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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]:57892 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kKQDA-0000Or-Bt for qemu-devel@archiver.kernel.org; Mon, 21 Sep 2020 14:06:48 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:49344) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kKQ3Y-0001BC-4K for qemu-devel@nongnu.org; Mon, 21 Sep 2020 13:56:52 -0400 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:44888) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1kKQ3V-00023R-Qe for qemu-devel@nongnu.org; Mon, 21 Sep 2020 13:56:51 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1600711008; 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; 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auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=dgilbert@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Received-SPF: pass client-ip=63.128.21.124; envelope-from=dgilbert@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/09/21 01:44:53 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: -35 X-Spam_score: -3.6 X-Spam_bar: --- X-Spam_report: (-3.6 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-1.455, 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_H5=0.001, RCVD_IN_MSPIKE_WL=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: anthony.perard@citrix.com, sstabellini@kernel.org, qemu-devel@nongnu.org, Juan Quintela Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" * Dov Murik (dovmurik@linux.vnet.ibm.com) wrote: > > > On 21/09/2020 14:17, Dr. David Alan Gilbert wrote: > > * Dov Murik (dovmurik@linux.vnet.ibm.com) wrote: > > > When running the xen-save-devices-state QMP command, if the filename > > > already exists it will be truncated before dumping the devices' state > > > into it. > > > > > > Signed-off-by: Dov Murik > > > --- > > > > OK, that looks fine to me, so: > > > > Reviewed-by: Dr. David Alan Gilbert > > > > > > > > Note that I found the above issue while trying to debug > > > xen-load-devices-state which simply fails (prints "Configuration section > > > missing" to stderr) directly after xen-save-devices-state (in the same > > > VM). I wonder if I should file a bug report as-is or investigate some > > > more. Advice welcome. > > > > I don't try the xen-* commands normally; I've cc'ing in Stefano and > > Anthony. > > Thanks Dave. Just to be clear, I'm running this without Xen at all; but > these commands seem to work OK for dumping/restoring guest's devices > state (without RAM) -- if I modify the code to circumvent the mentioned > problem. Yeh, although you can't rely on them not doing something Xen in the future. There are a few other similar ways of doing what you want; eg. if your RAM is 'shared' then you can set the x-ignore-shared migration capability. Dave > Dov > > > > > Dave > > > > > > > > -Dov > > > > > > --- > > > migration/savevm.c | 3 ++- > > > 1 file changed, 2 insertions(+), 1 deletion(-) > > > > > > diff --git a/migration/savevm.c b/migration/savevm.c > > > index 304d98ff78..e1b26672cc 100644 > > > --- a/migration/savevm.c > > > +++ b/migration/savevm.c > > > @@ -2803,7 +2803,8 @@ void qmp_xen_save_devices_state(const char *filename, bool has_live, bool live, > > > vm_stop(RUN_STATE_SAVE_VM); > > > global_state_store_running(); > > > - ioc = qio_channel_file_new_path(filename, O_WRONLY | O_CREAT, 0660, errp); > > > + ioc = qio_channel_file_new_path(filename, O_WRONLY | O_CREAT | O_TRUNC, > > > + 0660, errp); > > > if (!ioc) { > > > goto the_end; > > > } > > > -- > > > 2.20.1 > > > > -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK