[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>

1 files changed, 16 insertions, 7 deletions

diff --git a/arch/s390/kernel/smp.c b/arch/s390/kernel/smp.c
index 1f4711b60aab..fe5f8dc1e6fa 100644
--- a/arch/s390/kernel/smp.c
+++ b/arch/s390/kernel/smp.c
@@ -534,18 +534,23 @@ int __cpuinit __cpu_up(unsigned int cpu)
         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;
-
-        ccode = signal_processor_p((__u32)(unsigned long)(lowcore_ptr[cpu]),
-                                   cpu, sigp_set_prefix);
-        if (ccode) {
-                smp_free_lowcore(cpu);
-                return -EIO;
-        }
+        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);
+
+        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 @@ int __cpuinit __cpu_up(unsigned int cpu)
         while (!cpu_online(cpu))
                 cpu_relax();
         return 0;
+
+err_out:
+        smp_free_lowcore(cpu);
+        return -EIO;
 }
 
 static int __init setup_possible_cpus(char *s)