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 74711C00A89 for ; Mon, 2 Nov 2020 11:47:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0D64920786 for ; Mon, 2 Nov 2020 11:47:09 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="uCcmpbko" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728740AbgKBLrJ (ORCPT ); Mon, 2 Nov 2020 06:47:09 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51620 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728644AbgKBLqn (ORCPT ); Mon, 2 Nov 2020 06:46:43 -0500 Received: from mail-pf1-x444.google.com (mail-pf1-x444.google.com [IPv6:2607:f8b0:4864:20::444]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8348AC0617A6 for ; Mon, 2 Nov 2020 03:46:40 -0800 (PST) Received: by mail-pf1-x444.google.com with SMTP id c20so10885452pfr.8 for ; Mon, 02 Nov 2020 03:46:40 -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=JyvPCaqqbOYfCXpYx0pOVqmUQ12hYhEPEwMON22pNjk=; b=uCcmpbkowm5jgVzKL5iyPFHUhu/8J3iCv9LXeYwdXeL0hGI1Lcu7XVewGbCxodYOqi Uf67FbBxpsW5SKTmkpPHTDL0w4EiYZX7WMblNDDAm4+FSg4Hs+wZ9Sz70B3pUHPF0oQn 44q18yg4+jIlgmULBSgTvbTsnwRC7b+YmVZjZXlDoYyc85PDhTsi+645DPsajTudK96v mNa/J+dBSFYD1BopcjX4zTxQY5Om0JD0iUcYMz9arNALeRncogCniUb1qlIj+sC1q+2m 7DmOPf0nu6RNqv7qF4L0V8P1R/n2xF3qKsCA1IbccTPBH7b0sTq75OoLX8vrU91wvE4Q bFww== 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=JyvPCaqqbOYfCXpYx0pOVqmUQ12hYhEPEwMON22pNjk=; b=OMp+3xpL6h6CwIBnebjlfM6EM5A+QWG8DjKcZWQVeDWYpg4XRb1q8UfeMXTC1MUw9t 7CgdbqS/cQBoLon5Tjd6jUsnAzKzSz055d3I6dDehYlIL/raIYB0myz2k002/0qxJy/y grILsF4hY5GxaiKUd9n8JsxwCMRTU+omcyMK2cnimOL6ItNDhDUznxfH3DdCy6a6R93w XFMVi05OEqzk4ufmGOszRdCyO6uLQfZGGfEXyGpqnxCfTAZu/JJUBIyPLHb+MHttEnOh uubuCxDPYzPZFeixtbcNu1o4vQajrRHfRbKyEnXklWCF7luTmctUnIVCFO1cg3e15Q/q s3+Q== X-Gm-Message-State: AOAM532LO53FdfuixJ8uhwGCl32EHoh0PnJtdyRRFYW+2/rs4qOzrtVs GttKXQW13sdZBD8n6IQAyr/XVA== X-Google-Smtp-Source: ABdhPJxya51ixKRZ4J+w5F3LFYNiyvEMS5yCU1E+CoRLMD+YzEfvZmLOlP27VhF4kmnTj0B5cnUOLQ== X-Received: by 2002:a17:90b:111:: with SMTP id p17mr17762114pjz.159.1604317600138; Mon, 02 Nov 2020 03:46:40 -0800 (PST) Received: from localhost.localdomain ([122.173.169.225]) by smtp.gmail.com with ESMTPSA id y5sm14276184pfq.79.2020.11.02.03.46.32 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Mon, 02 Nov 2020 03:46:39 -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 7/7] arm64: kgdb: Roundup cpus using IPI as NMI Date: Mon, 2 Nov 2020 17:14:47 +0530 Message-Id: <1604317487-14543-8-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 arm64 platforms with GICv3 or later supports pseudo NMIs which can be leveraged to roundup CPUs which are stuck in hard lockup state with interrupts disabled that wouldn't be possible with a normal IPI. So instead switch to roundup CPUs using IPI turned as NMI. And in case a particular arm64 platform doesn't supports pseudo NMIs, it will switch back to default kgdb CPUs roundup mechanism. Signed-off-by: Sumit Garg --- arch/arm64/kernel/ipi_nmi.c | 5 +++++ arch/arm64/kernel/kgdb.c | 18 ++++++++++++++++++ 2 files changed, 23 insertions(+) diff --git a/arch/arm64/kernel/ipi_nmi.c b/arch/arm64/kernel/ipi_nmi.c index 597dcf7..898d69c 100644 --- a/arch/arm64/kernel/ipi_nmi.c +++ b/arch/arm64/kernel/ipi_nmi.c @@ -8,6 +8,7 @@ #include #include +#include #include #include @@ -45,10 +46,14 @@ bool arch_trigger_cpumask_backtrace(const cpumask_t *mask, bool exclude_self) static irqreturn_t ipi_nmi_handler(int irq, void *data) { irqreturn_t ret = IRQ_NONE; + unsigned int cpu = smp_processor_id(); if (nmi_cpu_backtrace(get_irq_regs())) ret = IRQ_HANDLED; + if (!kgdb_nmicallback(cpu, get_irq_regs())) + ret = IRQ_HANDLED; + return ret; } diff --git a/arch/arm64/kernel/kgdb.c b/arch/arm64/kernel/kgdb.c index 1a157ca3..371b176 100644 --- a/arch/arm64/kernel/kgdb.c +++ b/arch/arm64/kernel/kgdb.c @@ -17,6 +17,7 @@ #include #include +#include #include struct dbg_reg_def_t dbg_reg_def[DBG_MAX_REG_NUM] = { @@ -353,3 +354,20 @@ int kgdb_arch_remove_breakpoint(struct kgdb_bkpt *bpt) return aarch64_insn_write((void *)bpt->bpt_addr, *(u32 *)bpt->saved_instr); } + +void kgdb_roundup_cpus(void) +{ + struct cpumask mask; + + if (!arm64_supports_nmi()) { + kgdb_smp_call_nmi_hook(); + return; + } + + cpumask_copy(&mask, cpu_online_mask); + cpumask_clear_cpu(raw_smp_processor_id(), &mask); + if (cpumask_empty(&mask)) + return; + + arm64_send_nmi(&mask); +} -- 2.7.4