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=-15.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable 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 8AAADC4708A for ; Thu, 27 May 2021 11:06:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5DDEC60241 for ; Thu, 27 May 2021 11:06:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233521AbhE0LH6 (ORCPT ); Thu, 27 May 2021 07:07:58 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58268 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232381AbhE0LH4 (ORCPT ); Thu, 27 May 2021 07:07:56 -0400 Received: from mail-wm1-x335.google.com (mail-wm1-x335.google.com [IPv6:2a00:1450:4864:20::335]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 87526C061760 for ; Thu, 27 May 2021 04:06:21 -0700 (PDT) Received: by mail-wm1-x335.google.com with SMTP id u4-20020a05600c00c4b02901774b80945cso2334577wmm.3 for ; Thu, 27 May 2021 04:06:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:content-transfer-encoding:in-reply-to; bh=ummK6qfHHovxgsh1qAiAuit2Ah0G9hijqJN9zZVv1/0=; b=y32EG0ZeB5pHnaFFE4hd3qjmELxCKWPasGNhZVK2KNPfjsmZjnOVJxKGniO03vuQ7E 58U2S8SiSp6qPG/R7EfiWnJnWPTySvr65KmGiOq4Te5SWv6I0/9QpSo5WDsxE8ShUdt5 qlu/E9ZSnbWC86PJwYn0HIcwy2LD/6zqEG9Dvnde5mjgIJAPLI0yUrwKmG40fVGigpwl 2csdVxTSZUqkfXvC5wlSZsyO7NYy0aBBb1pjd2pHy4eIdG2nnFpzM9ALSHNPy5UtXboo GAVObA2n3XAAPrlJrPOE30mSHymCpotbb0v8hwe/XE9ZjwK9vKyrNlmWPkmGPqoX8LdE lanQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:content-transfer-encoding :in-reply-to; bh=ummK6qfHHovxgsh1qAiAuit2Ah0G9hijqJN9zZVv1/0=; b=MvItpq/foRekZUMjt1x1QJaeHzAsuyp9sj+Wzn+OLgJVmscktS8k7QlSswcxJJYGE1 gcd6CojL9Dp8rKkx/6GmrGEl9a1a69xrPD8aDHSuZaalJMzXxZj4jxnreGbPZPd2h7sG FVpHH6DrqBbilcIySGLy+6GZFWrM0iuQW8JUtqR8s4Kwud8tBlPE4fwkfZK+JFsbpGtv XE2lkSFuP0chYejR4pDR6gylAwud0/MYdyE3GDLBfTbs2/DVOCNNjnrSkB+gEtxQlYze Uulp8c6Q+5fQ45ZWi3XJustNv2+eTfqO243s0od+lvNgsp/wchMaiFVmdfWCYKTqTUIv UTeA== X-Gm-Message-State: AOAM5332hpzSzSSRtaY2d0TjRDjfYUPghrwRpd2Nn2JoP0cwuXMvsOOc shwCiLdjW0q0ZdzI7dcp9dElCQ== X-Google-Smtp-Source: ABdhPJxUkvVSOzieXINUUjbfGicjBFU/rPCLLdCo5DfT0V4Cs7PwsidbIX5NjFxx4+fN8wKazUYGjA== X-Received: by 2002:a1c:f70d:: with SMTP id v13mr2771652wmh.183.1622113580028; Thu, 27 May 2021 04:06:20 -0700 (PDT) Received: from dell ([91.110.221.223]) by smtp.gmail.com with ESMTPSA id x2sm2381237wmj.3.2021.05.27.04.06.15 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 27 May 2021 04:06:19 -0700 (PDT) Date: Thu, 27 May 2021 12:06:11 +0100 From: Lee Jones To: Mathias Nyman Cc: Greg Kroah-Hartman , linux-kernel@vger.kernel.org, Mathias Nyman , linux-usb@vger.kernel.org Subject: Re: [PATCH 17/24] usb: host: xhci: Remove unused variable 'len' Message-ID: <20210527110611.GK543307@dell> References: <20210526130037.856068-1-lee.jones@linaro.org> <20210526130037.856068-18-lee.jones@linaro.org> <20210527081609.GF543307@dell> <5958f870-1834-3132-a729-2b26a84349ea@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <5958f870-1834-3132-a729-2b26a84349ea@linux.intel.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 27 May 2021, Mathias Nyman wrote: > On 27.5.2021 11.16, Lee Jones wrote: > > On Thu, 27 May 2021, Greg Kroah-Hartman wrote: > > > >> On Wed, May 26, 2021 at 02:00:30PM +0100, Lee Jones wrote: > >>> Fixes the following W=1 kernel build warning(s): > >>> > >>> drivers/usb/host/xhci.c: In function ‘xhci_unmap_temp_buf’: > >>> drivers/usb/host/xhci.c:1349:15: warning: variable ‘len’ set but not used [-Wunused-but-set-variable] > >>> > >>> Cc: Mathias Nyman > >>> Cc: Greg Kroah-Hartman > >>> Cc: linux-usb@vger.kernel.org > >>> Signed-off-by: Lee Jones > >>> --- > >>> drivers/usb/host/xhci.c | 9 ++++----- > >>> 1 file changed, 4 insertions(+), 5 deletions(-) > >>> > >>> diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c > >>> index 27283654ca080..ac2a7d4288883 100644 > >>> --- a/drivers/usb/host/xhci.c > >>> +++ b/drivers/usb/host/xhci.c > >>> @@ -1346,7 +1346,6 @@ static bool xhci_urb_temp_buffer_required(struct usb_hcd *hcd, > >>> > >>> static void xhci_unmap_temp_buf(struct usb_hcd *hcd, struct urb *urb) > >>> { > >>> - unsigned int len; > >>> unsigned int buf_len; > >>> enum dma_data_direction dir; > >>> > >>> @@ -1362,10 +1361,10 @@ static void xhci_unmap_temp_buf(struct usb_hcd *hcd, struct urb *urb) > >>> dir); > >>> > >>> if (usb_urb_dir_in(urb)) > >>> - len = sg_pcopy_from_buffer(urb->sg, urb->num_sgs, > >>> - urb->transfer_buffer, > >>> - buf_len, > >>> - 0); > >>> + sg_pcopy_from_buffer(urb->sg, urb->num_sgs, > >>> + urb->transfer_buffer, > >>> + buf_len, > >>> + 0); > >> > >> Sorry, but no, I keep rejecting this over and over, it needs to handle > >> the error handling properly and not paper over it like this :( > > > > Will fix. > > > >> All the bots keep tripping up on it, you are not alone. > > > > This is getting a lot of attention. Something like this should fix it: > > diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c > index 27283654ca08..306ab81421fd 100644 > --- a/drivers/usb/host/xhci.c > +++ b/drivers/usb/host/xhci.c > @@ -1361,12 +1361,16 @@ static void xhci_unmap_temp_buf(struct usb_hcd *hcd, struct urb *urb) > urb->transfer_buffer_length, > dir); > > - if (usb_urb_dir_in(urb)) > + if (usb_urb_dir_in(urb)) { > len = sg_pcopy_from_buffer(urb->sg, urb->num_sgs, > urb->transfer_buffer, > buf_len, > 0); > - > + if (len != buf_len) { > + xhci_dbg(xhci, "Copy from tmp buf to urb sg list failed\n"); > + urb->actual_length = len; > + } > + } > urb->transfer_flags &= ~URB_DMA_MAP_SINGLE; > kfree(urb->transfer_buffer); > urb->transfer_buffer = NULL; > > urb->actual_length is now properly set. > The debug level message will help me find the cause if we ever need > to debug oddly behaving devices. > > Note this is a very rarly taken codepath for quirky xHC harware that > can't handle a specific sequence of buffer lengths queued. > > I can write a proper commit message and push this forward Okay by me. -- Lee Jones [李琼斯] Senior Technical Lead - Developer Services Linaro.org │ Open source software for Arm SoCs Follow Linaro: Facebook | Twitter | Blog