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-rw-r--r--arch/s390/kernel/setup.c1197
1 files changed, 1197 insertions, 0 deletions
diff --git a/arch/s390/kernel/setup.c b/arch/s390/kernel/setup.c
new file mode 100644
index 000000000..520cf5a15
--- /dev/null
+++ b/arch/s390/kernel/setup.c
@@ -0,0 +1,1197 @@
+// 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/root_dev.h>
+#include <linux/console.h>
+#include <linux/kernel_stat.h>
+#include <linux/dma-map-ops.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 <linux/start_kernel.h>
+
+#include <asm/boot_data.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/stacktrace.h>
+#include <asm/sysinfo.h>
+#include <asm/numa.h>
+#include <asm/alternative.h>
+#include <asm/nospec-branch.h>
+#include <asm/mem_detect.h>
+#include <asm/uv.h>
+#include <asm/asm-offsets.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 __bootdata(noexec_disabled);
+int __bootdata(memory_end_set);
+unsigned long __bootdata(memory_end);
+unsigned long __bootdata(vmalloc_size);
+unsigned long __bootdata(max_physmem_end);
+struct mem_detect_info __bootdata(mem_detect);
+
+struct exception_table_entry *__bootdata_preserved(__start_dma_ex_table);
+struct exception_table_entry *__bootdata_preserved(__stop_dma_ex_table);
+unsigned long __bootdata_preserved(__stext_dma);
+unsigned long __bootdata_preserved(__etext_dma);
+unsigned long __bootdata_preserved(__sdma);
+unsigned long __bootdata_preserved(__edma);
+unsigned long __bootdata_preserved(__kaslr_offset);
+unsigned int __bootdata_preserved(zlib_dfltcc_support);
+EXPORT_SYMBOL(zlib_dfltcc_support);
+
+unsigned long VMALLOC_START;
+EXPORT_SYMBOL(VMALLOC_START);
+
+unsigned long VMALLOC_END;
+EXPORT_SYMBOL(VMALLOC_END);
+
+struct page *vmemmap;
+EXPORT_SYMBOL(vmemmap);
+unsigned long vmemmap_size;
+
+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);
+
+/*
+ * The Write Back bit position in the physaddr is given by the SLPC PCI.
+ * Leaving the mask zero always uses write through which is safe
+ */
+unsigned long mio_wb_bit_mask __ro_after_init;
+
+/*
+ * 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 (!strcmp(str, "hwc") || !strcmp(str, "sclp"))
+ SET_CONSOLE_SCLP;
+#endif
+#if defined(CONFIG_TN3215_CONSOLE)
+ if (!strcmp(str, "3215"))
+ SET_CONSOLE_3215;
+#endif
+#if defined(CONFIG_TN3270_CONSOLE)
+ if (!strcmp(str, "3270"))
+ 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 (str_has_prefix(ptr + 8, "3270")) {
+#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 (str_has_prefix(ptr + 8, "3215")) {
+#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
+ }
+}
+
+#ifdef CONFIG_CRASH_DUMP
+static void __init setup_zfcpdump(void)
+{
+ if (!is_ipl_type_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);
+
+void *restart_stack;
+
+unsigned long stack_alloc(void)
+{
+#ifdef CONFIG_VMAP_STACK
+ return (unsigned long)__vmalloc_node(THREAD_SIZE, THREAD_SIZE,
+ THREADINFO_GFP, NUMA_NO_NODE,
+ __builtin_return_address(0));
+#else
+ return __get_free_pages(GFP_KERNEL, THREAD_SIZE_ORDER);
+#endif
+}
+
+void stack_free(unsigned long stack)
+{
+#ifdef CONFIG_VMAP_STACK
+ vfree((void *) stack);
+#else
+ free_pages(stack, THREAD_SIZE_ORDER);
+#endif
+}
+
+int __init arch_early_irq_init(void)
+{
+ unsigned long stack;
+
+ stack = __get_free_pages(GFP_KERNEL, THREAD_SIZE_ORDER);
+ if (!stack)
+ panic("Couldn't allocate async stack");
+ S390_lowcore.async_stack = stack + STACK_INIT_OFFSET;
+ return 0;
+}
+
+static int __init async_stack_realloc(void)
+{
+ unsigned long old, new;
+
+ old = S390_lowcore.async_stack - STACK_INIT_OFFSET;
+ new = stack_alloc();
+ if (!new)
+ panic("Couldn't allocate async stack");
+ S390_lowcore.async_stack = new + STACK_INIT_OFFSET;
+ free_pages(old, THREAD_SIZE_ORDER);
+ return 0;
+}
+early_initcall(async_stack_realloc);
+
+void __init arch_call_rest_init(void)
+{
+ unsigned long stack;
+
+ stack = stack_alloc();
+ if (!stack)
+ panic("Couldn't allocate kernel stack");
+ current->stack = (void *) stack;
+#ifdef CONFIG_VMAP_STACK
+ current->stack_vm_area = (void *) stack;
+#endif
+ set_task_stack_end_magic(current);
+ stack += STACK_INIT_OFFSET;
+ S390_lowcore.kernel_stack = stack;
+ CALL_ON_STACK_NORETURN(rest_init, stack);
+}
+
+static void __init setup_lowcore_dat_off(void)
+{
+ unsigned long int_psw_mask = PSW_KERNEL_BITS;
+ struct lowcore *lc;
+
+ if (IS_ENABLED(CONFIG_KASAN))
+ int_psw_mask |= PSW_MASK_DAT;
+
+ /*
+ * Setup lowcore for boot cpu
+ */
+ BUILD_BUG_ON(sizeof(struct lowcore) != LC_PAGES * PAGE_SIZE);
+ lc = memblock_alloc_low(sizeof(*lc), sizeof(*lc));
+ if (!lc)
+ panic("%s: Failed to allocate %zu bytes align=%zx\n",
+ __func__, 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 = int_psw_mask | PSW_MASK_MCHECK;
+ lc->external_new_psw.addr = (unsigned long) ext_int_handler;
+ lc->svc_new_psw.mask = int_psw_mask | PSW_MASK_MCHECK;
+ lc->svc_new_psw.addr = (unsigned long) system_call;
+ lc->program_new_psw.mask = int_psw_mask | 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 = int_psw_mask | PSW_MASK_MCHECK;
+ lc->io_new_psw.addr = (unsigned long) io_int_handler;
+ lc->clock_comparator = clock_comparator_max;
+ lc->nodat_stack = ((unsigned long) &init_thread_union)
+ + THREAD_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);
+ 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;
+
+ /*
+ * Allocate the global restart stack which is the same for
+ * all CPUs in cast *one* of them does a PSW restart.
+ */
+ restart_stack = memblock_alloc(THREAD_SIZE, THREAD_SIZE);
+ if (!restart_stack)
+ panic("%s: Failed to allocate %lu bytes align=0x%lx\n",
+ __func__, THREAD_SIZE, THREAD_SIZE);
+ restart_stack += STACK_INIT_OFFSET;
+
+ /*
+ * 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);
+
+ lc->spinlock_lockval = arch_spin_lockval(0);
+ lc->spinlock_index = 0;
+ arch_spin_lock_setup(0);
+ lc->br_r1_trampoline = 0x07f1; /* br %r1 */
+ lc->return_lpswe = gen_lpswe(__LC_RETURN_PSW);
+ lc->return_mcck_lpswe = gen_lpswe(__LC_RETURN_MCCK_PSW);
+ lc->preempt_count = PREEMPT_DISABLED;
+
+ 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;
+ phys_addr_t start, end;
+ int j;
+ u64 i;
+
+ 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_mem_range(i, &start, &end) {
+ res = memblock_alloc(sizeof(*res), 8);
+ if (!res)
+ panic("%s: Failed to allocate %zu bytes align=0x%x\n",
+ __func__, sizeof(*res), 8);
+ res->flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM;
+
+ res->name = "System RAM";
+ res->start = start;
+ /*
+ * In memblock, end points to the first byte after the
+ * range while in resourses, end points to the last byte in
+ * the range.
+ */
+ res->end = end - 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_alloc(sizeof(*sub_res), 8);
+ if (!sub_res)
+ panic("%s: Failed to allocate %zu bytes align=0x%x\n",
+ __func__, 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, tmp;
+
+ /* Choose kernel address space layout: 3 or 4 levels. */
+ 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 */
+ if (is_prot_virt_host())
+ adjust_to_uv_max(&vmax);
+#ifdef CONFIG_KASAN
+ vmax = kasan_vmax;
+#endif
+ /* 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 = VMALLOC_END - 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, (unsigned long)vmemmap);
+#ifdef CONFIG_KASAN
+ memory_end = min(memory_end, KASAN_SHADOW_START);
+#endif
+ vmemmap_size = SECTION_ALIGN_UP(memory_end / PAGE_SIZE) * sizeof(struct page);
+#ifdef CONFIG_KASAN
+ /* move vmemmap above kasan shadow only if stands in a way */
+ if (KASAN_SHADOW_END > (unsigned long)vmemmap &&
+ (unsigned long)vmemmap + vmemmap_size > KASAN_SHADOW_START)
+ vmemmap = max(vmemmap, (struct page *)KASAN_SHADOW_END);
+#endif
+ 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] is set offline - it will be exchanged with
+ * the crashkernel memory region when kdump is triggered. The crashkernel
+ * memory region can never get offlined (pages are unmovable).
+ */
+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;
+ return NOTIFY_OK;
+}
+
+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)
+{
+ if (memory_end_set)
+ 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
+}
+
+/*
+ * Reserve the memory area used to pass the certificate lists
+ */
+static void __init reserve_certificate_list(void)
+{
+ if (ipl_cert_list_addr)
+ memblock_reserve(ipl_cert_list_addr, ipl_cert_list_size);
+}
+
+static void __init reserve_mem_detect_info(void)
+{
+ unsigned long start, size;
+
+ get_mem_detect_reserved(&start, &size);
+ if (size)
+ memblock_reserve(start, size);
+}
+
+static void __init free_mem_detect_info(void)
+{
+ unsigned long start, size;
+
+ get_mem_detect_reserved(&start, &size);
+ if (size)
+ memblock_free(start, size);
+}
+
+static const char * __init get_mem_info_source(void)
+{
+ switch (mem_detect.info_source) {
+ case MEM_DETECT_SCLP_STOR_INFO:
+ return "sclp storage info";
+ case MEM_DETECT_DIAG260:
+ return "diag260";
+ case MEM_DETECT_SCLP_READ_INFO:
+ return "sclp read info";
+ case MEM_DETECT_BIN_SEARCH:
+ return "binary search";
+ }
+ return "none";
+}
+
+static void __init memblock_add_mem_detect_info(void)
+{
+ unsigned long start, end;
+ int i;
+
+ pr_debug("physmem info source: %s (%hhd)\n",
+ get_mem_info_source(), mem_detect.info_source);
+ /* keep memblock lists close to the kernel */
+ memblock_set_bottom_up(true);
+ for_each_mem_detect_block(i, &start, &end) {
+ memblock_add(start, end - start);
+ memblock_physmem_add(start, end - start);
+ }
+ memblock_set_bottom_up(false);
+ memblock_set_node(0, ULONG_MAX, &memblock.memory, 0);
+ memblock_dump_all();
+}
+
+/*
+ * 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));
+
+ memblock_reserve(0, HEAD_END);
+ memblock_reserve((unsigned long)_stext, PFN_PHYS(start_pfn)
+ - (unsigned long)_stext);
+ memblock_reserve(__sdma, __edma - __sdma);
+}
+
+static void __init setup_memory(void)
+{
+ phys_addr_t start, end;
+ u64 i;
+
+ /*
+ * Init storage key for present memory
+ */
+ for_each_mem_range(i, &start, &end)
+ storage_key_init_range(start, end);
+
+ 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_BCD;
+ if (test_facility(135))
+ elf_hwcap |= HWCAP_S390_VXRS_EXT;
+ if (test_facility(148))
+ elf_hwcap |= HWCAP_S390_VXRS_EXT2;
+ if (test_facility(152))
+ elf_hwcap |= HWCAP_S390_VXRS_PDE;
+ }
+ if (test_facility(150))
+ elf_hwcap |= HWCAP_S390_SORT;
+ if (test_facility(151))
+ elf_hwcap |= HWCAP_S390_DFLT;
+
+ /*
+ * 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;
+ case 0x8561:
+ case 0x8562:
+ strcpy(elf_platform, "z15");
+ 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_phys_alloc(PAGE_SIZE,
+ PAGE_SIZE);
+ if (!vmms)
+ panic("Failed to allocate memory for sysinfo structure\n");
+
+ 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);
+
+#ifdef CONFIG_ARCH_RANDOM
+ if (cpacf_query_func(CPACF_PRNO, CPACF_PRNO_TRNG))
+ static_branch_enable(&s390_arch_random_available);
+#endif
+}
+
+/*
+ * 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;
+}
+
+/*
+ * Issue diagnose 318 to set the control program name and
+ * version codes.
+ */
+static void __init setup_control_program_code(void)
+{
+ union diag318_info diag318_info = {
+ .cpnc = CPNC_LINUX,
+ .cpvc = 0,
+ };
+
+ if (!sclp.has_diag318)
+ return;
+
+ diag_stat_inc(DIAG_STAT_X318);
+ asm volatile("diag %0,0,0x318\n" : : "d" (diag318_info.val));
+}
+
+/*
+ * Print the component list from the IPL report
+ */
+static void __init log_component_list(void)
+{
+ struct ipl_rb_component_entry *ptr, *end;
+ char *str;
+
+ if (!early_ipl_comp_list_addr)
+ return;
+ if (ipl_block.hdr.flags & IPL_PL_FLAG_SIPL)
+ pr_info("Linux is running with Secure-IPL enabled\n");
+ else
+ pr_info("Linux is running with Secure-IPL disabled\n");
+ ptr = (void *) early_ipl_comp_list_addr;
+ end = (void *) ptr + early_ipl_comp_list_size;
+ pr_info("The IPL report contains the following components:\n");
+ while (ptr < end) {
+ if (ptr->flags & IPL_RB_COMPONENT_FLAG_SIGNED) {
+ if (ptr->flags & IPL_RB_COMPONENT_FLAG_VERIFIED)
+ str = "signed, verified";
+ else
+ str = "signed, verification failed";
+ } else {
+ str = "not signed";
+ }
+ pr_info("%016llx - %016llx (%s)\n",
+ ptr->addr, ptr->addr + ptr->len, str);
+ ptr++;
+ }
+}
+
+/*
+ * 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");
+
+ log_component_list();
+
+ /* 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;
+
+ init_mm.start_code = (unsigned long) _text;
+ 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();
+
+ jump_label_init();
+ 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();
+ setup_control_program_code();
+
+ /* Do some memory reservations *before* memory is added to memblock */
+ reserve_memory_end();
+ reserve_oldmem();
+ reserve_kernel();
+ reserve_initrd();
+ reserve_certificate_list();
+ reserve_mem_detect_info();
+ memblock_allow_resize();
+
+ /* Get information about *all* installed memory */
+ memblock_add_mem_detect_info();
+
+ free_mem_detect_info();
+ remove_oldmem();
+
+ setup_uv();
+ 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 zfcp/nvme dump support */
+ setup_zfcpdump();
+
+ /* Add system specific data to the random pool */
+ setup_randomness();
+}