From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1763175Ab3DCJ0I (ORCPT ); Wed, 3 Apr 2013 05:26:08 -0400 Received: from mail-da0-f42.google.com ([209.85.210.42]:43340 "EHLO mail-da0-f42.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1761264Ab3DCJ0F (ORCPT ); Wed, 3 Apr 2013 05:26:05 -0400 From: Huacai Chen To: Andrew Morton Cc: linux-kernel@vger.kernel.org, Fuxin Zhang , Huacai Chen , Subject: [PATCH] reboot: call syscore_shutdown() after disable_nonboot_cpus() Date: Wed, 3 Apr 2013 17:25:36 +0800 Message-Id: <1364981136-25629-1-git-send-email-chenhc@lemote.com> X-Mailer: git-send-email 1.7.7.3 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org As commit 40dc166c (PM / Core: Introduce struct syscore_ops for core subsystems PM) say, syscore_ops operations should be carried with one CPU on-line and interrupts disabled. However, after commit f96972f2d (kernel/sys.c: call disable_nonboot_cpus() in kernel_restart()), syscore_shutdown() is called before disable_nonboot_cpus(), so break the rules. We have a MIPS machine with a 8259A PIC, and there is an external timer (HPET) linked at 8259A. Since 8259A has been shutdown too early (by syscore_shutdown()), disable_nonboot_cpus() runs without timer interrupt, so it hangs and reboot fails. This patch call syscore_shutdown() a little later (after disable_nonboot_cpus()) to avoid reboot failure. Signed-off-by: Huacai Chen Cc: --- kernel/sys.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/kernel/sys.c b/kernel/sys.c index b0003db..f879033dd 100644 --- a/kernel/sys.c +++ b/kernel/sys.c @@ -320,7 +320,6 @@ void kernel_restart_prepare(char *cmd) system_state = SYSTEM_RESTART; usermodehelper_disable(); device_shutdown(); - syscore_shutdown(); } /** @@ -366,6 +365,7 @@ void kernel_restart(char *cmd) { kernel_restart_prepare(cmd); disable_nonboot_cpus(); + syscore_shutdown(); if (!cmd) printk(KERN_EMERG "Restarting system.\n"); else -- 1.7.7.3