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 CBDB8C433EF for ; Tue, 28 Jun 2022 10:57:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1345119AbiF1K5J (ORCPT ); Tue, 28 Jun 2022 06:57:09 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54158 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231682AbiF1K5F (ORCPT ); Tue, 28 Jun 2022 06:57:05 -0400 Received: from mga12.intel.com (mga12.intel.com [192.55.52.136]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DF67331DC0; Tue, 28 Jun 2022 03:57:04 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1656413824; x=1687949824; h=date:from:to:cc:subject:message-id:references: mime-version:content-transfer-encoding:in-reply-to; bh=WKpsfZrkq24GzM+XFoOF1PmMcAsmja+uPPVG+NvAxaw=; b=Imkz2nsV9eKCI7BX1unDdSq/k13hlBrHNaxOpbgUp1fCjbvMPkpm0fW0 erXzMZ3NggB79LHC/+5O33QNGxEGUDxiB6W6uotCmoiD51tuWxViX3E4l Ew72HIF599e2nmf+vYFU+YyPeXg4YOyeoIAzu91echoQjlJQEYjUbG+Ah Jb4Svfiu8NLy50l6l8q4vjgCFa79WsrHzMnlg2FL42IHBuI7c1Jh/Pt8m OFZJuArSN0gA5RuuoDPP757YCc2e54WvJ3LTg4HPv+EOs5zQkePvJVtzJ 95dm/gDVLwQVGFSbfANmV1ztGzMuRfdz+GUCFM6JQDBF8DvMVbxfIhEtv g==; X-IronPort-AV: E=McAfee;i="6400,9594,10391"; a="261511873" X-IronPort-AV: E=Sophos;i="5.92,227,1650956400"; d="scan'208";a="261511873" Received: from orsmga007.jf.intel.com ([10.7.209.58]) by fmsmga106.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 28 Jun 2022 03:57:04 -0700 X-IronPort-AV: E=Sophos;i="5.92,227,1650956400"; d="scan'208";a="587829952" Received: from smile.fi.intel.com ([10.237.72.54]) by orsmga007-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 28 Jun 2022 03:57:02 -0700 Received: from andy by smile.fi.intel.com with local (Exim 4.95) (envelope-from ) id 1o68tv-000wkA-R2; Tue, 28 Jun 2022 13:56:59 +0300 Date: Tue, 28 Jun 2022 13:56:59 +0300 From: Andy Shevchenko To: Ilpo =?iso-8859-1?Q?J=E4rvinen?= Cc: Greg KH , linux-serial , Jiri Slaby , LKML Subject: Re: [PATCH RESEND tty-next] serial: 8250_dw: Take port lock while accessing LSR Message-ID: References: MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jun 28, 2022 at 12:01:28PM +0300, Ilpo Järvinen wrote: > Accessing LSR requires port lock because it mutates lsr_saved_flags > in serial_lsr_in(). Don't remember if I given or not (and why if not) the tag, so here it is: Reviewed-by: Andy Shevchenko > Fixes: 197eb5c416ff ("serial: 8250_dw: Use serial_lsr_in() in dw8250_handle_irq()") > Signed-off-by: Ilpo Järvinen > > --- > I'll resend the third patch later. > > 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 167a691c7b19..f78b13db1b1e 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); > > -- > tg: (f55d2e4b0a47..) dw/use-spinlock (depends on: 8250/fix-stop_tx-race) -- With Best Regards, Andy Shevchenko