From mboxrd@z Thu Jan 1 00:00:00 1970 From: bugzilla-daemon@bugzilla.kernel.org Subject: [Bug 107561] 4.2 breaks PCI passthrough in QEMU/KVM Date: Fri, 11 Dec 2015 22:01:21 +0000 Message-ID: References: Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit To: kvm@vger.kernel.org Return-path: Received: from mail.kernel.org ([198.145.29.136]:60294 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751640AbbLKWB0 (ORCPT ); Fri, 11 Dec 2015 17:01:26 -0500 Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id A99A62054A for ; Fri, 11 Dec 2015 22:01:23 +0000 (UTC) Received: from bugzilla2.web.kernel.org (bugzilla2.web.kernel.org [172.20.200.52]) by mail.kernel.org (Postfix) with ESMTP id 930B420562 for ; Fri, 11 Dec 2015 22:01:22 +0000 (UTC) In-Reply-To: Sender: kvm-owner@vger.kernel.org List-ID: https://bugzilla.kernel.org/show_bug.cgi?id=107561 --- Comment #13 from schefister@gmail.com --- Sorry for the delay. I couldn't check sooner. Unfortunately the guest doesn't start with the patch applied. Nothing displayed (no sync signal from passthrough card). Host dmesg doesn't show any errors. Usually, even with slow guest I get the following on host dmesg when starting VM: ... VFIO - User Level meta-driver version: 0.3 kernel: vgaarb: device changed decodes: PCI:0000:01:00.0,olddecodes=io+mem,decodes=io+mem:owns=io+mem kernel: vfio_ecap_init: 0000:01:00.0 hiding ecap 0x1e@0x258 kernel: vfio_ecap_init: 0000:01:00.0 hiding ecap 0x19@0x900 kernel: pmd_set_huge: Cannot satisfy [mem 0xe0000000-0xe0200000] with a huge-page mapping due to MTRR override. - than some USB resets for keyboard passthrough - kernel: kvm: zapping shadow pages for mmio generation wraparound ...and so on, the guest screen displays UEFI startup by now With the patch applied it simly stops at the pmd_set_huge line, and nothing further, no usb, no guest start, no error messages. I also did follow up on the other tests. Disabling host mtrrs one-by-one did not yield any results. Guest is still slow even if disabling all the hosts mtrrs. Tried nukeing kvm_mtrr_get_guest_memory_type as requested and started a live distro. Guest did boot, but did not have a /proc/mtrr file. (Graphics scrolling was slow, I guess on account of lack of cacheing, but otherwise guest was speedy as normal) I saved some info from the guest, like dmesg, lspci -vvv, and some sysfs files. You can find them in the same share as before. https://drive.google.com/folderview?id=0B8ebX_WjVHnGNlN4eTEzU2xtMEk&usp=sharing -- You are receiving this mail because: You are watching the assignee of the bug.