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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id A8E48C43334 for ; Mon, 27 Jun 2022 15:06:20 +0000 (UTC) Received: from localhost ([::1]:60754 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1o5qJf-0000Ln-IN for qemu-devel@archiver.kernel.org; Mon, 27 Jun 2022 11:06:19 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:34334) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1o5qGu-0007Im-RP for qemu-devel@nongnu.org; Mon, 27 Jun 2022 11:03:28 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:30111) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1o5qGl-0007Os-Ht for qemu-devel@nongnu.org; Mon, 27 Jun 2022 11:03:26 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1656342194; h=from:from:reply-to: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=BHlmpqJ82lrZF9e38zoCLn8R2L/oVhg+YbZ5rgRfXTk=; b=AUSUUaFBQm/YV6fjxRCUI5lB1mJqkAJcay2uuipw39wEcOknUFXdxibt49ZRD+tu5Gk6Y6 YR9q6clbAjC+2GUxrG2bsk9lCPiqmYcWnVMnRzJrL0ImXz1np3Z1ypw3pfnecoT9mHo7vz DuKAFsaaK+/9CmkuOUoNTZYExaLTL6w= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-192-SzSdr6GSMT-ywQq2tu16iQ-1; Mon, 27 Jun 2022 11:03:12 -0400 X-MC-Unique: SzSdr6GSMT-ywQq2tu16iQ-1 Received: from smtp.corp.redhat.com (int-mx09.intmail.prod.int.rdu2.redhat.com [10.11.54.9]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 9E2E18032EA; Mon, 27 Jun 2022 15:03:12 +0000 (UTC) Received: from redhat.com (unknown [10.33.36.120]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 88709492CA5; Mon, 27 Jun 2022 15:03:11 +0000 (UTC) Date: Mon, 27 Jun 2022 16:03:09 +0100 From: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= To: Peter Xu Cc: "Dr. David Alan Gilbert (git)" , qemu-devel@nongnu.org, huangy81@chinatelecom.cn, quintela@redhat.com, leobras@redhat.com, jdenemar@redhat.com Subject: Re: [PULL 22/33] migration: remove the QEMUFileOps 'get_buffer' callback Message-ID: References: <20220622183917.155308-1-dgilbert@redhat.com> <20220622183917.155308-23-dgilbert@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/2.2.6 (2022-06-05) X-Scanned-By: MIMEDefang 2.85 on 10.11.54.9 Received-SPF: pass client-ip=170.10.133.124; envelope-from=berrange@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -21 X-Spam_score: -2.2 X-Spam_bar: -- X-Spam_report: (-2.2 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.082, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Wed, Jun 22, 2022 at 03:34:52PM -0400, Peter Xu wrote: > On Wed, Jun 22, 2022 at 07:39:06PM +0100, Dr. David Alan Gilbert (git) wrote: > > diff --git a/migration/qemu-file.c b/migration/qemu-file.c > > index 74f919de67..e206b05550 100644 > > --- a/migration/qemu-file.c > > +++ b/migration/qemu-file.c > > @@ -377,8 +377,22 @@ static ssize_t qemu_fill_buffer(QEMUFile *f) > > return 0; > > } > > > > - len = f->ops->get_buffer(f->ioc, f->buf + pending, f->total_transferred, > > - IO_BUF_SIZE - pending, &local_error); > > + do { > > + len = qio_channel_read(f->ioc, > > + (char *)f->buf + pending, > > + IO_BUF_SIZE - pending, > > + &local_error); > > + if (len == QIO_CHANNEL_ERR_BLOCK) { > > + if (qemu_in_coroutine()) { > > + qio_channel_yield(f->ioc, G_IO_IN); > > + } else { > > + qio_channel_wait(f->ioc, G_IO_IN); > > + } > > + } else if (len < 0) { > > + len = EIO; > > This should be -EIO. > > > + } > > + } while (len == QIO_CHANNEL_ERR_BLOCK); > > It's failing only with the new TLS test I added for postcopy somehow (at > least /x86_64/migration/postcopy/recovery/tls).. I also verified after the > change it'll work again. Assuming you can still reproduce the pre-existing flaw, can you capture a stack trace when it hangs. I'm wondering if it is a sign that the migration is not converging when using TLS under certain load conditions, because the test waits forever for converge. Also what scenario are you running in ? Bare metal or a VM, and what host arch ? Wondering if the machine is at all slow, or for example missing AES hardware acceleration or some such thing. With regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|