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=-5.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=no 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 8B34EC43461 for ; Thu, 10 Sep 2020 12:03:55 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 043F22075E for ; Thu, 10 Sep 2020 12:03:54 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 043F22075E Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 27DCC900005; Thu, 10 Sep 2020 08:03:53 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 207D3900004; Thu, 10 Sep 2020 08:03:53 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 0F65D900005; Thu, 10 Sep 2020 08:03:53 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0148.hostedemail.com [216.40.44.148]) by kanga.kvack.org (Postfix) with ESMTP id E8E89900004 for ; Thu, 10 Sep 2020 08:03:52 -0400 (EDT) Received: from smtpin22.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id 9ECC1362C for ; Thu, 10 Sep 2020 12:03:52 +0000 (UTC) X-FDA: 77247017904.22.heart02_380e192270e5 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin22.hostedemail.com (Postfix) with ESMTP id 70D1C18038E67 for ; Thu, 10 Sep 2020 12:03:52 +0000 (UTC) X-HE-Tag: heart02_380e192270e5 X-Filterd-Recvd-Size: 3980 Received: from mx2.suse.de (mx2.suse.de [195.135.220.15]) by imf28.hostedemail.com (Postfix) with ESMTP for ; Thu, 10 Sep 2020 12:03:51 +0000 (UTC) X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 66909AD52; Thu, 10 Sep 2020 12:04:06 +0000 (UTC) Date: Thu, 10 Sep 2020 14:03:48 +0200 From: Oscar Salvador To: Laurent Dufour Cc: Michal Hocko , akpm@linux-foundation.org, David Hildenbrand , rafael@kernel.org, nathanl@linux.ibm.com, cheloha@linux.ibm.com, stable@vger.kernel.org, Greg Kroah-Hartman , linux-mm@kvack.org, LKML Subject: Re: [PATCH] mm: don't rely on system state to detect hot-plug operations Message-ID: <20200910120343.GA6635@linux> References: <20200909074011.GD7348@dhcp22.suse.cz> <9faac1ce-c02d-7dbc-f79a-4aaaa5a73d28@linux.ibm.com> <20200909090953.GE7348@dhcp22.suse.cz> <4cdb54be-1a92-4ba4-6fee-3b415f3468a9@linux.ibm.com> <20200909105914.GF7348@dhcp22.suse.cz> <74a62b00-235e-7deb-2814-f3b240fea25e@linux.ibm.com> <20200910072331.GB28354@dhcp22.suse.cz> <31cfdf35-618f-6f56-ef16-0d999682ad02@linux.ibm.com> <20200910111246.GE28354@dhcp22.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) X-Rspamd-Queue-Id: 70D1C18038E67 X-Spamd-Result: default: False [0.00 / 100.00] X-Rspamd-Server: rspam03 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Thu, Sep 10, 2020 at 01:35:32PM +0200, Laurent Dufour wrote: > That points has been raised by David, quoting him here: > > > IIRC, ACPI can hotadd memory while SCHEDULING, this patch would break that. > > > > Ccing Oscar, I think he mentioned recently that this is the case with ACPI. > > Oscar told that he need to investigate further on that. I think my reply got lost. We can see acpi hotplugs during SYSTEM_SCHEDULING: $QEMU -enable-kvm -machine pc -smp 4,sockets=4,cores=1,threads=1 -cpu host -monitor pty \ -m size=$MEM,slots=255,maxmem=4294967296k \ -numa node,nodeid=0,cpus=0-3,mem=512 -numa node,nodeid=1,mem=512 \ -object memory-backend-ram,id=memdimm0,size=134217728 -device pc-dimm,node=0,memdev=memdimm0,id=dimm0,slot=0 \ -object memory-backend-ram,id=memdimm1,size=134217728 -device pc-dimm,node=0,memdev=memdimm1,id=dimm1,slot=1 \ -object memory-backend-ram,id=memdimm2,size=134217728 -device pc-dimm,node=0,memdev=memdimm2,id=dimm2,slot=2 \ -object memory-backend-ram,id=memdimm3,size=134217728 -device pc-dimm,node=0,memdev=memdimm3,id=dimm3,slot=3 \ -object memory-backend-ram,id=memdimm4,size=134217728 -device pc-dimm,node=1,memdev=memdimm4,id=dimm4,slot=4 \ -object memory-backend-ram,id=memdimm5,size=134217728 -device pc-dimm,node=1,memdev=memdimm5,id=dimm5,slot=5 \ -object memory-backend-ram,id=memdimm6,size=134217728 -device pc-dimm,node=1,memdev=memdimm6,id=dimm6,slot=6 \ kernel: [ 0.753643] __add_memory: nid: 0 start: 0100000000 - 0108000000 (size: 134217728) kernel: [ 0.756950] register_mem_sect_under_node: system_state= 1 kernel: [ 0.760811] register_mem_sect_under_node+0x4f/0x230 kernel: [ 0.760811] walk_memory_blocks+0x80/0xc0 kernel: [ 0.760811] link_mem_sections+0x32/0x40 kernel: [ 0.760811] add_memory_resource+0x148/0x250 kernel: [ 0.760811] __add_memory+0x5b/0x90 kernel: [ 0.760811] acpi_memory_device_add+0x130/0x300 kernel: [ 0.760811] acpi_bus_attach+0x13c/0x1c0 kernel: [ 0.760811] acpi_bus_attach+0x60/0x1c0 kernel: [ 0.760811] acpi_bus_scan+0x33/0x70 kernel: [ 0.760811] acpi_scan_init+0xea/0x21b kernel: [ 0.760811] acpi_init+0x2f1/0x33c kernel: [ 0.760811] do_one_initcall+0x46/0x1f4 -- Oscar Salvador SUSE L3