From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8DE8DC31E50 for ; Sun, 16 Jun 2019 14:57:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 620332070B for ; Sun, 16 Jun 2019 14:57:35 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="nyZwnWZa" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727270AbfFPO52 (ORCPT ); Sun, 16 Jun 2019 10:57:28 -0400 Received: from mail-wr1-f67.google.com ([209.85.221.67]:42393 "EHLO mail-wr1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725879AbfFPO51 (ORCPT ); Sun, 16 Jun 2019 10:57:27 -0400 Received: by mail-wr1-f67.google.com with SMTP id x17so7169008wrl.9; Sun, 16 Jun 2019 07:57:26 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id; bh=EohE1hArQHwKn6jzGJF5c0OKmDVC8mwcJ3LIed3WVcI=; b=nyZwnWZaNpCC2pexx/gFVBxgIGATsb9VbOYWhg2mNFp1efqOmmSVCpwk/ngFTmznjy QVFnpapAOZ8zbrxl3MF7qsEWTFWu3iDsxksgxgWW33YuQ4FMVWEPySM41tN/cQmRIKEc INVaDeZUXsBy5xaEnYaeL9V/wZhJLE1w7xcXgX1BDGkMPVCFcF3cemgrideSs+BSHdxw E3ZXo6vb5mXYmIdGatMZhHnIOR2Kw3Vj+9kpjyYcbJcl28c0pItuXYAjXuTFy81bxQma 6Bp1Wwobxu3J5p9+knANrmBez8BBvihYHovpBqsyNw1frUmE1Bwq3FXagjnUTbm4WrXw a+2A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=EohE1hArQHwKn6jzGJF5c0OKmDVC8mwcJ3LIed3WVcI=; b=QkV7S7WxKse++wH4Y397tBfWql0mbArTnUhK8Zs6/7u2w04jStCVgYsusChXMQ7M93 FYjcg1j/qyVr0g+JnqggvVpqSTJAwMJcOJ09fh9CoY7OaX4RzGxbolOKM9UUga7iiSES FxoGGMLiVLbMqK9Pyvizyo+/p9Zlgks8JRcivcECc3lZNNFHduHuFTXTLlOPohANw2uM d5/xGTL2S4+QDiMeRW6ATzHS7LK3HBgrUwMxeaO91niQM/8MPUJGC+7zS99MXVMzBosG 761t9rShXMmZiJVe1K2a1TXKwR/E6HQ9W/5dFsose834Ho2NsUb4eIu4Irhc4GwcpnBi r3hA== X-Gm-Message-State: APjAAAUH6jZyrz7TEYUwUUGQ2fya8Z6+YA6pFGTV8dUmI5B21C7a/9y1 6DvwsOy9wbV+Jjvk6y3SrFa0N76H X-Google-Smtp-Source: APXvYqxHAiO15++mRi+sScOtC6aCoSxoZ7DA9BTOQwHimatfszDLMcPugFD+aXscZG8uws49cmzTiA== X-Received: by 2002:a5d:4841:: with SMTP id n1mr14709466wrs.320.1560697045512; Sun, 16 Jun 2019 07:57:25 -0700 (PDT) Received: from sahara-mac.darkmatter.uae ([92.96.147.131]) by smtp.gmail.com with ESMTPSA id l19sm6203302wmj.33.2019.06.16.07.57.23 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Sun, 16 Jun 2019 07:57:25 -0700 (PDT) From: kpark3469@gmail.com To: gregkh@linuxfoundation.org Cc: jslaby@suse.com, linux-serial@vger.kernel.org, linux-kernel@vger.kernel.org, keun-o.park@darkmatter.ae Subject: [PATCH] tty: serial_core: recover uport->cons->cflag on uart_close Date: Sun, 16 Jun 2019 18:57:14 +0400 Message-Id: <1560697034-4807-1-git-send-email-kpark3469@gmail.com> X-Mailer: git-send-email 2.7.4 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Sahara Since uart_close was converted to use tty_port_close, uart_shutdown also moved to uart_tty_port_shutdown, which means it does not backup tty's termios to uart_port.console.cflag when console is closed and uart_console is true. By losing this value, serial console was not set correctly especially after suspend/resume when there is no consumer of console device. This problem resets console driver's configuration to an unwanted value and may give a performance regression in the system eventually. This patch fixes the bug introduced from v4.9 kernel. Fixes: 761ed4a94582 ("tty: serial_core: convert uart_close to use tty_port_close") Reported-by: Jouni Linnamaa Signed-off-by: Sahara --- drivers/tty/serial/serial_core.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c index 83f4dd0bfd74..a52afceb2f4e 100644 --- a/drivers/tty/serial/serial_core.c +++ b/drivers/tty/serial/serial_core.c @@ -1533,6 +1533,7 @@ static void uart_set_termios(struct tty_struct *tty, static void uart_close(struct tty_struct *tty, struct file *filp) { struct uart_state *state = tty->driver_data; + struct uart_port *uport = uart_port_check(state); if (!state) { struct uart_driver *drv = tty->driver->driver_state; @@ -1548,6 +1549,8 @@ static void uart_close(struct tty_struct *tty, struct file *filp) pr_debug("uart_close(%d) called\n", tty->index); + if (uport && uart_console(uport)) + uport->cons->cflag = tty->termios.c_cflag; tty_port_close(tty->port, tty, filp); } -- 2.17.1