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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED autolearn=ham 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 18E03C070C3 for ; Wed, 12 Sep 2018 19:23:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D1F6220880 for ; Wed, 12 Sep 2018 19:23:07 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D1F6220880 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=zytor.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728336AbeIMA3C (ORCPT ); Wed, 12 Sep 2018 20:29:02 -0400 Received: from terminus.zytor.com ([198.137.202.136]:51189 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728121AbeIMA3C (ORCPT ); Wed, 12 Sep 2018 20:29:02 -0400 Received: from terminus.zytor.com (localhost [127.0.0.1]) by terminus.zytor.com (8.15.2/8.15.2) with ESMTPS id w8CJMj2C2744437 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO); Wed, 12 Sep 2018 12:22:45 -0700 Received: (from tipbot@localhost) by terminus.zytor.com (8.15.2/8.15.2/Submit) id w8CJMi8t2744434; Wed, 12 Sep 2018 12:22:44 -0700 Date: Wed, 12 Sep 2018 12:22:44 -0700 X-Authentication-Warning: terminus.zytor.com: tipbot set sender to tipbot@zytor.com using -f From: tip-bot for Juergen Gross Message-ID: Cc: torvalds@linux-foundation.org, hpa@zytor.com, tglx@linutronix.de, jgross@suse.com, peterz@infradead.org, mingo@kernel.org, linux-kernel@vger.kernel.org Reply-To: hpa@zytor.com, torvalds@linux-foundation.org, tglx@linutronix.de, jgross@suse.com, linux-kernel@vger.kernel.org, mingo@kernel.org, peterz@infradead.org In-Reply-To: <20180912174122.24282-1-jgross@suse.com> References: <20180912174122.24282-1-jgross@suse.com> To: linux-tip-commits@vger.kernel.org Subject: [tip:x86/urgent] x86/xen: Disable CPU0 hotplug for Xen PV Git-Commit-ID: 999696752db1099aba595aac4f8d881f8c7cf4e6 X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: 999696752db1099aba595aac4f8d881f8c7cf4e6 Gitweb: https://git.kernel.org/tip/999696752db1099aba595aac4f8d881f8c7cf4e6 Author: Juergen Gross AuthorDate: Wed, 12 Sep 2018 19:41:22 +0200 Committer: Ingo Molnar CommitDate: Wed, 12 Sep 2018 21:15:02 +0200 x86/xen: Disable CPU0 hotplug for Xen PV Xen PV guests don't allow CPU0 hotplug, so disable it. Signed-off-by: Juergen Gross Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: boris.ostrovsky@oracle.com Cc: xen-devel@lists.xenproject.org Link: http://lkml.kernel.org/r/20180912174122.24282-1-jgross@suse.com Signed-off-by: Ingo Molnar --- arch/x86/kernel/topology.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/arch/x86/kernel/topology.c b/arch/x86/kernel/topology.c index 12cbe2b88c0f..738bf42b0218 100644 --- a/arch/x86/kernel/topology.c +++ b/arch/x86/kernel/topology.c @@ -111,8 +111,10 @@ int arch_register_cpu(int num) /* * Currently CPU0 is only hotpluggable on Intel platforms. Other * vendors can add hotplug support later. + * Xen PV guests don't support CPU0 hotplug at all. */ - if (c->x86_vendor != X86_VENDOR_INTEL) + if (c->x86_vendor != X86_VENDOR_INTEL || + boot_cpu_has(X86_FEATURE_XENPV)) cpu0_hotpluggable = 0; /*