From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752501AbbCSWmv (ORCPT ); Thu, 19 Mar 2015 18:42:51 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:46261 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751899AbbCSWhL (ORCPT ); Thu, 19 Mar 2015 18:37:11 -0400 From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Hemmo Nieminen , Aaro Koskinen , David Daney , linux-mips@linux-mips.org, Ralf Baechle , Kamal Mostafa Subject: [PATCH 3.13.y-ckt 68/80] MIPS: Fix kernel lockup or crash after CPU offline/online Date: Thu, 19 Mar 2015 15:35:56 -0700 Message-Id: <1426804568-2907-69-git-send-email-kamal@canonical.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1426804568-2907-1-git-send-email-kamal@canonical.com> References: <1426804568-2907-1-git-send-email-kamal@canonical.com> X-Extended-Stable: 3.13 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.13.11-ckt17 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Hemmo Nieminen commit c7754e75100ed5e3068ac5085747f2bfc386c8d6 upstream. As printk() invocation can cause e.g. a TLB miss, printk() cannot be called before the exception handlers have been properly initialized. This can happen e.g. when netconsole has been loaded as a kernel module and the TLB table has been cleared when a CPU was offline. Call cpu_report() in start_secondary() only after the exception handlers have been initialized to fix this. Without the patch the kernel will randomly either lockup or crash after a CPU is onlined and the console driver is a module. Signed-off-by: Hemmo Nieminen Signed-off-by: Aaro Koskinen Cc: David Daney Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/8953/ Signed-off-by: Ralf Baechle Signed-off-by: Kamal Mostafa --- arch/mips/kernel/smp.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/mips/kernel/smp.c b/arch/mips/kernel/smp.c index 0a022ee..18ed112 100644 --- a/arch/mips/kernel/smp.c +++ b/arch/mips/kernel/smp.c @@ -109,10 +109,10 @@ asmlinkage void start_secondary(void) else #endif /* CONFIG_MIPS_MT_SMTC */ cpu_probe(); - cpu_report(); per_cpu_trap_init(false); mips_clockevent_init(); mp_ops->init_secondary(); + cpu_report(); /* * XXX parity protection should be folded in here when it's converted -- 1.9.1