[S390] smp: perform initial cpu reset before starting a cpu
Performing an initial cpu reset makes sure all registers and tlbs of
the targeted cpu are initialized and flushed.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/arch/s390/kernel/smp.c b/arch/s390/kernel/smp.c
index 1f4711b..fe5f8dc 100644
--- a/arch/s390/kernel/smp.c
+++ b/arch/s390/kernel/smp.c
@@ -534,18 +534,23 @@
struct _lowcore *cpu_lowcore;
struct stack_frame *sf;
sigp_ccode ccode;
+ u32 lowcore;
if (smp_cpu_state[cpu] != CPU_STATE_CONFIGURED)
return -EIO;
if (smp_alloc_lowcore(cpu))
return -ENOMEM;
+ do {
+ ccode = signal_processor(cpu, sigp_initial_cpu_reset);
+ if (ccode == sigp_busy)
+ udelay(10);
+ if (ccode == sigp_not_operational)
+ goto err_out;
+ } while (ccode == sigp_busy);
- ccode = signal_processor_p((__u32)(unsigned long)(lowcore_ptr[cpu]),
- cpu, sigp_set_prefix);
- if (ccode) {
- smp_free_lowcore(cpu);
- return -EIO;
- }
+ lowcore = (u32)(unsigned long)lowcore_ptr[cpu];
+ while (signal_processor_p(lowcore, cpu, sigp_set_prefix) == sigp_busy)
+ udelay(10);
idle = current_set[cpu];
cpu_lowcore = lowcore_ptr[cpu];
@@ -574,6 +579,10 @@
while (!cpu_online(cpu))
cpu_relax();
return 0;
+
+err_out:
+ smp_free_lowcore(cpu);
+ return -EIO;
}
static int __init setup_possible_cpus(char *s)