s390/smp: fix smp_stop_cpu() for !CONFIG_SMP
smp_stop_cpu() should stop the current cpu even for !CONFIG_SMP.
Otherwise machine_halt() will return and and the machine generates a
panic instread of simply stopping the current cpu:
Kernel panic - not syncing: Attempted to kill init! exitcode=0x00000000
CPU: 0 PID: 1 Comm: systemd-shutdow Not tainted 3.14.0-01527-g2b6ef16a6bc5 #10
[...]
Call Trace:
([<0000000000110db0>] show_trace+0xf8/0x158)
[<0000000000110e7a>] show_stack+0x6a/0xe8
[<000000000074dba8>] panic+0xe4/0x268
[<0000000000140570>] do_exit+0xa88/0xb2c
[<000000000016e12c>] SyS_reboot+0x1f0/0x234
[<000000000075da70>] sysc_nr_ok+0x22/0x28
[<000000007d5a09b4>] 0x7d5a09b4
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/arch/s390/include/asm/sigp.h b/arch/s390/include/asm/sigp.h
index d091aa1..bf9c823 100644
--- a/arch/s390/include/asm/sigp.h
+++ b/arch/s390/include/asm/sigp.h
@@ -31,4 +31,23 @@
#define SIGP_STATUS_INCORRECT_STATE 0x00000200UL
#define SIGP_STATUS_NOT_RUNNING 0x00000400UL
+#ifndef __ASSEMBLY__
+
+static inline int __pcpu_sigp(u16 addr, u8 order, u32 parm, u32 *status)
+{
+ register unsigned int reg1 asm ("1") = parm;
+ int cc;
+
+ asm volatile(
+ " sigp %1,%2,0(%3)\n"
+ " ipm %0\n"
+ " srl %0,28\n"
+ : "=d" (cc), "+d" (reg1) : "d" (addr), "a" (order) : "cc");
+ if (status && cc == 1)
+ *status = reg1;
+ return cc;
+}
+
+#endif /* __ASSEMBLY__ */
+
#endif /* __S390_ASM_SIGP_H */