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=-8.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS 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 590C2C433E0 for ; Tue, 9 Mar 2021 18:19:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1E4C1650F5 for ; Tue, 9 Mar 2021 18:19:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230522AbhCISTH (ORCPT ); Tue, 9 Mar 2021 13:19:07 -0500 Received: from mail-yb1-f178.google.com ([209.85.219.178]:35499 "EHLO mail-yb1-f178.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230490AbhCISTF (ORCPT ); Tue, 9 Mar 2021 13:19:05 -0500 Received: by mail-yb1-f178.google.com with SMTP id p186so14984363ybg.2; Tue, 09 Mar 2021 10:19:05 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=a5e+TdSdVNPIU4ahZflol/g+wKmqi90+UgljIBVqbKQ=; b=RuwMETu+HHPOC4sOzIE7AAgsiZwEvWW92kyEwHMrfMKhj6cPQceu0L5pFtyNNgT9FU PaJDOqQMy72cIFsYmdVzzPfzBaG310bV9kTP7vyxcHKhxWh58lhNIm/mFq2nPELEWuo9 DH6BUuoehK0zz1k9IGiEaRAX54TB6wsXj84HjX6UA97p06hPUqyBxfV9QS9sTCPJzkWd kynaFaBn+Bf4uPM2mMG6Zm81wA0TiLrKLkfGB2mcjNmbTC6McffMZdcomDlSdS/qgdDF 0FvWK6izsViICfjGcvYfgiRVJMQQrGquyH6jVjSz+TBh3jAU14Y9PrgpIWwmnFpMLURF en0g== X-Gm-Message-State: AOAM533t0141kWh5miw+0C5sA2HRBHjln/5Q00W3mIFjc7pIcmAoeItw HGXHCEfvQ3aeT2MZaiH29LJwToxyhS72uhSqDKA= X-Google-Smtp-Source: ABdhPJwADrymzS32Y4E2MTY/fV5tFgeE/xb8q0dhQZw5aN48jd58+Z+6W9vaPY2VkCWyXa5oWxZdNYGdDwJIct8Z0VA= X-Received: by 2002:a25:2c96:: with SMTP id s144mr25507702ybs.487.1615313944659; Tue, 09 Mar 2021 10:19:04 -0800 (PST) MIME-Version: 1.0 References: <20210309120946.1640-1-mailhol.vincent@wanadoo.fr> <20210309120946.1640-2-mailhol.vincent@wanadoo.fr> <45c0b0cc-bfd6-5180-7ad9-51eebc9de3c9@gmail.com> In-Reply-To: From: Vincent MAILHOL Date: Wed, 10 Mar 2021 03:18:53 +0900 Message-ID: Subject: Re: [RESEND v12] can: usb: etas_es58X: add support for ETAS ES58X CAN USB interfaces To: Jimmy Assarsson Cc: Arunachalam Santhanam , open list , Marc Kleine-Budde , linux-can Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-can@vger.kernel.org On Wed. 10 Mar 2021 at 03:11, Vincent MAILHOL wrote: > > On Wed. 10 Mar 2021 at 02:27, Jimmy Assarsson wrote: > > > > Hi Vincent, > > > > On 2021-03-09 13:09, Vincent Mailhol wrote: > > > This driver supports the ES581.4, ES582.1 and ES584.1 interfaces from > > > ETAS GmbH (https://www.etas.com/en/products/es58x.php). > > ... > > > diff --git a/drivers/net/can/usb/etas_es58x/es58x_core.c b/drivers/net/can/usb/etas_es58x/es58x_core.c > > > new file mode 100644 > > > index 000000000000..31f907a7b75f > > > --- /dev/null > > > +++ b/drivers/net/can/usb/etas_es58x/es58x_core.c > > ... > > > +/** > > > + * es58x_add_skb_idx() - Increment an index of the loopback FIFO. > > > + * @priv: ES58X private parameters related to the network device. > > > + * @idx: address of the index to be incremented. > > > + * @a: the increment. Must be positive and less or equal to > > > + * @priv->can.echo_skb_max. > > > + * > > > + * Do a modulus addition: set *@idx to (*@idx + @a) % > > > + * @priv->can.echo_skb_max. > > > + * > > > + * Rationale: the modulus operator % takes a decent amount of CPU > > > + * cycles (c.f. other division functions such as > > > + * include/linux/math64.h:iter_div_u64_rem()). > > > + */ > > > +static __always_inline void es58x_add_skb_idx(struct es58x_priv *priv, > > > + u16 *idx, u16 a) > > > > Never used? > > Indeed, this is a leftover. Should have been removed in v11 when I > made the device FIFO size a power of two. > I was not warned by the compiler, probably because this is an inline function. > > > ... > > > +/** > > > + * es58x_get_product_info() - Get the product information and print them. > > > + * @es58x_dev: ES58X device. > > > + * > > > + * Do a synchronous call to get the product information. > > > + * > > > + * Return: zero on success, errno when any error occurs. > > > + */ > > > +static int es58x_get_product_info(struct es58x_device *es58x_dev) > > > +{ > > > + struct usb_device *udev = es58x_dev->udev; > > > + const int es58x_prod_info_idx = 6; > > > + /* Empirical tests show a prod_info length of maximum 83, > > > + * below should be more than enough. > > > + */ > > > + const size_t prod_info_len = 127; > > > + char *prod_info; > > > + int ret; > > > + > > > + prod_info = kmalloc(prod_info_len, GFP_KERNEL); > > > + if (!prod_info) > > > + return -ENOMEM; > > > + > > > + ret = usb_string(udev, es58x_prod_info_idx, prod_info, prod_info_len); > > > + if (ret < 0) { > > > + dev_err(es58x_dev->dev, > > > + "%s: Could not read the product info: %pe\n", > > > + __func__, ERR_PTR(ret)); > > > > Missing free > > Absolutely! > > > > + return ret; > > > + } else if (ret >= prod_info_len - 1) { > > > + dev_warn(es58x_dev->dev, > > > + "%s: Buffer is too small, result might be truncated\n", > > > + __func__); > > > + } > > > + dev_info(es58x_dev->dev, "Product info: %s\n", prod_info); > > > + kfree(prod_info); > > > + > > > + return 0; > > > +} > > Thanks for the two findings, both will be fixed in v13. Out of curiosity, did you find the two issues throughout a code review or did you use any kind of static analysis tool?