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=-6.0 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,T_DKIMWL_WL_HIGH,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 40520C468BD for ; Fri, 7 Jun 2019 15:50:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1841E2146E for ; Fri, 7 Jun 2019 15:50:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1559922603; bh=uFB6JgiF588xHj90IodenLeJ8LV6T1SfOBcDmZFDST4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=blQggpjnE5nU5AAwdu6WY+kQrNeuy43EuPH6CeRW1/9J5Zs5zyMaI78HhyLmioVhU WoIz8qUe1nqA596sq1s+0tnjbink7qxhbdDjOBV8uUnmRb0mCeYLQnogQkXl/XAidD 6oDLDeeAEf5jaXtjvEEUjHNwzTrlSoFoBQdJvxE0= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731398AbfFGPuC (ORCPT ); Fri, 7 Jun 2019 11:50:02 -0400 Received: from mail.kernel.org ([198.145.29.99]:36440 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731220AbfFGPuB (ORCPT ); Fri, 7 Jun 2019 11:50:01 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id BEA3820840; Fri, 7 Jun 2019 15:50:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1559922601; bh=uFB6JgiF588xHj90IodenLeJ8LV6T1SfOBcDmZFDST4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=rogIY3N3KjbRbR1UqRnhERzd2BBErjPzdVk1p1HnWq1x91iuJ3okE+Z6OzTWkr0G9 xyGoToj0H3U335OPrQG51QMYSNglnZ1bpO/Ztqh3woJUCUgyYiGxIHXSdjlFxrffWQ ty2bn2DeEAqv8XsJtV+UxVtajqw7oGPx9yei+jNo= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Michael Rodin , Eugeniu Rosca , Simon Horman , Wolfram Sang , Geert Uytterhoeven , "George G. Davis" Subject: [PATCH 5.1 64/85] serial: sh-sci: disable DMA for uart_console Date: Fri, 7 Jun 2019 17:39:49 +0200 Message-Id: <20190607153856.427807497@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190607153849.101321647@linuxfoundation.org> References: <20190607153849.101321647@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: George G. Davis commit 099506cbbc79c0bd52b19cb6b930f256dabc3950 upstream. As noted in commit 84b40e3b57ee ("serial: 8250: omap: Disable DMA for console UART"), UART console lines use low-level PIO only access functions which will conflict with use of the line when DMA is enabled, e.g. when the console line is also used for systemd messages. So disable DMA support for UART console lines. Reported-by: Michael Rodin Link: https://patchwork.kernel.org/patch/10929511/ Tested-by: Eugeniu Rosca Reviewed-by: Simon Horman Reviewed-by: Wolfram Sang Reviewed-by: Geert Uytterhoeven Cc: stable@vger.kernel.org Signed-off-by: George G. Davis Signed-off-by: Greg Kroah-Hartman Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/sh-sci.c | 7 +++++++ 1 file changed, 7 insertions(+) --- a/drivers/tty/serial/sh-sci.c +++ b/drivers/tty/serial/sh-sci.c @@ -1557,6 +1557,13 @@ static void sci_request_dma(struct uart_ dev_dbg(port->dev, "%s: port %d\n", __func__, port->line); + /* + * DMA on console may interfere with Kernel log messages which use + * plain putchar(). So, simply don't use it with a console. + */ + if (uart_console(port)) + return; + if (!port->dev->of_node) return;