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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id C6AB0C7EE21 for ; Thu, 4 May 2023 11:50:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229818AbjEDLuC (ORCPT ); Thu, 4 May 2023 07:50:02 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60430 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229535AbjEDLuB (ORCPT ); Thu, 4 May 2023 07:50:01 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CAF121994 for ; Thu, 4 May 2023 04:49:59 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 6205B612BC for ; Thu, 4 May 2023 11:49:59 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPS id C5154C4339C for ; Thu, 4 May 2023 11:49:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1683200998; bh=T1lPGCb9cUcG0qL2ThryvV77gSg6Wd+sbgjjpzxS3PU=; h=From:To:Subject:Date:From; b=TMHlxPiVskv6GwO1cyB8EPmGtCwnCsDa6I0J0WVynVFHz9Rp2ycZG/vHsZEDt6ls0 sfCav/N0/pfVQWrbWGoe7xqpYZdNnKOGqlh1B8P2LiwADUKs079SQR8T+QIRHRTD6v pSBkBaAVY5MkZI0atlR0BsrYFdHgIzDJhR3LfZsGfYRwqAUvnwDrnl79fNM5aIr3Kn e1radAFtiSw4zpcqjRtQtIbyeLdfQwzgW7T9flyndAOkBh/R1AJfG7gZk6jGe3+8z3 Z1G62Lvc9Gu9TGB7E1SnBiKq5byM1x/u5sVH/1RKLc/Hj7y+8FD9RA8WEDqLjzxHuu N9W3wTy09fwKA== Received: by aws-us-west-2-korg-bugzilla-1.web.codeaurora.org (Postfix, from userid 48) id B1ACEC43144; Thu, 4 May 2023 11:49:58 +0000 (UTC) From: bugzilla-daemon@kernel.org To: kvm@vger.kernel.org Subject: [Bug 217400] New: Bugged RMRR prevents PCIe Passthrough of KVM VMs on certain platforms Date: Thu, 04 May 2023 11:49:58 +0000 X-Bugzilla-Reason: None X-Bugzilla-Type: new X-Bugzilla-Watch-Reason: AssignedTo virtualization_kvm@kernel-bugs.osdl.org X-Bugzilla-Product: Virtualization X-Bugzilla-Component: kvm X-Bugzilla-Version: unspecified X-Bugzilla-Keywords: X-Bugzilla-Severity: high X-Bugzilla-Who: bugtracker@fischbytes.de X-Bugzilla-Status: NEW X-Bugzilla-Resolution: X-Bugzilla-Priority: P3 X-Bugzilla-Assigned-To: virtualization_kvm@kernel-bugs.osdl.org X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: bug_id short_desc product version rep_platform op_sys bug_status bug_severity priority component assigned_to reporter cf_regression Message-ID: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: https://bugzilla.kernel.org/ Auto-Submitted: auto-generated MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org https://bugzilla.kernel.org/show_bug.cgi?id=3D217400 Bug ID: 217400 Summary: Bugged RMRR prevents PCIe Passthrough of KVM VMs on certain platforms Product: Virtualization Version: unspecified Hardware: Intel OS: Linux Status: NEW Severity: high Priority: P3 Component: kvm Assignee: virtualization_kvm@kernel-bugs.osdl.org Reporter: bugtracker@fischbytes.de Regression: No Certain vendors that are under the assumption that standards are for jerks = and Intel's specifications are a loose optional guideline have implemented RMRR= in such a way that every PCI device is marked as reserved and therefore cannot= be passed through to a virtual machine. This issue has been very well document= ed by some people that have a lot more experience than I do at the below linked resource. I was hoping that the upstream Linux kernel could implement the Relaxed RMRR option, enabled by a kernel parameter at boot time, on these bugged platforms as that would re-enable or rather enable a lot of broken servers for the first time ever to use PCIe Passthrough. I can verify the i= ssue exists on a HPE DL360e Gen8 with trying to passthrough a GPU to a KVM/QEMU machine. This bug is very much hardware specific, but seems to only exist on Linux systems as they try to honor the Intel specifications as much as possible, it was reported that other systems (e.g. VMWare ESXi) do not have this issue as they ignore RMRR out-of-the-box.=20 https://github.com/Aterfax/relax-intel-rmrr I can confirm the patched Proxmox-Kernel works fine on an HPE DL360e Gen8. = The same bug was also reported to the openSUSE maintainers, they suggested to report it here instead. https://bugzilla.opensuse.org/show_bug.cgi?id=3D1211069 --=20 You may reply to this email to add a comment. You are receiving this mail because: You are watching the assignee of the bug.=