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=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 7F762C7618E for ; Mon, 29 Jul 2019 19:48:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4AA4421655 for ; Mon, 29 Jul 2019 19:48:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1564429697; bh=a20IC1hebj4tVMxQzZWl+3FHx5FTgJbKJxxAffv3wEM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=ygCdlhlSjwWjUb7XxeubVWUOrcmE2isfrXvCRYHO30GbHiIC9UR/nPt+JPTX/nmRn kN/Kw//c/Z1mamJ7++ZBGAMEMqStep1rPAZw8l29Dm9pwvH7G4SXj0vFfhiRjjqbza RlCKBbXIyZ77YkMKDAQh2VuJHL0vfScm1Fa0hEtg= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390106AbfG2TsP (ORCPT ); Mon, 29 Jul 2019 15:48:15 -0400 Received: from mail.kernel.org ([198.145.29.99]:38216 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729696AbfG2TsK (ORCPT ); Mon, 29 Jul 2019 15:48:10 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id B215720C01; Mon, 29 Jul 2019 19:48:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1564429690; bh=a20IC1hebj4tVMxQzZWl+3FHx5FTgJbKJxxAffv3wEM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=M3roj78T79fAkXtYbZII4rZwvice8uwhGu4k281KKBgtZabLi4ThL6dbDMH7uCXQP MTe8bpiyj6toPKUJ+CjEW2dkZHPmv1QxEvYEUcZqQG2eWp2Vq+cG8Su3Mh4l6Ed08G M70VelvJqBKC/dIbcG8madBEmBrUq/WDJ/q6aky8= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Nathan Lynch , "Gautham R. Shenoy" , Michael Ellerman , Sasha Levin Subject: [PATCH 5.2 062/215] powerpc/pseries/mobility: prevent cpu hotplug during DT update Date: Mon, 29 Jul 2019 21:20:58 +0200 Message-Id: <20190729190751.252069499@linuxfoundation.org> X-Mailer: git-send-email 2.22.0 In-Reply-To: <20190729190739.971253303@linuxfoundation.org> References: <20190729190739.971253303@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org [ Upstream commit e59a175faa8df9d674247946f2a5a9c29c835725 ] CPU online/offline code paths are sensitive to parts of the device tree (various cpu node properties, cache nodes) that can be changed as a result of a migration. Prevent CPU hotplug while the device tree potentially is inconsistent. Fixes: 410bccf97881 ("powerpc/pseries: Partition migration in the kernel") Signed-off-by: Nathan Lynch Reviewed-by: Gautham R. Shenoy Signed-off-by: Michael Ellerman Signed-off-by: Sasha Levin --- arch/powerpc/platforms/pseries/mobility.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/arch/powerpc/platforms/pseries/mobility.c b/arch/powerpc/platforms/pseries/mobility.c index 0c48c8964783..50e7aee3c7f3 100644 --- a/arch/powerpc/platforms/pseries/mobility.c +++ b/arch/powerpc/platforms/pseries/mobility.c @@ -6,6 +6,7 @@ * Copyright (C) 2010 IBM Corporation */ +#include #include #include #include @@ -335,11 +336,19 @@ void post_mobility_fixup(void) if (rc) printk(KERN_ERR "Post-mobility activate-fw failed: %d\n", rc); + /* + * We don't want CPUs to go online/offline while the device + * tree is being updated. + */ + cpus_read_lock(); + rc = pseries_devicetree_update(MIGRATION_SCOPE); if (rc) printk(KERN_ERR "Post-mobility device tree update " "failed: %d\n", rc); + cpus_read_unlock(); + /* Possibly switch to a new RFI flush type */ pseries_setup_rfi_flush(); -- 2.20.1