i386/x86-64: x86 nmi fix From: Shaohua Li Making NMI suspend/resume work with SMP. We use CPU hotplug to offline APs in SMP suspend/resume. Only BSP executes sysdev's .suspend/.resume method. APs should follow CPU hotplug code path. Signed-off-by: Shaohua Li Signed-off-by: Andi Kleen Cc: Don Zickus Cc: Andi Kleen Signed-off-by: Andrew Morton --- arch/i386/kernel/nmi.c | 14 +++++++++----- arch/i386/kernel/smpboot.c | 3 ++- arch/x86_64/kernel/nmi.c | 14 +++++++++----- arch/x86_64/kernel/smpboot.c | 2 ++ include/asm-i386/nmi.h | 1 + include/asm-x86_64/nmi.h | 1 + 6 files changed, 24 insertions(+), 11 deletions(-) Index: linux/arch/i386/kernel/nmi.c =================================================================== --- linux.orig/arch/i386/kernel/nmi.c +++ linux/arch/i386/kernel/nmi.c @@ -63,7 +63,6 @@ struct nmi_watchdog_ctlblk { static DEFINE_PER_CPU(struct nmi_watchdog_ctlblk, nmi_watchdog_ctlblk); /* local prototypes */ -static void stop_apic_nmi_watchdog(void *unused); static int unknown_nmi_panic_callback(struct pt_regs *regs, int cpu); extern void show_registers(struct pt_regs *regs); @@ -341,15 +340,20 @@ static int nmi_pm_active; /* nmi_active static int lapic_nmi_suspend(struct sys_device *dev, pm_message_t state) { + /* only CPU0 goes here, other CPUs should be offline */ nmi_pm_active = atomic_read(&nmi_active); - disable_lapic_nmi_watchdog(); + stop_apic_nmi_watchdog(NULL); + BUG_ON(atomic_read(&nmi_active) != 0); return 0; } static int lapic_nmi_resume(struct sys_device *dev) { - if (nmi_pm_active > 0) - enable_lapic_nmi_watchdog(); + /* only CPU0 goes here, other CPUs should be offline */ + if (nmi_pm_active > 0) { + setup_apic_nmi_watchdog(NULL); + touch_nmi_watchdog(); + } return 0; } @@ -667,7 +671,7 @@ void setup_apic_nmi_watchdog (void *unus atomic_inc(&nmi_active); } -static void stop_apic_nmi_watchdog(void *unused) +void stop_apic_nmi_watchdog(void *unused) { /* only support LOCAL and IO APICs for now */ if ((nmi_watchdog != NMI_LOCAL_APIC) && Index: linux/arch/i386/kernel/smpboot.c =================================================================== --- linux.orig/arch/i386/kernel/smpboot.c +++ linux/arch/i386/kernel/smpboot.c @@ -1372,7 +1372,8 @@ int __cpu_disable(void) */ if (cpu == 0) return -EBUSY; - + if (nmi_watchdog == NMI_LOCAL_APIC) + stop_apic_nmi_watchdog(NULL); clear_local_APIC(); /* Allow any queued timer interrupts to get serviced */ local_irq_enable(); Index: linux/arch/x86_64/kernel/nmi.c =================================================================== --- linux.orig/arch/x86_64/kernel/nmi.c +++ linux/arch/x86_64/kernel/nmi.c @@ -63,7 +63,6 @@ struct nmi_watchdog_ctlblk { static DEFINE_PER_CPU(struct nmi_watchdog_ctlblk, nmi_watchdog_ctlblk); /* local prototypes */ -static void stop_apic_nmi_watchdog(void *unused); static int unknown_nmi_panic_callback(struct pt_regs *regs, int cpu); /* converts an msr to an appropriate reservation bit */ @@ -337,15 +336,20 @@ static int nmi_pm_active; /* nmi_active static int lapic_nmi_suspend(struct sys_device *dev, pm_message_t state) { + /* only CPU0 goes here, other CPUs should be offline */ nmi_pm_active = atomic_read(&nmi_active); - disable_lapic_nmi_watchdog(); + stop_apic_nmi_watchdog(NULL); + BUG_ON(atomic_read(&nmi_active) != 0); return 0; } static int lapic_nmi_resume(struct sys_device *dev) { - if (nmi_pm_active > 0) - enable_lapic_nmi_watchdog(); + /* only CPU0 goes here, other CPUs should be offline */ + if (nmi_pm_active > 0) { + setup_apic_nmi_watchdog(NULL); + touch_nmi_watchdog(); + } return 0; } @@ -586,7 +590,7 @@ void setup_apic_nmi_watchdog(void *unuse atomic_inc(&nmi_active); } -static void stop_apic_nmi_watchdog(void *unused) +void stop_apic_nmi_watchdog(void *unused) { /* only support LOCAL and IO APICs for now */ if ((nmi_watchdog != NMI_LOCAL_APIC) && Index: linux/arch/x86_64/kernel/smpboot.c =================================================================== --- linux.orig/arch/x86_64/kernel/smpboot.c +++ linux/arch/x86_64/kernel/smpboot.c @@ -1233,6 +1233,8 @@ int __cpu_disable(void) if (cpu == 0) return -EBUSY; + if (nmi_watchdog == NMI_LOCAL_APIC) + stop_apic_nmi_watchdog(NULL); clear_local_APIC(); /* Index: linux/include/asm-i386/nmi.h =================================================================== --- linux.orig/include/asm-i386/nmi.h +++ linux/include/asm-i386/nmi.h @@ -23,6 +23,7 @@ extern int reserve_evntsel_nmi(unsigned extern void release_evntsel_nmi(unsigned int); extern void setup_apic_nmi_watchdog (void *); +extern void stop_apic_nmi_watchdog (void *); extern void disable_timer_nmi_watchdog(void); extern void enable_timer_nmi_watchdog(void); extern int nmi_watchdog_tick (struct pt_regs * regs, unsigned reason); Index: linux/include/asm-x86_64/nmi.h =================================================================== --- linux.orig/include/asm-x86_64/nmi.h +++ linux/include/asm-x86_64/nmi.h @@ -54,6 +54,7 @@ extern int reserve_evntsel_nmi(unsigned extern void release_evntsel_nmi(unsigned int); extern void setup_apic_nmi_watchdog (void *); +extern void stop_apic_nmi_watchdog (void *); extern void disable_timer_nmi_watchdog(void); extern void enable_timer_nmi_watchdog(void); extern int nmi_watchdog_tick (struct pt_regs * regs, unsigned reason);