s390/kdump: fix nosmt kernel parameter
It turned out that SIGP set-multi-threading can only be done once.
Therefore switching to a different MT level after switching to
sclp.mtid_prev in the dump case fails.
As a symptom specifying the "nosmt" parameter currently fails for
the kdump kernel and the kernel starts with multi-threading enabled.
So fix this and issue diag 308 subcode 1 call after collecting the
CPU states for the dump. Also enhance the diag308_reset() function to
be usable also with enabled lowcore protection and prefix register != 0.
After the reset it is possible to switch the MT level again. We have
to do the reset very early in order not to kill the already initialized
console. Therefore instead of kmalloc() the corresponding memblock
functions have to be used. To avoid copying the sclp cpu code into
sclp_early, we now use the simple sigp loop method for CPU detection.
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/arch/s390/include/asm/ipl.h b/arch/s390/include/asm/ipl.h
index ece606c..39ae6a3 100644
--- a/arch/s390/include/asm/ipl.h
+++ b/arch/s390/include/asm/ipl.h
@@ -94,7 +94,6 @@
};
extern struct dump_save_areas dump_save_areas;
-struct save_area_ext *dump_save_area_create(int cpu);
extern void do_reipl(void);
extern void do_halt(void);
diff --git a/arch/s390/include/asm/smp.h b/arch/s390/include/asm/smp.h
index b3bd028..4098306 100644
--- a/arch/s390/include/asm/smp.h
+++ b/arch/s390/include/asm/smp.h
@@ -29,6 +29,7 @@
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);