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 X-Spam-Level: X-Spam-Status: No, score=-1.0 required=3.0 tests=MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 02F14C2BA19 for ; Sat, 18 Apr 2020 23:20:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CC67C21927 for ; Sat, 18 Apr 2020 23:20:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725969AbgDRXUA convert rfc822-to-8bit (ORCPT ); Sat, 18 Apr 2020 19:20:00 -0400 Received: from mail.kernel.org ([198.145.29.99]:44254 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725804AbgDRXUA (ORCPT ); Sat, 18 Apr 2020 19:20:00 -0400 From: bugzilla-daemon@bugzilla.kernel.org To: kvm@vger.kernel.org Subject: [Bug 206579] KVM with passthrough generates "BUG: kernel NULL pointer dereference" and crashes Date: Sat, 18 Apr 2020 23:19:59 +0000 X-Bugzilla-Reason: None X-Bugzilla-Type: changed 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: normal X-Bugzilla-Who: anthonysanwo@googlemail.com X-Bugzilla-Status: NEW X-Bugzilla-Resolution: X-Bugzilla-Priority: P1 X-Bugzilla-Assigned-To: virtualization_kvm@kernel-bugs.osdl.org X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: Message-ID: In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8BIT X-Bugzilla-URL: https://bugzilla.kernel.org/ Auto-Submitted: auto-generated MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org https://bugzilla.kernel.org/show_bug.cgi?id=206579 --- Comment #60 from Anthony (anthonysanwo@googlemail.com) --- To add hiding cpu id hypervisor seems to also cause it to not work well. Windows also generally don't perform as well when hiding the hypervisor CPU id on Ryzen. Using top we see high activity in avic_vcpu_put.part.0 & avic_vcpu_load functions and near-zero to zero activity with svm_deliver_avic_intr function. Which suggests AVIC isn't working correctly if my sight understanding of svm_deliver_avic_intr function is correct. Haven't looked to in-depth but I would guess SVM/AVIC uses hypervisor cpuid as check? to apply its optimizations or something along those lines. -- You are receiving this mail because: You are watching the assignee of the bug.