From patchwork Sat Feb 23 16:05:29 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jan Kiszka X-Patchwork-Id: 2178531 Return-Path: X-Original-To: patchwork-kvm@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork1.kernel.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by patchwork1.kernel.org (Postfix) with ESMTP id 1BDA13FCF6 for ; Sat, 23 Feb 2013 16:05:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759227Ab3BWQFh (ORCPT ); Sat, 23 Feb 2013 11:05:37 -0500 Received: from mout.web.de ([212.227.15.3]:62824 "EHLO mout.web.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758763Ab3BWQFh (ORCPT ); Sat, 23 Feb 2013 11:05:37 -0500 Received: from mchn199C.mchp.siemens.de ([95.157.56.37]) by smtp.web.de (mrweb001) with ESMTPSA (Nemesis) id 0MeScR-1UUxBl38xD-00QEAg; Sat, 23 Feb 2013 17:05:31 +0100 Message-ID: <5128E8C9.1050000@web.de> Date: Sat, 23 Feb 2013 17:05:29 +0100 From: Jan Kiszka User-Agent: Mozilla/5.0 (X11; U; Linux i686 (x86_64); de; rv:1.8.1.12) Gecko/20080226 SUSE/2.0.0.12-1.1 Thunderbird/2.0.0.12 Mnenhy/0.7.5.666 MIME-Version: 1.0 To: Marcelo Tosatti , Gleb Natapov CC: kvm Subject: [PATCH] x86: kvmclock: Do not setup kvmclock vsyscall in the absence of that clock X-Enigmail-Version: 1.5 X-Provags-ID: V02:K0:CKPJdPDXiLjwMgLf3kHE8fyXuvbT0yRS6SJ3sV4VHJD MJEJZsxNG4viA7PPGg15a2+4KsADmItA9qo9BrxrYjIvgbcLOl EyuVpbAZrP/UN15wS82rFVWB4wuLqAgprk7aNDWZCWhB56TIqC G855BzxtJSUhfvWOMQeoF5XIgfRxgK4Cj6XTa6SrSz7RW6TtwF L8scR6CT7wYJMCmNA4c/w== Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Jan Kiszka This fixes boot lockups with "no-kvmclock", when the host is not exposing this particular feature (QEMU: -cpu ...,-kvmclock) or when the kvmclock initialization failed for whatever reason. Signed-off-by: Jan Kiszka Reviewed-by: Marcelo Tosatti --- Should go to 3.8 as well, I presume. arch/x86/kernel/kvmclock.c | 9 ++++++++- 1 files changed, 8 insertions(+), 1 deletions(-) diff --git a/arch/x86/kernel/kvmclock.c b/arch/x86/kernel/kvmclock.c index 5bedbdd..b730efa 100644 --- a/arch/x86/kernel/kvmclock.c +++ b/arch/x86/kernel/kvmclock.c @@ -160,8 +160,12 @@ int kvm_register_clock(char *txt) { int cpu = smp_processor_id(); int low, high, ret; - struct pvclock_vcpu_time_info *src = &hv_clock[cpu].pvti; + struct pvclock_vcpu_time_info *src; + + if (!hv_clock) + return 0; + src = &hv_clock[cpu].pvti; low = (int)__pa(src) | 1; high = ((u64)__pa(src) >> 32); ret = native_write_msr_safe(msr_kvm_system_time, low, high); @@ -276,6 +280,9 @@ int __init kvm_setup_vsyscall_timeinfo(void) struct pvclock_vcpu_time_info *vcpu_time; unsigned int size; + if (!hv_clock) + return 0; + size = PAGE_ALIGN(sizeof(struct pvclock_vsyscall_time_info)*NR_CPUS); preempt_disable();