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=-9.0 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,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 50F73C433DB for ; Wed, 24 Mar 2021 05:45:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 043AB619E9 for ; Wed, 24 Mar 2021 05:45:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235232AbhCXFon (ORCPT ); Wed, 24 Mar 2021 01:44:43 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48868 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233070AbhCXFoa (ORCPT ); Wed, 24 Mar 2021 01:44:30 -0400 Received: from mail-pj1-x102b.google.com (mail-pj1-x102b.google.com [IPv6:2607:f8b0:4864:20::102b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 09FB4C061763 for ; Tue, 23 Mar 2021 22:44:30 -0700 (PDT) Received: by mail-pj1-x102b.google.com with SMTP id j6-20020a17090adc86b02900cbfe6f2c96so591646pjv.1 for ; Tue, 23 Mar 2021 22:44:29 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=vZyzdZb7zClnWDp32yie1Io/7W63y0skPKX8iMwls/I=; b=FK9lVBFUYOCv1pVKWo5qZKBE7q5MZdByu7qUuLKc+azdMNFbGKAJUs9+SM5AKQa0l4 tvePM4g+hmsChf/du3SKhKtoSnkmc+l/QklFMrrsgvx1hFPVmrE9uZ34B3yk5XWZz7Nc 7zHFXMjI79KywH+FltRITP6LxldrBo1a6WsRwiRUUvjrGGwCX45ssmmKunuiL3i6tlfL 7iskn1Z28173rlaVxT00kO/WluYYHHZgZiS0fqBKvXL7h/LhStzSwWnlPiW4hqLcGyAm 6iubQAWD8jc9WZK4Vk9CLE1iPhljsKHkIFT5kM24G4sB7CewxYIrE6d+DASSeGoZHdFO PjFg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:from:to:cc:subject:message-id :references:mime-version:content-disposition:in-reply-to; bh=vZyzdZb7zClnWDp32yie1Io/7W63y0skPKX8iMwls/I=; b=AnHL8lNwpuZ5tzDHt2rgcYvMP/9s/3nc/khcLFDOATYrKVnP109M/71a2Kb15FKkdL 2ep8bAQWIMy1mlrLZpMehObjTCfBdzoJ0lGKv4NVVRrO4XakJZqaIQDKcyE30XBAxaf5 sZABWaeaJ7IYS2wLUkBrZCZ8jbUr7bVE9uFWzfHJXfe0g+Pd4MF8Zks8k5ccjaH/q7w0 cnVEGV/js/JiadN48EnfZnYEtwHabLjH8j5VXtpss+SRKPgIPkirBBI5/QwHMiDNgx1g QrWrkGIHIogmqvBcJ9aCKQNfJvjgxFUyMqYKHKf+WyEBGbvEYqAmWQwBrbE51W3YRWW1 WygQ== X-Gm-Message-State: AOAM533/1gI2d84smViVuEQWQONnuUJf1yVpOEbTFFFEiu4YtRLZL9DE P8+HYWw3Upr4v54CfzBlR34= X-Google-Smtp-Source: ABdhPJyzIF43r33U3LY2waAoqsy4NnUMSYlMYaSs310IbR5TDbHauQR0UJ4Teis3BamXoBW69N579Q== X-Received: by 2002:a17:90b:3884:: with SMTP id mu4mr1722306pjb.128.1616564669395; Tue, 23 Mar 2021 22:44:29 -0700 (PDT) Received: from google.com ([2620:15c:211:201:7dfa:1e53:536:7976]) by smtp.gmail.com with ESMTPSA id d8sm1013356pfq.27.2021.03.23.22.44.27 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 23 Mar 2021 22:44:28 -0700 (PDT) Sender: Minchan Kim Date: Tue, 23 Mar 2021 22:44:26 -0700 From: Minchan Kim To: John Hubbard Cc: Andrew Morton , linux-mm , LKML , gregkh@linuxfoundation.org, surenb@google.com, joaodias@google.com, willy@infradead.org, digetx@gmail.com Subject: Re: [PATCH v6] mm: cma: support sysfs Message-ID: References: <20210324010547.4134370-1-minchan@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Mar 23, 2021 at 09:47:27PM -0700, John Hubbard wrote: > On 3/23/21 8:27 PM, Minchan Kim wrote: > ... > > > > +static int __init cma_sysfs_init(void) > > > > +{ > > > > + unsigned int i; > > > > + > > > > + cma_kobj_root = kobject_create_and_add("cma", mm_kobj); > > > > + if (!cma_kobj_root) > > > > + return -ENOMEM; > > > > + > > > > + for (i = 0; i < cma_area_count; i++) { > > > > + int err; > > > > + struct cma *cma; > > > > + struct cma_kobject *cma_kobj; > > > > + > > > > + cma_kobj = kzalloc(sizeof(*cma_kobj), GFP_KERNEL); > > > > + if (!cma_kobj) { > > > > + kobject_put(cma_kobj_root); > > > > + return -ENOMEM; > > > > > > This leaks little cma_kobj's all over the floor. :) > > > > I thought kobject_put(cma_kobj_root) should deal with it. No? > > > If this fails when i > 0, there will be cma_kobj instances that > were stashed in the cma_areas[] array. But this code only deletes > the most recently allocated cma_kobj, not anything allocated on > previous iterations of the loop. Oh, I misunderstood that destroying of root kobject will release children recursively. Seems not true. Go back to old version. index 16c81c9cb9b7..418951a3f138 100644 --- a/mm/cma_sysfs.c +++ b/mm/cma_sysfs.c @@ -80,20 +80,19 @@ static struct kobj_type cma_ktype = { static int __init cma_sysfs_init(void) { unsigned int i; + int err; + struct cma *cma; + struct cma_kobject *cma_kobj; cma_kobj_root = kobject_create_and_add("cma", mm_kobj); if (!cma_kobj_root) return -ENOMEM; for (i = 0; i < cma_area_count; i++) { - int err; - struct cma *cma; - struct cma_kobject *cma_kobj; - cma_kobj = kzalloc(sizeof(*cma_kobj), GFP_KERNEL); if (!cma_kobj) { - kobject_put(cma_kobj_root); - return -ENOMEM; + err = -ENOMEM; + goto out; } cma = &cma_areas[i]; @@ -103,11 +102,21 @@ static int __init cma_sysfs_init(void) cma_kobj_root, "%s", cma->name); if (err) { kobject_put(&cma_kobj->kobj); - kobject_put(cma_kobj_root); - return err; + goto out; } } return 0; +out: + while (--i >= 0) { + cma = &cma_areas[i]; + + kobject_put(&cma->kobj->kobj); + kfree(cma->kobj); + cma->kobj = NULL; + } + kobject_put(cma_kobj_root); + + return err; } subsys_initcall(cma_sysfs_init);