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=-5.0 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,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 40BC8C433E0 for ; Thu, 28 May 2020 13:56:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 065AA20814 for ; Thu, 28 May 2020 13:56:29 +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="sKFpil8C" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390861AbgE1N42 (ORCPT ); Thu, 28 May 2020 09:56:28 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36856 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2390782AbgE1N4W (ORCPT ); Thu, 28 May 2020 09:56:22 -0400 Received: from mail-pg1-x544.google.com (mail-pg1-x544.google.com [IPv6:2607:f8b0:4864:20::544]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 71C6AC05BD1E for ; Thu, 28 May 2020 06:56:22 -0700 (PDT) Received: by mail-pg1-x544.google.com with SMTP id w20so8478366pga.6 for ; Thu, 28 May 2020 06:56:22 -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=NSCHZoX3QeqH6L33QAQLhgDcGYFDxPu6DWaF39Oa9XE=; b=sKFpil8CK1mMHL0wytcaK0eCTbjcqly0KJfRKCHmxGsrltR3p7+tY8llBnPMM3n4M9 4Z82hX8aVyKwfuyVfcVv8oA7fBF476wFDRnDfYXSiboeObDvMs2JxnIgu91FCha4hASv B/6lJRwsUw6agzKYNro1i4v35xulqIKR+KqPWq1qvWmjsM8uwnwuLqr9NdVpoyUa10DB sgc45aSwLdkuQnd0nGbD1LvHOvDfBvQV+C2AWYdSowdeebmAt8zykoVfgRlpJSKCc1gR j0dpU2u9pY7IIZZtEJjENrAbHRcZ4cRKZT4eKKz1iOR/aHGPEEWpVEBHDqfyD4QEvc6Z cNcg== 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=NSCHZoX3QeqH6L33QAQLhgDcGYFDxPu6DWaF39Oa9XE=; b=ZhBqW49vy1e5su3hGvWkV/SD4zp8oikoUdVsLpYHY9TInEA2i6vzcexP+q9JqBmV0E W9f35/ADgONzZzgq1VkZHBrlqvgy7U/zOPtQ/MjuvBriM7TtVzRloGC28DwI3IMPwBBX 6oHLF6y70c1UPr1oFp7wliL0cULYgcyP5RMcqU02szXSTPiLAdXHBmbY99jME+hfxzO7 HqcxW5dFfafBX2V4+Cz9N7DxWZpPdriOPrVFBm5l3XixYLuyRu3/915wd/eSSTspf56Q yKTIrWdkqHOJuSD9RkEqe0BommJ+S+0jV4LLYO7iLqnICbV+iN/sGvRtTqIuGWlCoq/2 v1QA== X-Gm-Message-State: AOAM532nxjM5tXXaUaxeRtCUz+SbvQFiIYv6EPikFssociasiSH0l7Kc z2q0Asftqv7FWwWqg3+FsQw= X-Google-Smtp-Source: ABdhPJxVntSWy1jUPnVWxdWn61wrqF/5+Id3Itcc4ZZKWDAFPpWG0veIyRazhT9F7qvjRZ5To2YQgQ== X-Received: by 2002:a63:482:: with SMTP id 124mr3062637pge.169.1590674181919; Thu, 28 May 2020 06:56:21 -0700 (PDT) Received: from server.roeck-us.net ([2600:1700:e321:62f0:329c:23ff:fee3:9d7c]) by smtp.gmail.com with ESMTPSA id 145sm4972007pfa.53.2020.05.28.06.56.20 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 28 May 2020 06:56:20 -0700 (PDT) Subject: Re: [PATCH 2/2] kobject: send KOBJ_REMOVE uevent when the object is removed from sysfs To: "Rafael J. Wysocki" Cc: "Rafael J. Wysocki" , Linux Kernel Mailing List , Heikki Krogerus , Greg Kroah-Hartman , Dmitry Torokhov References: <20200524153041.2361-1-gregkh@linuxfoundation.org> <20200527075048.GD3284396@kuha.fi.intel.com> <2407984.idRd5kzSG0@kreacher> <20200527222515.GA89212@roeck-us.net> 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: <64eb962a-eaef-9747-9408-eb9061cb42f6@roeck-us.net> Date: Thu, 28 May 2020 06:56:19 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.7.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 5/28/20 3:57 AM, Rafael J. Wysocki wrote: > On Thu, May 28, 2020 at 12:25 AM Guenter Roeck wrote: >> >> On Wed, May 27, 2020 at 11:01:16AM +0200, Rafael J. Wysocki wrote: >>> >>> So Guenter, can you please test the patch below to see if it still introduces >>> the problems seen by you on ARM? >>> >> >> arm64 and arm64be boot tests pass with the patch below. > > Great, thanks! > >> Some arm boot tests fail, but I think that is due to some other problem with -next. >> Hard to say for sure at this point because -next is pretty badly broken >> overall. I'll need to run some bisects to see what is going on. > > I see. > The failing arm boot tests are due to various dts changes (commit "arm64: dts: vexpress: Move fixed devices out of bus node" and associated), unrelated to this patch. Guenter > Thanks for giving this one a go. > >>> --- >>> From: Heikki Krogerus >>> Subject: [PATCH] kobject: Make sure the parent does not get released before its children >>> >>> In the function kobject_cleanup(), kobject_del(kobj) is >>> called before the kobj->release(). That makes it possible to >>> release the parent of the kobject before the kobject itself. >>> >>> To fix that, adding function __kboject_del() that does >>> everything that kobject_del() does except release the parent >>> reference. kobject_cleanup() then calls __kobject_del() >>> instead of kobject_del(), and separately decrements the >>> reference count of the parent kobject after kobj->release() >>> has been called. >>> >>> Reported-by: Naresh Kamboju >>> Reported-by: kernel test robot >>> Fixes: 7589238a8cf3 ("Revert "software node: Simplify software_node_release() function"") >>> Suggested-by: "Rafael J. Wysocki" >>> Signed-off-by: Heikki Krogerus >>> [ rjw: Drop parent reference only when called __kobject_del() ] >>> Signed-off-by: "Rafael J. Wysocki" >>> --- >>> lib/kobject.c | 34 +++++++++++++++++++++++----------- >>> 1 file changed, 23 insertions(+), 11 deletions(-) >>> >>> Index: linux-pm/lib/kobject.c >>> =================================================================== >>> --- linux-pm.orig/lib/kobject.c >>> +++ linux-pm/lib/kobject.c >>> @@ -599,14 +599,7 @@ out: >>> } >>> EXPORT_SYMBOL_GPL(kobject_move); >>> >>> -/** >>> - * kobject_del() - Unlink kobject from hierarchy. >>> - * @kobj: object. >>> - * >>> - * This is the function that should be called to delete an object >>> - * successfully added via kobject_add(). >>> - */ >>> -void kobject_del(struct kobject *kobj) >>> +static void __kobject_del(struct kobject *kobj) >>> { >>> struct kernfs_node *sd; >>> const struct kobj_type *ktype; >>> @@ -625,9 +618,23 @@ void kobject_del(struct kobject *kobj) >>> >>> kobj->state_in_sysfs = 0; >>> kobj_kset_leave(kobj); >>> - kobject_put(kobj->parent); >>> kobj->parent = NULL; >>> } >>> + >>> +/** >>> + * kobject_del() - Unlink kobject from hierarchy. >>> + * @kobj: object. >>> + * >>> + * This is the function that should be called to delete an object >>> + * successfully added via kobject_add(). >>> + */ >>> +void kobject_del(struct kobject *kobj) >>> +{ >>> + struct kobject *parent = kobj->parent; >>> + >>> + __kobject_del(kobj); >>> + kobject_put(parent); >>> +} >>> EXPORT_SYMBOL(kobject_del); >>> >>> /** >>> @@ -663,7 +670,9 @@ EXPORT_SYMBOL(kobject_get_unless_zero); >>> */ >>> static void kobject_cleanup(struct kobject *kobj) >>> { >>> + struct kobject *parent = kobj->parent; >>> struct kobj_type *t = get_ktype(kobj); >>> + bool state_in_sysfs = kobj->state_in_sysfs; >>> const char *name = kobj->name; >>> >>> pr_debug("kobject: '%s' (%p): %s, parent %p\n", >>> @@ -681,10 +690,10 @@ static void kobject_cleanup(struct kobje >>> } >>> >>> /* remove from sysfs if the caller did not do it */ >>> - if (kobj->state_in_sysfs) { >>> + if (state_in_sysfs) { >>> pr_debug("kobject: '%s' (%p): auto cleanup kobject_del\n", >>> kobject_name(kobj), kobj); >>> - kobject_del(kobj); >>> + __kobject_del(kobj); >>> } >>> >>> if (t && t->release) { >>> @@ -698,6 +707,9 @@ static void kobject_cleanup(struct kobje >>> pr_debug("kobject: '%s': free name\n", name); >>> kfree_const(name); >>> } >>> + >>> + if (state_in_sysfs) >>> + kobject_put(parent); >>> } >>> >>> #ifdef CONFIG_DEBUG_KOBJECT_RELEASE >>> >>> >>>