From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from firstgate.proxmox.com (firstgate.proxmox.com [IPv6:2a01:7e0:0:424::9]) by lore.proxmox.com (Postfix) with ESMTPS id 3254C1FF16B for ; Fri, 7 Nov 2025 13:13:12 +0100 (CET) Received: from firstgate.proxmox.com (localhost [127.0.0.1]) by firstgate.proxmox.com (Proxmox) with ESMTP id 14553FD31; Fri, 7 Nov 2025 13:13:53 +0100 (CET) Mime-Version: 1.0 Date: Fri, 07 Nov 2025 13:13:18 +0100 Message-Id: From: "Daniel Kral" To: "Fiona Ebner" , "Proxmox VE development discussion" , "Daniel Kral" X-Mailer: aerc 0.21.0-10-gf12c391cb5b4 References: <20251031122834.62482-1-f.ebner@proxmox.com> In-Reply-To: X-Bm-Milter-Handled: 55990f41-d878-4baa-be0a-ee34c49e34d2 X-Bm-Transport-Timestamp: 1762517578401 X-SPAM-LEVEL: Spam detection results: 0 AWL 0.016 Adjusted score from AWL reputation of From: address BAYES_00 -1.9 Bayes spam probability is 0 to 1% DMARC_MISSING 0.1 Missing DMARC policy KAM_DMARC_STATUS 0.01 Test Rule for DKIM or SPF Failure with Strict Alignment RCVD_IN_VALIDITY_CERTIFIED_BLOCKED 0.001 ADMINISTRATOR NOTICE: The query to Validity was blocked. See https://knowledge.validity.com/hc/en-us/articles/20961730681243 for more information. RCVD_IN_VALIDITY_RPBL_BLOCKED 0.001 ADMINISTRATOR NOTICE: The query to Validity was blocked. See https://knowledge.validity.com/hc/en-us/articles/20961730681243 for more information. RCVD_IN_VALIDITY_SAFE_BLOCKED 0.001 ADMINISTRATOR NOTICE: The query to Validity was blocked. See https://knowledge.validity.com/hc/en-us/articles/20961730681243 for more information. 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-SERIES qemu-server/manager 0/7] VM CPU flags: introduce vendor-agnostic 'nested-virt' CPU flag 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: , Reply-To: Proxmox VE development discussion Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: pve-devel-bounces@lists.proxmox.com Sender: "pve-devel" On Fri Nov 7, 2025 at 12:33 PM CET, Fiona Ebner wrote: > Am 06.11.25 um 6:14 PM schrieb Daniel Kral: >> - setting e.g. `-vmx` in a custom model and `+nested-virt` in the VM's >> cpu flags will result in: >> >> CPU flag 'nested-virt' resolved to 'vmx' >> warning: CPU flag/setting '+vmx' (manually set for VM) overwrites >> '-vmx' (set by custom CPU model) >> >> - but setting `-vmx` in the custom model and `-nested-virt` in the VM's >> cpu flags will result in only: >> >> CPU flag 'nested-virt' resolved to 'vmx' >> >> The same happens vice versa with `+vmx` in the custom model and >> `{+,-}nested-virt` in the VM's cpu flags. > > Well yes, this is part of the existing logic. Such a warning will only > get logged if settings on different configuration levels are > incompatible with each other. > > Note that the warning I added in the series is different and triggers > only when both nested-virt and smv/vmx are defined on the same level of > configuration. As pointed out off-list, this was more of a summary what I've tested and I think the messages are very good to have to see what 'nested-virt' resolves to in the end. > >> From what I can figure this should also work with live migration, >> because resolve_cpu_flags will be called at vm_start, right? > > My series does not change anything there. Between compatible models, it > will work. Between incompatible models, for example one with the flag, > one without or between different vendors, will not. > > But there is no early error and that is bad. We only pass along the > running CPU during migration when a custom model is used, but not > otherwise. I'll make sure to also pass it along if the nested-virt flag > is used in v2! And I'll mention the caveat in the description to make > sure people won't think this will magically make live migration between > different vendors with nesting work or something. Yeah that would be a good notice to have even though changing cpu vendors in a 'hotplug' fashion isn't usually what I'd think someone would expect, but you never know :). _______________________________________________ pve-devel mailing list pve-devel@lists.proxmox.com https://lists.proxmox.com/cgi-bin/mailman/listinfo/pve-devel