diff --git a/arch/powerpc/kernel/head_64.S b/arch/powerpc/kernel/head_64.S index b24b7001ae19cb5c39651b4fb510afc54288a88f..bed9a29ee383a067ba6e2a37a1b74385e746ad13 100644 --- a/arch/powerpc/kernel/head_64.S +++ b/arch/powerpc/kernel/head_64.S @@ -617,6 +617,17 @@ _GLOBAL(start_secondary_prolog) std r3,0(r1) /* Zero the stack frame pointer */ bl .start_secondary b . +/* + * Reset stack pointer and call start_secondary + * to continue with online operation when woken up + * from cede in cpu offline. + */ +_GLOBAL(start_secondary_resume) + ld r1,PACAKSAVE(r13) /* Reload kernel stack pointer */ + li r3,0 + std r3,0(r1) /* Zero the stack frame pointer */ + bl .start_secondary + b . #endif /* diff --git a/arch/powerpc/platforms/pseries/hotplug-cpu.c b/arch/powerpc/platforms/pseries/hotplug-cpu.c index d1b124e44d7701204c688d1a12df57d15d6f62e1..349e0af9389ac4dd651c7301e1d961cc2e89257e 100644 --- a/arch/powerpc/platforms/pseries/hotplug-cpu.c +++ b/arch/powerpc/platforms/pseries/hotplug-cpu.c @@ -146,12 +146,11 @@ static void pseries_mach_cpu_die(void) unregister_slb_shadow(hwcpu, __pa(get_slb_shadow())); /* - * NOTE: Calling start_secondary() here for now to - * start new context. - * However, need to do it cleanly by resetting the - * stack pointer. + * Call to start_secondary_resume() will not return. + * Kernel stack will be reset and start_secondary() + * will be called to continue the online operation. */ - start_secondary(); + start_secondary_resume(); } else if (get_preferred_offline_state(cpu) == CPU_STATE_OFFLINE) { diff --git a/arch/powerpc/platforms/pseries/offline_states.h b/arch/powerpc/platforms/pseries/offline_states.h index 202d8692c6a2e06d746c047e106da4f92797deb0..75a6f480d931da5f298afc1618008857d0a7a5b6 100644 --- a/arch/powerpc/platforms/pseries/offline_states.h +++ b/arch/powerpc/platforms/pseries/offline_states.h @@ -35,4 +35,5 @@ static inline void set_default_offline_state(int cpu) extern enum cpu_state_vals get_preferred_offline_state(int cpu); extern int start_secondary(void); +extern void start_secondary_resume(void); #endif