From patchwork Thu Dec 19 12:18:58 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Cristian Marussi X-Patchwork-Id: 11303385 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id C029B109A for ; Thu, 19 Dec 2019 12:21:26 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 707092068F for ; Thu, 19 Dec 2019 12:21:26 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="CqiNrJ6F" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 707092068F Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:MIME-Version:Cc:List-Subscribe: List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id:References: In-Reply-To:Message-Id:Date:Subject:To:From:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Owner; bh=LNtMitWCFQM6Y4Wdo+KHtLNYT123UIkXbrNibMhTwO4=; b=CqiNrJ6F2IaFf5BHzygzL98QM9 9Mnt4SGsXlvC3A7EwaZQzesPBhFsCrl0yien1aQ5vUawCyqAsWw3nOcC7i8htT9IFuG/Bi+3I2Rns BlCmTfYE98FuZiFukwXxURDDaRa8PWosA8SlK3RUWxjbOF0LR40m7YJ1uOvAWMzSI4uUchSb5cqUn uF5Tl1gYkJhlFj9FacKf5FCsPk4MaBMQv1wP2kBg5W0AtuVpQW6vQ06wa3YnIsSGufFMxUVJhCAfa LELTLHgeU5S/3mCz8ckbroRBWoaTqP0bcMBQyE4zb+jeWsd322jcwPmYV1DEazVJPazaCu4yOZ97l Rx3ER3tg==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1ihunz-0004k8-67; Thu, 19 Dec 2019 12:21:23 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1ihumH-0002Bd-9I for linux-arm-kernel@lists.infradead.org; Thu, 19 Dec 2019 12:19:39 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 8C441328; Thu, 19 Dec 2019 04:19:36 -0800 (PST) Received: from e120937-lin.cambridge.arm.com (e120937-lin.cambridge.arm.com [10.1.197.50]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 42B5D3F719; Thu, 19 Dec 2019 04:19:34 -0800 (PST) From: Cristian Marussi To: linux-kernel@vger.kernel.org Subject: [RFC PATCH v3 05/12] arm64: smp: use generic SMP stop common code Date: Thu, 19 Dec 2019 12:18:58 +0000 Message-Id: <20191219121905.26905-6-cristian.marussi@arm.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20191219121905.26905-1-cristian.marussi@arm.com> References: <20191219121905.26905-1-cristian.marussi@arm.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20191219_041937_444673_AC422B81 X-CRM114-Status: GOOD ( 16.07 ) X-Spam-Score: 0.0 (/) X-Spam-Report: SpamAssassin version 3.4.2 on bombadil.infradead.org summary: Content analysis details: (0.0 points) pts rule name description ---- ---------------------- -------------------------------------------------- -0.0 RCVD_IN_DNSWL_NONE RBL: Sender listed at https://www.dnswl.org/, no trust [217.140.110.172 listed in list.dnswl.org] 0.0 SPF_HELO_NONE SPF: HELO does not publish an SPF Record -0.0 SPF_PASS SPF: sender matches SPF record X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-arch@vger.kernel.org, mark.rutland@arm.com, sparclinux@vger.kernel.org, dzickus@redhat.com, ehabkost@redhat.com, peterz@infradead.org, catalin.marinas@arm.com, x86@kernel.org, linux@armlinux.org.uk, hch@infradead.org, takahiro.akashi@linaro.org, mingo@redhat.com, james.morse@arm.com, hidehiro.kawai.ez@hitachi.com, tglx@linutronix.de, will@kernel.org, davem@davemloft.net, linux-arm-kernel@lists.infradead.org MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org Make arm64 use the generic SMP-stop logic provided by common code unified smp_send_stop() function. arm64 smp_send_stop() logic had a bug in it: it failed to consider the online status of the calling CPU when evaluating if any stop message needed to be sent to other CPus at all: this resulted, on a 2-CPUs system, in the failure to stop all cpus if one paniced while starting up, leaving such system in an unexpected lively state. [root@arch ~]# echo 1 > /sys/devices/system/cpu/cpu1/online [root@arch ~]# [ 152.583368] ------------[ cut here ]------------ [ 152.583872] kernel BUG at arch/arm64/kernel/cpufeature.c:852! [ 152.584693] Internal error: Oops - BUG: 0 [#1] PREEMPT SMP [ 152.585228] Modules linked in: [ 152.586040] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.3.0-rc5-00001-gcabd12118c4a-dirty #2 [ 152.586218] Hardware name: Foundation-v8A (DT) [ 152.586478] pstate: 000001c5 (nzcv dAIF -PAN -UAO) [ 152.587260] pc : has_cpuid_feature+0x35c/0x360 [ 152.587398] lr : verify_local_elf_hwcaps+0x6c/0xf0 [ 152.587520] sp : ffff0000118bbf60 [ 152.587605] x29: ffff0000118bbf60 x28: 0000000000000000 [ 152.587784] x27: 0000000000000000 x26: 0000000000000000 [ 152.587882] x25: ffff00001167a010 x24: ffff0000112f59f8 [ 152.587992] x23: 0000000000000000 x22: 0000000000000000 [ 152.588085] x21: ffff0000112ea018 x20: ffff000010fe5518 [ 152.588180] x19: ffff000010ba3f30 x18: 0000000000000036 [ 152.588285] x17: 0000000000000000 x16: 0000000000000000 [ 152.588380] x15: 0000000000000000 x14: ffff80087a821210 [ 152.588481] x13: 0000000000000000 x12: 0000000000000000 [ 152.588599] x11: 0000000000000080 x10: 00400032b5503510 [ 152.588709] x9 : 0000000000000000 x8 : ffff000010b93204 [ 152.588810] x7 : 00000000800001d8 x6 : 0000000000000005 [ 152.588910] x5 : 0000000000000000 x4 : 0000000000000000 [ 152.589021] x3 : 0000000000000000 x2 : 0000000000008000 [ 152.589121] x1 : 0000000000180480 x0 : 0000000000180480 [ 152.589379] Call trace: [ 152.589646] has_cpuid_feature+0x35c/0x360 [ 152.589763] verify_local_elf_hwcaps+0x6c/0xf0 [ 152.589858] check_local_cpu_capabilities+0x88/0x118 [ 152.589968] secondary_start_kernel+0xc4/0x168 [ 152.590530] Code: d53801e0 17ffff58 d5380600 17ffff56 (d4210000) [ 152.592215] ---[ end trace 80ea98416149c87e ]--- [ 152.592734] Kernel panic - not syncing: Attempted to kill the idle task! [ 152.593173] Kernel Offset: disabled [ 152.593501] CPU features: 0x0004,20c02008 [ 152.593678] Memory Limit: none [ 152.594208] ---[ end Kernel panic - not syncing: Attempted to kill the idle task! ]--- [root@arch ~]# bash: echo: write error: Input/output error [root@arch ~]# [root@arch ~]# [root@arch ~]# echo HELO HELO Get rid of such bug, switching arm64 to use the common SMP stop code. Reported-by: Dave Martin Signed-off-by: Cristian Marussi --- v1 --> v2 - now selecting arch/Kconfig ARCH_USE_COMMON_SMP_STOP - added attempt_num arch_smp_stop_call() helper --- arch/arm64/Kconfig | 1 + arch/arm64/kernel/smp.c | 29 ++++++----------------------- 2 files changed, 7 insertions(+), 23 deletions(-) diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index b1b4476ddb83..618e2c2052dd 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -64,6 +64,7 @@ config ARM64 select ARCH_USE_CMPXCHG_LOCKREF select ARCH_USE_QUEUED_RWLOCKS select ARCH_USE_QUEUED_SPINLOCKS + select ARCH_USE_COMMON_SMP_STOP select ARCH_SUPPORTS_MEMORY_FAILURE select ARCH_SUPPORTS_ATOMIC_RMW select ARCH_SUPPORTS_INT128 if CC_HAS_INT128 && (GCC_VERSION >= 50000 || CC_IS_CLANG) diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c index d4ed9a19d8fe..7c1869161b5e 100644 --- a/arch/arm64/kernel/smp.c +++ b/arch/arm64/kernel/smp.c @@ -958,33 +958,16 @@ void tick_broadcast(const struct cpumask *mask) } #endif -void smp_send_stop(void) +void arch_smp_cpus_stop_complete(void) { - unsigned long timeout; - - if (num_online_cpus() > 1) { - cpumask_t mask; - - cpumask_copy(&mask, cpu_online_mask); - cpumask_clear_cpu(smp_processor_id(), &mask); - - if (system_state <= SYSTEM_RUNNING) - pr_crit("SMP: stopping secondary CPUs\n"); - smp_cross_call(&mask, IPI_CPU_STOP); - } - - /* Wait up to one second for other CPUs to stop */ - timeout = USEC_PER_SEC; - while (num_online_cpus() > 1 && timeout--) - udelay(1); - - if (num_online_cpus() > 1) - pr_warn("SMP: failed to stop secondary CPUs %*pbl\n", - cpumask_pr_args(cpu_online_mask)); - sdei_mask_local_cpu(); } +void arch_smp_stop_call(cpumask_t *cpus, unsigned int __unused) +{ + smp_cross_call(cpus, IPI_CPU_STOP); +} + #ifdef CONFIG_KEXEC_CORE void crash_smp_send_stop(void) {