From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753013AbeEOSeR (ORCPT ); Tue, 15 May 2018 14:34:17 -0400 Received: from mga04.intel.com ([192.55.52.120]:51327 "EHLO mga04.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752178AbeEOSeO (ORCPT ); Tue, 15 May 2018 14:34:14 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.49,404,1520924400"; d="scan'208";a="54606438" From: Andy Shevchenko To: Petr Mladek , Sergey Senozhatsky , Steven Rostedt , linux-kernel@vger.kernel.org, Greg Kroah-Hartman , Jiri Slaby , linux-serial@vger.kernel.org, Sebastian Andrzej Siewior , Arnd Bergmann Cc: Andy Shevchenko Subject: [PATCH v1 0/3] console, serial8250: Disable PM and DMA ops Date: Tue, 15 May 2018 21:34:06 +0300 Message-Id: <20180515183409.78046-1-andriy.shevchenko@linux.intel.com> X-Mailer: git-send-email 2.17.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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(-) -- 2.17.0