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=-13.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,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 1C243C433E0 for ; Sat, 8 Aug 2020 23:45:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E802620672 for ; Sat, 8 Aug 2020 23:45:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1596930344; bh=D4uOVfmK8r16ZLtQRciHwUAqJs5/GQ9VClTO3FyuCr4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=2RAmOFRmp2EcHQ85M/hg7WugbuhgTlF8XQqAkabYe7aMDyZh12p/2nbvn6T8PREkS obcqsYW41VIy8uBpLRuAEGre1cw+rGSVGeIsOz800jz+n18hnDZhwumFqTTg2hX9TN CowbAJTxehDt4xdKdbyU9cAgq4KqnTCHJUeXH6Gg= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728780AbgHHXpn (ORCPT ); Sat, 8 Aug 2020 19:45:43 -0400 Received: from mail.kernel.org ([198.145.29.99]:52688 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728305AbgHHXih (ORCPT ); Sat, 8 Aug 2020 19:38:37 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 70EBD2073E; Sat, 8 Aug 2020 23:38:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1596929917; bh=D4uOVfmK8r16ZLtQRciHwUAqJs5/GQ9VClTO3FyuCr4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=krfcj15aVAEn2sNzyIm00+bykc6ja7SDeFbJutQsxN0EmsEZq07dGvq+ml03oWb09 yphQeuq0oguSZ1d+ZmCsEMBMLLSZwCpXLNLb97c9GrpDPFEVTD01FU7nWA6SmUCsZx ka7r70mle1jkaQmGQ2+3WpAHF38GAmlZA1hYQjmU= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Zenghui Yu , Marc Zyngier , Sasha Levin Subject: [PATCH AUTOSEL 5.7 53/58] irqchip/gic-v4.1: Use GFP_ATOMIC flag in allocate_vpe_l1_table() Date: Sat, 8 Aug 2020 19:37:19 -0400 Message-Id: <20200808233724.3618168-53-sashal@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200808233724.3618168-1-sashal@kernel.org> References: <20200808233724.3618168-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Zenghui Yu [ Upstream commit d1bd7e0ba533a2a6f313579ec9b504f6614c35c4 ] Booting the latest kernel with DEBUG_ATOMIC_SLEEP=y on a GICv4.1 enabled box, I get the following kernel splat: [ 0.053766] BUG: sleeping function called from invalid context at mm/slab.h:567 [ 0.053767] in_atomic(): 1, irqs_disabled(): 128, non_block: 0, pid: 0, name: swapper/1 [ 0.053769] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.8.0-rc3+ #23 [ 0.053770] Call trace: [ 0.053774] dump_backtrace+0x0/0x218 [ 0.053775] show_stack+0x2c/0x38 [ 0.053777] dump_stack+0xc4/0x10c [ 0.053779] ___might_sleep+0xfc/0x140 [ 0.053780] __might_sleep+0x58/0x90 [ 0.053782] slab_pre_alloc_hook+0x7c/0x90 [ 0.053783] kmem_cache_alloc_trace+0x60/0x2f0 [ 0.053785] its_cpu_init+0x6f4/0xe40 [ 0.053786] gic_starting_cpu+0x24/0x38 [ 0.053788] cpuhp_invoke_callback+0xa0/0x710 [ 0.053789] notify_cpu_starting+0xcc/0xd8 [ 0.053790] secondary_start_kernel+0x148/0x200 # ./scripts/faddr2line vmlinux its_cpu_init+0x6f4/0xe40 its_cpu_init+0x6f4/0xe40: allocate_vpe_l1_table at drivers/irqchip/irq-gic-v3-its.c:2818 (inlined by) its_cpu_init_lpis at drivers/irqchip/irq-gic-v3-its.c:3138 (inlined by) its_cpu_init at drivers/irqchip/irq-gic-v3-its.c:5166 It turned out that we're allocating memory using GFP_KERNEL (may sleep) within the CPU hotplug notifier, which is indeed an atomic context. Bad thing may happen if we're playing on a system with more than a single CommonLPIAff group. Avoid it by turning this into an atomic allocation. Fixes: 5e5168461c22 ("irqchip/gic-v4.1: VPE table (aka GICR_VPROPBASER) allocation") Signed-off-by: Zenghui Yu Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20200630133746.816-1-yuzenghui@huawei.com Signed-off-by: Sasha Levin --- drivers/irqchip/irq-gic-v3-its.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c index b99e3105bf9fe..237c832acdd77 100644 --- a/drivers/irqchip/irq-gic-v3-its.c +++ b/drivers/irqchip/irq-gic-v3-its.c @@ -2690,7 +2690,7 @@ static int allocate_vpe_l1_table(void) if (val & GICR_VPROPBASER_4_1_VALID) goto out; - gic_data_rdist()->vpe_table_mask = kzalloc(sizeof(cpumask_t), GFP_KERNEL); + gic_data_rdist()->vpe_table_mask = kzalloc(sizeof(cpumask_t), GFP_ATOMIC); if (!gic_data_rdist()->vpe_table_mask) return -ENOMEM; @@ -2757,7 +2757,7 @@ static int allocate_vpe_l1_table(void) pr_debug("np = %d, npg = %lld, psz = %d, epp = %d, esz = %d\n", np, npg, psz, epp, esz); - page = alloc_pages(GFP_KERNEL | __GFP_ZERO, get_order(np * PAGE_SIZE)); + page = alloc_pages(GFP_ATOMIC | __GFP_ZERO, get_order(np * PAGE_SIZE)); if (!page) return -ENOMEM; -- 2.25.1