[S390] Dont overwrite lowcores on smp_send_stop().

Don't perform a sigp store-status-at-address on smp_send_stop().
It will overwrite the lowcores of other cpus and destroys valueable
debug informations.

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 b05ae8584258e3f9081da0e60f2733d8fea54436..264ea906db4c1cb2b8c5258b4d448e18e9293de9 100644 (file)
--- a/arch/s390/kernel/smp.c
+++ b/arch/s390/kernel/smp.c
@@ -193,71 +193,29 @@ int smp_call_function_single(int cpu, void (*func) (void *info), void *info,
 }
 EXPORT_SYMBOL(smp_call_function_single);
 
-static void do_send_stop(void)
+void smp_send_stop(void)
 {
        int cpu, rc;
 
-       /* stop all processors */
-       for_each_online_cpu(cpu) {
-               if (cpu == smp_processor_id())
-                       continue;
-               do {
-                       rc = signal_processor(cpu, sigp_stop);
-               } while (rc == sigp_busy);
-       }
-}
+       /* Disable all interrupts/machine checks */
+       __load_psw_mask(psw_kernel_bits & ~PSW_MASK_MCHECK);
 
-static void do_store_status(void)
-{
-       int cpu, rc;
+       /* write magic number to zero page (absolute 0) */
+       lowcore_ptr[smp_processor_id()]->panic_magic = __PANIC_MAGIC;
 
-       /* store status of all processors in their lowcores (real 0) */
+       /* stop all processors */
        for_each_online_cpu(cpu) {
                if (cpu == smp_processor_id())
                        continue;
                do {
-                       rc = signal_processor_p(
-                               (__u32)(unsigned long) lowcore_ptr[cpu], cpu,
-                               sigp_store_status_at_address);
+                       rc = signal_processor(cpu, sigp_stop);
                } while (rc == sigp_busy);
-       }
-}
 
-static void do_wait_for_stop(void)
-{
-       int cpu;
-
-       /* Wait for all other cpus to enter stopped state */
-       for_each_online_cpu(cpu) {
-               if (cpu == smp_processor_id())
-                       continue;
                while (!smp_cpu_not_running(cpu))
                        cpu_relax();
        }
 }
 
-/*
- * this function sends a 'stop' sigp to all other CPUs in the system.
- * it goes straight through.
- */
-void smp_send_stop(void)
-{
-       /* Disable all interrupts/machine checks */
-       __load_psw_mask(psw_kernel_bits & ~PSW_MASK_MCHECK);
-
-       /* write magic number to zero page (absolute 0) */
-       lowcore_ptr[smp_processor_id()]->panic_magic = __PANIC_MAGIC;
-
-       /* stop other processors. */
-       do_send_stop();
-
-       /* wait until other processors are stopped */
-       do_wait_for_stop();
-
-       /* store status of other processors. */
-       do_store_status();
-}
-
 /*
  * Reboot, halt and power_off routines for SMP.
  */