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Date: Mon, 13 Jul 2026 14:48:38 +0200
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Subject: Re: [PATCH qemu-server v2 1/3] cpu config: disable vmx-mbec flag for
 machine versions < 11.0
To: Friedrich Weber <f.weber@proxmox.com>, pve-devel@lists.proxmox.com
References: <20260713124025.121154-1-f.ebner@proxmox.com>
 <20260713124025.121154-2-f.ebner@proxmox.com>
 <bf9c73f2-224e-4821-b8d9-a5ab44a00f64@proxmox.com>
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From: Fiona Ebner <f.ebner@proxmox.com>
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Am 13.07.26 um 2:46 PM schrieb Friedrich Weber:
> On 13/07/2026 14:40, Fiona Ebner wrote:
>> As reported in the community forum [0] and enterprise support, Windows
>> with MBEC and VBS can have issues on certain Intel CPUs, leading to
>> guest freezes and 100% CPU usage. Note that the vmx-mbec flag will
>> automatically be enabled if both QEMU (since 11.0) and the kernel
>> (since 7.0.0-3-pve) support it, but this is incorrect from a machine
>> version perspective, since the flag was enabled before. While there
> 
> Should this be "since the flag *not* enabled before"?

Yes, good catch! Maybe even "the feature was not available before",
since the flag did not even exist yet.