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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Subject: [PATCH] tty: serial: 8250: don't take the trylock during oops
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2019-02-27 18:51:46 +00:00
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Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/4.19/older/patches-4.19.25-rt16.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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drivers/tty/serial/8250/8250_port.c | 4 +---
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1 file changed, 1 insertion(+), 3 deletions(-)
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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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2018-10-30 12:40:05 +00:00
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@@ -3239,10 +3239,8 @@ void serial8250_console_write(struct uar
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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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