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=-13.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 A4EADC433F5 for ; Thu, 16 Sep 2021 12:16:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 898A76120D for ; Thu, 16 Sep 2021 12:16:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239418AbhIPMRb (ORCPT ); Thu, 16 Sep 2021 08:17:31 -0400 Received: from mail.kernel.org ([198.145.29.99]:33304 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239367AbhIPMRa (ORCPT ); Thu, 16 Sep 2021 08:17:30 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id EBAF460F4A; Thu, 16 Sep 2021 12:16:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1631794570; bh=7h3NyJpMbuyKhJbRDijEfzWZZarVy6pIX9tDAzhitW4=; h=Subject:To:Cc:From:Date:From; b=BjbtQwD5UR+fLWYjzFJr26P8DAVMZoucEKf2M521Ja+lV5RALjz/tCwnyXIHVfjkF m3vXRsGz98qqDCQ2WaShVfwnGgWOindYwQA72MUltQ8F3ZZA7DP6DLGt88xcXzlNrw oaOS33fCA3tAzyLNhwa0iL2k+aZ0aQ2X125ZAt8I= Subject: FAILED: patch "[PATCH] s390/topology: fix topology information when calling cpu" failed to apply to 5.10-stable tree To: svens@linux.ibm.com, hca@linux.ibm.com, stable@vger.kernel.org Cc: From: Date: Thu, 16 Sep 2021 14:16:08 +0200 Message-ID: <163179456820396@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org The patch below does not apply to the 5.10-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From a052096bdd6809eeab809202726634d1ac975aa1 Mon Sep 17 00:00:00 2001 From: Sven Schnelle Date: Fri, 27 Aug 2021 20:21:05 +0200 Subject: [PATCH] s390/topology: fix topology information when calling cpu hotplug notifiers The cpu hotplug notifiers are called without updating the core/thread masks when a new CPU is added. This causes problems with code setting up data structures in a cpu hotplug notifier, and relying on that later in normal code. This caused a crash in the new core scheduling code (SCHED_CORE), where rq->core was set up in a notifier depending on cpu masks. To fix this, add a cpu_setup_mask which is used in update_cpu_masks() instead of the cpu_online_mask to determine whether the cpu masks should be set for a certain cpu. Also move update_cpu_masks() to update the masks before calling notify_cpu_starting() so that the notifiers are seeing the updated masks. Signed-off-by: Sven Schnelle Cc: [hca@linux.ibm.com: get rid of cpu_online_mask handling] Signed-off-by: Heiko Carstens diff --git a/arch/s390/include/asm/smp.h b/arch/s390/include/asm/smp.h index e317fd4866c1..f16f4d054ae2 100644 --- a/arch/s390/include/asm/smp.h +++ b/arch/s390/include/asm/smp.h @@ -18,6 +18,7 @@ extern struct mutex smp_cpu_state_mutex; extern unsigned int smp_cpu_mt_shift; extern unsigned int smp_cpu_mtid; extern __vector128 __initdata boot_cpu_vector_save_area[__NUM_VXRS]; +extern cpumask_t cpu_setup_mask; extern int __cpu_up(unsigned int cpu, struct task_struct *tidle); diff --git a/arch/s390/kernel/smp.c b/arch/s390/kernel/smp.c index 2a991e43ead3..1a04e5bdf655 100644 --- a/arch/s390/kernel/smp.c +++ b/arch/s390/kernel/smp.c @@ -95,6 +95,7 @@ __vector128 __initdata boot_cpu_vector_save_area[__NUM_VXRS]; #endif static unsigned int smp_max_threads __initdata = -1U; +cpumask_t cpu_setup_mask; static int __init early_nosmt(char *s) { @@ -902,13 +903,14 @@ static void smp_start_secondary(void *cpuvoid) vtime_init(); vdso_getcpu_init(); pfault_init(); + cpumask_set_cpu(cpu, &cpu_setup_mask); + update_cpu_masks(); notify_cpu_starting(cpu); if (topology_cpu_dedicated(cpu)) set_cpu_flag(CIF_DEDICATED_CPU); else clear_cpu_flag(CIF_DEDICATED_CPU); set_cpu_online(cpu, true); - update_cpu_masks(); inc_irq_stat(CPU_RST); local_irq_enable(); cpu_startup_entry(CPUHP_AP_ONLINE_IDLE); @@ -950,10 +952,13 @@ early_param("possible_cpus", _setup_possible_cpus); int __cpu_disable(void) { unsigned long cregs[16]; + int cpu; /* Handle possible pending IPIs */ smp_handle_ext_call(); - set_cpu_online(smp_processor_id(), false); + cpu = smp_processor_id(); + set_cpu_online(cpu, false); + cpumask_clear_cpu(cpu, &cpu_setup_mask); update_cpu_masks(); /* Disable pseudo page faults on this cpu. */ pfault_fini(); diff --git a/arch/s390/kernel/topology.c b/arch/s390/kernel/topology.c index d2458a29618f..58f8291950cb 100644 --- a/arch/s390/kernel/topology.c +++ b/arch/s390/kernel/topology.c @@ -67,7 +67,7 @@ static void cpu_group_map(cpumask_t *dst, struct mask_info *info, unsigned int c static cpumask_t mask; cpumask_clear(&mask); - if (!cpu_online(cpu)) + if (!cpumask_test_cpu(cpu, &cpu_setup_mask)) goto out; cpumask_set_cpu(cpu, &mask); switch (topology_mode) { @@ -88,7 +88,7 @@ static void cpu_group_map(cpumask_t *dst, struct mask_info *info, unsigned int c case TOPOLOGY_MODE_SINGLE: break; } - cpumask_and(&mask, &mask, cpu_online_mask); + cpumask_and(&mask, &mask, &cpu_setup_mask); out: cpumask_copy(dst, &mask); } @@ -99,16 +99,16 @@ static void cpu_thread_map(cpumask_t *dst, unsigned int cpu) int i; cpumask_clear(&mask); - if (!cpu_online(cpu)) + if (!cpumask_test_cpu(cpu, &cpu_setup_mask)) goto out; cpumask_set_cpu(cpu, &mask); if (topology_mode != TOPOLOGY_MODE_HW) goto out; cpu -= cpu % (smp_cpu_mtid + 1); - for (i = 0; i <= smp_cpu_mtid; i++) - if (cpu_present(cpu + i)) + for (i = 0; i <= smp_cpu_mtid; i++) { + if (cpumask_test_cpu(cpu + i, &cpu_setup_mask)) cpumask_set_cpu(cpu + i, &mask); - cpumask_and(&mask, &mask, cpu_online_mask); + } out: cpumask_copy(dst, &mask); } @@ -569,6 +569,7 @@ void __init topology_init_early(void) alloc_masks(info, &book_info, 2); alloc_masks(info, &drawer_info, 3); out: + cpumask_set_cpu(0, &cpu_setup_mask); __arch_update_cpu_topology(); __arch_update_dedicated_flag(NULL); }