From patchwork Wed Jul 5 14:05:20 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Juergen Gross X-Patchwork-Id: 9826583 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 069DF60317 for ; Wed, 5 Jul 2017 14:07:53 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id E0873283C0 for ; Wed, 5 Jul 2017 14:07:52 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id D4A3428504; Wed, 5 Jul 2017 14:07:52 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.2 required=2.0 tests=BAYES_00, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 64291283C0 for ; Wed, 5 Jul 2017 14:07:52 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.84_2) (envelope-from ) id 1dSkw0-0000ZN-Rm; Wed, 05 Jul 2017 14:05:40 +0000 Received: from mail6.bemta5.messagelabs.com ([195.245.231.135]) by lists.xenproject.org with esmtp (Exim 4.84_2) (envelope-from ) id 1dSkvz-0000ZF-KU for xen-devel@lists.xenproject.org; Wed, 05 Jul 2017 14:05:39 +0000 Received: from [85.158.139.211] by server-11.bemta-5.messagelabs.com id E8/79-01729-232FC595; Wed, 05 Jul 2017 14:05:38 +0000 X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFjrJLMWRWlGSWpSXmKPExsVyuP0Ov67Rp5h IgzkLJSy+b5nM5MDocfjDFZYAxijWzLyk/IoE1oxPl3sZC/5xVjw7vZ2pgfE2RxcjJ4eEgJHE 24n/mEBsIYGFjBInvnCD2GwCqhIbrp9iBbFFBIIkNnS0AtVwcTALTGSU2Lqhga2LkYNDWEBT4 uaOOJAaFqD6Y8uPsYPYvALGEh2/TjBBzJeX6DgwmWUCI+cCRoZVjBrFqUVlqUW6RqZ6SUWZ6R kluYmZObqGBqZ6uanFxYnpqTmJScV6yfm5mxiB3qpnYGDcwbir3e8QoyQHk5Iob+XpmEghvqT 8lMqMxOKM+KLSnNTiQ4wyHBxKErz7PgDlBItS01Mr0jJzgGEDk5bg4FES4V1zByjNW1yQmFuc mQ6ROsWoy/Fqwv9vTEIsefl5qVLivDNAZgiAFGWU5sGNgIXwJUZZKWFeRgYGBiGegtSi3MwSV PlXjOIcjErCvOofgabwZOaVwG16BXQEE9ARio1gR5QkIqSkGhi5hfY7LGVmFVFiPPP6tM/yXX nfYr/camPJu73o1/oLzf5qOos/cKYe53CJKilft6B2qj+38Hf1+zOPlDmETv6h3PBkly4fr0d 3A7+9vth9r2mbOXlmesmsfzJ73+aW+T2TrHTnvIm4z8zucnmN2WHHWtPgH7fnMOtXPOct5jdI KA5037pp5mklluKMREMt5qLiRABYiZoJXAIAAA== X-Env-Sender: jgross@suse.com X-Msg-Ref: server-16.tower-206.messagelabs.com!1499263538!85664204!1 X-Originating-IP: [195.135.220.15] X-SpamReason: No, hits=0.0 required=7.0 tests= X-StarScan-Received: X-StarScan-Version: 9.4.25; banners=-,-,- X-VirusChecked: Checked Received: (qmail 29682 invoked from network); 5 Jul 2017 14:05:38 -0000 Received: from mx2.suse.de (HELO mx1.suse.de) (195.135.220.15) by server-16.tower-206.messagelabs.com with DHE-RSA-CAMELLIA256-SHA encrypted SMTP; 5 Jul 2017 14:05:38 -0000 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay1.suse.de (charybdis-ext.suse.de [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 0CDC8AD78; Wed, 5 Jul 2017 14:05:37 +0000 (UTC) From: Juergen Gross To: linux-kernel@vger.kernel.org, xen-devel@lists.xenproject.org, x86@kernel.org Date: Wed, 5 Jul 2017 16:05:20 +0200 Message-Id: <20170705140520.4948-1-jgross@suse.com> X-Mailer: git-send-email 2.12.3 Cc: Juergen Gross , stable@vger.kernel.org, mingo@redhat.com, hpa@zytor.com, boris.ostrovsky@oracle.com, tglx@linutronix.de Subject: [Xen-devel] [PATCH] xen/x86: fix cpu hotplug X-BeenThere: xen-devel@lists.xen.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: xen-devel-bounces@lists.xen.org Sender: "Xen-devel" X-Virus-Scanned: ClamAV using ClamSMTP Commit dc6416f1d711eb4c1726e845d653235dcaae12e1 ("xen/x86: Call cpu_startup_entry(CPUHP_AP_ONLINE_IDLE) from xen_play_dead()") introduced an error leading to a stack overflow of the idle task when a cpu was brought offline/online many times: by calling cpu_startup_entry() instead of returning at the end of xen_play_dead() do_idle() would be entered again and again. Don't use cpu_startup_entry(), but cpuhp_online_idle() instead allowing to return from xen_play_dead(). Cc: # 4.12 Signed-off-by: Juergen Gross Reviewed-by: Boris Ostrovsky --- For 4.11 the patch has to be backported. --- arch/x86/xen/smp_pv.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/x86/xen/smp_pv.c b/arch/x86/xen/smp_pv.c index aae32535f4ec..3e71246da5fe 100644 --- a/arch/x86/xen/smp_pv.c +++ b/arch/x86/xen/smp_pv.c @@ -19,6 +19,7 @@ #include #include #include +#include #include #include @@ -417,7 +418,7 @@ static void xen_pv_play_dead(void) /* used only with HOTPLUG_CPU */ */ tick_nohz_idle_enter(); - cpu_startup_entry(CPUHP_AP_ONLINE_IDLE); + cpuhp_online_idle(CPUHP_AP_ONLINE_IDLE); } #else /* !CONFIG_HOTPLUG_CPU */