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 CCCF0D6A228 for ; Thu, 14 Nov 2024 19:05:56 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1tBf9A-0000rF-07; Thu, 14 Nov 2024 14:04:52 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1tBf95-0000pW-5V for qemu-devel@nongnu.org; Thu, 14 Nov 2024 14:04:47 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1tBf91-0004rA-Cj for qemu-devel@nongnu.org; Thu, 14 Nov 2024 14:04:46 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1731611075; 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=9DGLeFnfYlfnL8X6Xp15IxmQ14tej1WYYffFTO/joeI=; b=ip/LIjOtuTY3A1U8gyClu8J57mO606QOEjwEJuT8xeD0hsm5tgKnbS05oqCvl34DHWV17Y 3xiLqhxxQHH3iewqW/RpYQyW0UpeGpdDEsSSkMe+d8IcYqB7vHzDlaORNpCD9z1d4BBG7K GpwVddOxKkYm4hVCIh9FW1vz9YTBhkI= Received: from mail-io1-f69.google.com (mail-io1-f69.google.com [209.85.166.69]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-164-UubDUDUpMmCq2ohCbNQNhA-1; Thu, 14 Nov 2024 14:04:34 -0500 X-MC-Unique: UubDUDUpMmCq2ohCbNQNhA-1 X-Mimecast-MFC-AGG-ID: UubDUDUpMmCq2ohCbNQNhA Received: by mail-io1-f69.google.com with SMTP id ca18e2360f4ac-83b6628a71fso92117339f.0 for ; Thu, 14 Nov 2024 11:04:34 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1731611073; x=1732215873; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=9DGLeFnfYlfnL8X6Xp15IxmQ14tej1WYYffFTO/joeI=; b=M+j4QuUnGLE/ZvxJSXHIo3EDScBlwz3lqqwzHHljHM9C0nULcTKiKAQXFYghVuR8d/ 3I+x/70S1HBxfim9IuX7bWb9RedsWs5Z4V9yDaMtZce7zQNr9fDhfRRYWcsmbDViyFLQ XWaCeijQuxUK6LSGXEfpzGpHCx3nRA4b2pNdmQCQWUv+BcIHxsxY+h5/Cv51bIz0dsSE VvstqoYtNO4rX9chn1MDgfqGXAYATsi6t6A/azUYfsJ5WJgb5R02dTLOgPQhTgYug598 LZ/8cAduMNs2vxfILHh+CgEsoTKun//SlKgZK+T8GysX1VkBQpyKJkHWALAYqyabGxhb PvSg== X-Gm-Message-State: AOJu0YwlH/+ZBIIJ6XqGg6XSsUrxuv/EZexU1FnHH/xltgEjrcwKQYmP bdUOFGtxR1T0cUx8lAr07kbQ/p9t3vkNnFJ1b2OpCYKuxA0Uvk+dWfMIhASCJPXF6ryGIrrlXVm 4e/WRVG/Qp/nIYlSgz6hc1fm0N9ISoN+PRNULkTjhcZ6WpaWjm3bT X-Received: by 2002:a92:c245:0:b0:3a7:4700:7c1 with SMTP id e9e14a558f8ab-3a7470009f9mr1990675ab.12.1731611072958; Thu, 14 Nov 2024 11:04:32 -0800 (PST) X-Google-Smtp-Source: AGHT+IF9ArCs1Ij7io/DxI6HbGyyj3xvf+q45RajmiNwA07LUDizcryF3L1dK1C8TCIZVGf8d5yfWw== X-Received: by 2002:a92:c245:0:b0:3a7:4700:7c1 with SMTP id e9e14a558f8ab-3a7470009f9mr1990365ab.12.1731611072603; Thu, 14 Nov 2024 11:04:32 -0800 (PST) Received: from x1n (pool-99-254-114-190.cpe.net.cable.rogers.com. [99.254.114.190]) by smtp.gmail.com with ESMTPSA id 8926c6da1cb9f-4e02fd14876sm390640173.100.2024.11.14.11.04.31 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 14 Nov 2024 11:04:31 -0800 (PST) Date: Thu, 14 Nov 2024 14:04:29 -0500 From: Peter Xu To: Steven Sistare Cc: qemu-devel@nongnu.org, Fabiano Rosas , David Hildenbrand , Marcel Apfelbaum , Eduardo Habkost , Philippe Mathieu-Daude , Paolo Bonzini , "Daniel P. Berrange" , Markus Armbruster Subject: Re: [PATCH V3 11/16] migration: cpr-transfer mode Message-ID: References: <1730468875-249970-1-git-send-email-steven.sistare@oracle.com> <1730468875-249970-12-git-send-email-steven.sistare@oracle.com> <51967cb2-05ec-485b-a639-8ff58d565604@oracle.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <51967cb2-05ec-485b-a639-8ff58d565604@oracle.com> Received-SPF: pass client-ip=170.10.133.124; envelope-from=peterx@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=-0.122, 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_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, RCVD_IN_VALIDITY_SAFE_BLOCKED=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: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On Thu, Nov 14, 2024 at 01:36:00PM -0500, Steven Sistare wrote: > On 11/13/2024 4:58 PM, Peter Xu wrote: > > On Fri, Nov 01, 2024 at 06:47:50AM -0700, Steve Sistare wrote: > > > Add the cpr-transfer migration mode. Usage: > > > qemu-system-$arch -machine anon-alloc=memfd ... > > > > > > start new QEMU with "-incoming -cpr-uri " > > > > > > Issue commands to old QEMU: > > > migrate_set_parameter mode cpr-transfer > > > migrate_set_parameter cpr-uri > > > migrate -d > > > > QMP command "migrate" already allows taking MigrationChannel lists, cpr can > > be the 2nd supported channel besides "main". > > > > I apologize on only noticing this until now.. I wished the incoming side > > can do the same already (which also takes 'MigrationChannel') if monitors > > init can be moved earlier, and if precreate worked out. If not, we should > > still consider doing that on source, because cpr-uri isn't usable on dest > > anyway.. so they need to be treated separately even now. > > > > Then after we make the monitor code run earlier in the future we could > > introduce that to incoming side too, obsoleting -cpr-uri there. > > I have already been shot down on precreate and monitors init, so we are > left with specifying a "cpr" channel on the outgoing side, and -cpr-uri > on the incoming side. That will confuse users, will require more implementation > and specification work than you perhaps realize to explain this to users, What is the specification work? Can you elaborate? > and only gets us halfway to your desired end point of specifying everything > using channels. I don't like that plan! > > If we ever get the ability to open the monitor early, then we can implement > a complete and clean solution using channels and declare the other options > obsolete. The sender side doesn't need to wait for destination side to be ready? Dest side isn't a reason to me on how we should make sender side work if they're totally separate anyway. Dest requires -cpr-uri because we don't yet have a choice. Is the only concern about code changes? I'm expecting this change is far less controversial comparing to many others in this series, even if I confess that may still contain some diff. They should hopefully be straightforward, unlike many of the changes elsewhere in the series. If you prefer not writting that patch, I am OK, and I can write one patch on top of your series after it lands if that is OK for you. I still want to have this there when release 10.0 if I didn't misunderstood anything, so I'll be able to remove cpr-uri directly in that patch too. -- Peter Xu