linux_dsm_epyc7002/arch/s390/include/asm/smp.h
Martin Schwidefsky 00a8f886db s390/nmi: use smp_emergency_stop instead of smp_send_stop
The smp_send_stop() function can be called from s390_handle_damage
while DAT is off. This happens if a machine check indicates that
kernel gprs or control registers can not be restored. The function
smp_send_stop reenables DAT via __load_psw_mask. That should work
for the case of lost kernel gprs and the system will do the expected
stop of all CPUs. But if control registers are lost, in particular
CR13 with the home space ASCE, interesting secondary crashes may
occur.

Make smp_emergency_stop callable from nmi.c and remove the cpumask
argument. Replace the smp_send_stop call with smp_emergency_stop in
the s390_handle_damage function.

In addition add notrace and NOKPROBE_SYMBOL annotations for all
functions required for the emergency shutdown.

Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-10-19 17:07:32 +02:00

96 lines
2.4 KiB
C

/*
* Copyright IBM Corp. 1999, 2012
* Author(s): Denis Joseph Barrow,
* Martin Schwidefsky <schwidefsky@de.ibm.com>,
* Heiko Carstens <heiko.carstens@de.ibm.com>,
*/
#ifndef __ASM_SMP_H
#define __ASM_SMP_H
#include <asm/sigp.h>
#ifdef CONFIG_SMP
#include <asm/lowcore.h>
#define raw_smp_processor_id() (S390_lowcore.cpu_nr)
extern struct mutex smp_cpu_state_mutex;
extern unsigned int smp_cpu_mt_shift;
extern unsigned int smp_cpu_mtid;
extern __vector128 __initdata boot_cpu_vector_save_area[__NUM_VXRS];
extern int __cpu_up(unsigned int cpu, struct task_struct *tidle);
extern void arch_send_call_function_single_ipi(int cpu);
extern void arch_send_call_function_ipi_mask(const struct cpumask *mask);
extern void smp_call_online_cpu(void (*func)(void *), void *);
extern void smp_call_ipl_cpu(void (*func)(void *), void *);
extern void smp_emergency_stop(void);
extern int smp_find_processor_id(u16 address);
extern int smp_store_status(int cpu);
extern void smp_save_dump_cpus(void);
extern int smp_vcpu_scheduled(int cpu);
extern void smp_yield_cpu(int cpu);
extern void smp_cpu_set_polarization(int cpu, int val);
extern int smp_cpu_get_polarization(int cpu);
extern void smp_fill_possible_mask(void);
extern void smp_detect_cpus(void);
#else /* CONFIG_SMP */
#define smp_cpu_mtid 0
static inline void smp_call_ipl_cpu(void (*func)(void *), void *data)
{
func(data);
}
static inline void smp_call_online_cpu(void (*func)(void *), void *data)
{
func(data);
}
static inline void smp_emergency_stop(void)
{
}
static inline int smp_find_processor_id(u16 address) { return 0; }
static inline int smp_store_status(int cpu) { return 0; }
static inline int smp_vcpu_scheduled(int cpu) { return 1; }
static inline void smp_yield_cpu(int cpu) { }
static inline void smp_fill_possible_mask(void) { }
static inline void smp_detect_cpus(void) { }
#endif /* CONFIG_SMP */
static inline void smp_stop_cpu(void)
{
u16 pcpu = stap();
for (;;) {
__pcpu_sigp(pcpu, SIGP_STOP, 0, NULL);
cpu_relax();
}
}
/* Return thread 0 CPU number as base CPU */
static inline int smp_get_base_cpu(int cpu)
{
return cpu - (cpu % (smp_cpu_mtid + 1));
}
#ifdef CONFIG_HOTPLUG_CPU
extern int smp_rescan_cpus(void);
extern void __noreturn cpu_die(void);
extern void __cpu_die(unsigned int cpu);
extern int __cpu_disable(void);
#else
static inline int smp_rescan_cpus(void) { return 0; }
static inline void cpu_die(void) { }
#endif
#endif /* __ASM_SMP_H */