From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from firstgate.proxmox.com (firstgate.proxmox.com [212.224.123.68]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by lists.proxmox.com (Postfix) with ESMTPS id BC9BE6D9FA for ; Wed, 18 Aug 2021 08:54:57 +0200 (CEST) Received: from firstgate.proxmox.com (localhost [127.0.0.1]) by firstgate.proxmox.com (Proxmox) with ESMTP id 9634287DC for ; Wed, 18 Aug 2021 08:54:27 +0200 (CEST) Received: from proxmox-new.maurer-it.com (proxmox-new.maurer-it.com [94.136.29.106]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by firstgate.proxmox.com (Proxmox) with ESMTPS id 3167187A5 for ; Wed, 18 Aug 2021 08:54:23 +0200 (CEST) Received: from proxmox-new.maurer-it.com (localhost.localdomain [127.0.0.1]) by proxmox-new.maurer-it.com (Proxmox) with ESMTP id 029D843415; Wed, 18 Aug 2021 08:54:23 +0200 (CEST) Date: Wed, 18 Aug 2021 08:54:22 +0200 From: Wolfgang Bumiller To: Constantin Herold Cc: pve-devel@lists.proxmox.com Message-ID: <20210818065422.rynkx5eovz6alsay@olga.proxmox.com> References: <20210812181642.1818-1-proxmox8914@herold.me> <20210817132148.b5zjoct22ccm4ste@olga.proxmox.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-SPAM-LEVEL: Spam detection results: 0 AWL 0.631 Adjusted score from AWL reputation of From: address BAYES_00 -1.9 Bayes spam probability is 0 to 1% KAM_DMARC_STATUS 0.01 Test Rule for DKIM or SPF Failure with Strict Alignment SPF_HELO_NONE 0.001 SPF: HELO does not publish an SPF Record SPF_PASS -0.001 SPF: sender matches SPF record Subject: Re: [pve-devel] [PATCH qemu-server] fix #3581: pass size via argument for memory-backend-ram qmp call X-BeenThere: pve-devel@lists.proxmox.com X-Mailman-Version: 2.1.29 Precedence: list List-Id: Proxmox VE development discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 18 Aug 2021 06:54:57 -0000 On Tue, Aug 17, 2021 at 05:32:00PM +0200, Constantin Herold wrote: > Sure no problem. > > In that case the patch will probably break memory hotplug for any VM's > tagged to Qemu <=4.2 I think it's okay as it's just the command interface to the running qemu process. * pve6 has qemu 5.2 (supports both variants) * pve7 has qemu 6.0 (supports only the new one) For clusters we recommend migrating running machines to different nodes when upgrading, which means they'll be running on pve6+qemu5.2 and then get migrated to pve7-qemu6, afterwards hotplug should be working once this patch lands. For in-place major-upgrades with machines running this doesn't really *break* a running machine, just prevents hotplug until it was either stop-started or a live-snapshot&rollback is performed. If you want to go the extra mile, the running qemu version could be queried, but I don't think we need to insist on doing this, as it just adds code complexity for backward-compatibility across a major-version boundary.