 1 insertion(+), 3 deletions(-)
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2019-04-08 23:49:20 +00:00
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diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c
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2020-04-21 20:13:52 +00:00
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index 5a04d4ddca73..79e509468161 100644
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2018-08-27 14:32:32 +00:00
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--- a/drivers/tty/serial/8250/8250_port.c
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+++ b/drivers/tty/serial/8250/8250_port.c
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2020-04-21 20:13:52 +00:00
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@@ -3243,10 +3243,8 @@ void serial8250_console_write(struct uart_8250_port *up, const char *s,
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2018-08-27 14:32:32 +00:00
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serial8250_rpm_get(up);
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- if (port->sysrq)
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+ if (port->sysrq || oops_in_progress)
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locked = 0;
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- else if (oops_in_progress)
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- locked = spin_trylock_irqsave(&port->lock, flags);
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else
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spin_lock_irqsave(&port->lock, flags);
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2020-01-03 23:36:11 +00:00
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--
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2020-04-09 19:44:24 +00:00
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2.25.1
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2020-01-03 23:36:11 +00:00
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