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=-9.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,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 7D6F8C4360F for ; Thu, 4 Apr 2019 09:53:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4EBBE206DD for ; Thu, 4 Apr 2019 09:53:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1554371620; bh=bZ9bLe04KQrD6HJQG1lTxqoBo83ACV2LEst1TRO0XCw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=yvY2CojUEK3Tm5pHTWcS1d5zHvOttNisTqBdbTdBJEHHrDBd6RvmbeM6TdN21wf7M T354ebmlLtIY5WuVrAq+sU7WHT2CU6ZksrqFfnOzMl+DFVhpnXUe0lwPaiWKhTC7fB /P7UYSyhHXrS7GEWORYHQH/eNw0J1sPbBvNA0/r4= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729751AbfDDIxM (ORCPT ); Thu, 4 Apr 2019 04:53:12 -0400 Received: from mail.kernel.org ([198.145.29.99]:55406 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729743AbfDDIxL (ORCPT ); Thu, 4 Apr 2019 04:53:11 -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 F2DFC20882; Thu, 4 Apr 2019 08:53:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1554367990; bh=bZ9bLe04KQrD6HJQG1lTxqoBo83ACV2LEst1TRO0XCw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ZDmcRuG30+V0613jgIvV8nWEvC1xUl8XMBLATBaKmVjZGTd/E1CGOXZGD6W+ReCWD /nJyoctCAPK7iILcTei1cUHPEPHI5TRkZGWkEANjb+2j5r9to2mxHhTKx4zZCg5Mmt BsHZ/dHeC8Ixhrjz+7K8Yzwa7WMgFM5qsAz98CGQ= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Nathan Fontenot , "Michael W. Bringmann" , Michael Ellerman , Sasha Levin Subject: [PATCH 4.9 73/91] powerpc/pseries: Perform full re-add of CPU for topology update post-migration Date: Thu, 4 Apr 2019 10:47:57 +0200 Message-Id: <20190404084539.674973415@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190404084535.450029272@linuxfoundation.org> References: <20190404084535.450029272@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ [ Upstream commit 81b61324922c67f73813d8a9c175f3c153f6a1c6 ] On pseries systems, performing a partition migration can result in altering the nodes a CPU is assigned to on the destination system. For exampl, pre-migration on the source system CPUs are in node 1 and 3, post-migration on the destination system CPUs are in nodes 2 and 3. Handling the node change for a CPU can cause corruption in the slab cache if we hit a timing where a CPUs node is changed while cache_reap() is invoked. The corruption occurs because the slab cache code appears to rely on the CPU and slab cache pages being on the same node. The current dynamic updating of a CPUs node done in arch/powerpc/mm/numa.c does not prevent us from hitting this scenario. Changing the device tree property update notification handler that recognizes an affinity change for a CPU to do a full DLPAR remove and add of the CPU instead of dynamically changing its node resolves this issue. Signed-off-by: Nathan Fontenot Signed-off-by: Michael W. Bringmann Tested-by: Michael W. Bringmann Signed-off-by: Michael Ellerman Signed-off-by: Sasha Levin --- arch/powerpc/include/asm/topology.h | 2 ++ arch/powerpc/mm/numa.c | 9 +-------- arch/powerpc/platforms/pseries/hotplug-cpu.c | 19 +++++++++++++++++++ 3 files changed, 22 insertions(+), 8 deletions(-) diff --git a/arch/powerpc/include/asm/topology.h b/arch/powerpc/include/asm/topology.h index 8b3b46b7b0f2..229c91bcf616 100644 --- a/arch/powerpc/include/asm/topology.h +++ b/arch/powerpc/include/asm/topology.h @@ -90,6 +90,8 @@ static inline int prrn_is_enabled(void) #define topology_sibling_cpumask(cpu) (per_cpu(cpu_sibling_map, cpu)) #define topology_core_cpumask(cpu) (per_cpu(cpu_core_map, cpu)) #define topology_core_id(cpu) (cpu_to_core_id(cpu)) + +int dlpar_cpu_readd(int cpu); #endif #endif diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c index 0ef83c274019..9cad2ed812ab 100644 --- a/arch/powerpc/mm/numa.c +++ b/arch/powerpc/mm/numa.c @@ -1540,13 +1540,6 @@ static void reset_topology_timer(void) #ifdef CONFIG_SMP -static void stage_topology_update(int core_id) -{ - cpumask_or(&cpu_associativity_changes_mask, - &cpu_associativity_changes_mask, cpu_sibling_mask(core_id)); - reset_topology_timer(); -} - static int dt_update_callback(struct notifier_block *nb, unsigned long action, void *data) { @@ -1559,7 +1552,7 @@ static int dt_update_callback(struct notifier_block *nb, !of_prop_cmp(update->prop->name, "ibm,associativity")) { u32 core_id; of_property_read_u32(update->dn, "reg", &core_id); - stage_topology_update(core_id); + rc = dlpar_cpu_readd(core_id); rc = NOTIFY_OK; } break; diff --git a/arch/powerpc/platforms/pseries/hotplug-cpu.c b/arch/powerpc/platforms/pseries/hotplug-cpu.c index a1b63e00b2f7..7a2beedb9740 100644 --- a/arch/powerpc/platforms/pseries/hotplug-cpu.c +++ b/arch/powerpc/platforms/pseries/hotplug-cpu.c @@ -785,6 +785,25 @@ static int dlpar_cpu_add_by_count(u32 cpus_to_add) return rc; } +int dlpar_cpu_readd(int cpu) +{ + struct device_node *dn; + struct device *dev; + u32 drc_index; + int rc; + + dev = get_cpu_device(cpu); + dn = dev->of_node; + + rc = of_property_read_u32(dn, "ibm,my-drc-index", &drc_index); + + rc = dlpar_cpu_remove_by_index(drc_index); + if (!rc) + rc = dlpar_cpu_add(drc_index); + + return rc; +} + int dlpar_cpu(struct pseries_hp_errorlog *hp_elog) { u32 count, drc_index; -- 2.19.1