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=-7.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,NICE_REPLY_A,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 E58AFC433E0 for ; Tue, 16 Mar 2021 08:38:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B3C1365002 for ; Tue, 16 Mar 2021 08:38:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235169AbhCPIiJ (ORCPT ); Tue, 16 Mar 2021 04:38:09 -0400 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:39919 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235132AbhCPIh4 (ORCPT ); Tue, 16 Mar 2021 04:37:56 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1615883876; 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=ZwYMPkghKSi78ypCL3Mf4zRzURyEmjf0Bxk8gD4fMyM=; b=UP2wiaffZWgXvJU7ilXb621t3o8+I9UTs1io3bn23CdB1nhd0DjhRTmlQQVI72X4rtKPzf kulg4ZS02cQa7FQaqXWem8KcVtDM6DootFkxekG1vN+YAxKn1HY8CTL/RavP+TU0UkVUAi lSt+j/kS+6DwSgtuHNjW1G1VRR1bhVA= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-496-dlWIF-f9MoiE1W-ClZevFw-1; Tue, 16 Mar 2021 04:37:52 -0400 X-MC-Unique: dlWIF-f9MoiE1W-ClZevFw-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 3E845192D78C; Tue, 16 Mar 2021 08:37:51 +0000 (UTC) Received: from [10.36.114.203] (ovpn-114-203.ams2.redhat.com [10.36.114.203]) by smtp.corp.redhat.com (Postfix) with ESMTP id 0E63460C13; Tue, 16 Mar 2021 08:37:48 +0000 (UTC) Subject: Re: slow boot with 7fef431be9c9 ("mm/page_alloc: place pages to tail in __free_pages_core()") To: "Liang, Liang (Leo)" , Mike Rapoport Cc: "Deucher, Alexander" , "linux-kernel@vger.kernel.org" , amd-gfx list , Andrew Morton , "Huang, Ray" , "Koenig, Christian" , "Rafael J. Wysocki" , George Kennedy References: <0AE49D98-171A-42B9-9CFC-9193A9BD3346@redhat.com> <22437770-956e-f7b4-a8f6-3f1cc28c3ec2@redhat.com> From: David Hildenbrand Organization: Red Hat GmbH Message-ID: <0cc972a1-5b40-3017-33f8-b2610489ee18@redhat.com> Date: Tue, 16 Mar 2021 09:37:48 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.8.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 16.03.21 09:00, Liang, Liang (Leo) wrote: > [AMD Public Use] > > Hi Mike, > > Thanks for help. The patch works for me and boot time back to normal. So it's a fix, or just WA? Hi Leo, excluding up to 16 MiB of memory on every system just because that single platform is weird is not acceptable. I think we have to figure out a) why that memory is so special. This is weird. b) why the platform doesn't indicate it in a special way. Why is it ordinary system RAM but still *that* slow? c) how we can reliably identify such memory and exclude it. I'll have a peek at the memory layout of that machine from boot logs next to figure out if we can answer any of these questions. Just to verify: this does happen on multiple machines, not just a single one? (i.e., we're not dealing with faulty RAM) -- Thanks, David / dhildenb