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=-8.3 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=ham 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 5BAA2C433E0 for ; Thu, 2 Jul 2020 14:29:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 255EC20772 for ; Thu, 2 Jul 2020 14:29:36 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="EG/j8YLj" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729643AbgGBO3f (ORCPT ); Thu, 2 Jul 2020 10:29:35 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47516 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729551AbgGBO3f (ORCPT ); Thu, 2 Jul 2020 10:29:35 -0400 Received: from mail-pg1-x542.google.com (mail-pg1-x542.google.com [IPv6:2607:f8b0:4864:20::542]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3D133C08C5C1; Thu, 2 Jul 2020 07:29:35 -0700 (PDT) Received: by mail-pg1-x542.google.com with SMTP id t6so13571275pgq.1; Thu, 02 Jul 2020 07:29:35 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:subject:to:cc:references:from:autocrypt:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=czvVKKthPilSzIMJGceb961oxazjTLTdw4Ktc9MAzhM=; b=EG/j8YLjr+MNqDG5m+F1H9InIZqLPRFw5KZa+5nLwKxIUwMm0B+yxtuHZCQiTFisEg iAAjGEQqTcFiZnfqRLihC2WQfkYY+mKeGJ20AdGnHYHuLCo5pSVnixfWiK0yDZWzEWcP Mjdm1diNIn1wGjNPdi9Hvctf7DZhnauf9JqS4XVFbF2/hJfllDlA1wEWWMQ4YfgtSm4w HS8FYSNJtaIzWV1twfT8ndS8HmOtOoMH8k6UXK/6xl2pvvVyxLIFpRPPu/OWx/0pnOYw bhHfIVbnTapw4YOt63Q23XC/+dgU6pgEABf74jSaSTaSryttIPMnEJXTBrwg2f7RNKpw yVig== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:subject:to:cc:references:from:autocrypt :message-id:date:user-agent:mime-version:in-reply-to :content-language:content-transfer-encoding; bh=czvVKKthPilSzIMJGceb961oxazjTLTdw4Ktc9MAzhM=; b=uKN2mC6nN4GoCwnUlxoF1j9iK8U80yp3s0llqGU0IJQmNes1aPqKOjFq51t+o6bf31 /eR2USqpb+EoJqSamiMWTsqO6Kx5XCA69bsQX33RIOOxid5UfYfuvyIgHv/K3h1weRa9 1WNexnpNnREo9SQKlKSl02Gp8UzywDPimzb9O8dEkD5cLKWbNDQEFkZdjgCmwNAFApif bcqrrDXKF0oW66jPR3++jPlJWNZzuxjTHZ2r1kb4/LxM8Im7mIotnTgEWLmI4SizVL3a Y/wK01lS3ExxMV3LDCzArjHJMsGShn97NMhDoFEpQyTNjNJpCWAoOY1ffY4DlvWYwQDn C+6g== X-Gm-Message-State: AOAM5303Vd1AOHmrUip5T8uwAu7qTzijGZwhdiDtM53RVHpjulNpt9FK QeCW3KTJfEIMyRtwYOz66nc= X-Google-Smtp-Source: ABdhPJwZFdMOqmXi9eUfscWH+t+1XxSSEbww2D5jNJB2UkFrI4zmMmjEFBsPFMMFbAmH4Z0hiAAaXg== X-Received: by 2002:a62:1790:: with SMTP id 138mr27394161pfx.306.1593700174674; Thu, 02 Jul 2020 07:29:34 -0700 (PDT) Received: from server.roeck-us.net ([2600:1700:e321:62f0:329c:23ff:fee3:9d7c]) by smtp.gmail.com with ESMTPSA id q36sm8190876pjq.18.2020.07.02.07.29.33 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 02 Jul 2020 07:29:34 -0700 (PDT) Subject: Re: [PATCH v2 6/6] hwmon: pmbus: use more devres helpers To: Greg Kroah-Hartman , Bartosz Golaszewski Cc: Jonathan Corbet , "Rafael J . Wysocki" , Jean Delvare , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-hwmon@vger.kernel.org, Bartosz Golaszewski References: <20200629065008.27620-1-brgl@bgdev.pl> <20200629065008.27620-7-brgl@bgdev.pl> <20200702124419.GB1882489@kroah.com> From: Guenter Roeck Autocrypt: addr=linux@roeck-us.net; keydata= xsFNBE6H1WcBEACu6jIcw5kZ5dGeJ7E7B2uweQR/4FGxH10/H1O1+ApmcQ9i87XdZQiB9cpN RYHA7RCEK2dh6dDccykQk3bC90xXMPg+O3R+C/SkwcnUak1UZaeK/SwQbq/t0tkMzYDRxfJ7 nyFiKxUehbNF3r9qlJgPqONwX5vJy4/GvDHdddSCxV41P/ejsZ8PykxyJs98UWhF54tGRWFl 7i1xvaDB9lN5WTLRKSO7wICuLiSz5WZHXMkyF4d+/O5ll7yz/o/JxK5vO/sduYDIlFTvBZDh gzaEtNf5tQjsjG4io8E0Yq0ViobLkS2RTNZT8ICq/Jmvl0SpbHRvYwa2DhNsK0YjHFQBB0FX IdhdUEzNefcNcYvqigJpdICoP2e4yJSyflHFO4dr0OrdnGLe1Zi/8Xo/2+M1dSSEt196rXaC kwu2KgIgmkRBb3cp2vIBBIIowU8W3qC1+w+RdMUrZxKGWJ3juwcgveJlzMpMZNyM1jobSXZ0 VHGMNJ3MwXlrEFPXaYJgibcg6brM6wGfX/LBvc/haWw4yO24lT5eitm4UBdIy9pKkKmHHh7s jfZJkB5fWKVdoCv/omy6UyH6ykLOPFugl+hVL2Prf8xrXuZe1CMS7ID9Lc8FaL1ROIN/W8Vk BIsJMaWOhks//7d92Uf3EArDlDShwR2+D+AMon8NULuLBHiEUQARAQABzTJHdWVudGVyIFJv ZWNrIChMaW51eCBhY2NvdW50KSA8bGludXhAcm9lY2stdXMubmV0PsLBgQQTAQIAKwIbAwYL CQgHAwIGFQgCCQoLBBYCAwECHgECF4ACGQEFAlVcphcFCRmg06EACgkQyx8mb86fmYFg0RAA nzXJzuPkLJaOmSIzPAqqnutACchT/meCOgMEpS5oLf6xn5ySZkl23OxuhpMZTVX+49c9pvBx hpvl5bCWFu5qC1jC2eWRYU+aZZE4sxMaAGeWenQJsiG9lP8wkfCJP3ockNu0ZXXAXwIbY1O1 c+l11zQkZw89zNgWgKobKzrDMBFOYtAh0pAInZ9TSn7oA4Ctejouo5wUugmk8MrDtUVXmEA9 7f9fgKYSwl/H7dfKKsS1bDOpyJlqhEAH94BHJdK/b1tzwJCFAXFhMlmlbYEk8kWjcxQgDWMu GAthQzSuAyhqyZwFcOlMCNbAcTSQawSo3B9yM9mHJne5RrAbVz4TWLnEaX8gA5xK3uCNCeyI sqYuzA4OzcMwnnTASvzsGZoYHTFP3DQwf2nzxD6yBGCfwNGIYfS0i8YN8XcBgEcDFMWpOQhT Pu3HeztMnF3HXrc0t7e5rDW9zCh3k2PA6D2NV4fews9KDFhLlTfCVzf0PS1dRVVWM+4jVl6l HRIAgWp+2/f8dx5vPc4Ycp4IsZN0l1h9uT7qm1KTwz+sSl1zOqKD/BpfGNZfLRRxrXthvvY8 BltcuZ4+PGFTcRkMytUbMDFMF9Cjd2W9dXD35PEtvj8wnEyzIos8bbgtLrGTv/SYhmPpahJA l8hPhYvmAvpOmusUUyB30StsHIU2LLccUPPOwU0ETofVZwEQALlLbQeBDTDbwQYrj0gbx3bq 7kpKABxN2MqeuqGr02DpS9883d/t7ontxasXoEz2GTioevvRmllJlPQERVxM8gQoNg22twF7 pB/zsrIjxkE9heE4wYfN1AyzT+AxgYN6f8hVQ7Nrc9XgZZe+8IkuW/Nf64KzNJXnSH4u6nJM J2+Dt274YoFcXR1nG76Q259mKwzbCukKbd6piL+VsT/qBrLhZe9Ivbjq5WMdkQKnP7gYKCAi pNVJC4enWfivZsYupMd9qn7Uv/oCZDYoBTdMSBUblaLMwlcjnPpOYK5rfHvC4opxl+P/Vzyz 6WC2TLkPtKvYvXmdsI6rnEI4Uucg0Au/Ulg7aqqKhzGPIbVaL+U0Wk82nz6hz+WP2ggTrY1w ZlPlRt8WM9w6WfLf2j+PuGklj37m+KvaOEfLsF1v464dSpy1tQVHhhp8LFTxh/6RWkRIR2uF I4v3Xu/k5D0LhaZHpQ4C+xKsQxpTGuYh2tnRaRL14YMW1dlI3HfeB2gj7Yc8XdHh9vkpPyuT nY/ZsFbnvBtiw7GchKKri2gDhRb2QNNDyBnQn5mRFw7CyuFclAksOdV/sdpQnYlYcRQWOUGY HhQ5eqTRZjm9z+qQe/T0HQpmiPTqQcIaG/edgKVTUjITfA7AJMKLQHgp04Vylb+G6jocnQQX JqvvP09whbqrABEBAAHCwWUEGAECAA8CGwwFAlVcpi8FCRmg08MACgkQyx8mb86fmYHNRQ/+ J0OZsBYP4leJvQF8lx9zif+v4ZY/6C9tTcUv/KNAE5leyrD4IKbnV4PnbrVhjq861it/zRQW cFpWQszZyWRwNPWUUz7ejmm9lAwPbr8xWT4qMSA43VKQ7ZCeTQJ4TC8kjqtcbw41SjkjrcTG wF52zFO4bOWyovVAPncvV9eGA/vtnd3xEZXQiSt91kBSqK28yjxAqK/c3G6i7IX2rg6pzgqh hiH3/1qM2M/LSuqAv0Rwrt/k+pZXE+B4Ud42hwmMr0TfhNxG+X7YKvjKC+SjPjqp0CaztQ0H nsDLSLElVROxCd9m8CAUuHplgmR3seYCOrT4jriMFBtKNPtj2EE4DNV4s7k0Zy+6iRQ8G8ng QjsSqYJx8iAR8JRB7Gm2rQOMv8lSRdjva++GT0VLXtHULdlzg8VjDnFZ3lfz5PWEOeIMk7Rj trjv82EZtrhLuLjHRCaG50OOm0hwPSk1J64R8O3HjSLdertmw7eyAYOo4RuWJguYMg5DRnBk WkRwrSuCn7UG+qVWZeKEsFKFOkynOs3pVbcbq1pxbhk3TRWCGRU5JolI4ohy/7JV1TVbjiDI HP/aVnm6NC8of26P40Pg8EdAhajZnHHjA7FrJXsy3cyIGqvg9os4rNkUWmrCfLLsZDHD8FnU mDW4+i+XlNFUPUYMrIKi9joBhu18ssf5i5Q= Message-ID: <432eb32c-3991-d001-29f9-e98389b9a7a6@roeck-us.net> Date: Thu, 2 Jul 2020 07:29:32 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.8.0 MIME-Version: 1.0 In-Reply-To: <20200702124419.GB1882489@kroah.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit Sender: linux-hwmon-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-hwmon@vger.kernel.org On 7/2/20 5:44 AM, Greg Kroah-Hartman wrote: > On Mon, Jun 29, 2020 at 08:50:08AM +0200, Bartosz Golaszewski wrote: >> From: Bartosz Golaszewski >> >> Shrink pmbus code by using devm_hwmon_device_register_with_groups() >> and devm_krealloc() instead of their non-managed variants. >> >> Signed-off-by: Bartosz Golaszewski >> --- >> drivers/hwmon/pmbus/pmbus_core.c | 28 +++++++++------------------- >> 1 file changed, 9 insertions(+), 19 deletions(-) >> >> diff --git a/drivers/hwmon/pmbus/pmbus_core.c b/drivers/hwmon/pmbus/pmbus_core.c >> index a420877ba533..225d0ac162c7 100644 >> --- a/drivers/hwmon/pmbus/pmbus_core.c >> +++ b/drivers/hwmon/pmbus/pmbus_core.c >> @@ -1022,9 +1022,9 @@ static int pmbus_add_attribute(struct pmbus_data *data, struct attribute *attr) >> { >> if (data->num_attributes >= data->max_attributes - 1) { >> int new_max_attrs = data->max_attributes + PMBUS_ATTR_ALLOC_SIZE; >> - void *new_attrs = krealloc(data->group.attrs, >> - new_max_attrs * sizeof(void *), >> - GFP_KERNEL); >> + void *new_attrs = devm_krealloc(data->dev, data->group.attrs, >> + new_max_attrs * sizeof(void *), >> + GFP_KERNEL); > > dynamic sysfs attributes in a devm-allocated chunk of memory? What > could go wrong... > You mean that the memory might be removed before the attributes are removed ? Hmm, but that isn't different to the current implementation. The hwmon device is removed first (removing the sysfs attributes), followed by the kfree. Are you saying this is not safe ? Pretty much all code which allocates memory for struct attribute is doing the same, so that would be a problem throughout the kernel. > Anyway, is this the only in-kernel user that you could find for this > function? If so, it feels like it's a lot of extra work for no real > gain. > And I was so happy that I'd be able to get rid of pmbus_do_remove() subsequently. But then I can also use devm_add_action() and have it call kfree(), with the same result. Given that, if hwmon would really be the only user, we can live without it. Guenter