From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Message-Id: <20130507035848.487401178@goodmis.org> Date: Mon, 06 May 2013 23:57:57 -0400 From: Steven Rostedt To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Huacai Chen , "Rafael J. Wysocki" Subject: [045/126] PM / reboot: call syscore_shutdown() after disable_nonboot_cpus() References: <20130507035712.909872333@goodmis.org> Content-Disposition: inline; filename=0045-PM-reboot-call-syscore_shutdown-after-disable_nonboo.patch Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.6.11.3 stable review patch. If anyone has any objections, please let me know. ------------------ From: Huacai Chen [ Upstream commit 6f389a8f1dd22a24f3d9afc2812b30d639e94625 ] 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 Cc: Signed-off-by: Rafael J. Wysocki Signed-off-by: Steven Rostedt --- kernel/sys.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/kernel/sys.c b/kernel/sys.c index 909148a..61c086b7 100644 --- a/kernel/sys.c +++ b/kernel/sys.c @@ -323,7 +323,6 @@ void kernel_restart_prepare(char *cmd) system_state = SYSTEM_RESTART; usermodehelper_disable(); device_shutdown(); - syscore_shutdown(); } /** @@ -369,6 +368,7 @@ void kernel_restart(char *cmd) { kernel_restart_prepare(cmd); disable_nonboot_cpus(); + syscore_shutdown(); if (!cmd) printk(KERN_EMERG "Restarting system.\n"); else @@ -394,6 +394,7 @@ static void kernel_shutdown_prepare(enum system_states state) 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); -- 1.7.10.4