From mboxrd@z Thu Jan 1 00:00:00 1970 From: bugzilla-daemon@bugzilla.kernel.org Subject: [Bug 88671] Radeon driver fails to reset hardware properly after kvm guest reboot Date: Mon, 02 Mar 2015 17:32:49 +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]:39661 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753894AbbCBRcw (ORCPT ); Mon, 2 Mar 2015 12:32:52 -0500 Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id BEA642021F for ; Mon, 2 Mar 2015 17:32:51 +0000 (UTC) Received: from bugzilla1.web.kernel.org (bugzilla1.web.kernel.org [172.20.200.51]) by mail.kernel.org (Postfix) with ESMTP id 8588B201CD for ; Mon, 2 Mar 2015 17:32:49 +0000 (UTC) In-Reply-To: Sender: kvm-owner@vger.kernel.org List-ID: https://bugzilla.kernel.org/show_bug.cgi?id=88671 --- Comment #7 from Alex Williamson --- (In reply to Tom Stellard from comment #6) > I've been playing with this a little more and it seems to be working > correctly, > but radeon dynamic power management (dpm) always fails to initialize on the > second guest boot. My questions are: > > 1. What methods are being used by kvm/qemu/libvirt to reset the GPU on guest > shutdown? Secondary PCI bus reset from the parent bridge. > 2. Is the problem only cuased by the fact that GPU reset is not implemented > correctly in the radeon driver of are there improvements that are needed in > kvm/qemu/libvirt in order to get this working? Without a device specific reset, we're doing to most thorough standard reset available to us. I've also tried to use some of the reset mechanisms implemented in the radeon FOSS driver but they offered no improvement over the bus reset. There seems to be some state retained in the device that is not cleared via bus reset. -- You are receiving this mail because: You are watching the assignee of the bug.