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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 97EB1C35280 for ; Mon, 7 Feb 2022 14:46:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1382771AbiBGOn3 (ORCPT ); Mon, 7 Feb 2022 09:43:29 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45462 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1441840AbiBGOdj (ORCPT ); Mon, 7 Feb 2022 09:33:39 -0500 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id C4A37C0401C1 for ; Mon, 7 Feb 2022 06:33:38 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1644244417; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=DooD/eUQIOsSU0GuUs2p2pfvlueEe65OpvoCl34gtw8=; b=hdwdP0jlo7MejfflofK37s03V47uemtSnt9pjX87XVdHHA9LvnXhNCB97J0L6OEwq8i61x F1kayMaDTmmH0i8Wr1LbbpuRvkVg7igNOTYZzVudUIQs7+921CPwPce5/2YFO4NAvqN7Cs Y8yZzxVrygosJfHBaJGzkb79b5ncgUM= Received: from mail-wm1-f72.google.com (mail-wm1-f72.google.com [209.85.128.72]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-5-89983t8LMgyh3AWiTGAiaw-1; Mon, 07 Feb 2022 09:33:36 -0500 X-MC-Unique: 89983t8LMgyh3AWiTGAiaw-1 Received: by mail-wm1-f72.google.com with SMTP id n3-20020a05600c294300b0037bc685b717so1637294wmd.8 for ; Mon, 07 Feb 2022 06:33:36 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:message-id:date:mime-version:user-agent:subject :content-language:to:cc:references:from:organization:in-reply-to :content-transfer-encoding; bh=DooD/eUQIOsSU0GuUs2p2pfvlueEe65OpvoCl34gtw8=; b=Dhx1QxsLF/sgmgDrv/8+usHu8Ymdfdw7twIdVerHK9UHRYfml9klBe6FxXxgGfIvfE 5y6fNWdtyQeg4P4JKvLoniZ0QjSoLMuc/UwcV4lFahbg2RbwC3YiwJTqfLNOGKxR3FlM VcWmiBkHI6sltSWLtL7YFhk/XnPpzsd/onIygnhwnOz3AAq16nOX/brmrTpZanWa+bAR fA82bBpylPtrifkrub8q1jCfpjv1bzuoJBxc4luI5BByT81nsRqEIFH8n2uqq59yzfjw oBkKod4FSRP+akYVF0vYC9dek2x3XH1/lPkjjtWtsDhfHi1873eaMISJSeGnqtxhZqEc EcJQ== X-Gm-Message-State: AOAM533PVZDeJxozkeAzvb7KZ3acgvbj26CXJnXmFE8QLEjNHNYNGdv7 wNtjzcP2XoAVc8X1O7O5rXgjfJtswcNz3ulYxnnoc5myXu4k46w7s5Eh7r0tPcWU8O50W1GiTN/ 74Ze5BNmLOopvVFpWQ00jBy2z X-Received: by 2002:a5d:47c2:: with SMTP id o2mr10221395wrc.143.1644244415598; Mon, 07 Feb 2022 06:33:35 -0800 (PST) X-Google-Smtp-Source: ABdhPJxXPlrsc3WVU2WCDHC7xWrbyQ8MhMs0AxOT19FexSR5IVk1QQ4rP0mfzjK34/aqbM6LemoI8A== X-Received: by 2002:a5d:47c2:: with SMTP id o2mr10221378wrc.143.1644244415397; Mon, 07 Feb 2022 06:33:35 -0800 (PST) Received: from ?IPV6:2003:cb:c709:6300:a751:d742:1f76:8639? (p200300cbc7096300a751d7421f768639.dip0.t-ipconnect.de. [2003:cb:c709:6300:a751:d742:1f76:8639]) by smtp.gmail.com with ESMTPSA id u7sm2354316wrq.112.2022.02.07.06.33.34 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 07 Feb 2022 06:33:34 -0800 (PST) Message-ID: <6d4ab70e-b944-5f7d-e9a3-979ac66c70f7@redhat.com> Date: Mon, 7 Feb 2022 15:33:34 +0100 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.4.0 Subject: Re: [PATCH] mm/memory_hotplug: fix kfree() of bootmem memory Content-Language: en-US To: Miaohe Lin , akpm@linux-foundation.org Cc: isimatu.yasuaki@jp.fujitsu.com, toshi.kani@hp.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org References: <20220207135618.17231-1-linmiaohe@huawei.com> From: David Hildenbrand Organization: Red Hat In-Reply-To: <20220207135618.17231-1-linmiaohe@huawei.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 07.02.22 14:56, Miaohe Lin wrote: > We can't use kfree() to release the resource as it might come from bootmem. > Use release_mem_region() instead. How can this happen? release_mem_region() is called either from __add_memory() or from add_memory_driver_managed(), where we allocated the region via register_memory_resource(). Both functions shouldn't ever be called before the buddy is up an running. Do you have a backtrace of an actual instance of this issue? Or was this identified as possibly broken by code inspection? -- Thanks, David / dhildenb