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 230A494895 for ; Fri, 13 Jan 2023 11:10:02 +0100 (CET) Received: from firstgate.proxmox.com (localhost [127.0.0.1]) by firstgate.proxmox.com (Proxmox) with ESMTP id EECE73E05 for ; Fri, 13 Jan 2023 11:09:31 +0100 (CET) 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)) (No client certificate requested) by firstgate.proxmox.com (Proxmox) with ESMTPS for ; Fri, 13 Jan 2023 11:09:30 +0100 (CET) Received: from proxmox-new.maurer-it.com (localhost.localdomain [127.0.0.1]) by proxmox-new.maurer-it.com (Proxmox) with ESMTP id 7F8C8447E7 for ; Fri, 13 Jan 2023 11:09:30 +0100 (CET) Date: Fri, 13 Jan 2023 11:09:29 +0100 From: Wolfgang Bumiller To: Markus Frank Cc: pve-devel@lists.proxmox.com Message-ID: <20230113100929.ug2oivbml5tuizst@fwblub> References: <20221125140857.121622-1-m.frank@proxmox.com> <20221125140857.121622-5-m.frank@proxmox.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20221125140857.121622-5-m.frank@proxmox.com> X-SPAM-LEVEL: Spam detection results: 0 AWL 0.211 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 docs v4 4/5] added vIOMMU documentation 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: Fri, 13 Jan 2023 10:10:02 -0000 On Fri, Nov 25, 2022 at 03:08:56PM +0100, Markus Frank wrote: > Signed-off-by: Markus Frank > --- > qm-pci-passthrough.adoc | 25 +++++++++++++++++++++++++ > 1 file changed, 25 insertions(+) > > diff --git a/qm-pci-passthrough.adoc b/qm-pci-passthrough.adoc > index fa6ba35..7ed4d49 100644 > --- a/qm-pci-passthrough.adoc > +++ b/qm-pci-passthrough.adoc > @@ -389,6 +389,31 @@ Example configuration with an `Intel GVT-g vGPU` (`Intel Skylake 6700k`): > With this set, {pve} automatically creates such a device on VM start, and > cleans it up again when the VM stops. > > +[[qm_pci_viommu]] > +vIOMMU > +~~~~~~ > + > +vIOMMU enables the option to passthrough pci devices to Level-2 VMs > +in Level-1 VMs via Nested Virtualisation. > + > +Host-Requirement: Set `intel_iommu=on` or `amd_iommu=on` depending on your > +CPU. And by "CPU" you mean kernel command line? ;-) > + > +VM-Requirement: For both Intel and AMD CPUs you will have to set > +`intel_iommu=on` as a Linux boot parameter in the vIOMMU-enabled-VM, because > +Qemu implements the Intel variant. ^ As mentioned, there does appear to be an amd_iommu device in the qemu code, so would the amd variant work? In my reply to the code patch I mentioned checking the host arch. But if you say we can use intel_iommu on AMD as well, I'd say, if both work, give the user a choice, otherwise we can of course just stick to the one that works ;-)