From nobody Mon Feb 9 08:11:32 2026 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; dkim=fail; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=redhat.com Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1629818933624550.8333857628268; Tue, 24 Aug 2021 08:28:53 -0700 (PDT) Received: from localhost ([::1]:58580 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1mIYM8-0004F2-My for importer@patchew.org; Tue, 24 Aug 2021 11:28:52 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:41078) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mIYKq-00022h-GA for qemu-devel@nongnu.org; Tue, 24 Aug 2021 11:27:32 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:57151) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mIYKo-0006ib-OW for qemu-devel@nongnu.org; Tue, 24 Aug 2021 11:27:32 -0400 Received: from mail-qv1-f69.google.com (mail-qv1-f69.google.com [209.85.219.69]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-137-nKy1tGyMMKe4pbneJdmaLA-1; Tue, 24 Aug 2021 11:27:28 -0400 Received: by mail-qv1-f69.google.com with SMTP id b8-20020a0562141148b02902f1474ce8b7so15084001qvt.20 for ; Tue, 24 Aug 2021 08:27:28 -0700 (PDT) Received: from t490s.phub.net.cable.rogers.com ([2607:fea8:56a3:500::d413]) by smtp.gmail.com with ESMTPSA id j127sm10939754qkf.20.2021.08.24.08.27.26 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 24 Aug 2021 08:27:27 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1629818849; 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=05wrd8rIW6nKro+F8yobZZdRrJtDZVauslriY61c9Ag=; b=bBMzZV36TkyojbRdNbylyPEVOzFSsF5UFdjV+yJzQFdoJHs9j5XWnT72h1wDHVUixZMAej Juy1G2kjVqlHnHuEPG6e6peo+o9PDRZpeR5GmSeWhQFEd5b62nQFc0nx8Vk0QDHZ4aJEl3 Rx7iU1I9mrqAEbhcj0ez8txYXOXwu9A= X-MC-Unique: nKy1tGyMMKe4pbneJdmaLA-1 X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=05wrd8rIW6nKro+F8yobZZdRrJtDZVauslriY61c9Ag=; b=fotJqoxXEYgKU70e0N6wDoupIMuLivO5OoGvJBpzhqYQhi17o0JwUrfeTb+tZQwv8H D9jmhUiUUOKZ/7ke4ixCi2uqjb7JRHphBJt1PLlgaemcHUybVE2aUsE62S9UyUcejcbK 4ocvB2rAsefPTNvo5w8G+25FbMrdp81M00eDOIXFbDjOK7F1nmrTCzAlCRCUlyknWqQf 9Vl3dvAnf6TVJCZRIgrBeM0udlgPggMWvF5tQIzxYvxJR80XaRDLc9Rwr/8hvxSnG5vm Ewy9EsYzbdYpo/3l2BjQa8RHkrW7LbgEUf1oWKBhwvBbHx51YsJuotADrUvTRGLCHdmL e9iQ== X-Gm-Message-State: AOAM531cOsIYkDO4zyHl/YkknlENoKyV2UHgelBdoHZdgpaIDqUDVls4 yKf/4CILcXln1pVBqhyaF0Lkc8WYVTbKLLzWsKOpV1Oc96ESzwPlGsTqs7vRyQg+Puz23f01A0z /Vha1XMdfKnwvWESo1KXa6EgRCoq6qTzvBUYSUssjQ1reGYyqM8Egx/id5eIVk+LO X-Received: by 2002:a0c:aac3:: with SMTP id g3mr22418149qvb.14.1629818847985; Tue, 24 Aug 2021 08:27:27 -0700 (PDT) X-Google-Smtp-Source: ABdhPJyc008iARgjQeS7QDBo0t7U0ZYYqu7hQjvwpfxLauOWl14/X2xYU12K9WVBWYVBQX2Up7C15g== X-Received: by 2002:a0c:aac3:: with SMTP id g3mr22418112qvb.14.1629818847684; Tue, 24 Aug 2021 08:27:27 -0700 (PDT) From: Peter Xu To: qemu-devel@nongnu.org Subject: [PATCH 2/2] dump-guest-memory: Block live migration Date: Tue, 24 Aug 2021 11:27:21 -0400 Message-Id: <20210824152721.79747-3-peterx@redhat.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210824152721.79747-1-peterx@redhat.com> References: <20210824152721.79747-1-peterx@redhat.com> MIME-Version: 1.0 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=peterx@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Transfer-Encoding: quoted-printable Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=216.205.24.124; envelope-from=peterx@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -34 X-Spam_score: -3.5 X-Spam_bar: --- X-Spam_report: (-3.5 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.747, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H2=-0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action 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: Andrew Jones , Juan Quintela , "Dr . David Alan Gilbert" , peterx@redhat.com, Leonardo Bras Soares Passos , =?UTF-8?q?Marc-Andr=C3=A9=20Lureau?= Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail-DKIM: fail (Header signature does not verify) X-ZM-MESSAGEID: 1629818934752100001 Content-Type: text/plain; charset="utf-8" Both dump-guest-memory and live migration caches vm state at the beginning. Either of them entering the other one will cause race on the vm state, and = even more severe on that (please refer to the crash report in the bug link). Let's block live migration in dump-guest-memory, and that'll also block dump-guest-memory if it detected that we're during a live migration. Side note: migrate_del_blocker() can be called even if the blocker is not inserted yet, so it's safe to unconditionally delete that blocker in dump_cleanup (g_slist_remove allows no-entry-found case). Suggested-by: Dr. David Alan Gilbert Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=3D1996609 Signed-off-by: Peter Xu --- dump/dump.c | 20 +++++++++++++++----- include/sysemu/dump.h | 1 + 2 files changed, 16 insertions(+), 5 deletions(-) diff --git a/dump/dump.c b/dump/dump.c index ab625909f3..7996d7a6c5 100644 --- a/dump/dump.c +++ b/dump/dump.c @@ -29,6 +29,7 @@ #include "qemu/error-report.h" #include "qemu/main-loop.h" #include "hw/misc/vmcoreinfo.h" +#include "migration/blocker.h" =20 #ifdef TARGET_X86_64 #include "win_dump.h" @@ -101,6 +102,7 @@ static int dump_cleanup(DumpState *s) qemu_mutex_unlock_iothread(); } } + migrate_del_blocker(s->dump_migration_blocker); =20 return 0; } @@ -1857,6 +1859,19 @@ static void dump_init(DumpState *s, int fd, bool has= _format, } } =20 + if (!s->dump_migration_blocker) { + error_setg(&s->dump_migration_blocker, + "Live migration disabled: dump-guest-memory in progress= "); + } + + /* + * Allows even for -only-migratable, but forbid migration during the + * process of dump guest memory. + */ + if (migrate_add_blocker_internal(s->dump_migration_blocker, errp)) { + goto cleanup; + } + return; =20 cleanup: @@ -1927,11 +1942,6 @@ void qmp_dump_guest_memory(bool paging, const char *= file, Error *local_err =3D NULL; bool detach_p =3D false; =20 - if (runstate_check(RUN_STATE_INMIGRATE)) { - error_setg(errp, "Dump not allowed during incoming migration."); - return; - } - /* if there is a dump in background, we should wait until the dump * finished */ if (dump_in_progress()) { diff --git a/include/sysemu/dump.h b/include/sysemu/dump.h index 250143cb5a..7b619c2a43 100644 --- a/include/sysemu/dump.h +++ b/include/sysemu/dump.h @@ -195,6 +195,7 @@ typedef struct DumpState { * finished. */ uint8_t *guest_note; /* ELF note content */ size_t guest_note_size; + Error *dump_migration_blocker; /* Blocker for live migration */ } DumpState; =20 uint16_t cpu_to_dump16(DumpState *s, uint16_t val); --=20 2.31.1