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=-12.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT 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 0E833C00A89 for ; Mon, 2 Nov 2020 11:47:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 94DA320874 for ; Mon, 2 Nov 2020 11:47:14 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="hJ9/Ezv1" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728754AbgKBLrM (ORCPT ); Mon, 2 Nov 2020 06:47:12 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51574 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728716AbgKBLqZ (ORCPT ); Mon, 2 Nov 2020 06:46:25 -0500 Received: from mail-pf1-x443.google.com (mail-pf1-x443.google.com [IPv6:2607:f8b0:4864:20::443]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 18AD5C061A48 for ; Mon, 2 Nov 2020 03:46:24 -0800 (PST) Received: by mail-pf1-x443.google.com with SMTP id b3so10917768pfo.2 for ; Mon, 02 Nov 2020 03:46:24 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=63fCD7b9c39BMwHAue5Fl+YEtHFG3eKfVilw8x2/rAA=; b=hJ9/Ezv1ZgdvCLAG1rgjJ/9mpQ+SKh3LvAYZ/WUKYXIalESoV9Oql4vEQPCT2oMRus Drdj9tN3YSjMyBl+gq1AeNPOpvihBVmc1GU7Jm/9saZgCQNc7QuyUJilIvyNHRHrw9VW fY1y9FZJNr/taNUexlK7F8FnmRslj7+n7UVcb6vdTIfHXDkMGs9Vv+EQPz03XeTpwM4T y0sxHRkvp7vk08etU9dCuWcROXesLKCqMHWaZ93iaANXXu+HO+gONdCfJ23JAcZbp6zr 1PC8Lnkk0Pilok7g7Kx4MQXncXBIwSgsu/qS0WXMl5HrPqZek7EGWxjeoaUiBFo3oGqX Q5Jw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=63fCD7b9c39BMwHAue5Fl+YEtHFG3eKfVilw8x2/rAA=; b=CAhDoli4TsNHo1zgFo6YKPbv49MGcZCKJYVpBM0nnYGxbW4NERsdc8+Dn6WdUMmONF arsQ6hfqNS+jwSVxUGXIvhXM1kWBGRi+lK6ZR1jFq6RTl7T5O/SUadbB6j19cYkEMHsY jgJj0WwwISptj5LN+vvsJH/lw98oZvm0glRtkJlf0q0wLNY/AG/uviZZNlcq80Jt6eSV oq9e0HNtOYhB9sLscskXy2ATCl7kwCd3/L2nmFqTIqQiEoMjdMd+4T31xYDnJlteZofz ojlzJiMgBT52hx/RYNsm+AhV6R5GvmLP/E/ttjGiDE3WneSaJUrJ4CH1CaM1fQ5fsf2M b5tQ== X-Gm-Message-State: AOAM530DlLmElmIGEkCZq44k1Wgvrxn1tyOYmt94IfTeBvJ/AgOawkJv IAJ8slg+kf9vmM4mgfXmbyVlfw== X-Google-Smtp-Source: ABdhPJxo+jJRsFTKov77OJRU77007ycelGKbPaV5dYEs45Z4UJIU+NvAvFXsfZkDaHO0m3EtjWrM2A== X-Received: by 2002:a63:3d8c:: with SMTP id k134mr12755914pga.22.1604317583680; Mon, 02 Nov 2020 03:46:23 -0800 (PST) Received: from localhost.localdomain ([122.173.169.225]) by smtp.gmail.com with ESMTPSA id y5sm14276184pfq.79.2020.11.02.03.46.15 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Mon, 02 Nov 2020 03:46:22 -0800 (PST) From: Sumit Garg To: maz@kernel.org, catalin.marinas@arm.com, will@kernel.org, daniel.thompson@linaro.org Cc: linux-arm-kernel@lists.infradead.org, tglx@linutronix.de, jason@lakedaemon.net, linux@armlinux.org.uk, tsbogend@alpha.franken.de, mpe@ellerman.id.au, davem@davemloft.net, mingo@redhat.com, bp@alien8.de, x86@kernel.org, mark.rutland@arm.com, julien.thierry.kdev@gmail.com, dianders@chromium.org, jason.wessel@windriver.com, msys.mizuma@gmail.com, ito-yuichi@fujitsu.com, kgdb-bugreport@lists.sourceforge.net, linux-kernel@vger.kernel.org, Sumit Garg Subject: [PATCH v7 5/7] arm64: ipi_nmi: Add support for NMI backtrace Date: Mon, 2 Nov 2020 17:14:45 +0530 Message-Id: <1604317487-14543-6-git-send-email-sumit.garg@linaro.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1604317487-14543-1-git-send-email-sumit.garg@linaro.org> References: <1604317487-14543-1-git-send-email-sumit.garg@linaro.org> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Enable NMI backtrace support on arm64 using IPI turned as an NMI leveraging pseudo NMIs support. It is now possible for users to get a backtrace of a CPU stuck in hard-lockup using magic SYSRQ. Signed-off-by: Sumit Garg --- arch/arm64/include/asm/irq.h | 6 ++++++ arch/arm64/kernel/ipi_nmi.c | 18 ++++++++++++++++-- 2 files changed, 22 insertions(+), 2 deletions(-) diff --git a/arch/arm64/include/asm/irq.h b/arch/arm64/include/asm/irq.h index b2b0c64..ef018a8 100644 --- a/arch/arm64/include/asm/irq.h +++ b/arch/arm64/include/asm/irq.h @@ -6,6 +6,12 @@ #include +#ifdef CONFIG_SMP +extern bool arch_trigger_cpumask_backtrace(const cpumask_t *mask, + bool exclude_self); +#define arch_trigger_cpumask_backtrace arch_trigger_cpumask_backtrace +#endif + struct pt_regs; static inline int nr_legacy_irqs(void) diff --git a/arch/arm64/kernel/ipi_nmi.c b/arch/arm64/kernel/ipi_nmi.c index a945dcf..597dcf7 100644 --- a/arch/arm64/kernel/ipi_nmi.c +++ b/arch/arm64/kernel/ipi_nmi.c @@ -8,6 +8,7 @@ #include #include +#include #include #include @@ -31,11 +32,24 @@ void arm64_send_nmi(cpumask_t *mask) __ipi_send_mask(ipi_nmi_desc, mask); } +bool arch_trigger_cpumask_backtrace(const cpumask_t *mask, bool exclude_self) +{ + if (!ipi_nmi_desc) + return false; + + nmi_trigger_cpumask_backtrace(mask, exclude_self, arm64_send_nmi); + + return true; +} + static irqreturn_t ipi_nmi_handler(int irq, void *data) { - /* nop, NMI handlers for special features can be added here. */ + irqreturn_t ret = IRQ_NONE; + + if (nmi_cpu_backtrace(get_irq_regs())) + ret = IRQ_HANDLED; - return IRQ_NONE; + return ret; } void dynamic_ipi_setup(int cpu) -- 2.7.4