[PATCH v1 0/3] console, serial8250: Disable PM and DMA ops

From: Andy Shevchenko
Date: Tue May 15 2018 - 14:34:35 EST


Kernel console is sensitive to any kind of complex work needed to print
out anything on it. One such case is emergency print during Oops.

This series proposes to disable runtime PM and DMA operations on 8250
serial console.

More detailed explanation why is provided in patch 2.

The series has been in our internal trees for years already with no
problems observed.

Andy Shevchenko (3):
console: introduce ->exit() callback
serial: 8250_port: Don't use power management for kernel console
serial: 8250_port: Disable DMA operations for kernel console

drivers/tty/serial/8250/8250_core.c | 9 +++++++++
drivers/tty/serial/8250/8250_port.c | 27 ++++++++++++++++++++++-----
include/linux/console.h | 1 +
include/linux/serial_8250.h | 1 +
kernel/printk/printk.c | 3 +++
5 files changed, 36 insertions(+), 5 deletions(-)

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2.17.0