From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755275Ab3DVOfD (ORCPT ); Mon, 22 Apr 2013 10:35:03 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:51639 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755039Ab3DVOaU (ORCPT ); Mon, 22 Apr 2013 10:30:20 -0400 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Rafael J. Wysocki" , "Huacai Chen" Date: Mon, 22 Apr 2013 15:25:59 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [29/75] PM / reboot: call syscore_shutdown() after disable_nonboot_cpus() In-Reply-To: X-SA-Exim-Connect-IP: 2001:470:1f08:1539:6834:ff73:7553:7f84 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.2.44-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Huacai Chen commit 6f389a8f1dd22a24f3d9afc2812b30d639e94625 upstream. 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, this is the same way as poweroff does. For consistency, add disable_nonboot_cpus() to kernel_halt(). Signed-off-by: Huacai Chen Signed-off-by: Rafael J. Wysocki Signed-off-by: Ben Hutchings --- kernel/sys.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- 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 @@ -391,6 +391,7 @@ static void kernel_shutdown_prepare(enum void kernel_halt(void) { kernel_shutdown_prepare(SYSTEM_HALT); + disable_nonboot_cpus(); syscore_shutdown(); printk(KERN_EMERG "System halted.\n"); kmsg_dump(KMSG_DUMP_HALT);