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: Ivan Vecera <ivecera@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c
index c622772..a4da7c4 100644
--- a/arch/x86/kernel/process.c
+++ b/arch/x86/kernel/process.c
@@ -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 @@
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)
{
}