arch/s390/kernel/setup.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *  S390 version
   4  *    Copyright IBM Corp. 1999, 2012
   5  *    Author(s): Hartmut Penner ([email protected]),
   6  *               Martin Schwidefsky ([email protected])
   7  *
   8  *  Derived from "arch/i386/kernel/setup.c"
   9  *    Copyright (C) 1995, Linus Torvalds
  10  */
  11
  12 /*
  13  * This file handles the architecture-dependent parts of initialization
  14  */
  15
  16 #define KMSG_COMPONENT "setup"
  17 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
  18
  19 #include <linux/errno.h>
  20 #include <linux/export.h>
  21 #include <linux/sched.h>
  22 #include <linux/sched/task.h>
  23 #include <linux/cpu.h>
  24 #include <linux/kernel.h>
  25 #include <linux/memblock.h>
  26 #include <linux/mm.h>
  27 #include <linux/stddef.h>
  28 #include <linux/unistd.h>
  29 #include <linux/ptrace.h>
  30 #include <linux/random.h>
  31 #include <linux/user.h>
  32 #include <linux/tty.h>
  33 #include <linux/ioport.h>
  34 #include <linux/delay.h>
  35 #include <linux/init.h>
  36 #include <linux/initrd.h>
  37 #include <linux/root_dev.h>
  38 #include <linux/console.h>
  39 #include <linux/kernel_stat.h>
  40 #include <linux/dma-map-ops.h>
  41 #include <linux/device.h>
  42 #include <linux/notifier.h>
  43 #include <linux/pfn.h>
  44 #include <linux/ctype.h>
  45 #include <linux/reboot.h>
  46 #include <linux/topology.h>
  47 #include <linux/kexec.h>
  48 #include <linux/crash_dump.h>
  49 #include <linux/memory.h>
  50 #include <linux/compat.h>
  51 #include <linux/start_kernel.h>
  52 #include <linux/hugetlb.h>
  53 #include <linux/kmemleak.h>
  54
  55 #include <asm/archrandom.h>
  56 #include <asm/boot_data.h>
  57 #include <asm/ipl.h>
  58 #include <asm/facility.h>
  59 #include <asm/smp.h>
  60 #include <asm/mmu_context.h>
  61 #include <asm/cpcmd.h>
  62 #include <asm/abs_lowcore.h>
  63 #include <asm/nmi.h>
  64 #include <asm/irq.h>
  65 #include <asm/page.h>
  66 #include <asm/ptrace.h>
  67 #include <asm/sections.h>
  68 #include <asm/ebcdic.h>
  69 #include <asm/diag.h>
  70 #include <asm/os_info.h>
  71 #include <asm/sclp.h>
  72 #include <asm/stacktrace.h>
  73 #include <asm/sysinfo.h>
  74 #include <asm/numa.h>
  75 #include <asm/alternative.h>
  76 #include <asm/nospec-branch.h>
  77 #include <asm/mem_detect.h>
  78 #include <asm/maccess.h>
  79 #include <asm/uv.h>
  80 #include <asm/asm-offsets.h>
  81 #include "entry.h"
  82
  83 /*
  84  * Machine setup..
  85  */
  86 unsigned int console_mode = 0;
  87 EXPORT_SYMBOL(console_mode);
  88
  89 unsigned int console_devno = -1;
  90 EXPORT_SYMBOL(console_devno);
  91
  92 unsigned int console_irq = -1;
  93 EXPORT_SYMBOL(console_irq);
  94
  95 /*
  96  * Some code and data needs to stay below 2 GB, even when the kernel would be
  97  * relocated above 2 GB, because it has to use 31 bit addresses.
  98  * Such code and data is part of the .amode31 section.
  99  */
 100 unsigned long __amode31_ref __samode31 = (unsigned long)&_samode31;
 101 unsigned long __amode31_ref __eamode31 = (unsigned long)&_eamode31;
 102 unsigned long __amode31_ref __stext_amode31 = (unsigned long)&_stext_amode31;
 103 unsigned long __amode31_ref __etext_amode31 = (unsigned long)&_etext_amode31;
 104 struct exception_table_entry __amode31_ref *__start_amode31_ex_table = _start_amode31_ex_table;
 105 struct exception_table_entry __amode31_ref *__stop_amode31_ex_table = _stop_amode31_ex_table;
 106
 107 /*
 108  * Control registers CR2, CR5 and CR15 are initialized with addresses
 109  * of tables that must be placed below 2G which is handled by the AMODE31
 110  * sections.
 111  * Because the AMODE31 sections are relocated below 2G at startup,
 112  * the content of control registers CR2, CR5 and CR15 must be updated
 113  * with new addresses after the relocation. The initial initialization of
 114  * control registers occurs in head64.S and then gets updated again after AMODE31
 115  * relocation. We must access the relevant AMODE31 tables indirectly via
 116  * pointers placed in the .amode31.refs linker section. Those pointers get
 117  * updated automatically during AMODE31 relocation and always contain a valid
 118  * address within AMODE31 sections.
 119  */
 120
 121 static __amode31_data u32 __ctl_duct_amode31[16] __aligned(64);
 122
 123 static __amode31_data u64 __ctl_aste_amode31[8] __aligned(64) = {
 124         [1] = 0xffffffffffffffff
 125 };
 126
 127 static __amode31_data u32 __ctl_duald_amode31[32] __aligned(128) = {
 128         0x80000000, 0, 0, 0,
 129         0x80000000, 0, 0, 0,
 130         0x80000000, 0, 0, 0,
 131         0x80000000, 0, 0, 0,
 132         0x80000000, 0, 0, 0,
 133         0x80000000, 0, 0, 0,
 134         0x80000000, 0, 0, 0,
 135         0x80000000, 0, 0, 0
 136 };
 137
 138 static __amode31_data u32 __ctl_linkage_stack_amode31[8] __aligned(64) = {
 139         0, 0, 0x89000000, 0,
 140         0, 0, 0x8a000000, 0
 141 };
 142
 143 static u64 __amode31_ref *__ctl_aste = __ctl_aste_amode31;
 144 static u32 __amode31_ref *__ctl_duald = __ctl_duald_amode31;
 145 static u32 __amode31_ref *__ctl_linkage_stack = __ctl_linkage_stack_amode31;
 146 static u32 __amode31_ref *__ctl_duct = __ctl_duct_amode31;
 147
 148 int __bootdata(noexec_disabled);
 149 unsigned long __bootdata(ident_map_size);
 150 struct mem_detect_info __bootdata(mem_detect);
 151 struct initrd_data __bootdata(initrd_data);
 152
 153 unsigned long __bootdata_preserved(__kaslr_offset);
 154 unsigned long __bootdata(__amode31_base);
 155 unsigned int __bootdata_preserved(zlib_dfltcc_support);
 156 EXPORT_SYMBOL(zlib_dfltcc_support);
 157 u64 __bootdata_preserved(stfle_fac_list[16]);
 158 EXPORT_SYMBOL(stfle_fac_list);
 159 u64 __bootdata_preserved(alt_stfle_fac_list[16]);
 160 struct oldmem_data __bootdata_preserved(oldmem_data);
 161
 162 unsigned long VMALLOC_START;
 163 EXPORT_SYMBOL(VMALLOC_START);
 164
 165 unsigned long VMALLOC_END;
 166 EXPORT_SYMBOL(VMALLOC_END);
 167
 168 struct page *vmemmap;
 169 EXPORT_SYMBOL(vmemmap);
 170 unsigned long vmemmap_size;
 171
 172 unsigned long MODULES_VADDR;
 173 unsigned long MODULES_END;
 174
 175 /* An array with a pointer to the lowcore of every CPU. */
 176 struct lowcore *lowcore_ptr[NR_CPUS];
 177 EXPORT_SYMBOL(lowcore_ptr);
 178
 179 DEFINE_STATIC_KEY_FALSE(cpu_has_bear);
 180
 181 /*
 182  * The Write Back bit position in the physaddr is given by the SLPC PCI.
 183  * Leaving the mask zero always uses write through which is safe
 184  */
 185 unsigned long mio_wb_bit_mask __ro_after_init;
 186
 187 /*
 188  * This is set up by the setup-routine at boot-time
 189  * for S390 need to find out, what we have to setup
 190  * using address 0x10400 ...
 191  */
 192
 193 #include <asm/setup.h>
 194
 195 /*
 196  * condev= and conmode= setup parameter.
 197  */
 198
 199 static int __init condev_setup(char *str)
 200 {
 201         int vdev;
 202
 203         vdev = simple_strtoul(str, &str, 0);
 204         if (vdev >= 0 && vdev < 65536) {
 205                 console_devno = vdev;
 206                 console_irq = -1;
 207         }
 208         return 1;
 209 }
 210
 211 __setup("condev=", condev_setup);
 212
 213 static void __init set_preferred_console(void)
 214 {
 215         if (CONSOLE_IS_3215 || CONSOLE_IS_SCLP)
 216                 add_preferred_console("ttyS", 0, NULL);
 217         else if (CONSOLE_IS_3270)
 218                 add_preferred_console("tty3270", 0, NULL);
 219         else if (CONSOLE_IS_VT220)
 220                 add_preferred_console("ttysclp", 0, NULL);
 221         else if (CONSOLE_IS_HVC)
 222                 add_preferred_console("hvc", 0, NULL);
 223 }
 224
 225 static int __init conmode_setup(char *str)
 226 {
 227 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 228         if (!strcmp(str, "hwc") || !strcmp(str, "sclp"))
 229                 SET_CONSOLE_SCLP;
 230 #endif
 231 #if defined(CONFIG_TN3215_CONSOLE)
 232         if (!strcmp(str, "3215"))
 233                 SET_CONSOLE_3215;
 234 #endif
 235 #if defined(CONFIG_TN3270_CONSOLE)
 236         if (!strcmp(str, "3270"))
 237                 SET_CONSOLE_3270;
 238 #endif
 239         set_preferred_console();
 240         return 1;
 241 }
 242
 243 __setup("conmode=", conmode_setup);
 244
 245 static void __init conmode_default(void)
 246 {
 247         char query_buffer[1024];
 248         char *ptr;
 249
 250         if (MACHINE_IS_VM) {
 251                 cpcmd("QUERY CONSOLE", query_buffer, 1024, NULL);
 252                 console_devno = simple_strtoul(query_buffer + 5, NULL, 16);
 253                 ptr = strstr(query_buffer, "SUBCHANNEL =");
 254                 console_irq = simple_strtoul(ptr + 13, NULL, 16);
 255                 cpcmd("QUERY TERM", query_buffer, 1024, NULL);
 256                 ptr = strstr(query_buffer, "CONMODE");
 257                 /*
 258                  * Set the conmode to 3215 so that the device recognition
 259                  * will set the cu_type of the console to 3215. If the
 260                  * conmode is 3270 and we don't set it back then both
 261                  * 3215 and the 3270 driver will try to access the console
 262                  * device (3215 as console and 3270 as normal tty).
 263                  */
 264                 cpcmd("TERM CONMODE 3215", NULL, 0, NULL);
 265                 if (ptr == NULL) {
 266 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 267                         SET_CONSOLE_SCLP;
 268 #endif
 269                         return;
 270                 }
 271                 if (str_has_prefix(ptr + 8, "3270")) {
 272 #if defined(CONFIG_TN3270_CONSOLE)
 273                         SET_CONSOLE_3270;
 274 #elif defined(CONFIG_TN3215_CONSOLE)
 275                         SET_CONSOLE_3215;
 276 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 277                         SET_CONSOLE_SCLP;
 278 #endif
 279                 } else if (str_has_prefix(ptr + 8, "3215")) {
 280 #if defined(CONFIG_TN3215_CONSOLE)
 281                         SET_CONSOLE_3215;
 282 #elif defined(CONFIG_TN3270_CONSOLE)
 283                         SET_CONSOLE_3270;
 284 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 285                         SET_CONSOLE_SCLP;
 286 #endif
 287                 }
 288         } else if (MACHINE_IS_KVM) {
 289                 if (sclp.has_vt220 && IS_ENABLED(CONFIG_SCLP_VT220_CONSOLE))
 290                         SET_CONSOLE_VT220;
 291                 else if (sclp.has_linemode && IS_ENABLED(CONFIG_SCLP_CONSOLE))
 292                         SET_CONSOLE_SCLP;
 293                 else
 294                         SET_CONSOLE_HVC;
 295         } else {
 296 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 297                 SET_CONSOLE_SCLP;
 298 #endif
 299         }
 300 }
 301
 302 #ifdef CONFIG_CRASH_DUMP
 303 static void __init setup_zfcpdump(void)
 304 {
 305         if (!is_ipl_type_dump())
 306                 return;
 307         if (oldmem_data.start)
 308                 return;
 309         strcat(boot_command_line, " cio_ignore=all,!ipldev,!condev");
 310         console_loglevel = 2;
 311 }
 312 #else
 313 static inline void setup_zfcpdump(void) {}
 314 #endif /* CONFIG_CRASH_DUMP */
 315
 316  /*
 317  * Reboot, halt and power_off stubs. They just call _machine_restart,
 318  * _machine_halt or _machine_power_off.
 319  */
 320
 321 void machine_restart(char *command)
 322 {
 323         if ((!in_interrupt() && !in_atomic()) || oops_in_progress)
 324                 /*
 325                  * Only unblank the console if we are called in enabled
 326                  * context or a bust_spinlocks cleared the way for us.
 327                  */
 328                 console_unblank();
 329         _machine_restart(command);
 330 }
 331
 332 void machine_halt(void)
 333 {
 334         if (!in_interrupt() || oops_in_progress)
 335                 /*
 336                  * Only unblank the console if we are called in enabled
 337                  * context or a bust_spinlocks cleared the way for us.
 338                  */
 339                 console_unblank();
 340         _machine_halt();
 341 }
 342
 343 void machine_power_off(void)
 344 {
 345         if (!in_interrupt() || oops_in_progress)
 346                 /*
 347                  * Only unblank the console if we are called in enabled
 348                  * context or a bust_spinlocks cleared the way for us.
 349                  */
 350                 console_unblank();
 351         _machine_power_off();
 352 }
 353
 354 /*
 355  * Dummy power off function.
 356  */
 357 void (*pm_power_off)(void) = machine_power_off;
 358 EXPORT_SYMBOL_GPL(pm_power_off);
 359
 360 void *restart_stack;
 361
 362 unsigned long stack_alloc(void)
 363 {
 364 #ifdef CONFIG_VMAP_STACK
 365         void *ret;
 366
 367         ret = __vmalloc_node(THREAD_SIZE, THREAD_SIZE, THREADINFO_GFP,
 368                              NUMA_NO_NODE, __builtin_return_address(0));
 369         kmemleak_not_leak(ret);
 370         return (unsigned long)ret;
 371 #else
 372         return __get_free_pages(GFP_KERNEL, THREAD_SIZE_ORDER);
 373 #endif
 374 }
 375
 376 void stack_free(unsigned long stack)
 377 {
 378 #ifdef CONFIG_VMAP_STACK
 379         vfree((void *) stack);
 380 #else
 381         free_pages(stack, THREAD_SIZE_ORDER);
 382 #endif
 383 }
 384
 385 int __init arch_early_irq_init(void)
 386 {
 387         unsigned long stack;
 388
 389         stack = __get_free_pages(GFP_KERNEL, THREAD_SIZE_ORDER);
 390         if (!stack)
 391                 panic("Couldn't allocate async stack");
 392         S390_lowcore.async_stack = stack + STACK_INIT_OFFSET;
 393         return 0;
 394 }
 395
 396 void __init arch_call_rest_init(void)
 397 {
 398         unsigned long stack;
 399
 400         smp_reinit_ipl_cpu();
 401         stack = stack_alloc();
 402         if (!stack)
 403                 panic("Couldn't allocate kernel stack");
 404         current->stack = (void *) stack;
 405 #ifdef CONFIG_VMAP_STACK
 406         current->stack_vm_area = (void *) stack;
 407 #endif
 408         set_task_stack_end_magic(current);
 409         stack += STACK_INIT_OFFSET;
 410         S390_lowcore.kernel_stack = stack;
 411         call_on_stack_noreturn(rest_init, stack);
 412 }
 413
 414 static void __init setup_lowcore_dat_off(void)
 415 {
 416         unsigned long int_psw_mask = PSW_KERNEL_BITS;
 417         struct lowcore *abs_lc, *lc;
 418         unsigned long mcck_stack;
 419         unsigned long flags;
 420
 421         if (IS_ENABLED(CONFIG_KASAN))
 422                 int_psw_mask |= PSW_MASK_DAT;
 423
 424         /*
 425          * Setup lowcore for boot cpu
 426          */
 427         BUILD_BUG_ON(sizeof(struct lowcore) != LC_PAGES * PAGE_SIZE);
 428         lc = memblock_alloc_low(sizeof(*lc), sizeof(*lc));
 429         if (!lc)
 430                 panic("%s: Failed to allocate %zu bytes align=%zx\n",
 431                       __func__, sizeof(*lc), sizeof(*lc));
 432
 433         lc->restart_psw.mask = PSW_KERNEL_BITS;
 434         lc->restart_psw.addr = (unsigned long) restart_int_handler;
 435         lc->external_new_psw.mask = int_psw_mask | PSW_MASK_MCHECK;
 436         lc->external_new_psw.addr = (unsigned long) ext_int_handler;
 437         lc->svc_new_psw.mask = int_psw_mask | PSW_MASK_MCHECK;
 438         lc->svc_new_psw.addr = (unsigned long) system_call;
 439         lc->program_new_psw.mask = int_psw_mask | PSW_MASK_MCHECK;
 440         lc->program_new_psw.addr = (unsigned long) pgm_check_handler;
 441         lc->mcck_new_psw.mask = int_psw_mask;
 442         lc->mcck_new_psw.addr = (unsigned long) mcck_int_handler;
 443         lc->io_new_psw.mask = int_psw_mask | PSW_MASK_MCHECK;
 444         lc->io_new_psw.addr = (unsigned long) io_int_handler;
 445         lc->clock_comparator = clock_comparator_max;
 446         lc->nodat_stack = ((unsigned long) &init_thread_union)
 447                 + THREAD_SIZE - STACK_FRAME_OVERHEAD - sizeof(struct pt_regs);
 448         lc->current_task = (unsigned long)&init_task;
 449         lc->lpp = LPP_MAGIC;
 450         lc->machine_flags = S390_lowcore.machine_flags;
 451         lc->preempt_count = S390_lowcore.preempt_count;
 452         nmi_alloc_mcesa_early(&lc->mcesad);
 453         lc->sys_enter_timer = S390_lowcore.sys_enter_timer;
 454         lc->exit_timer = S390_lowcore.exit_timer;
 455         lc->user_timer = S390_lowcore.user_timer;
 456         lc->system_timer = S390_lowcore.system_timer;
 457         lc->steal_timer = S390_lowcore.steal_timer;
 458         lc->last_update_timer = S390_lowcore.last_update_timer;
 459         lc->last_update_clock = S390_lowcore.last_update_clock;
 460
 461         /*
 462          * Allocate the global restart stack which is the same for
 463          * all CPUs in cast *one* of them does a PSW restart.
 464          */
 465         restart_stack = memblock_alloc(THREAD_SIZE, THREAD_SIZE);
 466         if (!restart_stack)
 467                 panic("%s: Failed to allocate %lu bytes align=0x%lx\n",
 468                       __func__, THREAD_SIZE, THREAD_SIZE);
 469         restart_stack += STACK_INIT_OFFSET;
 470
 471         /*
 472          * Set up PSW restart to call ipl.c:do_restart(). Copy the relevant
 473          * restart data to the absolute zero lowcore. This is necessary if
 474          * PSW restart is done on an offline CPU that has lowcore zero.
 475          */
 476         lc->restart_stack = (unsigned long) restart_stack;
 477         lc->restart_fn = (unsigned long) do_restart;
 478         lc->restart_data = 0;
 479         lc->restart_source = -1U;
 480
 481         abs_lc = get_abs_lowcore(&flags);
 482         abs_lc->restart_stack = lc->restart_stack;
 483         abs_lc->restart_fn = lc->restart_fn;
 484         abs_lc->restart_data = lc->restart_data;
 485         abs_lc->restart_source = lc->restart_source;
 486         abs_lc->restart_psw = lc->restart_psw;
 487         abs_lc->mcesad = lc->mcesad;
 488         put_abs_lowcore(abs_lc, flags);
 489
 490         mcck_stack = (unsigned long)memblock_alloc(THREAD_SIZE, THREAD_SIZE);
 491         if (!mcck_stack)
 492                 panic("%s: Failed to allocate %lu bytes align=0x%lx\n",
 493                       __func__, THREAD_SIZE, THREAD_SIZE);
 494         lc->mcck_stack = mcck_stack + STACK_INIT_OFFSET;
 495
 496         lc->spinlock_lockval = arch_spin_lockval(0);
 497         lc->spinlock_index = 0;
 498         arch_spin_lock_setup(0);
 499         lc->return_lpswe = gen_lpswe(__LC_RETURN_PSW);
 500         lc->return_mcck_lpswe = gen_lpswe(__LC_RETURN_MCCK_PSW);
 501         lc->preempt_count = PREEMPT_DISABLED;
 502
 503         set_prefix(__pa(lc));
 504         lowcore_ptr[0] = lc;
 505 }
 506
 507 static void __init setup_lowcore_dat_on(void)
 508 {
 509         struct lowcore *abs_lc;
 510         unsigned long flags;
 511
 512         __ctl_clear_bit(0, 28);
 513         S390_lowcore.external_new_psw.mask |= PSW_MASK_DAT;
 514         S390_lowcore.svc_new_psw.mask |= PSW_MASK_DAT;
 515         S390_lowcore.program_new_psw.mask |= PSW_MASK_DAT;
 516         S390_lowcore.mcck_new_psw.mask |= PSW_MASK_DAT;
 517         S390_lowcore.io_new_psw.mask |= PSW_MASK_DAT;
 518         __ctl_set_bit(0, 28);
 519         __ctl_store(S390_lowcore.cregs_save_area, 0, 15);
 520         if (abs_lowcore_map(0, lowcore_ptr[0], true))
 521                 panic("Couldn't setup absolute lowcore");
 522         abs_lowcore_mapped = true;
 523         abs_lc = get_abs_lowcore(&flags);
 524         abs_lc->restart_flags = RESTART_FLAG_CTLREGS;
 525         abs_lc->program_new_psw = S390_lowcore.program_new_psw;
 526         memcpy(abs_lc->cregs_save_area, S390_lowcore.cregs_save_area,
 527                sizeof(abs_lc->cregs_save_area));
 528         put_abs_lowcore(abs_lc, flags);
 529 }
 530
 531 static struct resource code_resource = {
 532         .name  = "Kernel code",
 533         .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
 534 };
 535
 536 static struct resource data_resource = {
 537         .name = "Kernel data",
 538         .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
 539 };
 540
 541 static struct resource bss_resource = {
 542         .name = "Kernel bss",
 543         .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
 544 };
 545
 546 static struct resource __initdata *standard_resources[] = {
 547         &code_resource,
 548         &data_resource,
 549         &bss_resource,
 550 };
 551
 552 static void __init setup_resources(void)
 553 {
 554         struct resource *res, *std_res, *sub_res;
 555         phys_addr_t start, end;
 556         int j;
 557         u64 i;
 558
 559         code_resource.start = (unsigned long) _text;
 560         code_resource.end = (unsigned long) _etext - 1;
 561         data_resource.start = (unsigned long) _etext;
 562         data_resource.end = (unsigned long) _edata - 1;
 563         bss_resource.start = (unsigned long) __bss_start;
 564         bss_resource.end = (unsigned long) __bss_stop - 1;
 565
 566         for_each_mem_range(i, &start, &end) {
 567                 res = memblock_alloc(sizeof(*res), 8);
 568                 if (!res)
 569                         panic("%s: Failed to allocate %zu bytes align=0x%x\n",
 570                               __func__, sizeof(*res), 8);
 571                 res->flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM;
 572
 573                 res->name = "System RAM";
 574                 res->start = start;
 575                 /*
 576                  * In memblock, end points to the first byte after the
 577                  * range while in resourses, end points to the last byte in
 578                  * the range.
 579                  */
 580                 res->end = end - 1;
 581                 request_resource(&iomem_resource, res);
 582
 583                 for (j = 0; j < ARRAY_SIZE(standard_resources); j++) {
 584                         std_res = standard_resources[j];
 585                         if (std_res->start < res->start ||
 586                             std_res->start > res->end)
 587                                 continue;
 588                         if (std_res->end > res->end) {
 589                                 sub_res = memblock_alloc(sizeof(*sub_res), 8);
 590                                 if (!sub_res)
 591                                         panic("%s: Failed to allocate %zu bytes align=0x%x\n",
 592                                               __func__, sizeof(*sub_res), 8);
 593                                 *sub_res = *std_res;
 594                                 sub_res->end = res->end;
 595                                 std_res->start = res->end + 1;
 596                                 request_resource(res, sub_res);
 597                         } else {
 598                                 request_resource(res, std_res);
 599                         }
 600                 }
 601         }
 602 #ifdef CONFIG_CRASH_DUMP
 603         /*
 604          * Re-add removed crash kernel memory as reserved memory. This makes
 605          * sure it will be mapped with the identity mapping and struct pages
 606          * will be created, so it can be resized later on.
 607          * However add it later since the crash kernel resource should not be
 608          * part of the System RAM resource.
 609          */
 610         if (crashk_res.end) {
 611                 memblock_add_node(crashk_res.start, resource_size(&crashk_res),
 612                                   0, MEMBLOCK_NONE);
 613                 memblock_reserve(crashk_res.start, resource_size(&crashk_res));
 614                 insert_resource(&iomem_resource, &crashk_res);
 615         }
 616 #endif
 617 }
 618
 619 static void __init setup_memory_end(void)
 620 {
 621         memblock_remove(ident_map_size, PHYS_ADDR_MAX - ident_map_size);
 622         max_pfn = max_low_pfn = PFN_DOWN(ident_map_size);
 623         pr_notice("The maximum memory size is %luMB\n", ident_map_size >> 20);
 624 }
 625
 626 #ifdef CONFIG_CRASH_DUMP
 627
 628 /*
 629  * When kdump is enabled, we have to ensure that no memory from the area
 630  * [0 - crashkernel memory size] is set offline - it will be exchanged with
 631  * the crashkernel memory region when kdump is triggered. The crashkernel
 632  * memory region can never get offlined (pages are unmovable).
 633  */
 634 static int kdump_mem_notifier(struct notifier_block *nb,
 635                               unsigned long action, void *data)
 636 {
 637         struct memory_notify *arg = data;
 638
 639         if (action != MEM_GOING_OFFLINE)
 640                 return NOTIFY_OK;
 641         if (arg->start_pfn < PFN_DOWN(resource_size(&crashk_res)))
 642                 return NOTIFY_BAD;
 643         return NOTIFY_OK;
 644 }
 645
 646 static struct notifier_block kdump_mem_nb = {
 647         .notifier_call = kdump_mem_notifier,
 648 };
 649
 650 #endif
 651
 652 /*
 653  * Reserve memory for kdump kernel to be loaded with kexec
 654  */
 655 static void __init reserve_crashkernel(void)
 656 {
 657 #ifdef CONFIG_CRASH_DUMP
 658         unsigned long long crash_base, crash_size;
 659         phys_addr_t low, high;
 660         int rc;
 661
 662         rc = parse_crashkernel(boot_command_line, ident_map_size, &crash_size,
 663                                &crash_base);
 664
 665         crash_base = ALIGN(crash_base, KEXEC_CRASH_MEM_ALIGN);
 666         crash_size = ALIGN(crash_size, KEXEC_CRASH_MEM_ALIGN);
 667         if (rc || crash_size == 0)
 668                 return;
 669
 670         if (memblock.memory.regions[0].size < crash_size) {
 671                 pr_info("crashkernel reservation failed: %s\n",
 672                         "first memory chunk must be at least crashkernel size");
 673                 return;
 674         }
 675
 676         low = crash_base ?: oldmem_data.start;
 677         high = low + crash_size;
 678         if (low >= oldmem_data.start && high <= oldmem_data.start + oldmem_data.size) {
 679                 /* The crashkernel fits into OLDMEM, reuse OLDMEM */
 680                 crash_base = low;
 681         } else {
 682                 /* Find suitable area in free memory */
 683                 low = max_t(unsigned long, crash_size, sclp.hsa_size);
 684                 high = crash_base ? crash_base + crash_size : ULONG_MAX;
 685
 686                 if (crash_base && crash_base < low) {
 687                         pr_info("crashkernel reservation failed: %s\n",
 688                                 "crash_base too low");
 689                         return;
 690                 }
 691                 low = crash_base ?: low;
 692                 crash_base = memblock_phys_alloc_range(crash_size,
 693                                                        KEXEC_CRASH_MEM_ALIGN,
 694                                                        low, high);
 695         }
 696
 697         if (!crash_base) {
 698                 pr_info("crashkernel reservation failed: %s\n",
 699                         "no suitable area found");
 700                 return;
 701         }
 702
 703         if (register_memory_notifier(&kdump_mem_nb)) {
 704                 memblock_phys_free(crash_base, crash_size);
 705                 return;
 706         }
 707
 708         if (!oldmem_data.start && MACHINE_IS_VM)
 709                 diag10_range(PFN_DOWN(crash_base), PFN_DOWN(crash_size));
 710         crashk_res.start = crash_base;
 711         crashk_res.end = crash_base + crash_size - 1;
 712         memblock_remove(crash_base, crash_size);
 713         pr_info("Reserving %lluMB of memory at %lluMB "
 714                 "for crashkernel (System RAM: %luMB)\n",
 715                 crash_size >> 20, crash_base >> 20,
 716                 (unsigned long)memblock.memory.total_size >> 20);
 717         os_info_crashkernel_add(crash_base, crash_size);
 718 #endif
 719 }
 720
 721 /*
 722  * Reserve the initrd from being used by memblock
 723  */
 724 static void __init reserve_initrd(void)
 725 {
 726 #ifdef CONFIG_BLK_DEV_INITRD
 727         if (!initrd_data.start || !initrd_data.size)
 728                 return;
 729         initrd_start = (unsigned long)__va(initrd_data.start);
 730         initrd_end = initrd_start + initrd_data.size;
 731         memblock_reserve(initrd_data.start, initrd_data.size);
 732 #endif
 733 }
 734
 735 /*
 736  * Reserve the memory area used to pass the certificate lists
 737  */
 738 static void __init reserve_certificate_list(void)
 739 {
 740         if (ipl_cert_list_addr)
 741                 memblock_reserve(ipl_cert_list_addr, ipl_cert_list_size);
 742 }
 743
 744 static void __init reserve_mem_detect_info(void)
 745 {
 746         unsigned long start, size;
 747
 748         get_mem_detect_reserved(&start, &size);
 749         if (size)
 750                 memblock_reserve(start, size);
 751 }
 752
 753 static void __init free_mem_detect_info(void)
 754 {
 755         unsigned long start, size;
 756
 757         get_mem_detect_reserved(&start, &size);
 758         if (size)
 759                 memblock_phys_free(start, size);
 760 }
 761
 762 static const char * __init get_mem_info_source(void)
 763 {
 764         switch (mem_detect.info_source) {
 765         case MEM_DETECT_SCLP_STOR_INFO:
 766                 return "sclp storage info";
 767         case MEM_DETECT_DIAG260:
 768                 return "diag260";
 769         case MEM_DETECT_SCLP_READ_INFO:
 770                 return "sclp read info";
 771         case MEM_DETECT_BIN_SEARCH:
 772                 return "binary search";
 773         }
 774         return "none";
 775 }
 776
 777 static void __init memblock_add_mem_detect_info(void)
 778 {
 779         unsigned long start, end;
 780         int i;
 781
 782         pr_debug("physmem info source: %s (%hhd)\n",
 783                  get_mem_info_source(), mem_detect.info_source);
 784         /* keep memblock lists close to the kernel */
 785         memblock_set_bottom_up(true);
 786         for_each_mem_detect_block(i, &start, &end) {
 787                 memblock_add(start, end - start);
 788                 memblock_physmem_add(start, end - start);
 789         }
 790         memblock_set_bottom_up(false);
 791         memblock_set_node(0, ULONG_MAX, &memblock.memory, 0);
 792 }
 793
 794 /*
 795  * Check for initrd being in usable memory
 796  */
 797 static void __init check_initrd(void)
 798 {
 799 #ifdef CONFIG_BLK_DEV_INITRD
 800         if (initrd_data.start && initrd_data.size &&
 801             !memblock_is_region_memory(initrd_data.start, initrd_data.size)) {
 802                 pr_err("The initial RAM disk does not fit into the memory\n");
 803                 memblock_phys_free(initrd_data.start, initrd_data.size);
 804                 initrd_start = initrd_end = 0;
 805         }
 806 #endif
 807 }
 808
 809 /*
 810  * Reserve memory used for lowcore/command line/kernel image.
 811  */
 812 static void __init reserve_kernel(void)
 813 {
 814         memblock_reserve(0, STARTUP_NORMAL_OFFSET);
 815         memblock_reserve(OLDMEM_BASE, sizeof(unsigned long));
 816         memblock_reserve(OLDMEM_SIZE, sizeof(unsigned long));
 817         memblock_reserve(__amode31_base, __eamode31 - __samode31);
 818         memblock_reserve(__pa(sclp_early_sccb), EXT_SCCB_READ_SCP);
 819         memblock_reserve(__pa(_stext), _end - _stext);
 820 }
 821
 822 static void __init setup_memory(void)
 823 {
 824         phys_addr_t start, end;
 825         u64 i;
 826
 827         /*
 828          * Init storage key for present memory
 829          */
 830         for_each_mem_range(i, &start, &end)
 831                 storage_key_init_range(start, end);
 832
 833         psw_set_key(PAGE_DEFAULT_KEY);
 834 }
 835
 836 static void __init relocate_amode31_section(void)
 837 {
 838         unsigned long amode31_size = __eamode31 - __samode31;
 839         long amode31_offset = __amode31_base - __samode31;
 840         long *ptr;
 841
 842         pr_info("Relocating AMODE31 section of size 0x%08lx\n", amode31_size);
 843
 844         /* Move original AMODE31 section to the new one */
 845         memmove((void *)__amode31_base, (void *)__samode31, amode31_size);
 846         /* Zero out the old AMODE31 section to catch invalid accesses within it */
 847         memset((void *)__samode31, 0, amode31_size);
 848
 849         /* Update all AMODE31 region references */
 850         for (ptr = _start_amode31_refs; ptr != _end_amode31_refs; ptr++)
 851                 *ptr += amode31_offset;
 852 }
 853
 854 /* This must be called after AMODE31 relocation */
 855 static void __init setup_cr(void)
 856 {
 857         union ctlreg2 cr2;
 858         union ctlreg5 cr5;
 859         union ctlreg15 cr15;
 860
 861         __ctl_duct[1] = (unsigned long)__ctl_aste;
 862         __ctl_duct[2] = (unsigned long)__ctl_aste;
 863         __ctl_duct[4] = (unsigned long)__ctl_duald;
 864
 865         /* Update control registers CR2, CR5 and CR15 */
 866         __ctl_store(cr2.val, 2, 2);
 867         __ctl_store(cr5.val, 5, 5);
 868         __ctl_store(cr15.val, 15, 15);
 869         cr2.ducto = (unsigned long)__ctl_duct >> 6;
 870         cr5.pasteo = (unsigned long)__ctl_duct >> 6;
 871         cr15.lsea = (unsigned long)__ctl_linkage_stack >> 3;
 872         __ctl_load(cr2.val, 2, 2);
 873         __ctl_load(cr5.val, 5, 5);
 874         __ctl_load(cr15.val, 15, 15);
 875 }
 876
 877 /*
 878  * Add system information as device randomness
 879  */
 880 static void __init setup_randomness(void)
 881 {
 882         struct sysinfo_3_2_2 *vmms;
 883
 884         vmms = memblock_alloc(PAGE_SIZE, PAGE_SIZE);
 885         if (!vmms)
 886                 panic("Failed to allocate memory for sysinfo structure\n");
 887         if (stsi(vmms, 3, 2, 2) == 0 && vmms->count)
 888                 add_device_randomness(&vmms->vm, sizeof(vmms->vm[0]) * vmms->count);
 889         memblock_free(vmms, PAGE_SIZE);
 890
 891         if (cpacf_query_func(CPACF_PRNO, CPACF_PRNO_TRNG))
 892                 static_branch_enable(&s390_arch_random_available);
 893 }
 894
 895 /*
 896  * Find the correct size for the task_struct. This depends on
 897  * the size of the struct fpu at the end of the thread_struct
 898  * which is embedded in the task_struct.
 899  */
 900 static void __init setup_task_size(void)
 901 {
 902         int task_size = sizeof(struct task_struct);
 903
 904         if (!MACHINE_HAS_VX) {
 905                 task_size -= sizeof(__vector128) * __NUM_VXRS;
 906                 task_size += sizeof(freg_t) * __NUM_FPRS;
 907         }
 908         arch_task_struct_size = task_size;
 909 }
 910
 911 /*
 912  * Issue diagnose 318 to set the control program name and
 913  * version codes.
 914  */
 915 static void __init setup_control_program_code(void)
 916 {
 917         union diag318_info diag318_info = {
 918                 .cpnc = CPNC_LINUX,
 919                 .cpvc = 0,
 920         };
 921
 922         if (!sclp.has_diag318)
 923                 return;
 924
 925         diag_stat_inc(DIAG_STAT_X318);
 926         asm volatile("diag %0,0,0x318\n" : : "d" (diag318_info.val));
 927 }
 928
 929 /*
 930  * Print the component list from the IPL report
 931  */
 932 static void __init log_component_list(void)
 933 {
 934         struct ipl_rb_component_entry *ptr, *end;
 935         char *str;
 936
 937         if (!early_ipl_comp_list_addr)
 938                 return;
 939         if (ipl_block.hdr.flags & IPL_PL_FLAG_SIPL)
 940                 pr_info("Linux is running with Secure-IPL enabled\n");
 941         else
 942                 pr_info("Linux is running with Secure-IPL disabled\n");
 943         ptr = (void *) early_ipl_comp_list_addr;
 944         end = (void *) ptr + early_ipl_comp_list_size;
 945         pr_info("The IPL report contains the following components:\n");
 946         while (ptr < end) {
 947                 if (ptr->flags & IPL_RB_COMPONENT_FLAG_SIGNED) {
 948                         if (ptr->flags & IPL_RB_COMPONENT_FLAG_VERIFIED)
 949                                 str = "signed, verified";
 950                         else
 951                                 str = "signed, verification failed";
 952                 } else {
 953                         str = "not signed";
 954                 }
 955                 pr_info("%016llx - %016llx (%s)\n",
 956                         ptr->addr, ptr->addr + ptr->len, str);
 957                 ptr++;
 958         }
 959 }
 960
 961 /*
 962  * Setup function called from init/main.c just after the banner
 963  * was printed.
 964  */
 965
 966 void __init setup_arch(char **cmdline_p)
 967 {
 968         /*
 969          * print what head.S has found out about the machine
 970          */
 971         if (MACHINE_IS_VM)
 972                 pr_info("Linux is running as a z/VM "
 973                         "guest operating system in 64-bit mode\n");
 974         else if (MACHINE_IS_KVM)
 975                 pr_info("Linux is running under KVM in 64-bit mode\n");
 976         else if (MACHINE_IS_LPAR)
 977                 pr_info("Linux is running natively in 64-bit mode\n");
 978         else
 979                 pr_info("Linux is running as a guest in 64-bit mode\n");
 980
 981         log_component_list();
 982
 983         /* Have one command line that is parsed and saved in /proc/cmdline */
 984         /* boot_command_line has been already set up in early.c */
 985         *cmdline_p = boot_command_line;
 986
 987         ROOT_DEV = Root_RAM0;
 988
 989         setup_initial_init_mm(_text, _etext, _edata, _end);
 990
 991         if (IS_ENABLED(CONFIG_EXPOLINE_AUTO))
 992                 nospec_auto_detect();
 993
 994         jump_label_init();
 995         parse_early_param();
 996 #ifdef CONFIG_CRASH_DUMP
 997         /* Deactivate elfcorehdr= kernel parameter */
 998         elfcorehdr_addr = ELFCORE_ADDR_MAX;
 999 #endif
1000
1001         os_info_init();
1002         setup_ipl();
1003         setup_task_size();
1004         setup_control_program_code();
1005
1006         /* Do some memory reservations *before* memory is added to memblock */
1007         reserve_kernel();
1008         reserve_initrd();
1009         reserve_certificate_list();
1010         reserve_mem_detect_info();
1011         memblock_set_current_limit(ident_map_size);
1012         memblock_allow_resize();
1013
1014         /* Get information about *all* installed memory */
1015         memblock_add_mem_detect_info();
1016
1017         free_mem_detect_info();
1018         setup_memory_end();
1019         memblock_dump_all();
1020         setup_memory();
1021
1022         relocate_amode31_section();
1023         setup_cr();
1024         setup_uv();
1025         dma_contiguous_reserve(ident_map_size);
1026         vmcp_cma_reserve();
1027         if (MACHINE_HAS_EDAT2)
1028                 hugetlb_cma_reserve(PUD_SHIFT - PAGE_SHIFT);
1029
1030         check_initrd();
1031         reserve_crashkernel();
1032 #ifdef CONFIG_CRASH_DUMP
1033         /*
1034          * Be aware that smp_save_dump_secondary_cpus() triggers a system reset.
1035          * Therefore CPU and device initialization should be done afterwards.
1036          */
1037         smp_save_dump_secondary_cpus();
1038 #endif
1039
1040         setup_resources();
1041         setup_lowcore_dat_off();
1042         smp_fill_possible_mask();
1043         cpu_detect_mhz_feature();
1044         cpu_init();
1045         numa_setup();
1046         smp_detect_cpus();
1047         topology_init_early();
1048
1049         if (test_facility(193))
1050                 static_branch_enable(&cpu_has_bear);
1051
1052         /*
1053          * Create kernel page tables and switch to virtual addressing.
1054          */
1055         paging_init();
1056         memcpy_real_init();
1057         /*
1058          * After paging_init created the kernel page table, the new PSWs
1059          * in lowcore can now run with DAT enabled.
1060          */
1061         setup_lowcore_dat_on();
1062 #ifdef CONFIG_CRASH_DUMP
1063         smp_save_dump_ipl_cpu();
1064 #endif
1065
1066         /* Setup default console */
1067         conmode_default();
1068         set_preferred_console();
1069
1070         apply_alternative_instructions();
1071         if (IS_ENABLED(CONFIG_EXPOLINE))
1072                 nospec_init_branches();
1073
1074         /* Setup zfcp/nvme dump support */
1075         setup_zfcpdump();
1076
1077         /* Add system specific data to the random pool */
1078         setup_randomness();
1079 }