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 23B82EB64D8 for ; Wed, 14 Jun 2023 06:46:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241554AbjFNGqE (ORCPT ); Wed, 14 Jun 2023 02:46:04 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52282 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233721AbjFNGqD (ORCPT ); Wed, 14 Jun 2023 02:46:03 -0400 Received: from szxga08-in.huawei.com (szxga08-in.huawei.com [45.249.212.255]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 27B9F1A5; Tue, 13 Jun 2023 23:46:02 -0700 (PDT) Received: from dggpemm500014.china.huawei.com (unknown [172.30.72.57]) by szxga08-in.huawei.com (SkyGuard) with ESMTP id 4QgwmZ4blkz18MCF; Wed, 14 Jun 2023 14:41:02 +0800 (CST) Received: from [10.174.178.120] (10.174.178.120) by dggpemm500014.china.huawei.com (7.185.36.153) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.23; Wed, 14 Jun 2023 14:45:58 +0800 Message-ID: Date: Wed, 14 Jun 2023 14:45:58 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:102.0) Gecko/20100101 Thunderbird/102.10.1 CC: , , , , , , , , , , , Subject: Re: [PATCH stable 5.10 1/1] mm/memory_hotplug: extend offline_and_remove_memory() to handle more than one memory block Content-Language: en-US To: References: <20230614061900.3296725-1-mawupeng1@huawei.com> <20230614061900.3296725-2-mawupeng1@huawei.com> <2023061440-showing-happiest-937e@gregkh> From: mawupeng In-Reply-To: <2023061440-showing-happiest-937e@gregkh> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.174.178.120] X-ClientProxiedBy: dggems704-chm.china.huawei.com (10.3.19.181) To dggpemm500014.china.huawei.com (7.185.36.153) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org On 2023/6/14 14:35, Greg KH wrote: > On Wed, Jun 14, 2023 at 02:19:00PM +0800, Wupeng Ma wrote: >> From: David Hildenbrand >> >> virtio-mem soon wants to use offline_and_remove_memory() memory that >> exceeds a single Linux memory block (memory_block_size_bytes()). Let's >> remove that restriction. >> >> Let's remember the old state and try to restore that if anything goes >> wrong. While re-onlining can, in general, fail, it's highly unlikely to >> happen (usually only when a notifier fails to allocate memory, and these >> are rather rare). >> >> This will be used by virtio-mem to offline+remove memory ranges that are >> bigger than a single memory block - for example, with a device block >> size of 1 GiB (e.g., gigantic pages in the hypervisor) and a Linux memory >> block size of 128MB. >> >> While we could compress the state into 2 bit, using 8 bit is much >> easier. >> >> This handling is similar, but different to acpi_scan_try_to_offline(): >> >> a) We don't try to offline twice. I am not sure if this CONFIG_MEMCG >> optimization is still relevant - it should only apply to ZONE_NORMAL >> (where we have no guarantees). If relevant, we can always add it. >> >> b) acpi_scan_try_to_offline() simply onlines all memory in case >> something goes wrong. It doesn't restore previous online type. Let's do >> that, so we won't overwrite what e.g., user space configured. >> >> Reviewed-by: Wei Yang >> Cc: "Michael S. Tsirkin" >> Cc: Jason Wang >> Cc: Pankaj Gupta >> Cc: Michal Hocko >> Cc: Oscar Salvador >> Cc: Wei Yang >> Cc: Andrew Morton >> Signed-off-by: David Hildenbrand >> Link: https://lore.kernel.org/r/20201112133815.13332-28-david@redhat.com >> Signed-off-by: Michael S. Tsirkin >> Acked-by: Andrew Morton >> --- >> mm/memory_hotplug.c | 105 +++++++++++++++++++++++++++++++++++++------- >> 1 file changed, 89 insertions(+), 16 deletions(-) > > As you forwarded this patch on, you too need to sign-off on it. Thanks for reminding me. Signed-off-by: Ma Wupeng > > Also, what is the git id of the commit in Linus's tree? Sorry, here is the commit in Linus's tree. commit 8dc4bb58a146655eb057247d7c9d19e73928715b upstream. > > thanks, > > greg k-h