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Diffstat (limited to 'arch/x86/kernel/reboot.c')
-rw-r--r--arch/x86/kernel/reboot.c126
1 files changed, 123 insertions, 3 deletions
diff --git a/arch/x86/kernel/reboot.c b/arch/x86/kernel/reboot.c
index cc5a2545dd4..61f718df6ee 100644
--- a/arch/x86/kernel/reboot.c
+++ b/arch/x86/kernel/reboot.c
@@ -21,6 +21,9 @@
# include <asm/iommu.h>
#endif
+#include <mach_ipi.h>
+
+
/*
* Power off function, if any
*/
@@ -36,7 +39,10 @@ int reboot_force;
static int reboot_cpu = -1;
#endif
-/* reboot=b[ios] | s[mp] | t[riple] | k[bd] | e[fi] [, [w]arm | [c]old]
+/* This is set by the PCI code if either type 1 or type 2 PCI is detected */
+bool port_cf9_safe = false;
+
+/* reboot=b[ios] | s[mp] | t[riple] | k[bd] | e[fi] [, [w]arm | [c]old] | p[ci]
warm Don't set the cold reboot flag
cold Set the cold reboot flag
bios Reboot by jumping through the BIOS (only for X86_32)
@@ -45,6 +51,7 @@ static int reboot_cpu = -1;
kbd Use the keyboard controller. cold reset (default)
acpi Use the RESET_REG in the FADT
efi Use efi reset_system runtime service
+ pci Use the so-called "PCI reset register", CF9
force Avoid anything that could hang.
*/
static int __init reboot_setup(char *str)
@@ -79,6 +86,7 @@ static int __init reboot_setup(char *str)
case 'k':
case 't':
case 'e':
+ case 'p':
reboot_type = *str;
break;
@@ -404,12 +412,27 @@ static void native_machine_emergency_restart(void)
reboot_type = BOOT_KBD;
break;
-
case BOOT_EFI:
if (efi_enabled)
- efi.reset_system(reboot_mode ? EFI_RESET_WARM : EFI_RESET_COLD,
+ efi.reset_system(reboot_mode ?
+ EFI_RESET_WARM :
+ EFI_RESET_COLD,
EFI_SUCCESS, 0, NULL);
+ reboot_type = BOOT_KBD;
+ break;
+ case BOOT_CF9:
+ port_cf9_safe = true;
+ /* fall through */
+
+ case BOOT_CF9_COND:
+ if (port_cf9_safe) {
+ u8 cf9 = inb(0xcf9) & ~6;
+ outb(cf9|2, 0xcf9); /* Request hard reset */
+ udelay(50);
+ outb(cf9|6, 0xcf9); /* Actually do the reset */
+ udelay(50);
+ }
reboot_type = BOOT_KBD;
break;
}
@@ -470,6 +493,11 @@ 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)
@@ -523,3 +551,95 @@ void machine_crash_shutdown(struct pt_regs *regs)
machine_ops.crash_shutdown(regs);
}
#endif
+
+
+#if defined(CONFIG_SMP)
+
+/* This keeps a track of which one is crashing cpu. */
+static int crashing_cpu;
+static nmi_shootdown_cb shootdown_callback;
+
+static atomic_t waiting_for_crash_ipi;
+
+static int crash_nmi_callback(struct notifier_block *self,
+ unsigned long val, void *data)
+{
+ int cpu;
+
+ if (val != DIE_NMI_IPI)
+ return NOTIFY_OK;
+
+ cpu = raw_smp_processor_id();
+
+ /* Don't do anything if this handler is invoked on crashing cpu.
+ * Otherwise, system will completely hang. Crashing cpu can get
+ * an NMI if system was initially booted with nmi_watchdog parameter.
+ */
+ if (cpu == crashing_cpu)
+ return NOTIFY_STOP;
+ local_irq_disable();
+
+ shootdown_callback(cpu, (struct die_args *)data);
+
+ atomic_dec(&waiting_for_crash_ipi);
+ /* Assume hlt works */
+ halt();
+ for (;;)
+ cpu_relax();
+
+ return 1;
+}
+
+static void smp_send_nmi_allbutself(void)
+{
+ cpumask_t mask = cpu_online_map;
+ cpu_clear(safe_smp_processor_id(), mask);
+ if (!cpus_empty(mask))
+ send_IPI_mask(mask, NMI_VECTOR);
+}
+
+static struct notifier_block crash_nmi_nb = {
+ .notifier_call = crash_nmi_callback,
+};
+
+/* Halt all other CPUs, calling the specified function on each of them
+ *
+ * This function can be used to halt all other CPUs on crash
+ * or emergency reboot time. The function passed as parameter
+ * will be called inside a NMI handler on all CPUs.
+ */
+void nmi_shootdown_cpus(nmi_shootdown_cb callback)
+{
+ unsigned long msecs;
+ local_irq_disable();
+
+ /* Make a note of crashing cpu. Will be used in NMI callback.*/
+ crashing_cpu = safe_smp_processor_id();
+
+ shootdown_callback = callback;
+
+ atomic_set(&waiting_for_crash_ipi, num_online_cpus() - 1);
+ /* Would it be better to replace the trap vector here? */
+ if (register_die_notifier(&crash_nmi_nb))
+ return; /* return what? */
+ /* Ensure the new callback function is set before sending
+ * out the NMI
+ */
+ wmb();
+
+ smp_send_nmi_allbutself();
+
+ msecs = 1000; /* Wait at most a second for the other cpus to stop */
+ while ((atomic_read(&waiting_for_crash_ipi) > 0) && msecs) {
+ mdelay(1);
+ msecs--;
+ }
+
+ /* Leave the nmi callback set */
+}
+#else /* !CONFIG_SMP */
+void nmi_shootdown_cpus(nmi_shootdown_cb callback)
+{
+ /* No other CPUs to shoot down */
+}
+#endif