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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,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 46BFAC2BBFD for ; Sat, 11 Apr 2020 23:36:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1EB7A20787 for ; Sat, 11 Apr 2020 23:36:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1586648176; bh=EHKM173hDAEkxmP/uNv4sY3k5Xn+LR2ptxQZRGg5XFA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=BtEtA2jRhMyt1uuYAKw+pYe5xfUwVs6JR45az3ABbk7ZfuuIiKmOk2oOZVrXWBYiU 4/0shX90B3czwWd+SoPvdfzME6FRr4IvgAvHEZ0ecXhxUjL3PhBQuzxiSyUIfW0kSL eYJak5K83RaR53APQH55XpC6yIxnnSgruseR6T6Y= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728756AbgDKXgO (ORCPT ); Sat, 11 Apr 2020 19:36:14 -0400 Received: from mail.kernel.org ([198.145.29.99]:45992 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729001AbgDKXIq (ORCPT ); Sat, 11 Apr 2020 19:08:46 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 4909021D79; Sat, 11 Apr 2020 23:08:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1586646526; bh=EHKM173hDAEkxmP/uNv4sY3k5Xn+LR2ptxQZRGg5XFA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=NMIkAP4To63Y3mEPwWIYRnczeX9CZp/92UI08feZtfSWHxhdI6Fccxqm2uFqkg8Zk ANkOh1/0noP+6KTpBlgFSLDgWhpKUTw1OrGqW/H6koJXYRiED9NA4gKhZVGUpUhSIF 4wEmBmAmuBCT0h4Ckmg5IRNM1e8ANamRMkO3fCnA= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Douglas Anderson , Greg Kroah-Hartman , Sasha Levin , linux-arm-msm@vger.kernel.org, linux-serial@vger.kernel.org Subject: [PATCH AUTOSEL 5.5 081/121] tty: serial: qcom_geni_serial: No need to stop tx/rx on UART shutdown Date: Sat, 11 Apr 2020 19:06:26 -0400 Message-Id: <20200411230706.23855-81-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200411230706.23855-1-sashal@kernel.org> References: <20200411230706.23855-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-serial-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-serial@vger.kernel.org From: Douglas Anderson [ Upstream commit e83766334f96b3396a71c7baa3b0b53dfd5190cd ] On a board using qcom_geni_serial I found that I could no longer interact with kdb if I got a crash after the "agetty" running on the same serial port was killed. This meant that various classes of crashes that happened at reboot time were undebuggable. Reading through the code, I couldn't figure out why qcom_geni_serial felt the need to run so much code at port shutdown time. All we need to do is disable the interrupt. After I make this change then a hardcoded kgdb_breakpoint in some late shutdown code now allows me to interact with the debugger. I also could freely close / re-open the port without problems. Fixes: c4f528795d1a ("tty: serial: msm_geni_serial: Add serial driver support for GENI based QUP") Signed-off-by: Douglas Anderson Link: https://lore.kernel.org/r/20200313134635.1.Icf54c533065306b02b880c46dfd401d8db34e213@changeid Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin --- drivers/tty/serial/qcom_geni_serial.c | 6 ------ 1 file changed, 6 deletions(-) diff --git a/drivers/tty/serial/qcom_geni_serial.c b/drivers/tty/serial/qcom_geni_serial.c index ebace5ad175ca..7a6fa4ab780f7 100644 --- a/drivers/tty/serial/qcom_geni_serial.c +++ b/drivers/tty/serial/qcom_geni_serial.c @@ -846,17 +846,11 @@ static void get_tx_fifo_size(struct qcom_geni_serial_port *port) static void qcom_geni_serial_shutdown(struct uart_port *uport) { - unsigned long flags; - /* Stop the console before stopping the current tx */ if (uart_console(uport)) console_stop(uport->cons); disable_irq(uport->irq); - spin_lock_irqsave(&uport->lock, flags); - qcom_geni_serial_stop_tx(uport); - qcom_geni_serial_stop_rx(uport); - spin_unlock_irqrestore(&uport->lock, flags); } static int qcom_geni_serial_port_setup(struct uart_port *uport) -- 2.20.1