Adding upstream version 4.19.249.upstream/4.19.249

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 985 insertions, 0 deletions

diff --git a/arch/s390/kernel/setup.c b/arch/s390/kernel/setup.c
new file mode 100644
index 000000000..098794fc5
--- /dev/null
+++ b/arch/s390/kernel/setup.c
@@ -0,0 +1,985 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ *  S390 version
+ *    Copyright IBM Corp. 1999, 2012
+ *    Author(s): Hartmut Penner (hp@de.ibm.com),
+ *               Martin Schwidefsky (schwidefsky@de.ibm.com)
+ *
+ *  Derived from "arch/i386/kernel/setup.c"
+ *    Copyright (C) 1995, Linus Torvalds
+ */
+
+/*
+ * This file handles the architecture-dependent parts of initialization
+ */
+
+#define KMSG_COMPONENT "setup"
+#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
+
+#include <linux/errno.h>
+#include <linux/export.h>
+#include <linux/sched.h>
+#include <linux/sched/task.h>
+#include <linux/cpu.h>
+#include <linux/kernel.h>
+#include <linux/memblock.h>
+#include <linux/mm.h>
+#include <linux/stddef.h>
+#include <linux/unistd.h>
+#include <linux/ptrace.h>
+#include <linux/random.h>
+#include <linux/user.h>
+#include <linux/tty.h>
+#include <linux/ioport.h>
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/initrd.h>
+#include <linux/bootmem.h>
+#include <linux/root_dev.h>
+#include <linux/console.h>
+#include <linux/kernel_stat.h>
+#include <linux/dma-contiguous.h>
+#include <linux/device.h>
+#include <linux/notifier.h>
+#include <linux/pfn.h>
+#include <linux/ctype.h>
+#include <linux/reboot.h>
+#include <linux/topology.h>
+#include <linux/kexec.h>
+#include <linux/crash_dump.h>
+#include <linux/memory.h>
+#include <linux/compat.h>
+
+#include <asm/ipl.h>
+#include <asm/facility.h>
+#include <asm/smp.h>
+#include <asm/mmu_context.h>
+#include <asm/cpcmd.h>
+#include <asm/lowcore.h>
+#include <asm/nmi.h>
+#include <asm/irq.h>
+#include <asm/page.h>
+#include <asm/ptrace.h>
+#include <asm/sections.h>
+#include <asm/ebcdic.h>
+#include <asm/diag.h>
+#include <asm/os_info.h>
+#include <asm/sclp.h>
+#include <asm/sysinfo.h>
+#include <asm/numa.h>
+#include <asm/alternative.h>
+#include <asm/nospec-branch.h>
+#include "entry.h"
+
+/*
+ * Machine setup..
+ */
+unsigned int console_mode = 0;
+EXPORT_SYMBOL(console_mode);
+
+unsigned int console_devno = -1;
+EXPORT_SYMBOL(console_devno);
+
+unsigned int console_irq = -1;
+EXPORT_SYMBOL(console_irq);
+
+unsigned long elf_hwcap __read_mostly = 0;
+char elf_platform[ELF_PLATFORM_SIZE];
+
+unsigned long int_hwcap = 0;
+
+int __initdata memory_end_set;
+unsigned long __initdata memory_end;
+unsigned long __initdata max_physmem_end;
+
+unsigned long VMALLOC_START;
+EXPORT_SYMBOL(VMALLOC_START);
+
+unsigned long VMALLOC_END;
+EXPORT_SYMBOL(VMALLOC_END);
+
+struct page *vmemmap;
+EXPORT_SYMBOL(vmemmap);
+
+unsigned long MODULES_VADDR;
+unsigned long MODULES_END;
+
+/* An array with a pointer to the lowcore of every CPU. */
+struct lowcore *lowcore_ptr[NR_CPUS];
+EXPORT_SYMBOL(lowcore_ptr);
+
+/*
+ * This is set up by the setup-routine at boot-time
+ * for S390 need to find out, what we have to setup
+ * using address 0x10400 ...
+ */
+
+#include <asm/setup.h>
+
+/*
+ * condev= and conmode= setup parameter.
+ */
+
+static int __init condev_setup(char *str)
+{
+	int vdev;
+
+	vdev = simple_strtoul(str, &str, 0);
+	if (vdev >= 0 && vdev < 65536) {
+		console_devno = vdev;
+		console_irq = -1;
+	}
+	return 1;
+}
+
+__setup("condev=", condev_setup);
+
+static void __init set_preferred_console(void)
+{
+	if (CONSOLE_IS_3215 || CONSOLE_IS_SCLP)
+		add_preferred_console("ttyS", 0, NULL);
+	else if (CONSOLE_IS_3270)
+		add_preferred_console("tty3270", 0, NULL);
+	else if (CONSOLE_IS_VT220)
+		add_preferred_console("ttysclp", 0, NULL);
+	else if (CONSOLE_IS_HVC)
+		add_preferred_console("hvc", 0, NULL);
+}
+
+static int __init conmode_setup(char *str)
+{
+#if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
+	if (strncmp(str, "hwc", 4) == 0 || strncmp(str, "sclp", 5) == 0)
+                SET_CONSOLE_SCLP;
+#endif
+#if defined(CONFIG_TN3215_CONSOLE)
+	if (strncmp(str, "3215", 5) == 0)
+		SET_CONSOLE_3215;
+#endif
+#if defined(CONFIG_TN3270_CONSOLE)
+	if (strncmp(str, "3270", 5) == 0)
+		SET_CONSOLE_3270;
+#endif
+	set_preferred_console();
+        return 1;
+}
+
+__setup("conmode=", conmode_setup);
+
+static void __init conmode_default(void)
+{
+	char query_buffer[1024];
+	char *ptr;
+
+        if (MACHINE_IS_VM) {
+		cpcmd("QUERY CONSOLE", query_buffer, 1024, NULL);
+		console_devno = simple_strtoul(query_buffer + 5, NULL, 16);
+		ptr = strstr(query_buffer, "SUBCHANNEL =");
+		console_irq = simple_strtoul(ptr + 13, NULL, 16);
+		cpcmd("QUERY TERM", query_buffer, 1024, NULL);
+		ptr = strstr(query_buffer, "CONMODE");
+		/*
+		 * Set the conmode to 3215 so that the device recognition 
+		 * will set the cu_type of the console to 3215. If the
+		 * conmode is 3270 and we don't set it back then both
+		 * 3215 and the 3270 driver will try to access the console
+		 * device (3215 as console and 3270 as normal tty).
+		 */
+		cpcmd("TERM CONMODE 3215", NULL, 0, NULL);
+		if (ptr == NULL) {
+#if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
+			SET_CONSOLE_SCLP;
+#endif
+			return;
+		}
+		if (strncmp(ptr + 8, "3270", 4) == 0) {
+#if defined(CONFIG_TN3270_CONSOLE)
+			SET_CONSOLE_3270;
+#elif defined(CONFIG_TN3215_CONSOLE)
+			SET_CONSOLE_3215;
+#elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
+			SET_CONSOLE_SCLP;
+#endif
+		} else if (strncmp(ptr + 8, "3215", 4) == 0) {
+#if defined(CONFIG_TN3215_CONSOLE)
+			SET_CONSOLE_3215;
+#elif defined(CONFIG_TN3270_CONSOLE)
+			SET_CONSOLE_3270;
+#elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
+			SET_CONSOLE_SCLP;
+#endif
+		}
+	} else if (MACHINE_IS_KVM) {
+		if (sclp.has_vt220 && IS_ENABLED(CONFIG_SCLP_VT220_CONSOLE))
+			SET_CONSOLE_VT220;
+		else if (sclp.has_linemode && IS_ENABLED(CONFIG_SCLP_CONSOLE))
+			SET_CONSOLE_SCLP;
+		else
+			SET_CONSOLE_HVC;
+	} else {
+#if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
+		SET_CONSOLE_SCLP;
+#endif
+	}
+	if (IS_ENABLED(CONFIG_VT) && IS_ENABLED(CONFIG_DUMMY_CONSOLE))
+		conswitchp = &dummy_con;
+}
+
+#ifdef CONFIG_CRASH_DUMP
+static void __init setup_zfcpdump(void)
+{
+	if (ipl_info.type != IPL_TYPE_FCP_DUMP)
+		return;
+	if (OLDMEM_BASE)
+		return;
+	strcat(boot_command_line, " cio_ignore=all,!ipldev,!condev");
+	console_loglevel = 2;
+}
+#else
+static inline void setup_zfcpdump(void) {}
+#endif /* CONFIG_CRASH_DUMP */
+
+ /*
+ * Reboot, halt and power_off stubs. They just call _machine_restart,
+ * _machine_halt or _machine_power_off. 
+ */
+
+void machine_restart(char *command)
+{
+	if ((!in_interrupt() && !in_atomic()) || oops_in_progress)
+		/*
+		 * Only unblank the console if we are called in enabled
+		 * context or a bust_spinlocks cleared the way for us.
+		 */
+		console_unblank();
+	_machine_restart(command);
+}
+
+void machine_halt(void)
+{
+	if (!in_interrupt() || oops_in_progress)
+		/*
+		 * Only unblank the console if we are called in enabled
+		 * context or a bust_spinlocks cleared the way for us.
+		 */
+		console_unblank();
+	_machine_halt();
+}
+
+void machine_power_off(void)
+{
+	if (!in_interrupt() || oops_in_progress)
+		/*
+		 * Only unblank the console if we are called in enabled
+		 * context or a bust_spinlocks cleared the way for us.
+		 */
+		console_unblank();
+	_machine_power_off();
+}
+
+/*
+ * Dummy power off function.
+ */
+void (*pm_power_off)(void) = machine_power_off;
+EXPORT_SYMBOL_GPL(pm_power_off);
+
+static int __init early_parse_mem(char *p)
+{
+	memory_end = memparse(p, &p);
+	memory_end &= PAGE_MASK;
+	memory_end_set = 1;
+	return 0;
+}
+early_param("mem", early_parse_mem);
+
+static int __init parse_vmalloc(char *arg)
+{
+	if (!arg)
+		return -EINVAL;
+	VMALLOC_END = (memparse(arg, &arg) + PAGE_SIZE - 1) & PAGE_MASK;
+	return 0;
+}
+early_param("vmalloc", parse_vmalloc);
+
+void *restart_stack __section(.data);
+
+static void __init setup_lowcore_dat_off(void)
+{
+	struct lowcore *lc;
+
+	/*
+	 * Setup lowcore for boot cpu
+	 */
+	BUILD_BUG_ON(sizeof(struct lowcore) != LC_PAGES * PAGE_SIZE);
+	lc = memblock_virt_alloc_low(sizeof(*lc), sizeof(*lc));
+	lc->restart_psw.mask = PSW_KERNEL_BITS;
+	lc->restart_psw.addr = (unsigned long) restart_int_handler;
+	lc->external_new_psw.mask = PSW_KERNEL_BITS | PSW_MASK_MCHECK;
+	lc->external_new_psw.addr = (unsigned long) ext_int_handler;
+	lc->svc_new_psw.mask = PSW_KERNEL_BITS |
+		PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK;
+	lc->svc_new_psw.addr = (unsigned long) system_call;
+	lc->program_new_psw.mask = PSW_KERNEL_BITS | PSW_MASK_MCHECK;
+	lc->program_new_psw.addr = (unsigned long) pgm_check_handler;
+	lc->mcck_new_psw.mask = PSW_KERNEL_BITS;
+	lc->mcck_new_psw.addr = (unsigned long) mcck_int_handler;
+	lc->io_new_psw.mask = PSW_KERNEL_BITS | PSW_MASK_MCHECK;
+	lc->io_new_psw.addr = (unsigned long) io_int_handler;
+	lc->clock_comparator = clock_comparator_max;
+	lc->kernel_stack = ((unsigned long) &init_thread_union)
+		+ THREAD_SIZE - STACK_FRAME_OVERHEAD - sizeof(struct pt_regs);
+	lc->async_stack = (unsigned long)
+		memblock_virt_alloc(ASYNC_SIZE, ASYNC_SIZE)
+		+ ASYNC_SIZE - STACK_FRAME_OVERHEAD - sizeof(struct pt_regs);
+	lc->panic_stack = (unsigned long)
+		memblock_virt_alloc(PAGE_SIZE, PAGE_SIZE)
+		+ PAGE_SIZE - STACK_FRAME_OVERHEAD - sizeof(struct pt_regs);
+	lc->current_task = (unsigned long)&init_task;
+	lc->lpp = LPP_MAGIC;
+	lc->machine_flags = S390_lowcore.machine_flags;
+	lc->preempt_count = S390_lowcore.preempt_count;
+	lc->stfl_fac_list = S390_lowcore.stfl_fac_list;
+	memcpy(lc->stfle_fac_list, S390_lowcore.stfle_fac_list,
+	       sizeof(lc->stfle_fac_list));
+	memcpy(lc->alt_stfle_fac_list, S390_lowcore.alt_stfle_fac_list,
+	       sizeof(lc->alt_stfle_fac_list));
+	nmi_alloc_boot_cpu(lc);
+	vdso_alloc_boot_cpu(lc);
+	lc->sync_enter_timer = S390_lowcore.sync_enter_timer;
+	lc->async_enter_timer = S390_lowcore.async_enter_timer;
+	lc->exit_timer = S390_lowcore.exit_timer;
+	lc->user_timer = S390_lowcore.user_timer;
+	lc->system_timer = S390_lowcore.system_timer;
+	lc->steal_timer = S390_lowcore.steal_timer;
+	lc->last_update_timer = S390_lowcore.last_update_timer;
+	lc->last_update_clock = S390_lowcore.last_update_clock;
+
+	restart_stack = memblock_virt_alloc(ASYNC_SIZE, ASYNC_SIZE);
+	restart_stack += ASYNC_SIZE;
+
+	/*
+	 * Set up PSW restart to call ipl.c:do_restart(). Copy the relevant
+	 * restart data to the absolute zero lowcore. This is necessary if
+	 * PSW restart is done on an offline CPU that has lowcore zero.
+	 */
+	lc->restart_stack = (unsigned long) restart_stack;
+	lc->restart_fn = (unsigned long) do_restart;
+	lc->restart_data = 0;
+	lc->restart_source = -1UL;
+
+	/* Setup absolute zero lowcore */
+	mem_assign_absolute(S390_lowcore.restart_stack, lc->restart_stack);
+	mem_assign_absolute(S390_lowcore.restart_fn, lc->restart_fn);
+	mem_assign_absolute(S390_lowcore.restart_data, lc->restart_data);
+	mem_assign_absolute(S390_lowcore.restart_source, lc->restart_source);
+	mem_assign_absolute(S390_lowcore.restart_psw, lc->restart_psw);
+
+#ifdef CONFIG_SMP
+	lc->spinlock_lockval = arch_spin_lockval(0);
+	lc->spinlock_index = 0;
+	arch_spin_lock_setup(0);
+#endif
+	lc->br_r1_trampoline = 0x07f1;	/* br %r1 */
+
+	set_prefix((u32)(unsigned long) lc);
+	lowcore_ptr[0] = lc;
+}
+
+static void __init setup_lowcore_dat_on(void)
+{
+	__ctl_clear_bit(0, 28);
+	S390_lowcore.external_new_psw.mask |= PSW_MASK_DAT;
+	S390_lowcore.svc_new_psw.mask |= PSW_MASK_DAT;
+	S390_lowcore.program_new_psw.mask |= PSW_MASK_DAT;
+	S390_lowcore.io_new_psw.mask |= PSW_MASK_DAT;
+	__ctl_set_bit(0, 28);
+}
+
+static struct resource code_resource = {
+	.name  = "Kernel code",
+	.flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
+};
+
+static struct resource data_resource = {
+	.name = "Kernel data",
+	.flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
+};
+
+static struct resource bss_resource = {
+	.name = "Kernel bss",
+	.flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
+};
+
+static struct resource __initdata *standard_resources[] = {
+	&code_resource,
+	&data_resource,
+	&bss_resource,
+};
+
+static void __init setup_resources(void)
+{
+	struct resource *res, *std_res, *sub_res;
+	struct memblock_region *reg;
+	int j;
+
+	code_resource.start = (unsigned long) _text;
+	code_resource.end = (unsigned long) _etext - 1;
+	data_resource.start = (unsigned long) _etext;
+	data_resource.end = (unsigned long) _edata - 1;
+	bss_resource.start = (unsigned long) __bss_start;
+	bss_resource.end = (unsigned long) __bss_stop - 1;
+
+	for_each_memblock(memory, reg) {
+		res = memblock_virt_alloc(sizeof(*res), 8);
+		res->flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM;
+
+		res->name = "System RAM";
+		res->start = reg->base;
+		res->end = reg->base + reg->size - 1;
+		request_resource(&iomem_resource, res);
+
+		for (j = 0; j < ARRAY_SIZE(standard_resources); j++) {
+			std_res = standard_resources[j];
+			if (std_res->start < res->start ||
+			    std_res->start > res->end)
+				continue;
+			if (std_res->end > res->end) {
+				sub_res = memblock_virt_alloc(sizeof(*sub_res), 8);
+				*sub_res = *std_res;
+				sub_res->end = res->end;
+				std_res->start = res->end + 1;
+				request_resource(res, sub_res);
+			} else {
+				request_resource(res, std_res);
+			}
+		}
+	}
+#ifdef CONFIG_CRASH_DUMP
+	/*
+	 * Re-add removed crash kernel memory as reserved memory. This makes
+	 * sure it will be mapped with the identity mapping and struct pages
+	 * will be created, so it can be resized later on.
+	 * However add it later since the crash kernel resource should not be
+	 * part of the System RAM resource.
+	 */
+	if (crashk_res.end) {
+		memblock_add_node(crashk_res.start, resource_size(&crashk_res), 0);
+		memblock_reserve(crashk_res.start, resource_size(&crashk_res));
+		insert_resource(&iomem_resource, &crashk_res);
+	}
+#endif
+}
+
+static void __init setup_memory_end(void)
+{
+	unsigned long vmax, vmalloc_size, tmp;
+
+	/* Choose kernel address space layout: 2, 3, or 4 levels. */
+	vmalloc_size = VMALLOC_END ?: (128UL << 30) - MODULES_LEN;
+	tmp = (memory_end ?: max_physmem_end) / PAGE_SIZE;
+	tmp = tmp * (sizeof(struct page) + PAGE_SIZE);
+	if (tmp + vmalloc_size + MODULES_LEN <= _REGION2_SIZE)
+		vmax = _REGION2_SIZE; /* 3-level kernel page table */
+	else
+		vmax = _REGION1_SIZE; /* 4-level kernel page table */
+	/* module area is at the end of the kernel address space. */
+	MODULES_END = vmax;
+	MODULES_VADDR = MODULES_END - MODULES_LEN;
+	VMALLOC_END = MODULES_VADDR;
+	VMALLOC_START = vmax - vmalloc_size;
+
+	/* Split remaining virtual space between 1:1 mapping & vmemmap array */
+	tmp = VMALLOC_START / (PAGE_SIZE + sizeof(struct page));
+	/* vmemmap contains a multiple of PAGES_PER_SECTION struct pages */
+	tmp = SECTION_ALIGN_UP(tmp);
+	tmp = VMALLOC_START - tmp * sizeof(struct page);
+	tmp &= ~((vmax >> 11) - 1);	/* align to page table level */
+	tmp = min(tmp, 1UL << MAX_PHYSMEM_BITS);
+	vmemmap = (struct page *) tmp;
+
+	/* Take care that memory_end is set and <= vmemmap */
+	memory_end = min(memory_end ?: max_physmem_end, tmp);
+	max_pfn = max_low_pfn = PFN_DOWN(memory_end);
+	memblock_remove(memory_end, ULONG_MAX);
+
+	pr_notice("The maximum memory size is %luMB\n", memory_end >> 20);
+}
+
+#ifdef CONFIG_CRASH_DUMP
+
+/*
+ * When kdump is enabled, we have to ensure that no memory from
+ * the area [0 - crashkernel memory size] and
+ * [crashk_res.start - crashk_res.end] is set offline.
+ */
+static int kdump_mem_notifier(struct notifier_block *nb,
+			      unsigned long action, void *data)
+{
+	struct memory_notify *arg = data;
+
+	if (action != MEM_GOING_OFFLINE)
+		return NOTIFY_OK;
+	if (arg->start_pfn < PFN_DOWN(resource_size(&crashk_res)))
+		return NOTIFY_BAD;
+	if (arg->start_pfn > PFN_DOWN(crashk_res.end))
+		return NOTIFY_OK;
+	if (arg->start_pfn + arg->nr_pages - 1 < PFN_DOWN(crashk_res.start))
+		return NOTIFY_OK;
+	return NOTIFY_BAD;
+}
+
+static struct notifier_block kdump_mem_nb = {
+	.notifier_call = kdump_mem_notifier,
+};
+
+#endif
+
+/*
+ * Make sure that the area behind memory_end is protected
+ */
+static void __init reserve_memory_end(void)
+{
+#ifdef CONFIG_CRASH_DUMP
+	if (ipl_info.type == IPL_TYPE_FCP_DUMP &&
+	    !OLDMEM_BASE && sclp.hsa_size) {
+		memory_end = sclp.hsa_size;
+		memory_end &= PAGE_MASK;
+		memory_end_set = 1;
+	}
+#endif
+	if (!memory_end_set)
+		return;
+	memblock_reserve(memory_end, ULONG_MAX);
+}
+
+/*
+ * Make sure that oldmem, where the dump is stored, is protected
+ */
+static void __init reserve_oldmem(void)
+{
+#ifdef CONFIG_CRASH_DUMP
+	if (OLDMEM_BASE)
+		/* Forget all memory above the running kdump system */
+		memblock_reserve(OLDMEM_SIZE, (phys_addr_t)ULONG_MAX);
+#endif
+}
+
+/*
+ * Make sure that oldmem, where the dump is stored, is protected
+ */
+static void __init remove_oldmem(void)
+{
+#ifdef CONFIG_CRASH_DUMP
+	if (OLDMEM_BASE)
+		/* Forget all memory above the running kdump system */
+		memblock_remove(OLDMEM_SIZE, (phys_addr_t)ULONG_MAX);
+#endif
+}
+
+/*
+ * Reserve memory for kdump kernel to be loaded with kexec
+ */
+static void __init reserve_crashkernel(void)
+{
+#ifdef CONFIG_CRASH_DUMP
+	unsigned long long crash_base, crash_size;
+	phys_addr_t low, high;
+	int rc;
+
+	rc = parse_crashkernel(boot_command_line, memory_end, &crash_size,
+			       &crash_base);
+
+	crash_base = ALIGN(crash_base, KEXEC_CRASH_MEM_ALIGN);
+	crash_size = ALIGN(crash_size, KEXEC_CRASH_MEM_ALIGN);
+	if (rc || crash_size == 0)
+		return;
+
+	if (memblock.memory.regions[0].size < crash_size) {
+		pr_info("crashkernel reservation failed: %s\n",
+			"first memory chunk must be at least crashkernel size");
+		return;
+	}
+
+	low = crash_base ?: OLDMEM_BASE;
+	high = low + crash_size;
+	if (low >= OLDMEM_BASE && high <= OLDMEM_BASE + OLDMEM_SIZE) {
+		/* The crashkernel fits into OLDMEM, reuse OLDMEM */
+		crash_base = low;
+	} else {
+		/* Find suitable area in free memory */
+		low = max_t(unsigned long, crash_size, sclp.hsa_size);
+		high = crash_base ? crash_base + crash_size : ULONG_MAX;
+
+		if (crash_base && crash_base < low) {
+			pr_info("crashkernel reservation failed: %s\n",
+				"crash_base too low");
+			return;
+		}
+		low = crash_base ?: low;
+		crash_base = memblock_find_in_range(low, high, crash_size,
+						    KEXEC_CRASH_MEM_ALIGN);
+	}
+
+	if (!crash_base) {
+		pr_info("crashkernel reservation failed: %s\n",
+			"no suitable area found");
+		return;
+	}
+
+	if (register_memory_notifier(&kdump_mem_nb))
+		return;
+
+	if (!OLDMEM_BASE && MACHINE_IS_VM)
+		diag10_range(PFN_DOWN(crash_base), PFN_DOWN(crash_size));
+	crashk_res.start = crash_base;
+	crashk_res.end = crash_base + crash_size - 1;
+	memblock_remove(crash_base, crash_size);
+	pr_info("Reserving %lluMB of memory at %lluMB "
+		"for crashkernel (System RAM: %luMB)\n",
+		crash_size >> 20, crash_base >> 20,
+		(unsigned long)memblock.memory.total_size >> 20);
+	os_info_crashkernel_add(crash_base, crash_size);
+#endif
+}
+
+/*
+ * Reserve the initrd from being used by memblock
+ */
+static void __init reserve_initrd(void)
+{
+#ifdef CONFIG_BLK_DEV_INITRD
+	if (!INITRD_START || !INITRD_SIZE)
+		return;
+	initrd_start = INITRD_START;
+	initrd_end = initrd_start + INITRD_SIZE;
+	memblock_reserve(INITRD_START, INITRD_SIZE);
+#endif
+}
+
+/*
+ * Check for initrd being in usable memory
+ */
+static void __init check_initrd(void)
+{
+#ifdef CONFIG_BLK_DEV_INITRD
+	if (INITRD_START && INITRD_SIZE &&
+	    !memblock_is_region_memory(INITRD_START, INITRD_SIZE)) {
+		pr_err("The initial RAM disk does not fit into the memory\n");
+		memblock_free(INITRD_START, INITRD_SIZE);
+		initrd_start = initrd_end = 0;
+	}
+#endif
+}
+
+/*
+ * Reserve memory used for lowcore/command line/kernel image.
+ */
+static void __init reserve_kernel(void)
+{
+	unsigned long start_pfn = PFN_UP(__pa(_end));
+
+#ifdef CONFIG_DMA_API_DEBUG
+	/*
+	 * DMA_API_DEBUG code stumbles over addresses from the
+	 * range [PARMAREA_END, _stext]. Mark the memory as reserved
+	 * so it is not used for CONFIG_DMA_API_DEBUG=y.
+	 */
+	memblock_reserve(0, PFN_PHYS(start_pfn));
+#else
+	memblock_reserve(0, PARMAREA_END);
+	memblock_reserve((unsigned long)_stext, PFN_PHYS(start_pfn)
+			 - (unsigned long)_stext);
+#endif
+}
+
+static void __init setup_memory(void)
+{
+	struct memblock_region *reg;
+
+	/*
+	 * Init storage key for present memory
+	 */
+	for_each_memblock(memory, reg) {
+		storage_key_init_range(reg->base, reg->base + reg->size);
+	}
+	psw_set_key(PAGE_DEFAULT_KEY);
+}
+
+/*
+ * Setup hardware capabilities.
+ */
+static int __init setup_hwcaps(void)
+{
+	static const int stfl_bits[6] = { 0, 2, 7, 17, 19, 21 };
+	struct cpuid cpu_id;
+	int i;
+
+	/*
+	 * The store facility list bits numbers as found in the principles
+	 * of operation are numbered with bit 1UL<<31 as number 0 to
+	 * bit 1UL<<0 as number 31.
+	 *   Bit 0: instructions named N3, "backported" to esa-mode
+	 *   Bit 2: z/Architecture mode is active
+	 *   Bit 7: the store-facility-list-extended facility is installed
+	 *   Bit 17: the message-security assist is installed
+	 *   Bit 19: the long-displacement facility is installed
+	 *   Bit 21: the extended-immediate facility is installed
+	 *   Bit 22: extended-translation facility 3 is installed
+	 *   Bit 30: extended-translation facility 3 enhancement facility
+	 * These get translated to:
+	 *   HWCAP_S390_ESAN3 bit 0, HWCAP_S390_ZARCH bit 1,
+	 *   HWCAP_S390_STFLE bit 2, HWCAP_S390_MSA bit 3,
+	 *   HWCAP_S390_LDISP bit 4, HWCAP_S390_EIMM bit 5 and
+	 *   HWCAP_S390_ETF3EH bit 8 (22 && 30).
+	 */
+	for (i = 0; i < 6; i++)
+		if (test_facility(stfl_bits[i]))
+			elf_hwcap |= 1UL << i;
+
+	if (test_facility(22) && test_facility(30))
+		elf_hwcap |= HWCAP_S390_ETF3EH;
+
+	/*
+	 * Check for additional facilities with store-facility-list-extended.
+	 * stfle stores doublewords (8 byte) with bit 1ULL<<63 as bit 0
+	 * and 1ULL<<0 as bit 63. Bits 0-31 contain the same information
+	 * as stored by stfl, bits 32-xxx contain additional facilities.
+	 * How many facility words are stored depends on the number of
+	 * doublewords passed to the instruction. The additional facilities
+	 * are:
+	 *   Bit 42: decimal floating point facility is installed
+	 *   Bit 44: perform floating point operation facility is installed
+	 * translated to:
+	 *   HWCAP_S390_DFP bit 6 (42 && 44).
+	 */
+	if ((elf_hwcap & (1UL << 2)) && test_facility(42) && test_facility(44))
+		elf_hwcap |= HWCAP_S390_DFP;
+
+	/*
+	 * Huge page support HWCAP_S390_HPAGE is bit 7.
+	 */
+	if (MACHINE_HAS_EDAT1)
+		elf_hwcap |= HWCAP_S390_HPAGE;
+
+	/*
+	 * 64-bit register support for 31-bit processes
+	 * HWCAP_S390_HIGH_GPRS is bit 9.
+	 */
+	elf_hwcap |= HWCAP_S390_HIGH_GPRS;
+
+	/*
+	 * Transactional execution support HWCAP_S390_TE is bit 10.
+	 */
+	if (MACHINE_HAS_TE)
+		elf_hwcap |= HWCAP_S390_TE;
+
+	/*
+	 * Vector extension HWCAP_S390_VXRS is bit 11. The Vector extension
+	 * can be disabled with the "novx" parameter. Use MACHINE_HAS_VX
+	 * instead of facility bit 129.
+	 */
+	if (MACHINE_HAS_VX) {
+		elf_hwcap |= HWCAP_S390_VXRS;
+		if (test_facility(134))
+			elf_hwcap |= HWCAP_S390_VXRS_EXT;
+		if (test_facility(135))
+			elf_hwcap |= HWCAP_S390_VXRS_BCD;
+	}
+
+	/*
+	 * Guarded storage support HWCAP_S390_GS is bit 12.
+	 */
+	if (MACHINE_HAS_GS)
+		elf_hwcap |= HWCAP_S390_GS;
+
+	get_cpu_id(&cpu_id);
+	add_device_randomness(&cpu_id, sizeof(cpu_id));
+	switch (cpu_id.machine) {
+	case 0x2064:
+	case 0x2066:
+	default:	/* Use "z900" as default for 64 bit kernels. */
+		strcpy(elf_platform, "z900");
+		break;
+	case 0x2084:
+	case 0x2086:
+		strcpy(elf_platform, "z990");
+		break;
+	case 0x2094:
+	case 0x2096:
+		strcpy(elf_platform, "z9-109");
+		break;
+	case 0x2097:
+	case 0x2098:
+		strcpy(elf_platform, "z10");
+		break;
+	case 0x2817:
+	case 0x2818:
+		strcpy(elf_platform, "z196");
+		break;
+	case 0x2827:
+	case 0x2828:
+		strcpy(elf_platform, "zEC12");
+		break;
+	case 0x2964:
+	case 0x2965:
+		strcpy(elf_platform, "z13");
+		break;
+	case 0x3906:
+	case 0x3907:
+		strcpy(elf_platform, "z14");
+		break;
+	}
+
+	/*
+	 * Virtualization support HWCAP_INT_SIE is bit 0.
+	 */
+	if (sclp.has_sief2)
+		int_hwcap |= HWCAP_INT_SIE;
+
+	return 0;
+}
+arch_initcall(setup_hwcaps);
+
+/*
+ * Add system information as device randomness
+ */
+static void __init setup_randomness(void)
+{
+	struct sysinfo_3_2_2 *vmms;
+
+	vmms = (struct sysinfo_3_2_2 *) memblock_alloc(PAGE_SIZE, PAGE_SIZE);
+	if (stsi(vmms, 3, 2, 2) == 0 && vmms->count)
+		add_device_randomness(&vmms->vm, sizeof(vmms->vm[0]) * vmms->count);
+	memblock_free((unsigned long) vmms, PAGE_SIZE);
+}
+
+/*
+ * Find the correct size for the task_struct. This depends on
+ * the size of the struct fpu at the end of the thread_struct
+ * which is embedded in the task_struct.
+ */
+static void __init setup_task_size(void)
+{
+	int task_size = sizeof(struct task_struct);
+
+	if (!MACHINE_HAS_VX) {
+		task_size -= sizeof(__vector128) * __NUM_VXRS;
+		task_size += sizeof(freg_t) * __NUM_FPRS;
+	}
+	arch_task_struct_size = task_size;
+}
+
+/*
+ * Setup function called from init/main.c just after the banner
+ * was printed.
+ */
+
+void __init setup_arch(char **cmdline_p)
+{
+        /*
+         * print what head.S has found out about the machine
+         */
+	if (MACHINE_IS_VM)
+		pr_info("Linux is running as a z/VM "
+			"guest operating system in 64-bit mode\n");
+	else if (MACHINE_IS_KVM)
+		pr_info("Linux is running under KVM in 64-bit mode\n");
+	else if (MACHINE_IS_LPAR)
+		pr_info("Linux is running natively in 64-bit mode\n");
+	else
+		pr_info("Linux is running as a guest in 64-bit mode\n");
+
+	/* Have one command line that is parsed and saved in /proc/cmdline */
+	/* boot_command_line has been already set up in early.c */
+	*cmdline_p = boot_command_line;
+
+        ROOT_DEV = Root_RAM0;
+
+	/* Is init_mm really needed? */
+	init_mm.start_code = PAGE_OFFSET;
+	init_mm.end_code = (unsigned long) _etext;
+	init_mm.end_data = (unsigned long) _edata;
+	init_mm.brk = (unsigned long) _end;
+
+	if (IS_ENABLED(CONFIG_EXPOLINE_AUTO))
+		nospec_auto_detect();
+
+	parse_early_param();
+#ifdef CONFIG_CRASH_DUMP
+	/* Deactivate elfcorehdr= kernel parameter */
+	elfcorehdr_addr = ELFCORE_ADDR_MAX;
+#endif
+
+	os_info_init();
+	setup_ipl();
+	setup_task_size();
+
+	/* Do some memory reservations *before* memory is added to memblock */
+	reserve_memory_end();
+	reserve_oldmem();
+	reserve_kernel();
+	reserve_initrd();
+	memblock_allow_resize();
+
+	/* Get information about *all* installed memory */
+	detect_memory_memblock();
+
+	remove_oldmem();
+
+	/*
+	 * Make sure all chunks are MAX_ORDER aligned so we don't need the
+	 * extra checks that HOLES_IN_ZONE would require.
+	 *
+	 * Is this still required?
+	 */
+	memblock_trim_memory(1UL << (MAX_ORDER - 1 + PAGE_SHIFT));
+
+	setup_memory_end();
+	setup_memory();
+	dma_contiguous_reserve(memory_end);
+	vmcp_cma_reserve();
+
+	check_initrd();
+	reserve_crashkernel();
+#ifdef CONFIG_CRASH_DUMP
+	/*
+	 * Be aware that smp_save_dump_cpus() triggers a system reset.
+	 * Therefore CPU and device initialization should be done afterwards.
+	 */
+	smp_save_dump_cpus();
+#endif
+
+	setup_resources();
+	setup_lowcore_dat_off();
+	smp_fill_possible_mask();
+	cpu_detect_mhz_feature();
+        cpu_init();
+	numa_setup();
+	smp_detect_cpus();
+	topology_init_early();
+
+	/*
+	 * Create kernel page tables and switch to virtual addressing.
+	 */
+        paging_init();
+
+	/*
+	 * After paging_init created the kernel page table, the new PSWs
+	 * in lowcore can now run with DAT enabled.
+	 */
+	setup_lowcore_dat_on();
+
+        /* Setup default console */
+	conmode_default();
+	set_preferred_console();
+
+	apply_alternative_instructions();
+	if (IS_ENABLED(CONFIG_EXPOLINE))
+		nospec_init_branches();
+
+	/* Setup zfcpdump support */
+	setup_zfcpdump();
+
+	/* Add system specific data to the random pool */
+	setup_randomness();
+}