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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A057FC43334 for ; Wed, 15 Jun 2022 09:08:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1346459AbiFOJIF (ORCPT ); Wed, 15 Jun 2022 05:08:05 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46090 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S244794AbiFOJHt (ORCPT ); Wed, 15 Jun 2022 05:07:49 -0400 Received: from mga11.intel.com (mga11.intel.com [192.55.52.93]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id ED7FAD74; Wed, 15 Jun 2022 02:07:28 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1655284048; x=1686820048; h=from:to:subject:date:message-id:in-reply-to:references: mime-version:content-transfer-encoding; bh=tzOwzKU2PlO38M7mQ6u8ns1x2zwrHZwHhpoGZ0wAtXA=; b=juTQtbuDBce6o8s2gH1DfQL2QQ9a+RCKZZFTEzTempFAOZ48t0T4WOJy ZzFFtx9i1zEOONTqWbAcXMLExba4zS2kj6MZyJVvVHzfmfDVwBk5yxEpx k8cdgygRvOXYJZxVqweDvnrSQfVHpurVFGrh6KfxTsUZLtqqqWOWyqydg Z6CxtwBjykvYWhpL2+9WmT2Y+tXLdic7UoaFfUqSPscBI0J2Az1ex1IOx Jb4LUZJpc1RdpB+vtc/7xNMiHjpFbeN89wDuFP3iCsYPYr7rQRPBoUGnM nXzxiElM/Fn/Zr1p9N/ZFax1pbe6f8IT4d84njy1puaroYYJrhKCK+Z0E A==; X-IronPort-AV: E=McAfee;i="6400,9594,10378"; a="276464703" X-IronPort-AV: E=Sophos;i="5.91,300,1647327600"; d="scan'208";a="276464703" Received: from fmsmga006.fm.intel.com ([10.253.24.20]) by fmsmga102.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 15 Jun 2022 02:07:28 -0700 X-IronPort-AV: E=Sophos;i="5.91,300,1647327600"; d="scan'208";a="830934158" Received: from mgrymel-mobl1.ger.corp.intel.com (HELO ijarvine-MOBL2.ger.corp.intel.com) ([10.249.41.34]) by fmsmga006-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 15 Jun 2022 02:07:26 -0700 From: =?UTF-8?q?Ilpo=20J=C3=A4rvinen?= To: linux-serial@vger.kernel.org, Greg KH , Jiri Slaby , Andy Shevchenko , =?UTF-8?q?Ilpo=20J=C3=A4rvinen?= , linux-kernel@vger.kernel.org Subject: [PATCH 2/3] serial: 8250_dw: Take port lock while accessing LSR Date: Wed, 15 Jun 2022 12:06:50 +0300 Message-Id: <20220615090651.15340-3-ilpo.jarvinen@linux.intel.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20220615090651.15340-1-ilpo.jarvinen@linux.intel.com> References: <20220615090651.15340-1-ilpo.jarvinen@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-serial@vger.kernel.org Accessing LSR requires port lock because it mutates lsr_saved_flags in serial_lsr_in(). Fixes: 197eb5c416ff ("serial: 8250_dw: Use serial_lsr_in() in dw8250_handle_irq()") Signed-off-by: Ilpo Järvinen --- drivers/tty/serial/8250/8250_dw.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/tty/serial/8250/8250_dw.c b/drivers/tty/serial/8250/8250_dw.c index 4cc69bb612ab..f67fad3233e9 100644 --- a/drivers/tty/serial/8250/8250_dw.c +++ b/drivers/tty/serial/8250/8250_dw.c @@ -266,7 +266,10 @@ static int dw8250_handle_irq(struct uart_port *p) /* Manually stop the Rx DMA transfer when acting as flow controller */ if (quirks & DW_UART_QUIRK_IS_DMA_FC && up->dma && up->dma->rx_running && rx_timeout) { + spin_lock_irqsave(&p->lock, flags); status = serial_lsr_in(up); + spin_unlock_irqrestore(&p->lock, flags); + if (status & (UART_LSR_DR | UART_LSR_BI)) { dw8250_writel_ext(p, RZN1_UART_RDMACR, 0); dw8250_writel_ext(p, DW_UART_DMASA, 1); -- 2.30.2