Commit d3ec5cae authored by Ivan Vecera's avatar Ivan Vecera Committed by Ingo Molnar
Browse files

x86: call machine_shutdown and stop all CPUs in native_machine_halt 



Impact: really halt all CPUs on 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?

This patch fixes it for x86.

Signed-off-by: default avatarIvan Vecera <ivecera@redhat.com>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent 3ad4f597

arch/x86/include/asm/apic.h

+1 −0
Original line number Diff line number Diff line
@@ -193,6 +193,7 @@ extern u8 setup_APIC_eilvt_ibs(u8 vector, u8 msg_type, u8 mask); 
static inline void lapic_shutdown(void) { }

#define local_apic_timer_c2_ok		1

static inline void init_apic_mappings(void) { }

static inline void disable_local_APIC(void) { }



#endif /* !CONFIG_X86_LOCAL_APIC */

arch/x86/include/asm/system.h

+2 −0
Original line number Diff line number Diff line
@@ -314,6 +314,8 @@ extern void free_init_pages(char *what, unsigned long begin, unsigned long end); 


void default_idle(void);



void stop_this_cpu(void *dummy);



/*

 * Force strict CPU ordering.

 * And yes, this is required on UP too when we're talking

arch/x86/kernel/process.c

+16 −0
Original line number Diff line number Diff line
@@ -8,6 +8,7 @@ 
#include <linux/pm.h>

#include <linux/clockchips.h>

#include <asm/system.h>

#include <asm/apic.h>



unsigned long idle_halt;

EXPORT_SYMBOL(idle_halt);
@@ -122,6 +123,21 @@ void default_idle(void) 
EXPORT_SYMBOL(default_idle);

#endif



void stop_this_cpu(void *dummy)

{

	local_irq_disable();

	/*

	 * Remove this CPU:

	 */

	cpu_clear(smp_processor_id(), cpu_online_map);

	disable_local_APIC();



	for (;;) {

		if (hlt_works(smp_processor_id()))

			halt();

	}

}



static void do_nothing(void *unused)

{

}

arch/x86/kernel/reboot.c

+5 −0
Original line number Diff line number Diff line
@@ -461,6 +461,11 @@ static void native_machine_restart(char *__unused) 


static void native_machine_halt(void)

{

	/* stop other cpus and apics */

	machine_shutdown();



	/* stop this cpu */

	stop_this_cpu(NULL);

}



static void native_machine_power_off(void)

arch/x86/kernel/smp.c

+0 −13
Original line number Diff line number Diff line
@@ -140,19 +140,6 @@ void native_send_call_func_ipi(cpumask_t mask) 
		send_IPI_mask(mask, CALL_FUNCTION_VECTOR);

}



static void stop_this_cpu(void *dummy)

{

	local_irq_disable();

	/*

	 * Remove this CPU:

	 */

	cpu_clear(smp_processor_id(), cpu_online_map);

	disable_local_APIC();

	if (hlt_works(smp_processor_id()))

		for (;;) halt();

	for (;;);

}



/*

 * this function calls the 'stop' function on all other CPUs in the system.

 */

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