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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9332EC433EF for ; Mon, 15 Nov 2021 15:58:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6A283619E8 for ; Mon, 15 Nov 2021 15:58:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232375AbhKOQBe (ORCPT ); Mon, 15 Nov 2021 11:01:34 -0500 Received: from mail.kernel.org ([198.145.29.99]:59558 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232362AbhKOQBP (ORCPT ); Mon, 15 Nov 2021 11:01:15 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id C8BA9619E8; Mon, 15 Nov 2021 15:58:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1636991900; bh=6ObChIFYaBXn4SrtM0fzLgR5LrUgX/Hu5OOpSd/gAxQ=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=fhhI0RWAvBYQAGQKvKrKkCqPOFOB/go4eCNDSI2GqTkpqkSoXznmq5xf4lmLBqRaM YYKG5fxg8iaAyyiTcMjlAz7v6WGbIGcfI9nnZ7I3GonmfzPCUHHRIHAdWUICgSd3TA oc/xP77m+KUnuHo6yiNQb4ZnBYEg5WfyYbxpHfcM= Date: Mon, 15 Nov 2021 16:58:17 +0100 From: Greg KH To: Tudor Ambarus Cc: richard.genoud@gmail.com, jirislaby@kernel.org, nicolas.ferre@microchip.com, alexandre.belloni@bootlin.com, ludovic.desroches@microchip.com, linux-serial@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] tty: serial: atmel: Check return code of dmaengine_submit() Message-ID: References: <20211115143004.32743-1-tudor.ambarus@microchip.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20211115143004.32743-1-tudor.ambarus@microchip.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Nov 15, 2021 at 04:30:04PM +0200, Tudor Ambarus wrote: > dma_cookie_t < 0 indicates an error code, check for it. Very odd changelog text, please be more descriptive about what is happening here. > > Signed-off-by: Tudor Ambarus > --- > drivers/tty/serial/atmel_serial.c | 10 ++++++++++ > 1 file changed, 10 insertions(+) > > diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c > index 2c99a47a2535..376f7a9c2868 100644 > --- a/drivers/tty/serial/atmel_serial.c > +++ b/drivers/tty/serial/atmel_serial.c > @@ -1004,6 +1004,11 @@ static void atmel_tx_dma(struct uart_port *port) > desc->callback = atmel_complete_tx_dma; > desc->callback_param = atmel_port; > atmel_port->cookie_tx = dmaengine_submit(desc); > + if (dma_submit_error(atmel_port->cookie_tx)) { > + dev_err(port->dev, "dma_submit_error %d\n", > + atmel_port->cookie_tx); > + return; What can a user do with this error message? Have you seen this happen in real life? What commit does this "fix"? thanks, greg k-h