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 C9CD4EB64DA for ; Mon, 19 Jun 2023 06:20:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229956AbjFSGUw (ORCPT ); Mon, 19 Jun 2023 02:20:52 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41336 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229950AbjFSGUt (ORCPT ); Mon, 19 Jun 2023 02:20:49 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CE8FEB1; Sun, 18 Jun 2023 23:20:48 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 5D019610A6; Mon, 19 Jun 2023 06:20:48 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1099BC433C8; Mon, 19 Jun 2023 06:20:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1687155647; bh=RyhHvsArpvvLmzXBr8ZG4BEMJyn2f/6MIZNEdgiReLQ=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=RIz+gKiuBkUDhFOF+rHvjkUuRJWcTLFL6hb/qWGm3P1WcGcZo2lsKb31qMXSo8UHX XLlj2jIyynRfN/AMByM1FbRumqhWRnHLGC+GAHGkBDhYNeTS4mOm8M0oD5K7ygWzSi BcxZ68M2FSXO7oW6n/V+aqGkOQFU0W4UzNKTm89A= Date: Mon, 19 Jun 2023 08:20:43 +0200 From: Greg KH To: mawupeng Cc: akpm@linux-foundation.org, david@redhat.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, stable@vger.kernel.org, richard.weiyang@linux.alibaba.com, mst@redhat.com, jasowang@redhat.com, pankaj.gupta.linux@gmail.com, mhocko@kernel.org, osalvador@suse.de Subject: Re: [PATCH stable 5.10 1/1] mm/memory_hotplug: extend offline_and_remove_memory() to handle more than one memory block Message-ID: <2023061927-parsnip-gauging-86e9@gregkh> References: <20230614061900.3296725-1-mawupeng1@huawei.com> <20230614061900.3296725-2-mawupeng1@huawei.com> <2023061440-showing-happiest-937e@gregkh> 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 Wed, Jun 14, 2023 at 02:45:58PM +0800, mawupeng wrote: > > > 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. Please resend the change with both of these things fixed up, so I don't have to manually do it :) thanks, greg k-h