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=-8.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=ham 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 8C035C7618F for ; Mon, 15 Jul 2019 09:40:35 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 5A3582081C for ; Mon, 15 Jul 2019 09:40:35 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5A3582081C Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:36338 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1hmxTG-0000A3-A0 for qemu-devel@archiver.kernel.org; Mon, 15 Jul 2019 05:40:34 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:54482) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1hmxSw-0007gV-9K for qemu-devel@nongnu.org; Mon, 15 Jul 2019 05:40:15 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1hmxSu-000184-Tm for qemu-devel@nongnu.org; Mon, 15 Jul 2019 05:40:14 -0400 Received: from mx1.redhat.com ([209.132.183.28]:50474) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1hmxSu-00017Y-KF for qemu-devel@nongnu.org; Mon, 15 Jul 2019 05:40:12 -0400 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id E3439308FC4D; Mon, 15 Jul 2019 09:40:11 +0000 (UTC) Received: from work-vm (ovpn-117-181.ams2.redhat.com [10.36.117.181]) by smtp.corp.redhat.com (Postfix) with ESMTPS id E2CEA5D9D2; Mon, 15 Jul 2019 09:40:10 +0000 (UTC) Date: Mon, 15 Jul 2019 10:40:07 +0100 From: "Dr. David Alan Gilbert" To: Ivan Ren Message-ID: <20190715094007.GD2689@work-vm> References: <1563115879-2715-1-git-send-email-ivanren@tencent.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1563115879-2715-1-git-send-email-ivanren@tencent.com> User-Agent: Mutt/1.12.0 (2019-05-25) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.43]); Mon, 15 Jul 2019 09:40:11 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 Subject: Re: [Qemu-devel] [PATCH] migration: always initial RAMBlock.bmap to 1 for new migration X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: qemu-devel@nongnu.org, quintela@redhat.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" * Ivan Ren (renyime@gmail.com) wrote: > Reproduce the problem: > migrate > migrate_cancel > migrate > > Error happen for memory migration Can we fix this by just reverting 03158519384 ? Dave > The reason as follows: > 1. qemu start, ram_list.dirty_memory[DIRTY_MEMORY_MIGRATION] all set to > 1 by a series of cpu_physical_memory_set_dirty_range > 2. migration start:ram_init_bitmaps > - memory_global_dirty_log_start: begin log diry > - memory_global_dirty_log_sync: sync dirty bitmap to > ram_list.dirty_memory[DIRTY_MEMORY_MIGRATION] > - migration_bitmap_sync_range: sync ram_list. > dirty_memory[DIRTY_MEMORY_MIGRATION] to RAMBlock.bmap > and ram_list.dirty_memory[DIRTY_MEMORY_MIGRATION] is set to zero > 3. migration data... > 4. migrate_cancel, will stop log dirty > 5. migration start:ram_init_bitmaps > - memory_global_dirty_log_start: begin log diry > - memory_global_dirty_log_sync: sync dirty bitmap to > ram_list.dirty_memory[DIRTY_MEMORY_MIGRATION] > - migration_bitmap_sync_range: sync ram_list. > dirty_memory[DIRTY_MEMORY_MIGRATION] to RAMBlock.bmap > and ram_list.dirty_memory[DIRTY_MEMORY_MIGRATION] is set to zero > > Here RAMBlock.bmap only have new logged dirty pages, don't contain > the whole guest pages. > > Signed-off-by: Ivan Ren > --- > migration/ram.c | 15 ++++++++------- > 1 file changed, 8 insertions(+), 7 deletions(-) > > diff --git a/migration/ram.c b/migration/ram.c > index 908517fc2b..bbebaee0c1 100644 > --- a/migration/ram.c > +++ b/migration/ram.c > @@ -3173,11 +3173,11 @@ static int ram_state_init(RAMState **rsp) > QSIMPLEQ_INIT(&(*rsp)->src_page_requests); > > /* > + * Count the total number of pages used by ram blocks not including any > + * gaps due to alignment or unplugs. > * This must match with the initial values of dirty bitmap. > - * Currently we initialize the dirty bitmap to all zeros so > - * here the total dirty page count is zero. > */ > - (*rsp)->migration_dirty_pages = 0; > + (*rsp)->migration_dirty_pages = ram_bytes_total() >> TARGET_PAGE_BITS; > ram_state_reset(*rsp); > > return 0; > @@ -3196,12 +3196,13 @@ static void ram_list_init_bitmaps(void) > * The initial dirty bitmap for migration must be set with all > * ones to make sure we'll migrate every guest RAM page to > * destination. > - * Here we didn't set RAMBlock.bmap simply because it is already > - * set in ram_list.dirty_memory[DIRTY_MEMORY_MIGRATION] in > - * ram_block_add, and that's where we'll sync the dirty bitmaps. > - * Here setting RAMBlock.bmap would be fine too but not necessary. > + * Here we set RAMBlock.bmap all to 1 because when rebegin a > + * new migration after a failed migration, ram_list. > + * dirty_memory[DIRTY_MEMORY_MIGRATION] don't include the whole > + * guest memory. > */ > block->bmap = bitmap_new(pages); > + bitmap_set(block->bmap, 0, pages); > if (migrate_postcopy_ram()) { > block->unsentmap = bitmap_new(pages); > bitmap_set(block->unsentmap, 0, pages); > -- > 2.17.2 (Apple Git-113) > -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK