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=-20.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT autolearn=unavailable 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 9F3A6C433F5 for ; Mon, 20 Sep 2021 17:27:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 80A56632F4 for ; Mon, 20 Sep 2021 17:27:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1350408AbhITR2f (ORCPT ); Mon, 20 Sep 2021 13:28:35 -0400 Received: from mail.kernel.org ([198.145.29.99]:54000 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1344266AbhITR0Z (ORCPT ); Mon, 20 Sep 2021 13:26:25 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 33031611ED; Mon, 20 Sep 2021 17:02:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1632157365; bh=i87e17WOXkm0v1LGGjaD4mjMUEFLsZckqrJ/BER2TAY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=jrygSv6hv06bNEJsfW8ccEO7MFX7F5tPC0i3dmWGWI8MPAvVHTYjyNv8oEJYPZBP7 aerGZiJOFciKMbpUmIDD4FlbnLpKPEjaFUtfQ/s3LrkBAK96Gov1O3IB948sJmTm3b JWGKf5z3W53rfOaa1Ji6i1syVvbo95YCQpRNPVOQ= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Zheyu Ma , Sasha Levin Subject: [PATCH 4.14 143/217] tty: serial: jsm: hold port lock when reporting modem line changes Date: Mon, 20 Sep 2021 18:42:44 +0200 Message-Id: <20210920163929.490314107@linuxfoundation.org> X-Mailer: git-send-email 2.33.0 In-Reply-To: <20210920163924.591371269@linuxfoundation.org> References: <20210920163924.591371269@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Zheyu Ma [ Upstream commit 240e126c28df084222f0b661321e8e3ecb0d232e ] uart_handle_dcd_change() requires a port lock to be held and will emit a warning when lockdep is enabled. Held corresponding lock to fix the following warnings. [ 132.528648] WARNING: CPU: 5 PID: 11600 at drivers/tty/serial/serial_core.c:3046 uart_handle_dcd_change+0xf4/0x120 [ 132.530482] Modules linked in: [ 132.531050] CPU: 5 PID: 11600 Comm: jsm Not tainted 5.14.0-rc1-00003-g7fef2edf7cc7-dirty #31 [ 132.535268] RIP: 0010:uart_handle_dcd_change+0xf4/0x120 [ 132.557100] Call Trace: [ 132.557562] ? __free_pages+0x83/0xb0 [ 132.558213] neo_parse_modem+0x156/0x220 [ 132.558897] neo_param+0x399/0x840 [ 132.559495] jsm_tty_open+0x12f/0x2d0 [ 132.560131] uart_startup.part.18+0x153/0x340 [ 132.560888] ? lock_is_held_type+0xe9/0x140 [ 132.561660] uart_port_activate+0x7f/0xe0 [ 132.562351] ? uart_startup.part.18+0x340/0x340 [ 132.563003] tty_port_open+0x8d/0xf0 [ 132.563523] ? uart_set_options+0x1e0/0x1e0 [ 132.564125] uart_open+0x24/0x40 [ 132.564604] tty_open+0x15c/0x630 Signed-off-by: Zheyu Ma Link: https://lore.kernel.org/r/1626242003-3809-1-git-send-email-zheyuma97@gmail.com Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin --- drivers/tty/serial/jsm/jsm_neo.c | 2 ++ drivers/tty/serial/jsm/jsm_tty.c | 3 +++ 2 files changed, 5 insertions(+) diff --git a/drivers/tty/serial/jsm/jsm_neo.c b/drivers/tty/serial/jsm/jsm_neo.c index c6fdd6369534..96e01bf4599c 100644 --- a/drivers/tty/serial/jsm/jsm_neo.c +++ b/drivers/tty/serial/jsm/jsm_neo.c @@ -827,7 +827,9 @@ static void neo_parse_isr(struct jsm_board *brd, u32 port) /* Parse any modem signal changes */ jsm_dbg(INTR, &ch->ch_bd->pci_dev, "MOD_STAT: sending to parse_modem_sigs\n"); + spin_lock_irqsave(&ch->uart_port.lock, lock_flags); neo_parse_modem(ch, readb(&ch->ch_neo_uart->msr)); + spin_unlock_irqrestore(&ch->uart_port.lock, lock_flags); } } diff --git a/drivers/tty/serial/jsm/jsm_tty.c b/drivers/tty/serial/jsm/jsm_tty.c index ec7d8383900f..7c790ff6b511 100644 --- a/drivers/tty/serial/jsm/jsm_tty.c +++ b/drivers/tty/serial/jsm/jsm_tty.c @@ -195,6 +195,7 @@ static void jsm_tty_break(struct uart_port *port, int break_state) static int jsm_tty_open(struct uart_port *port) { + unsigned long lock_flags; struct jsm_board *brd; struct jsm_channel *channel = container_of(port, struct jsm_channel, uart_port); @@ -248,6 +249,7 @@ static int jsm_tty_open(struct uart_port *port) channel->ch_cached_lsr = 0; channel->ch_stops_sent = 0; + spin_lock_irqsave(&port->lock, lock_flags); termios = &port->state->port.tty->termios; channel->ch_c_cflag = termios->c_cflag; channel->ch_c_iflag = termios->c_iflag; @@ -267,6 +269,7 @@ static int jsm_tty_open(struct uart_port *port) jsm_carrier(channel); channel->ch_open_count++; + spin_unlock_irqrestore(&port->lock, lock_flags); jsm_dbg(OPEN, &channel->ch_bd->pci_dev, "finish\n"); return 0; -- 2.30.2