linux-kernel - [PATCH] x86: call machine_shutdown and stop all CPUs in native_machine

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Date:	Mon, 20 Oct 2008 14:13:07 +0200
From:	Ivan Vecera <ivecera@...hat.com>
To:	linux-kernel@...r.kernel.org
Cc:	tglx@...utronix.de, mingo@...hat.com, hpa@...or.com,
	nhorman@...hat.com, jmarchan@...hat.com,
	Ivan Vecera <ivecera@...hat.com>
Subject: [PATCH] x86: call machine_shutdown and stop all CPUs in native_machine_halt

Function machine_halt (resp. native_machine_halt) is empty for x86
architectures. When command 'halt -f' is invoked, the message
"System halted." is displayed but this is not really true because
all CPUs are still running.
There are also similar inconsistencies for other arches (some uses
power-off for halt or forever-loop with IRQs enabled/disabled).
IMO there should be used the same approach for all architectures
OR what does the message "System halted" really mean?

Signed-off-by: Ivan Vecera <ivecera@...hat.com>
---
 arch/x86/kernel/reboot.c |    8 ++++++++
 1 files changed, 8 insertions(+), 0 deletions(-)

diff --git a/arch/x86/kernel/reboot.c b/arch/x86/kernel/reboot.c
index f4c93f1..15ad949 100644
--- a/arch/x86/kernel/reboot.c
+++ b/arch/x86/kernel/reboot.c
@@ -465,6 +465,14 @@ static void native_machine_restart(char *__unused)
 
 static void native_machine_halt(void)
 {
+	/* stop other cpus and apics */
+	machine_shutdown();
+
+	/* stop this cpu */
+	local_irq_disable();
+	if (hlt_works(smp_processor_id()))
+		for (;;) halt();
+	for (;;);
 }
 
 static void native_machine_power_off(void)
-- 
1.5.6.3

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