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 9055FC433E2 for ; Fri, 11 Sep 2020 16:22:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 46077208FE for ; Fri, 11 Sep 2020 16:22:15 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="EuQDuBTv" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726635AbgIKQWO (ORCPT ); Fri, 11 Sep 2020 12:22:14 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33966 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726495AbgIKP2P (ORCPT ); Fri, 11 Sep 2020 11:28:15 -0400 Received: from mail-pj1-x1044.google.com (mail-pj1-x1044.google.com [IPv6:2607:f8b0:4864:20::1044]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 72911C061799 for ; Fri, 11 Sep 2020 06:29:43 -0700 (PDT) Received: by mail-pj1-x1044.google.com with SMTP id b17so1713540pji.1 for ; Fri, 11 Sep 2020 06:29:43 -0700 (PDT) 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=UMF4bf/xlX5iMhhFdvv4POZJxLXNJMbFMY0/ylfkgBU=; b=EuQDuBTvOvwLK210071x8IREFokQkgZaord4oFCyWIF92/r5O+/EHGVhTZB7Xa3ZYA O6Y2+67Gs5ian2S/VK+fTAa2hAr+hTP0YsK989soxdqSat1sWOjtSlXx5AUdQdheN/r7 l+FNLv+QNEE9hzRIazVRwnfqsbKvqZLqCiwKBW/iegqkTtCcFFxV4oK/Aay+X8OFVNwt ea7F6VWqHxZ4ol/1WXrJ5YTrlZSyygzFH08zKGn8NikhCkP2wRHgnIytnzENhf+9t8q5 EeOBCzZuDaOq0opR7A5YOpMF84iYa5OGzmk8Wn8tzIGeF3MAZphGwwlyFNNa9ikyVoXk rKMg== 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=UMF4bf/xlX5iMhhFdvv4POZJxLXNJMbFMY0/ylfkgBU=; b=hZoxVkyWg+3+o88Pe/kpu+f5z8aH1nY2iX4MkCFuCeLLdNaJx+aQL4YBsG9OmQeMTb akofBzFNFPJ+1DBXBRGlwvnULtD3HZAjBeKyjFowpWewOoaUcOdk4bTzPo2BikwpgP1X lG8FOsHvI39Ag7ORZqvyW5s4HtmRsArrPvLtaIlOQPCnRcUJsex5/ewGMoTakFHktCHG QJbmy4PEoNJTm9XywitfzyGhu1FGtxAwyxX2kHWg/1Np7WwQBiXbWG/VkwSN7pTgBGLM mIN+qpt03kficfcJZVY5CrF52JMFNDcp9P3O6wzaVQYqvFGJTEDoxnH2ZelfIzwYpquZ csNg== X-Gm-Message-State: AOAM530fq/q0akv443nbpvTBHEWACkHD3SmchkmjFsOeecMXrnlJMcp3 REEG6NHGeF7hgWAVLsjKGMP0lg== X-Google-Smtp-Source: ABdhPJxB8cUOtjFdM+vSMsIEhsYFJvwax+iseMhfwh9gbEQK9y8yNt7VouZeSvdSOUYF8uN7QozcNQ== X-Received: by 2002:a17:90a:f992:: with SMTP id cq18mr2296365pjb.136.1599830983031; Fri, 11 Sep 2020 06:29:43 -0700 (PDT) Received: from localhost.localdomain ([117.210.209.48]) by smtp.gmail.com with ESMTPSA id e10sm557988pgb.45.2020.09.11.06.29.35 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Fri, 11 Sep 2020 06:29:42 -0700 (PDT) From: Sumit Garg To: maz@kernel.org, catalin.marinas@arm.com, will@kernel.org Cc: linux-arm-kernel@lists.infradead.org, tglx@linutronix.de, jason@lakedaemon.net, mark.rutland@arm.com, julien.thierry.kdev@gmail.com, dianders@chromium.org, daniel.thompson@linaro.org, jason.wessel@windriver.com, kgdb-bugreport@lists.sourceforge.net, linux-kernel@vger.kernel.org, Sumit Garg Subject: [PATCH v4 5/5] arm64: ipi_nmi: Add support for NMI backtrace Date: Fri, 11 Sep 2020 18:58:44 +0530 Message-Id: <1599830924-13990-6-git-send-email-sumit.garg@linaro.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1599830924-13990-1-git-send-email-sumit.garg@linaro.org> References: <1599830924-13990-1-git-send-email-sumit.garg@linaro.org> Sender: linux-kernel-owner@vger.kernel.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 | 12 +++++++++++- 2 files changed, 17 insertions(+), 1 deletion(-) diff --git a/arch/arm64/include/asm/irq.h b/arch/arm64/include/asm/irq.h index b2b0c64..e840bf1 100644 --- a/arch/arm64/include/asm/irq.h +++ b/arch/arm64/include/asm/irq.h @@ -6,6 +6,12 @@ #include +#ifdef CONFIG_SMP +extern void 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 627bc11..d3aa430 100644 --- a/arch/arm64/kernel/ipi_nmi.c +++ b/arch/arm64/kernel/ipi_nmi.c @@ -9,6 +9,7 @@ #include #include #include +#include #include #include @@ -25,12 +26,21 @@ void arch_send_call_nmi_func_ipi_mask(cpumask_t *mask) __ipi_send_mask(ipi_desc, mask); } +void arch_trigger_cpumask_backtrace(const cpumask_t *mask, bool exclude_self) +{ + nmi_trigger_cpumask_backtrace(mask, exclude_self, + arch_send_call_nmi_func_ipi_mask); +} + static irqreturn_t ipi_nmi_handler(int irq, void *data) { unsigned int cpu = smp_processor_id(); - ipi_kgdb_nmicallback(cpu, get_irq_regs()); + if (nmi_cpu_backtrace(get_irq_regs())) + goto out; + ipi_kgdb_nmicallback(cpu, get_irq_regs()); +out: return IRQ_HANDLED; } -- 2.7.4