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=-11.1 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,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 92601C433E2 for ; Fri, 11 Sep 2020 17:36:35 +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 226FC221E7 for ; Fri, 11 Sep 2020 17:36:35 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="Se3gMluq" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 226FC221E7 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]:34592 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kGmyQ-0004Gg-3V for qemu-devel@archiver.kernel.org; Fri, 11 Sep 2020 13:36:34 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:46416) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kGmxS-0002Zq-2w for qemu-devel@nongnu.org; Fri, 11 Sep 2020 13:35:34 -0400 Received: from us-smtp-1.mimecast.com ([207.211.31.81]:55889 helo=us-smtp-delivery-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1kGmxQ-0001gn-AO for qemu-devel@nongnu.org; Fri, 11 Sep 2020 13:35:33 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1599845731; 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: in-reply-to:in-reply-to:references:references; bh=fUQDJVGFEjiJJ/u2KB+BqhYg/Ze7AzOAVewXjT9Stgg=; b=Se3gMluq0z/tcEu11bwqGji3da46zxshobo8jh14d1Yi8Uj8PJ98fjOaSzC8CRFxvQ1fZZ H9j9Ofl5h4NLVS24JeqIu87MTP2rjxKKD+aJAOEhOBUG5Ovv9lbD4tVzd6A/Nn08L8ADAf JRFAlgoL9hYqfZQXGOKzoJg1DslQTNg= 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-297-_pNtptcQPweWPJpy3ed4xA-1; Fri, 11 Sep 2020 13:35:30 -0400 X-MC-Unique: _pNtptcQPweWPJpy3ed4xA-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id AD1F08010C7; Fri, 11 Sep 2020 17:35:28 +0000 (UTC) Received: from work-vm (ovpn-113-52.ams2.redhat.com [10.36.113.52]) by smtp.corp.redhat.com (Postfix) with ESMTPS id DC39310013D7; Fri, 11 Sep 2020 17:35:14 +0000 (UTC) Date: Fri, 11 Sep 2020 18:35:12 +0100 From: "Dr. David Alan Gilbert" To: Steve Sistare Subject: Re: [PATCH V1 09/32] savevm: prevent cprsave if memory is volatile Message-ID: <20200911173512.GO3310@work-vm> References: <1596122076-341293-1-git-send-email-steven.sistare@oracle.com> <1596122076-341293-10-git-send-email-steven.sistare@oracle.com> MIME-Version: 1.0 In-Reply-To: <1596122076-341293-10-git-send-email-steven.sistare@oracle.com> User-Agent: Mutt/1.14.6 (2020-07-11) X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=dgilbert@redhat.com X-Mimecast-Spam-Score: 0.002 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Received-SPF: pass client-ip=207.211.31.81; envelope-from=dgilbert@redhat.com; helo=us-smtp-delivery-1.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/09/11 00:33:53 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, 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: "Daniel P. Berrange" , "Michael S. Tsirkin" , Alex =?iso-8859-1?Q?Benn=E9e?= , Juan Quintela , qemu-devel@nongnu.org, Markus Armbruster , Alex Williamson , Stefan Hajnoczi , =?iso-8859-1?Q?Marc-Andr=E9?= Lureau , Paolo Bonzini , Philippe =?iso-8859-1?Q?Mathieu-Daud=E9?= Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" * Steve Sistare (steven.sistare@oracle.com) wrote: > cprsave and cprload require that guest ram be backed by an externally > visible shared file. Check that in cprsave. > > Signed-off-by: Steve Sistare > --- > exec.c | 32 ++++++++++++++++++++++++++++++++ > include/exec/memory.h | 2 ++ > migration/savevm.c | 4 ++++ > 3 files changed, 38 insertions(+) > > diff --git a/exec.c b/exec.c > index 6f381f9..02160e0 100644 > --- a/exec.c > +++ b/exec.c > @@ -2726,6 +2726,38 @@ ram_addr_t qemu_ram_addr_from_host(void *ptr) > return block->offset + offset; > } > > +/* > + * Return true if any memory regions are writable and not backed by shared > + * memory. Exclude x86 option rom shadow "pc.rom" by name, even though it is > + * writable. Tell me about 'pc.rom' - this is a very odd hack. Again note the trick done by the existing migration capability x-ignore-shared ; it doesn't special case, it just doesn't migrate the 'shared' blocks. Dave > + */ > +bool qemu_ram_volatile(Error **errp) > +{ > + RAMBlock *block; > + MemoryRegion *mr; > + bool ret = false; > + > + rcu_read_lock(); > + QLIST_FOREACH_RCU(block, &ram_list.blocks, next) { > + mr = block->mr; > + if (mr && > + memory_region_is_ram(mr) && > + !memory_region_is_ram_device(mr) && > + !memory_region_is_rom(mr) && > + (!mr->name || strcmp(mr->name, "pc.rom")) && > + (block->fd == -1 || !qemu_ram_is_shared(block))) { > + > + error_setg(errp, "Memory region %s is volatile", > + memory_region_name(mr)); > + ret = true; > + break; > + } > + } > + > + rcu_read_unlock(); > + return ret; > +} > + > /* Generate a debug exception if a watchpoint has been hit. */ > void cpu_check_watchpoint(CPUState *cpu, vaddr addr, vaddr len, > MemTxAttrs attrs, int flags, uintptr_t ra) > diff --git a/include/exec/memory.h b/include/exec/memory.h > index 307e527..6aafbb0 100644 > --- a/include/exec/memory.h > +++ b/include/exec/memory.h > @@ -2519,6 +2519,8 @@ bool ram_block_discard_is_disabled(void); > */ > bool ram_block_discard_is_required(void); > > +bool qemu_ram_volatile(Error **errp); > + > #endif > > #endif > diff --git a/migration/savevm.c b/migration/savevm.c > index 1509173..f101039 100644 > --- a/migration/savevm.c > +++ b/migration/savevm.c > @@ -2713,6 +2713,10 @@ void save_cpr_snapshot(const char *file, const char *mode, Error **errp) > return; > } > > + if (op == VMS_REBOOT && qemu_ram_volatile(errp)) { > + return; > + } > + > f = qf_file_open(file, O_CREAT | O_WRONLY | O_TRUNC, 0600, errp); > if (!f) { > return; > -- > 1.8.3.1 > -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK