Merge tag 's390-5.11-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

Pull s390 updates from Heiko Carstens:

 - Add support for the hugetlb_cma command line option to allocate
   gigantic hugepages using CMA

 - Add arch_get_random_long() support.

 - Add ap bus userspace notifications.

 - Increase default size of vmalloc area to 512GB and otherwise let it
   increase dynamically by the size of physical memory. This should fix
   all occurrences where the vmalloc area was not large enough.

 - Completely get rid of set_fs() (aka select SET_FS) and rework address
   space handling while doing that; making address space handling much
   more simple.

 - Reimplement getcpu vdso syscall in C.

 - Add support for extended SCLP responses (> 4k). This allows e.g. to
   handle also potential large system configurations.

 - Simplify KASAN by removing 3-level page table support and only
   supporting 4-levels from now on.

 - Improve debug-ability of the kernel decompressor code, which now
   prints also stack traces and symbols in case of problems to the
   console.

 - Remove more power management leftovers.

 - Other various fixes and improvements all over the place.

* tag 's390-5.11-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (62 commits)
  s390/mm: add support to allocate gigantic hugepages using CMA
  s390/crypto: add arch_get_random_long() support
  s390/smp: perform initial CPU reset also for SMT siblings
  s390/mm: use invalid asce for user space when switching to init_mm
  s390/idle: fix accounting with machine checks
  s390/idle: add missing mt_cycles calculation
  s390/boot: add build-id to decompressor
  s390/kexec_file: fix diag308 subcode when loading crash kernel
  s390/cio: fix use-after-free in ccw_device_destroy_console
  s390/cio: remove pm support from ccw bus driver
  s390/cio: remove pm support from css-bus driver
  s390/cio: remove pm support from IO subchannel drivers
  s390/cio: remove pm support from chsc subchannel driver
  s390/vmur: remove unused pm related functions
  s390/tape: remove unsupported PM functions
  s390/cio: remove pm support from eadm-sch drivers
  s390: remove pm support from console drivers
  s390/dasd: remove unused pm related functions
  s390/zfcp: remove pm support from zfcp driver
  s390/ap: let bus_register() add the AP bus sysfs attributes
  ...

68 files changed, 908 insertions, 940 deletions

diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index 4a2a12be04c9..a60cc523d810 100644
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -53,8 +53,7 @@ config ARCH_SUPPORTS_UPROBES
 config KASAN_SHADOW_OFFSET
 	hex
 	depends on KASAN
-	default 0x18000000000000 if KASAN_S390_4_LEVEL_PAGING
-	default 0x30000000000
+	default 0x18000000000000
 
 config S390
 	def_bool y
@@ -191,7 +190,6 @@ config S390
 	select PCI_DOMAINS		if PCI
 	select PCI_MSI			if PCI
 	select PCI_MSI_ARCH_FALLBACKS	if PCI_MSI
-	select SET_FS
 	select SPARSE_IRQ
 	select SYSCTL_EXCEPTION_TRACE
 	select THREAD_INFO_IN_TASK
@@ -714,7 +712,7 @@ if PCI
 config PCI_NR_FUNCTIONS
 	int "Maximum number of PCI functions (1-4096)"
 	range 1 4096
-	default "128"
+	default "512"
 	help
 	  This allows you to specify the maximum number of PCI functions which
 	  this kernel will support.
diff --git a/arch/s390/Kconfig.debug b/arch/s390/Kconfig.debug
index ab48b694ade8..6bfaceebbbc0 100644
--- a/arch/s390/Kconfig.debug
+++ b/arch/s390/Kconfig.debug
@@ -5,3 +5,11 @@ config TRACE_IRQFLAGS_SUPPORT
 
 config EARLY_PRINTK
 	def_bool y
+
+config DEBUG_USER_ASCE
+	bool "Debug User ASCE"
+	help
+	  Check on exit to user space that address space control
+	  elements are setup correctly.
+
+	  If unsure, say N.
diff --git a/arch/s390/Makefile b/arch/s390/Makefile
index ba94b03c8b2f..8db267d2a543 100644
--- a/arch/s390/Makefile
+++ b/arch/s390/Makefile
@@ -25,7 +25,7 @@ KBUILD_AFLAGS_DECOMPRESSOR := $(CLANG_FLAGS) -m64 -D__ASSEMBLY__
 KBUILD_AFLAGS_DECOMPRESSOR += $(if $(CONFIG_DEBUG_INFO),$(aflags_dwarf))
 KBUILD_CFLAGS_DECOMPRESSOR := $(CLANG_FLAGS) -m64 -O2
 KBUILD_CFLAGS_DECOMPRESSOR += -DDISABLE_BRANCH_PROFILING -D__NO_FORTIFY
-KBUILD_CFLAGS_DECOMPRESSOR += -fno-delete-null-pointer-checks -msoft-float
+KBUILD_CFLAGS_DECOMPRESSOR += -fno-delete-null-pointer-checks -msoft-float -mbackchain
 KBUILD_CFLAGS_DECOMPRESSOR += -fno-asynchronous-unwind-tables
 KBUILD_CFLAGS_DECOMPRESSOR += -ffreestanding
 KBUILD_CFLAGS_DECOMPRESSOR += $(call cc-disable-warning, address-of-packed-member)
diff --git a/arch/s390/boot/boot.h b/arch/s390/boot/boot.h
index 2ea603f70c3b..8b50967f5804 100644
--- a/arch/s390/boot/boot.h
+++ b/arch/s390/boot/boot.h
@@ -2,20 +2,32 @@
 #ifndef BOOT_BOOT_H
 #define BOOT_BOOT_H
 
+#include <linux/types.h>
+
+#define BOOT_STACK_OFFSET 0x8000
+
+#ifndef __ASSEMBLY__
+
+#include <linux/compiler.h>
+
 void startup_kernel(void);
-void detect_memory(void);
+unsigned long detect_memory(void);
+bool is_ipl_block_dump(void);
 void store_ipl_parmblock(void);
 void setup_boot_command_line(void);
 void parse_boot_command_line(void);
-void setup_memory_end(void);
 void verify_facilities(void);
 void print_missing_facilities(void);
 void print_pgm_check_info(void);
 unsigned long get_random_base(unsigned long safe_addr);
+void __printf(1, 2) decompressor_printk(const char *fmt, ...);
 
-extern int kaslr_enabled;
 extern const char kernel_version[];
+extern unsigned long memory_limit;
+extern int vmalloc_size_set;
+extern int kaslr_enabled;
 
 unsigned long read_ipl_report(unsigned long safe_offset);
 
+#endif /* __ASSEMBLY__ */
 #endif /* BOOT_BOOT_H */
diff --git a/arch/s390/boot/compressed/.gitignore b/arch/s390/boot/compressed/.gitignore
index 765a08f1bd77..01d93832cf4a 100644
--- a/arch/s390/boot/compressed/.gitignore
+++ b/arch/s390/boot/compressed/.gitignore
@@ -1,3 +1,4 @@
 # SPDX-License-Identifier: GPL-2.0-only
 vmlinux
 vmlinux.lds
+vmlinux.syms
diff --git a/arch/s390/boot/compressed/Makefile b/arch/s390/boot/compressed/Makefile
index b235ed95a3d8..de18dab518bb 100644
--- a/arch/s390/boot/compressed/Makefile
+++ b/arch/s390/boot/compressed/Makefile
@@ -10,21 +10,39 @@ GCOV_PROFILE := n
 UBSAN_SANITIZE := n
 KASAN_SANITIZE := n
 
-obj-y	:= $(if $(CONFIG_KERNEL_UNCOMPRESSED),,decompressor.o) piggy.o info.o
+obj-y	:= $(if $(CONFIG_KERNEL_UNCOMPRESSED),,decompressor.o) info.o
+obj-all := $(obj-y) piggy.o syms.o
 targets	:= vmlinux.lds vmlinux vmlinux.bin vmlinux.bin.gz vmlinux.bin.bz2
 targets += vmlinux.bin.xz vmlinux.bin.lzma vmlinux.bin.lzo vmlinux.bin.lz4
-targets += info.bin $(obj-y)
+targets += info.bin syms.bin vmlinux.syms $(obj-all)
 
 KBUILD_AFLAGS := $(KBUILD_AFLAGS_DECOMPRESSOR)
 KBUILD_CFLAGS := $(KBUILD_CFLAGS_DECOMPRESSOR)
 OBJCOPYFLAGS :=
 
 OBJECTS := $(addprefix $(obj)/,$(obj-y))
+OBJECTS_ALL := $(addprefix $(obj)/,$(obj-all))
 
-LDFLAGS_vmlinux := --oformat $(LD_BFD) -e startup -T
-$(obj)/vmlinux: $(obj)/vmlinux.lds $(objtree)/arch/s390/boot/startup.a $(OBJECTS) FORCE
+LDFLAGS_vmlinux := --oformat $(LD_BFD) -e startup --build-id=sha1 -T
+$(obj)/vmlinux: $(obj)/vmlinux.lds $(objtree)/arch/s390/boot/startup.a $(OBJECTS_ALL) FORCE
 	$(call if_changed,ld)
 
+LDFLAGS_vmlinux.syms := --oformat $(LD_BFD) -e startup -T
+$(obj)/vmlinux.syms: $(obj)/vmlinux.lds $(objtree)/arch/s390/boot/startup.a $(OBJECTS) FORCE
+	$(call if_changed,ld)
+
+quiet_cmd_dumpsyms = DUMPSYMS $<
+define cmd_dumpsyms
+	$(NM) -n -S --format=bsd "$<" | $(PERL) -ne '/(\w+)\s+(\w+)\s+[tT]\s+(\w+)/ and printf "%x %x %s\0",hex $$1,hex $$2,$$3' > "$@"
+endef
+
+$(obj)/syms.bin: $(obj)/vmlinux.syms FORCE
+	$(call if_changed,dumpsyms)
+
+OBJCOPYFLAGS_syms.o := -I binary -O elf64-s390 -B s390:64-bit --rename-section .data=.decompressor.syms
+$(obj)/syms.o: $(obj)/syms.bin FORCE
+	$(call if_changed,objcopy)
+
 OBJCOPYFLAGS_info.bin := -O binary --only-section=.vmlinux.info --set-section-flags .vmlinux.info=load
 $(obj)/info.bin: vmlinux FORCE
 	$(call if_changed,objcopy)
diff --git a/arch/s390/boot/compressed/decompressor.h b/arch/s390/boot/compressed/decompressor.h
index c15eb7114d83..41f0ad97a4db 100644
--- a/arch/s390/boot/compressed/decompressor.h
+++ b/arch/s390/boot/compressed/decompressor.h
@@ -2,8 +2,10 @@
 #ifndef BOOT_COMPRESSED_DECOMPRESSOR_H
 #define BOOT_COMPRESSED_DECOMPRESSOR_H
 
+#include <linux/stddef.h>
+
 #ifdef CONFIG_KERNEL_UNCOMPRESSED
-static inline void *decompress_kernel(void) {}
+static inline void *decompress_kernel(void) { return NULL; }
 #else
 void *decompress_kernel(void);
 #endif
diff --git a/arch/s390/boot/compressed/vmlinux.lds.S b/arch/s390/boot/compressed/vmlinux.lds.S
index 9427e2cd0c15..27a09c1c78f6 100644
--- a/arch/s390/boot/compressed/vmlinux.lds.S
+++ b/arch/s390/boot/compressed/vmlinux.lds.S
@@ -27,6 +27,7 @@ SECTIONS
 		*(.rodata.*)
 		_erodata = . ;
 	}
+	NOTES
 	.data :	{
 		_data = . ;
 		*(.data)
@@ -82,6 +83,14 @@ SECTIONS
 		*(.vmlinux.info)
 	}
 
+	.decompressor.syms : {
+		. += 1; /* make sure we have \0 before the first entry */
+		. = ALIGN(2);
+		_decompressor_syms_start = .;
+		*(.decompressor.syms)
+		_decompressor_syms_end = .;
+	}
+
 #ifdef CONFIG_KERNEL_UNCOMPRESSED
 	. = 0x100000;
 #else
diff --git a/arch/s390/boot/head.S b/arch/s390/boot/head.S
index 1a2c2b1ed964..dacb7813f982 100644
--- a/arch/s390/boot/head.S
+++ b/arch/s390/boot/head.S
@@ -28,6 +28,7 @@
 #include <asm/thread_info.h>
 #include <asm/page.h>
 #include <asm/ptrace.h>
+#include "boot.h"
 
 #define ARCH_OFFSET	4
 
@@ -62,8 +63,12 @@ __HEAD
 
 	.org	__LC_RST_NEW_PSW		# 0x1a0
 	.quad	0,iplstart
+	.org	__LC_EXT_NEW_PSW		# 0x1b0
+	.quad	0x0002000180000000,0x1b0	# disabled wait
 	.org	__LC_PGM_NEW_PSW		# 0x1d0
 	.quad	0x0000000180000000,startup_pgm_check_handler
+	.org	__LC_IO_NEW_PSW			# 0x1f0
+	.quad	0x0002000180000000,0x1f0	# disabled wait
 
 	.org	0x200
 
@@ -275,8 +280,8 @@ iplstart:
 # or linload or SALIPL
 #
 	.org	0x10000
-ENTRY(startup)
-	j	.Lep_startup_normal
+SYM_CODE_START(startup)
+	j	startup_normal
 	.org	EP_OFFSET
 #
 # This is a list of s390 kernel entry points. At address 0x1000f the number of
@@ -290,9 +295,9 @@ ENTRY(startup)
 # kdump startup-code at 0x10010, running in 64 bit absolute addressing mode
 #
 	.org	0x10010
-ENTRY(startup_kdump)
-	j	.Lep_startup_kdump
-.Lep_startup_normal:
+	j	startup_kdump
+SYM_CODE_END(startup)
+SYM_CODE_START_LOCAL(startup_normal)
 	mvi	__LC_AR_MODE_ID,1	# set esame flag
 	slr	%r0,%r0 		# set cpuid to zero
 	lhi	%r1,2			# mode 2 = esame (dump)
@@ -303,6 +308,9 @@ ENTRY(startup_kdump)
 	sam64				# switch to 64 bit addressing mode
 	basr	%r13,0			# get base
 .LPG0:
+	mvc	__LC_EXT_NEW_PSW(16),.Lext_new_psw-.LPG0(%r13)
+	mvc	__LC_PGM_NEW_PSW(16),.Lpgm_new_psw-.LPG0(%r13)
+	mvc	__LC_IO_NEW_PSW(16),.Lio_new_psw-.LPG0(%r13)
 	xc	0x200(256),0x200	# partially clear lowcore
 	xc	0x300(256),0x300
 	xc	0xe00(256),0xe00
@@ -315,12 +323,18 @@ ENTRY(startup_kdump)
 	l	%r15,.Lstack-.LPG0(%r13)
 	brasl	%r14,verify_facilities
 	brasl	%r14,startup_kernel
+SYM_CODE_END(startup_normal)
 
 .Lstack:
-	.long	0x8000 + (1<<(PAGE_SHIFT+BOOT_STACK_ORDER)) - STACK_FRAME_OVERHEAD
+	.long	BOOT_STACK_OFFSET + BOOT_STACK_SIZE - STACK_FRAME_OVERHEAD
 	.align	8
 6:	.long	0x7fffffff,0xffffffff
-
+.Lext_new_psw:
+	.quad	0x0002000180000000,0x1b0	# disabled wait
+.Lpgm_new_psw:
+	.quad	0x0000000180000000,startup_pgm_check_handler
+.Lio_new_psw:
+	.quad	0x0002000180000000,0x1f0	# disabled wait
 .Lctl:	.quad	0x04040000		# cr0: AFP registers & secondary space
 	.quad	0			# cr1: primary space segment table
 	.quad	.Lduct			# cr2: dispatchable unit control table
@@ -359,7 +373,7 @@ ENTRY(startup_kdump)
 # It simply saves general/control registers and psw in
 # the save area and does disabled wait with a faulty address.
 #
-ENTRY(startup_pgm_check_handler)
+SYM_CODE_START_LOCAL(startup_pgm_check_handler)
 	stmg	%r8,%r15,__LC_SAVE_AREA_SYNC
 	la	%r8,4095
 	stctg	%c0,%c15,__LC_CREGS_SAVE_AREA-4095(%r8)
@@ -378,9 +392,9 @@ ENTRY(startup_pgm_check_handler)
 	la	%r8,4095
 	lmg	%r0,%r15,__LC_GPREGS_SAVE_AREA-4095(%r8)
 	lpswe	__LC_RETURN_PSW		# disabled wait
+SYM_CODE_END(startup_pgm_check_handler)
 .Ldump_info_stack:
 	.long	0x5000 + PAGE_SIZE - STACK_FRAME_OVERHEAD
-ENDPROC(startup_pgm_check_handler)
 
 #
 # params at 10400 (setup.h)
diff --git a/arch/s390/boot/head_kdump.S b/arch/s390/boot/head_kdump.S
index 174d6959bf5b..f015469e7db9 100644
--- a/arch/s390/boot/head_kdump.S
+++ b/arch/s390/boot/head_kdump.S
@@ -19,8 +19,7 @@
 # Note: This code has to be position independent
 #
 
-.align 2
-.Lep_startup_kdump:
+SYM_CODE_START_LOCAL(startup_kdump)
 	lhi	%r1,2				# mode 2 = esame (dump)
 	sigp	%r1,%r0,SIGP_SET_ARCHITECTURE	# Switch to esame mode
 	sam64					# Switch to 64 bit addressing
@@ -87,14 +86,15 @@
 startup_kdump_relocated:
 	basr	%r13,0
 0:	lpswe	.Lrestart_psw-0b(%r13)		# Start new kernel...
+SYM_CODE_END(startup_kdump)
 .align	8
 .Lrestart_psw:
 	.quad	0x0000000080000000,0x0000000000000000 + startup
 #else
-.align 2
-.Lep_startup_kdump:
+SYM_CODE_START_LOCAL(startup_kdump)
 	larl	%r13,startup_kdump_crash
 	lpswe	0(%r13)
+SYM_CODE_END(startup_kdump)
 .align 8
 startup_kdump_crash:
 	.quad	0x0002000080000000,0x0000000000000000 + startup_kdump_crash
diff --git a/arch/s390/boot/ipl_parm.c b/arch/s390/boot/ipl_parm.c
index f94b91d72620..d372a45fe10e 100644
--- a/arch/s390/boot/ipl_parm.c
+++ b/arch/s390/boot/ipl_parm.c
@@ -17,10 +17,10 @@ int __bootdata_preserved(ipl_block_valid);
 unsigned int __bootdata_preserved(zlib_dfltcc_support) = ZLIB_DFLTCC_FULL;
 
 unsigned long __bootdata(vmalloc_size) = VMALLOC_DEFAULT_SIZE;
-unsigned long __bootdata(memory_end);
-int __bootdata(memory_end_set);
 int __bootdata(noexec_disabled);
 
+unsigned long memory_limit;
+int vmalloc_size_set;
 int kaslr_enabled;
 
 static inline int __diag308(unsigned long subcode, void *addr)
@@ -57,6 +57,17 @@ void store_ipl_parmblock(void)
 		ipl_block_valid = 1;
 }
 
+bool is_ipl_block_dump(void)
+{
+	if (ipl_block.pb0_hdr.pbt == IPL_PBT_FCP &&
+	    ipl_block.fcp.opt == IPL_PB0_FCP_OPT_DUMP)
+		return true;
+	if (ipl_block.pb0_hdr.pbt == IPL_PBT_NVME &&
+	    ipl_block.nvme.opt == IPL_PB0_NVME_OPT_DUMP)
+		return true;
+	return false;
+}
+
 static size_t scpdata_length(const u8 *buf, size_t count)
 {
 	while (count) {
@@ -237,13 +248,13 @@ void parse_boot_command_line(void)
 	while (*args) {
 		args = next_arg(args, &param, &val);
 
-		if (!strcmp(param, "mem") && val) {
-			memory_end = round_down(memparse(val, NULL), PAGE_SIZE);
-			memory_end_set = 1;
-		}
+		if (!strcmp(param, "mem") && val)
+			memory_limit = round_down(memparse(val, NULL), PAGE_SIZE);
 
-		if (!strcmp(param, "vmalloc") && val)
+		if (!strcmp(param, "vmalloc") && val) {
 			vmalloc_size = round_up(memparse(val, NULL), PAGE_SIZE);
+			vmalloc_size_set = 1;
+		}
 
 		if (!strcmp(param, "dfltcc") && val) {
 			if (!strcmp(val, "off"))
@@ -279,27 +290,3 @@ void parse_boot_command_line(void)
 #endif
 	}
 }
-
-static inline bool is_ipl_block_dump(void)
-{
-	if (ipl_block.pb0_hdr.pbt == IPL_PBT_FCP &&
-	    ipl_block.fcp.opt == IPL_PB0_FCP_OPT_DUMP)
-		return true;
-	if (ipl_block.pb0_hdr.pbt == IPL_PBT_NVME &&
-	    ipl_block.nvme.opt == IPL_PB0_NVME_OPT_DUMP)
-		return true;
-	return false;
-}
-
-void setup_memory_end(void)
-{
-#ifdef CONFIG_CRASH_DUMP
-	if (OLDMEM_BASE) {
-		kaslr_enabled = 0;
-	} else if (ipl_block_valid && is_ipl_block_dump()) {
-		kaslr_enabled = 0;
-		if (!sclp_early_get_hsa_size(&memory_end) && memory_end)
-			memory_end_set = 1;
-	}
-#endif
-}
diff --git a/arch/s390/boot/kaslr.c b/arch/s390/boot/kaslr.c
index d844a5ef9089..0dd48fbdbaa4 100644
--- a/arch/s390/boot/kaslr.c
+++ b/arch/s390/boot/kaslr.c
@@ -7,6 +7,7 @@
 #include <asm/cpacf.h>
 #include <asm/timex.h>
 #include <asm/sclp.h>
+#include <asm/kasan.h>
 #include "compressed/decompressor.h"
 #include "boot.h"
 
@@ -176,8 +177,14 @@ unsigned long get_random_base(unsigned long safe_addr)
 	unsigned long kasan_needs;
 	int i;
 
-	if (memory_end_set)
-		memory_limit = min(memory_limit, memory_end);
+	memory_limit = min(memory_limit, ident_map_size);
+
+	/*
+	 * Avoid putting kernel in the end of physical memory
+	 * which kasan will use for shadow memory and early pgtable
+	 * mapping allocations.
+	 */
+	memory_limit -= kasan_estimate_memory_needs(memory_limit);
 
 	if (IS_ENABLED(CONFIG_BLK_DEV_INITRD) && INITRD_START && INITRD_SIZE) {
 		if (safe_addr < INITRD_START + INITRD_SIZE)
@@ -185,28 +192,6 @@ unsigned long get_random_base(unsigned long safe_addr)
 	}
 	safe_addr = ALIGN(safe_addr, THREAD_SIZE);
 
-	if ((IS_ENABLED(CONFIG_KASAN))) {
-		/*
-		 * Estimate kasan memory requirements, which it will reserve
-		 * at the very end of available physical memory. To estimate
-		 * that, we take into account that kasan would require
-		 * 1/8 of available physical memory (for shadow memory) +
-		 * creating page tables for the whole memory + shadow memory
-		 * region (1 + 1/8). To keep page tables estimates simple take
-		 * the double of combined ptes size.
-		 */
-		memory_limit = get_mem_detect_end();
-		if (memory_end_set && memory_limit > memory_end)
-			memory_limit = memory_end;
-
-		/* for shadow memory */
-		kasan_needs = memory_limit / 8;
-		/* for paging structures */
-		kasan_needs += (memory_limit + kasan_needs) / PAGE_SIZE /
-			       _PAGE_ENTRIES * _PAGE_TABLE_SIZE * 2;
-		memory_limit -= kasan_needs;
-	}
-
 	kernel_size = vmlinux.image_size + vmlinux.bss_size;
 	if (safe_addr + kernel_size > memory_limit)
 		return 0;
diff --git a/arch/s390/boot/mem_detect.c b/arch/s390/boot/mem_detect.c
index 62e7c13ce85c..40168e59abd3 100644
--- a/arch/s390/boot/mem_detect.c
+++ b/arch/s390/boot/mem_detect.c
@@ -8,7 +8,6 @@
 #include "compressed/decompressor.h"
 #include "boot.h"
 
-unsigned long __bootdata(max_physmem_end);
 struct mem_detect_info __bootdata(mem_detect);
 
 /* up to 256 storage elements, 1020 subincrements each */
@@ -149,27 +148,29 @@ static void search_mem_end(void)
 	add_mem_detect_block(0, (offset + 1) << 20);
 }
 
-void detect_memory(void)
+unsigned long detect_memory(void)
 {
+	unsigned long max_physmem_end;
+
 	sclp_early_get_memsize(&max_physmem_end);
 
 	if (!sclp_early_read_storage_info()) {
 		mem_detect.info_source = MEM_DETECT_SCLP_STOR_INFO;
-		return;
+		return max_physmem_end;
 	}
 
 	if (!diag260()) {
 		mem_detect.info_source = MEM_DETECT_DIAG260;