1/* SPDX-License-Identifier: GPL-2.0 */ 2/* 3 * S390 low-level entry points. 4 * 5 * Copyright IBM Corp. 1999, 2012 6 * Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com), 7 * Hartmut Penner (hp@de.ibm.com), 8 * Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com), 9 * Heiko Carstens <heiko.carstens@de.ibm.com> 10 */ 11 12#include <linux/init.h> 13#include <linux/linkage.h> 14#include <asm/processor.h> 15#include <asm/cache.h> 16#include <asm/ctl_reg.h> 17#include <asm/errno.h> 18#include <asm/ptrace.h> 19#include <asm/thread_info.h> 20#include <asm/asm-offsets.h> 21#include <asm/unistd.h> 22#include <asm/page.h> 23#include <asm/sigp.h> 24#include <asm/irq.h> 25#include <asm/vx-insn.h> 26#include <asm/setup.h> 27#include <asm/nmi.h> 28#include <asm/export.h> 29 30__PT_R0 = __PT_GPRS 31__PT_R1 = __PT_GPRS + 8 32__PT_R2 = __PT_GPRS + 16 33__PT_R3 = __PT_GPRS + 24 34__PT_R4 = __PT_GPRS + 32 35__PT_R5 = __PT_GPRS + 40 36__PT_R6 = __PT_GPRS + 48 37__PT_R7 = __PT_GPRS + 56 38__PT_R8 = __PT_GPRS + 64 39__PT_R9 = __PT_GPRS + 72 40__PT_R10 = __PT_GPRS + 80 41__PT_R11 = __PT_GPRS + 88 42__PT_R12 = __PT_GPRS + 96 43__PT_R13 = __PT_GPRS + 104 44__PT_R14 = __PT_GPRS + 112 45__PT_R15 = __PT_GPRS + 120 46 47STACK_SHIFT = PAGE_SHIFT + THREAD_SIZE_ORDER 48STACK_SIZE = 1 << STACK_SHIFT 49STACK_INIT = STACK_SIZE - STACK_FRAME_OVERHEAD - __PT_SIZE 50 51_TIF_WORK = (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_NEED_RESCHED | \ 52 _TIF_UPROBE | _TIF_GUARDED_STORAGE | _TIF_PATCH_PENDING) 53_TIF_TRACE = (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | _TIF_SECCOMP | \ 54 _TIF_SYSCALL_TRACEPOINT) 55_CIF_WORK = (_CIF_MCCK_PENDING | _CIF_ASCE_PRIMARY | \ 56 _CIF_ASCE_SECONDARY | _CIF_FPU) 57_PIF_WORK = (_PIF_PER_TRAP | _PIF_SYSCALL_RESTART) 58 59#define BASED(name) name-cleanup_critical(%r13) 60 61 .macro TRACE_IRQS_ON 62#ifdef CONFIG_TRACE_IRQFLAGS 63 basr %r2,%r0 64 brasl %r14,trace_hardirqs_on_caller 65#endif 66 .endm 67 68 .macro TRACE_IRQS_OFF 69#ifdef CONFIG_TRACE_IRQFLAGS 70 basr %r2,%r0 71 brasl %r14,trace_hardirqs_off_caller 72#endif 73 .endm 74 75 .macro LOCKDEP_SYS_EXIT 76#ifdef CONFIG_LOCKDEP 77 tm __PT_PSW+1(%r11),0x01 # returning to user ? 78 jz .+10 79 brasl %r14,lockdep_sys_exit 80#endif 81 .endm 82 83 .macro CHECK_STACK stacksize,savearea 84#ifdef CONFIG_CHECK_STACK 85 tml %r15,\stacksize - CONFIG_STACK_GUARD 86 lghi %r14,\savearea 87 jz stack_overflow 88#endif 89 .endm 90 91 .macro SWITCH_ASYNC savearea,timer 92 tmhh %r8,0x0001 # interrupting from user ? 93 jnz 1f 94 lgr %r14,%r9 95 slg %r14,BASED(.Lcritical_start) 96 clg %r14,BASED(.Lcritical_length) 97 jhe 0f 98 lghi %r11,\savearea # inside critical section, do cleanup 99 brasl %r14,cleanup_critical 100 tmhh %r8,0x0001 # retest problem state after cleanup 101 jnz 1f 1020: lg %r14,__LC_ASYNC_STACK # are we already on the async stack? 103 slgr %r14,%r15 104 srag %r14,%r14,STACK_SHIFT 105 jnz 2f 106 CHECK_STACK 1<<STACK_SHIFT,\savearea 107 aghi %r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE) 108 j 3f 1091: UPDATE_VTIME %r14,%r15,\timer 110 BPENTER __TI_flags(%r12),_TIF_ISOLATE_BP 1112: lg %r15,__LC_ASYNC_STACK # load async stack 1123: la %r11,STACK_FRAME_OVERHEAD(%r15) 113 .endm 114 115 .macro UPDATE_VTIME w1,w2,enter_timer 116 lg \w1,__LC_EXIT_TIMER 117 lg \w2,__LC_LAST_UPDATE_TIMER 118 slg \w1,\enter_timer 119 slg \w2,__LC_EXIT_TIMER 120 alg \w1,__LC_USER_TIMER 121 alg \w2,__LC_SYSTEM_TIMER 122 stg \w1,__LC_USER_TIMER 123 stg \w2,__LC_SYSTEM_TIMER 124 mvc __LC_LAST_UPDATE_TIMER(8),\enter_timer 125 .endm 126 127 .macro REENABLE_IRQS 128 stg %r8,__LC_RETURN_PSW 129 ni __LC_RETURN_PSW,0xbf 130 ssm __LC_RETURN_PSW 131 .endm 132 133 .macro STCK savearea 134#ifdef CONFIG_HAVE_MARCH_Z9_109_FEATURES 135 .insn s,0xb27c0000,\savearea # store clock fast 136#else 137 .insn s,0xb2050000,\savearea # store clock 138#endif 139 .endm 140 141 /* 142 * The TSTMSK macro generates a test-under-mask instruction by 143 * calculating the memory offset for the specified mask value. 144 * Mask value can be any constant. The macro shifts the mask 145 * value to calculate the memory offset for the test-under-mask 146 * instruction. 147 */ 148 .macro TSTMSK addr, mask, size=8, bytepos=0 149 .if (\bytepos < \size) && (\mask >> 8) 150 .if (\mask & 0xff) 151 .error "Mask exceeds byte boundary" 152 .endif 153 TSTMSK \addr, "(\mask >> 8)", \size, "(\bytepos + 1)" 154 .exitm 155 .endif 156 .ifeq \mask 157 .error "Mask must not be zero" 158 .endif 159 off = \size - \bytepos - 1 160 tm off+\addr, \mask 161 .endm 162 163 .macro BPOFF 164 .pushsection .altinstr_replacement, "ax" 165660: .long 0xb2e8c000 166 .popsection 167661: .long 0x47000000 168 .pushsection .altinstructions, "a" 169 .long 661b - . 170 .long 660b - . 171 .word 82 172 .byte 4 173 .byte 4 174 .popsection 175 .endm 176 177 .macro BPON 178 .pushsection .altinstr_replacement, "ax" 179662: .long 0xb2e8d000 180 .popsection 181663: .long 0x47000000 182 .pushsection .altinstructions, "a" 183 .long 663b - . 184 .long 662b - . 185 .word 82 186 .byte 4 187 .byte 4 188 .popsection 189 .endm 190 191 .macro BPENTER tif_ptr,tif_mask 192 .pushsection .altinstr_replacement, "ax" 193662: .word 0xc004, 0x0000, 0x0000 # 6 byte nop 194 .word 0xc004, 0x0000, 0x0000 # 6 byte nop 195 .popsection 196664: TSTMSK \tif_ptr,\tif_mask 197 jz . + 8 198 .long 0xb2e8d000 199 .pushsection .altinstructions, "a" 200 .long 664b - . 201 .long 662b - . 202 .word 82 203 .byte 12 204 .byte 12 205 .popsection 206 .endm 207 208 .macro BPEXIT tif_ptr,tif_mask 209 TSTMSK \tif_ptr,\tif_mask 210 .pushsection .altinstr_replacement, "ax" 211662: jnz . + 8 212 .long 0xb2e8d000 213 .popsection 214664: jz . + 8 215 .long 0xb2e8c000 216 .pushsection .altinstructions, "a" 217 .long 664b - . 218 .long 662b - . 219 .word 82 220 .byte 8 221 .byte 8 222 .popsection 223 .endm 224 225#ifdef CONFIG_EXPOLINE 226 227 .macro GEN_BR_THUNK name,reg,tmp 228 .section .text.\name,"axG",@progbits,\name,comdat 229 .globl \name 230 .hidden \name 231 .type \name,@function 232\name: 233 .cfi_startproc 234#ifdef CONFIG_HAVE_MARCH_Z10_FEATURES 235 exrl 0,0f 236#else 237 larl \tmp,0f 238 ex 0,0(\tmp) 239#endif 240 j . 2410: br \reg 242 .cfi_endproc 243 .endm 244 245 GEN_BR_THUNK __s390x_indirect_jump_r1use_r9,%r9,%r1 246 GEN_BR_THUNK __s390x_indirect_jump_r1use_r14,%r14,%r1 247 GEN_BR_THUNK __s390x_indirect_jump_r11use_r14,%r14,%r11 248 249 .macro BASR_R14_R9 2500: brasl %r14,__s390x_indirect_jump_r1use_r9 251 .pushsection .s390_indirect_branches,"a",@progbits 252 .long 0b-. 253 .popsection 254 .endm 255 256 .macro BR_R1USE_R14 2570: jg __s390x_indirect_jump_r1use_r14 258 .pushsection .s390_indirect_branches,"a",@progbits 259 .long 0b-. 260 .popsection 261 .endm 262 263 .macro BR_R11USE_R14 2640: jg __s390x_indirect_jump_r11use_r14 265 .pushsection .s390_indirect_branches,"a",@progbits 266 .long 0b-. 267 .popsection 268 .endm 269 270#else /* CONFIG_EXPOLINE */ 271 272 .macro BASR_R14_R9 273 basr %r14,%r9 274 .endm 275 276 .macro BR_R1USE_R14 277 br %r14 278 .endm 279 280 .macro BR_R11USE_R14 281 br %r14 282 .endm 283 284#endif /* CONFIG_EXPOLINE */ 285 286 287 .section .kprobes.text, "ax" 288.Ldummy: 289 /* 290 * This nop exists only in order to avoid that __switch_to starts at 291 * the beginning of the kprobes text section. In that case we would 292 * have several symbols at the same address. E.g. objdump would take 293 * an arbitrary symbol name when disassembling this code. 294 * With the added nop in between the __switch_to symbol is unique 295 * again. 296 */ 297 nop 0 298 299ENTRY(__bpon) 300 .globl __bpon 301 BPON 302 BR_R1USE_R14 303 304/* 305 * Scheduler resume function, called by switch_to 306 * gpr2 = (task_struct *) prev 307 * gpr3 = (task_struct *) next 308 * Returns: 309 * gpr2 = prev 310 */ 311ENTRY(__switch_to) 312 stmg %r6,%r15,__SF_GPRS(%r15) # store gprs of prev task 313 lghi %r4,__TASK_stack 314 lghi %r1,__TASK_thread 315 lg %r5,0(%r4,%r3) # start of kernel stack of next 316 stg %r15,__THREAD_ksp(%r1,%r2) # store kernel stack of prev 317 lgr %r15,%r5 318 aghi %r15,STACK_INIT # end of kernel stack of next 319 stg %r3,__LC_CURRENT # store task struct of next 320 stg %r15,__LC_KERNEL_STACK # store end of kernel stack 321 lg %r15,__THREAD_ksp(%r1,%r3) # load kernel stack of next 322 aghi %r3,__TASK_pid 323 mvc __LC_CURRENT_PID(4,%r0),0(%r3) # store pid of next 324 lmg %r6,%r15,__SF_GPRS(%r15) # load gprs of next task 325 TSTMSK __LC_MACHINE_FLAGS,MACHINE_FLAG_LPP 326 jz 0f 327 .insn s,0xb2800000,__LC_LPP # set program parameter 3280: BR_R1USE_R14 329 330.L__critical_start: 331 332#if IS_ENABLED(CONFIG_KVM) 333/* 334 * sie64a calling convention: 335 * %r2 pointer to sie control block 336 * %r3 guest register save area 337 */ 338ENTRY(sie64a) 339 stmg %r6,%r14,__SF_GPRS(%r15) # save kernel registers 340 lg %r12,__LC_CURRENT 341 stg %r2,__SF_EMPTY(%r15) # save control block pointer 342 stg %r3,__SF_EMPTY+8(%r15) # save guest register save area 343 xc __SF_EMPTY+16(8,%r15),__SF_EMPTY+16(%r15) # reason code = 0 344 mvc __SF_EMPTY+24(8,%r15),__TI_flags(%r12) # copy thread flags 345 TSTMSK __LC_CPU_FLAGS,_CIF_FPU # load guest fp/vx registers ? 346 jno .Lsie_load_guest_gprs 347 brasl %r14,load_fpu_regs # load guest fp/vx regs 348.Lsie_load_guest_gprs: 349 lmg %r0,%r13,0(%r3) # load guest gprs 0-13 350 lg %r14,__LC_GMAP # get gmap pointer 351 ltgr %r14,%r14 352 jz .Lsie_gmap 353 lctlg %c1,%c1,__GMAP_ASCE(%r14) # load primary asce 354.Lsie_gmap: 355 lg %r14,__SF_EMPTY(%r15) # get control block pointer 356 oi __SIE_PROG0C+3(%r14),1 # we are going into SIE now 357 tm __SIE_PROG20+3(%r14),3 # last exit... 358 jnz .Lsie_skip 359 TSTMSK __LC_CPU_FLAGS,_CIF_FPU 360 jo .Lsie_skip # exit if fp/vx regs changed 361 BPEXIT __SF_EMPTY+24(%r15),(_TIF_ISOLATE_BP|_TIF_ISOLATE_BP_GUEST) 362.Lsie_entry: 363 sie 0(%r14) 364.Lsie_exit: 365 BPOFF 366 BPENTER __SF_EMPTY+24(%r15),(_TIF_ISOLATE_BP|_TIF_ISOLATE_BP_GUEST) 367.Lsie_skip: 368 ni __SIE_PROG0C+3(%r14),0xfe # no longer in SIE 369 lctlg %c1,%c1,__LC_USER_ASCE # load primary asce 370.Lsie_done: 371# some program checks are suppressing. C code (e.g. do_protection_exception) 372# will rewind the PSW by the ILC, which is often 4 bytes in case of SIE. There 373# are some corner cases (e.g. runtime instrumentation) where ILC is unpredictable. 374# Other instructions between sie64a and .Lsie_done should not cause program 375# interrupts. So lets use 3 nops as a landing pad for all possible rewinds. 376# See also .Lcleanup_sie 377.Lrewind_pad6: 378 nopr 7 379.Lrewind_pad4: 380 nopr 7 381.Lrewind_pad2: 382 nopr 7 383 .globl sie_exit 384sie_exit: 385 lg %r14,__SF_EMPTY+8(%r15) # load guest register save area 386 stmg %r0,%r13,0(%r14) # save guest gprs 0-13 387 xgr %r0,%r0 # clear guest registers to 388 xgr %r1,%r1 # prevent speculative use 389 xgr %r2,%r2 390 xgr %r3,%r3 391 xgr %r4,%r4 392 xgr %r5,%r5 393 lmg %r6,%r14,__SF_GPRS(%r15) # restore kernel registers 394 lg %r2,__SF_EMPTY+16(%r15) # return exit reason code 395 BR_R1USE_R14 396.Lsie_fault: 397 lghi %r14,-EFAULT 398 stg %r14,__SF_EMPTY+16(%r15) # set exit reason code 399 j sie_exit 400 401 EX_TABLE(.Lrewind_pad6,.Lsie_fault) 402 EX_TABLE(.Lrewind_pad4,.Lsie_fault) 403 EX_TABLE(.Lrewind_pad2,.Lsie_fault) 404 EX_TABLE(sie_exit,.Lsie_fault) 405EXPORT_SYMBOL(sie64a) 406EXPORT_SYMBOL(sie_exit) 407#endif 408 409/* 410 * SVC interrupt handler routine. System calls are synchronous events and 411 * are executed with interrupts enabled. 412 */ 413 414ENTRY(system_call) 415 stpt __LC_SYNC_ENTER_TIMER 416.Lsysc_stmg: 417 stmg %r8,%r15,__LC_SAVE_AREA_SYNC 418 BPOFF 419 lg %r12,__LC_CURRENT 420 lghi %r13,__TASK_thread 421 lghi %r14,_PIF_SYSCALL 422.Lsysc_per: 423 lg %r15,__LC_KERNEL_STACK 424 la %r11,STACK_FRAME_OVERHEAD(%r15) # pointer to pt_regs 425.Lsysc_vtime: 426 UPDATE_VTIME %r8,%r9,__LC_SYNC_ENTER_TIMER 427 BPENTER __TI_flags(%r12),_TIF_ISOLATE_BP 428 stmg %r0,%r7,__PT_R0(%r11) 429 # clear user controlled register to prevent speculative use 430 xgr %r0,%r0 431 mvc __PT_R8(64,%r11),__LC_SAVE_AREA_SYNC 432 mvc __PT_PSW(16,%r11),__LC_SVC_OLD_PSW 433 mvc __PT_INT_CODE(4,%r11),__LC_SVC_ILC 434 stg %r14,__PT_FLAGS(%r11) 435.Lsysc_do_svc: 436 # load address of system call table 437 lg %r10,__THREAD_sysc_table(%r13,%r12) 438 llgh %r8,__PT_INT_CODE+2(%r11) 439 slag %r8,%r8,2 # shift and test for svc 0 440 jnz .Lsysc_nr_ok 441 # svc 0: system call number in %r1 442 llgfr %r1,%r1 # clear high word in r1 443 cghi %r1,NR_syscalls 444 jnl .Lsysc_nr_ok 445 sth %r1,__PT_INT_CODE+2(%r11) 446 slag %r8,%r1,2 447.Lsysc_nr_ok: 448 xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15) 449 stg %r2,__PT_ORIG_GPR2(%r11) 450 stg %r7,STACK_FRAME_OVERHEAD(%r15) 451 lgf %r9,0(%r8,%r10) # get system call add. 452 TSTMSK __TI_flags(%r12),_TIF_TRACE 453 jnz .Lsysc_tracesys 454 BASR_R14_R9 # call sys_xxxx 455 stg %r2,__PT_R2(%r11) # store return value 456 457.Lsysc_return: 458 LOCKDEP_SYS_EXIT 459.Lsysc_tif: 460 TSTMSK __PT_FLAGS(%r11),_PIF_WORK 461 jnz .Lsysc_work 462 TSTMSK __TI_flags(%r12),_TIF_WORK 463 jnz .Lsysc_work # check for work 464 TSTMSK __LC_CPU_FLAGS,_CIF_WORK 465 jnz .Lsysc_work 466 BPEXIT __TI_flags(%r12),_TIF_ISOLATE_BP 467.Lsysc_restore: 468 lg %r14,__LC_VDSO_PER_CPU 469 lmg %r0,%r10,__PT_R0(%r11) 470 mvc __LC_RETURN_PSW(16),__PT_PSW(%r11) 471.Lsysc_exit_timer: 472 stpt __LC_EXIT_TIMER 473 mvc __VDSO_ECTG_BASE(16,%r14),__LC_EXIT_TIMER 474 lmg %r11,%r15,__PT_R11(%r11) 475 lpswe __LC_RETURN_PSW 476.Lsysc_done: 477 478# 479# One of the work bits is on. Find out which one. 480# 481.Lsysc_work: 482 TSTMSK __LC_CPU_FLAGS,_CIF_MCCK_PENDING 483 jo .Lsysc_mcck_pending 484 TSTMSK __TI_flags(%r12),_TIF_NEED_RESCHED 485 jo .Lsysc_reschedule 486 TSTMSK __PT_FLAGS(%r11),_PIF_SYSCALL_RESTART 487 jo .Lsysc_syscall_restart 488#ifdef CONFIG_UPROBES 489 TSTMSK __TI_flags(%r12),_TIF_UPROBE 490 jo .Lsysc_uprobe_notify 491#endif 492 TSTMSK __TI_flags(%r12),_TIF_GUARDED_STORAGE 493 jo .Lsysc_guarded_storage 494 TSTMSK __PT_FLAGS(%r11),_PIF_PER_TRAP 495 jo .Lsysc_singlestep 496#ifdef CONFIG_LIVEPATCH 497 TSTMSK __TI_flags(%r12),_TIF_PATCH_PENDING 498 jo .Lsysc_patch_pending # handle live patching just before 499 # signals and possible syscall restart 500#endif 501 TSTMSK __PT_FLAGS(%r11),_PIF_SYSCALL_RESTART 502 jo .Lsysc_syscall_restart 503 TSTMSK __TI_flags(%r12),_TIF_SIGPENDING 504 jo .Lsysc_sigpending 505 TSTMSK __TI_flags(%r12),_TIF_NOTIFY_RESUME 506 jo .Lsysc_notify_resume 507 TSTMSK __LC_CPU_FLAGS,_CIF_FPU 508 jo .Lsysc_vxrs 509 TSTMSK __LC_CPU_FLAGS,(_CIF_ASCE_PRIMARY|_CIF_ASCE_SECONDARY) 510 jnz .Lsysc_asce 511 j .Lsysc_return # beware of critical section cleanup 512 513# 514# _TIF_NEED_RESCHED is set, call schedule 515# 516.Lsysc_reschedule: 517 larl %r14,.Lsysc_return 518 jg schedule 519 520# 521# _CIF_MCCK_PENDING is set, call handler 522# 523.Lsysc_mcck_pending: 524 larl %r14,.Lsysc_return 525 jg s390_handle_mcck # TIF bit will be cleared by handler 526 527# 528# _CIF_ASCE_PRIMARY and/or _CIF_ASCE_SECONDARY set, load user space asce 529# 530.Lsysc_asce: 531 ni __LC_CPU_FLAGS+7,255-_CIF_ASCE_SECONDARY 532 lctlg %c7,%c7,__LC_VDSO_ASCE # load secondary asce 533 TSTMSK __LC_CPU_FLAGS,_CIF_ASCE_PRIMARY 534 jz .Lsysc_return 535#ifndef CONFIG_HAVE_MARCH_Z10_FEATURES 536 tm __LC_STFLE_FAC_LIST+3,0x10 # has MVCOS ? 537 jnz .Lsysc_set_fs_fixup 538 ni __LC_CPU_FLAGS+7,255-_CIF_ASCE_PRIMARY 539 lctlg %c1,%c1,__LC_USER_ASCE # load primary asce 540 j .Lsysc_return 541.Lsysc_set_fs_fixup: 542#endif 543 larl %r14,.Lsysc_return 544 jg set_fs_fixup 545 546# 547# CIF_FPU is set, restore floating-point controls and floating-point registers. 548# 549.Lsysc_vxrs: 550 larl %r14,.Lsysc_return 551 jg load_fpu_regs 552 553# 554# _TIF_SIGPENDING is set, call do_signal 555# 556.Lsysc_sigpending: 557 lgr %r2,%r11 # pass pointer to pt_regs 558 brasl %r14,do_signal 559 TSTMSK __PT_FLAGS(%r11),_PIF_SYSCALL 560 jno .Lsysc_return 561.Lsysc_do_syscall: 562 lghi %r13,__TASK_thread 563 lmg %r2,%r7,__PT_R2(%r11) # load svc arguments 564 lghi %r1,0 # svc 0 returns -ENOSYS 565 j .Lsysc_do_svc 566 567# 568# _TIF_NOTIFY_RESUME is set, call do_notify_resume 569# 570.Lsysc_notify_resume: 571 lgr %r2,%r11 # pass pointer to pt_regs 572 larl %r14,.Lsysc_return 573 jg do_notify_resume 574 575# 576# _TIF_UPROBE is set, call uprobe_notify_resume 577# 578#ifdef CONFIG_UPROBES 579.Lsysc_uprobe_notify: 580 lgr %r2,%r11 # pass pointer to pt_regs 581 larl %r14,.Lsysc_return 582 jg uprobe_notify_resume 583#endif 584 585# 586# _TIF_GUARDED_STORAGE is set, call guarded_storage_load 587# 588.Lsysc_guarded_storage: 589 lgr %r2,%r11 # pass pointer to pt_regs 590 larl %r14,.Lsysc_return 591 jg gs_load_bc_cb 592# 593# _TIF_PATCH_PENDING is set, call klp_update_patch_state 594# 595#ifdef CONFIG_LIVEPATCH 596.Lsysc_patch_pending: 597 lg %r2,__LC_CURRENT # pass pointer to task struct 598 larl %r14,.Lsysc_return 599 jg klp_update_patch_state 600#endif 601 602# 603# _PIF_PER_TRAP is set, call do_per_trap 604# 605.Lsysc_singlestep: 606 ni __PT_FLAGS+7(%r11),255-_PIF_PER_TRAP 607 lgr %r2,%r11 # pass pointer to pt_regs 608 larl %r14,.Lsysc_return 609 jg do_per_trap 610 611# 612# _PIF_SYSCALL_RESTART is set, repeat the current system call 613# 614.Lsysc_syscall_restart: 615 ni __PT_FLAGS+7(%r11),255-_PIF_SYSCALL_RESTART 616 lmg %r1,%r7,__PT_R1(%r11) # load svc arguments 617 lg %r2,__PT_ORIG_GPR2(%r11) 618 j .Lsysc_do_svc 619 620# 621# call tracehook_report_syscall_entry/tracehook_report_syscall_exit before 622# and after the system call 623# 624.Lsysc_tracesys: 625 lgr %r2,%r11 # pass pointer to pt_regs 626 la %r3,0 627 llgh %r0,__PT_INT_CODE+2(%r11) 628 stg %r0,__PT_R2(%r11) 629 brasl %r14,do_syscall_trace_enter 630 lghi %r0,NR_syscalls 631 clgr %r0,%r2 632 jnh .Lsysc_tracenogo 633 sllg %r8,%r2,2 634 lgf %r9,0(%r8,%r10) 635.Lsysc_tracego: 636 lmg %r3,%r7,__PT_R3(%r11) 637 stg %r7,STACK_FRAME_OVERHEAD(%r15) 638 lg %r2,__PT_ORIG_GPR2(%r11) 639 BASR_R14_R9 # call sys_xxx 640 stg %r2,__PT_R2(%r11) # store return value 641.Lsysc_tracenogo: 642 TSTMSK __TI_flags(%r12),_TIF_TRACE 643 jz .Lsysc_return 644 lgr %r2,%r11 # pass pointer to pt_regs 645 larl %r14,.Lsysc_return 646 jg do_syscall_trace_exit 647 648# 649# a new process exits the kernel with ret_from_fork 650# 651ENTRY(ret_from_fork) 652 la %r11,STACK_FRAME_OVERHEAD(%r15) 653 lg %r12,__LC_CURRENT 654 brasl %r14,schedule_tail 655 TRACE_IRQS_ON 656 ssm __LC_SVC_NEW_PSW # reenable interrupts 657 tm __PT_PSW+1(%r11),0x01 # forking a kernel thread ? 658 jne .Lsysc_tracenogo 659 # it's a kernel thread 660 lmg %r9,%r10,__PT_R9(%r11) # load gprs 661ENTRY(kernel_thread_starter) 662 la %r2,0(%r10) 663 BASR_R14_R9 664 j .Lsysc_tracenogo 665 666/* 667 * Program check handler routine 668 */ 669 670ENTRY(pgm_check_handler) 671 stpt __LC_SYNC_ENTER_TIMER 672 BPOFF 673 stmg %r8,%r15,__LC_SAVE_AREA_SYNC 674 lg %r10,__LC_LAST_BREAK 675 lg %r12,__LC_CURRENT 676 lghi %r11,0 677 larl %r13,cleanup_critical 678 lmg %r8,%r9,__LC_PGM_OLD_PSW 679 tmhh %r8,0x0001 # test problem state bit 680 jnz 2f # -> fault in user space 681#if IS_ENABLED(CONFIG_KVM) 682 # cleanup critical section for program checks in sie64a 683 lgr %r14,%r9 684 slg %r14,BASED(.Lsie_critical_start) 685 clg %r14,BASED(.Lsie_critical_length) 686 jhe 0f 687 lg %r14,__SF_EMPTY(%r15) # get control block pointer 688 ni __SIE_PROG0C+3(%r14),0xfe # no longer in SIE 689 lctlg %c1,%c1,__LC_USER_ASCE # load primary asce 690 larl %r9,sie_exit # skip forward to sie_exit 691 lghi %r11,_PIF_GUEST_FAULT 692#endif 6930: tmhh %r8,0x4000 # PER bit set in old PSW ? 694 jnz 1f # -> enabled, can't be a double fault 695 tm __LC_PGM_ILC+3,0x80 # check for per exception 696 jnz .Lpgm_svcper # -> single stepped svc 6971: CHECK_STACK STACK_SIZE,__LC_SAVE_AREA_SYNC 698 aghi %r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE) 699 j 4f 7002: UPDATE_VTIME %r14,%r15,__LC_SYNC_ENTER_TIMER 701 BPENTER __TI_flags(%r12),_TIF_ISOLATE_BP 702 lg %r15,__LC_KERNEL_STACK 703 lgr %r14,%r12 704 aghi %r14,__TASK_thread # pointer to thread_struct 705 lghi %r13,__LC_PGM_TDB 706 tm __LC_PGM_ILC+2,0x02 # check for transaction abort 707 jz 3f 708 mvc __THREAD_trap_tdb(256,%r14),0(%r13) 7093: stg %r10,__THREAD_last_break(%r14) 7104: lgr %r13,%r11 711 la %r11,STACK_FRAME_OVERHEAD(%r15) 712 stmg %r0,%r7,__PT_R0(%r11) 713 # clear user controlled registers to prevent speculative use 714 xgr %r0,%r0 715 xgr %r1,%r1 716 xgr %r2,%r2 717 xgr %r3,%r3 718 xgr %r4,%r4 719 xgr %r5,%r5 720 xgr %r6,%r6 721 xgr %r7,%r7 722 mvc __PT_R8(64,%r11),__LC_SAVE_AREA_SYNC 723 stmg %r8,%r9,__PT_PSW(%r11) 724 mvc __PT_INT_CODE(4,%r11),__LC_PGM_ILC 725 mvc __PT_INT_PARM_LONG(8,%r11),__LC_TRANS_EXC_CODE 726 stg %r13,__PT_FLAGS(%r11) 727 stg %r10,__PT_ARGS(%r11) 728 tm __LC_PGM_ILC+3,0x80 # check for per exception 729 jz 5f 730 tmhh %r8,0x0001 # kernel per event ? 731 jz .Lpgm_kprobe 732 oi __PT_FLAGS+7(%r11),_PIF_PER_TRAP 733 mvc __THREAD_per_address(8,%r14),__LC_PER_ADDRESS 734 mvc __THREAD_per_cause(2,%r14),__LC_PER_CODE 735 mvc __THREAD_per_paid(1,%r14),__LC_PER_ACCESS_ID 7365: REENABLE_IRQS 737 xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15) 738 larl %r1,pgm_check_table 739 llgh %r10,__PT_INT_CODE+2(%r11) 740 nill %r10,0x007f 741 sll %r10,2 742 je .Lpgm_return 743 lgf %r9,0(%r10,%r1) # load address of handler routine 744 lgr %r2,%r11 # pass pointer to pt_regs 745 BASR_R14_R9 # branch to interrupt-handler 746.Lpgm_return: 747 LOCKDEP_SYS_EXIT 748 tm __PT_PSW+1(%r11),0x01 # returning to user ? 749 jno .Lsysc_restore 750 TSTMSK __PT_FLAGS(%r11),_PIF_SYSCALL 751 jo .Lsysc_do_syscall 752 j .Lsysc_tif 753 754# 755# PER event in supervisor state, must be kprobes 756# 757.Lpgm_kprobe: 758 REENABLE_IRQS 759 xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15) 760 lgr %r2,%r11 # pass pointer to pt_regs 761 brasl %r14,do_per_trap 762 j .Lpgm_return 763 764# 765# single stepped system call 766# 767.Lpgm_svcper: 768 mvc __LC_RETURN_PSW(8),__LC_SVC_NEW_PSW 769 lghi %r13,__TASK_thread 770 larl %r14,.Lsysc_per 771 stg %r14,__LC_RETURN_PSW+8 772 lghi %r14,_PIF_SYSCALL | _PIF_PER_TRAP 773 lpswe __LC_RETURN_PSW # branch to .Lsysc_per and enable irqs 774 775/* 776 * IO interrupt handler routine 777 */ 778ENTRY(io_int_handler) 779 STCK __LC_INT_CLOCK 780 stpt __LC_ASYNC_ENTER_TIMER 781 BPOFF 782 stmg %r8,%r15,__LC_SAVE_AREA_ASYNC 783 lg %r12,__LC_CURRENT 784 larl %r13,cleanup_critical 785 lmg %r8,%r9,__LC_IO_OLD_PSW 786 SWITCH_ASYNC __LC_SAVE_AREA_ASYNC,__LC_ASYNC_ENTER_TIMER 787 stmg %r0,%r7,__PT_R0(%r11) 788 # clear user controlled registers to prevent speculative use 789 xgr %r0,%r0 790 xgr %r1,%r1 791 xgr %r2,%r2 792 xgr %r3,%r3 793 xgr %r4,%r4 794 xgr %r5,%r5 795 xgr %r6,%r6 796 xgr %r7,%r7 797 xgr %r10,%r10 798 mvc __PT_R8(64,%r11),__LC_SAVE_AREA_ASYNC 799 stmg %r8,%r9,__PT_PSW(%r11) 800 mvc __PT_INT_CODE(12,%r11),__LC_SUBCHANNEL_ID 801 xc __PT_FLAGS(8,%r11),__PT_FLAGS(%r11) 802 TSTMSK __LC_CPU_FLAGS,_CIF_IGNORE_IRQ 803 jo .Lio_restore 804 TRACE_IRQS_OFF 805 xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15) 806.Lio_loop: 807 lgr %r2,%r11 # pass pointer to pt_regs 808 lghi %r3,IO_INTERRUPT 809 tm __PT_INT_CODE+8(%r11),0x80 # adapter interrupt ? 810 jz .Lio_call 811 lghi %r3,THIN_INTERRUPT 812.Lio_call: 813 brasl %r14,do_IRQ 814 TSTMSK __LC_MACHINE_FLAGS,MACHINE_FLAG_LPAR 815 jz .Lio_return 816 tpi 0 817 jz .Lio_return 818 mvc __PT_INT_CODE(12,%r11),__LC_SUBCHANNEL_ID 819 j .Lio_loop 820.Lio_return: 821 LOCKDEP_SYS_EXIT 822 TRACE_IRQS_ON 823.Lio_tif: 824 TSTMSK __TI_flags(%r12),_TIF_WORK 825 jnz .Lio_work # there is work to do (signals etc.) 826 TSTMSK __LC_CPU_FLAGS,_CIF_WORK 827 jnz .Lio_work 828.Lio_restore: 829 lg %r14,__LC_VDSO_PER_CPU 830 lmg %r0,%r10,__PT_R0(%r11) 831 mvc __LC_RETURN_PSW(16),__PT_PSW(%r11) 832 tm __PT_PSW+1(%r11),0x01 # returning to user ? 833 jno .Lio_exit_kernel 834 BPEXIT __TI_flags(%r12),_TIF_ISOLATE_BP 835.Lio_exit_timer: 836 stpt __LC_EXIT_TIMER 837 mvc __VDSO_ECTG_BASE(16,%r14),__LC_EXIT_TIMER 838.Lio_exit_kernel: 839 lmg %r11,%r15,__PT_R11(%r11) 840 lpswe __LC_RETURN_PSW 841.Lio_done: 842 843# 844# There is work todo, find out in which context we have been interrupted: 845# 1) if we return to user space we can do all _TIF_WORK work 846# 2) if we return to kernel code and kvm is enabled check if we need to 847# modify the psw to leave SIE 848# 3) if we return to kernel code and preemptive scheduling is enabled check 849# the preemption counter and if it is zero call preempt_schedule_irq 850# Before any work can be done, a switch to the kernel stack is required. 851# 852.Lio_work: 853 tm __PT_PSW+1(%r11),0x01 # returning to user ? 854 jo .Lio_work_user # yes -> do resched & signal 855#ifdef CONFIG_PREEMPT 856 # check for preemptive scheduling 857 icm %r0,15,__LC_PREEMPT_COUNT 858 jnz .Lio_restore # preemption is disabled 859 TSTMSK __TI_flags(%r12),_TIF_NEED_RESCHED 860 jno .Lio_restore 861 # switch to kernel stack 862 lg %r1,__PT_R15(%r11) 863 aghi %r1,-(STACK_FRAME_OVERHEAD + __PT_SIZE) 864 mvc STACK_FRAME_OVERHEAD(__PT_SIZE,%r1),0(%r11) 865 xc __SF_BACKCHAIN(8,%r1),__SF_BACKCHAIN(%r1) 866 la %r11,STACK_FRAME_OVERHEAD(%r1) 867 lgr %r15,%r1 868 # TRACE_IRQS_ON already done at .Lio_return, call 869 # TRACE_IRQS_OFF to keep things symmetrical 870 TRACE_IRQS_OFF 871 brasl %r14,preempt_schedule_irq 872 j .Lio_return 873#else 874 j .Lio_restore 875#endif 876 877# 878# Need to do work before returning to userspace, switch to kernel stack 879# 880.Lio_work_user: 881 lg %r1,__LC_KERNEL_STACK 882 mvc STACK_FRAME_OVERHEAD(__PT_SIZE,%r1),0(%r11) 883 xc __SF_BACKCHAIN(8,%r1),__SF_BACKCHAIN(%r1) 884 la %r11,STACK_FRAME_OVERHEAD(%r1) 885 lgr %r15,%r1 886 887# 888# One of the work bits is on. Find out which one. 889# 890.Lio_work_tif: 891 TSTMSK __LC_CPU_FLAGS,_CIF_MCCK_PENDING 892 jo .Lio_mcck_pending 893 TSTMSK __TI_flags(%r12),_TIF_NEED_RESCHED 894 jo .Lio_reschedule 895#ifdef CONFIG_LIVEPATCH 896 TSTMSK __TI_flags(%r12),_TIF_PATCH_PENDING 897 jo .Lio_patch_pending 898#endif 899 TSTMSK __TI_flags(%r12),_TIF_SIGPENDING 900 jo .Lio_sigpending 901 TSTMSK __TI_flags(%r12),_TIF_NOTIFY_RESUME 902 jo .Lio_notify_resume 903 TSTMSK __TI_flags(%r12),_TIF_GUARDED_STORAGE 904 jo .Lio_guarded_storage 905 TSTMSK __LC_CPU_FLAGS,_CIF_FPU 906 jo .Lio_vxrs 907 TSTMSK __LC_CPU_FLAGS,(_CIF_ASCE_PRIMARY|_CIF_ASCE_SECONDARY) 908 jnz .Lio_asce 909 j .Lio_return # beware of critical section cleanup 910 911# 912# _CIF_MCCK_PENDING is set, call handler 913# 914.Lio_mcck_pending: 915 # TRACE_IRQS_ON already done at .Lio_return 916 brasl %r14,s390_handle_mcck # TIF bit will be cleared by handler 917 TRACE_IRQS_OFF 918 j .Lio_return 919 920# 921# _CIF_ASCE_PRIMARY and/or CIF_ASCE_SECONDARY set, load user space asce 922# 923.Lio_asce: 924 ni __LC_CPU_FLAGS+7,255-_CIF_ASCE_SECONDARY 925 lctlg %c7,%c7,__LC_VDSO_ASCE # load secondary asce 926 TSTMSK __LC_CPU_FLAGS,_CIF_ASCE_PRIMARY 927 jz .Lio_return 928#ifndef CONFIG_HAVE_MARCH_Z10_FEATURES 929 tm __LC_STFLE_FAC_LIST+3,0x10 # has MVCOS ? 930 jnz .Lio_set_fs_fixup 931 ni __LC_CPU_FLAGS+7,255-_CIF_ASCE_PRIMARY 932 lctlg %c1,%c1,__LC_USER_ASCE # load primary asce 933 j .Lio_return 934.Lio_set_fs_fixup: 935#endif 936 larl %r14,.Lio_return 937 jg set_fs_fixup 938 939# 940# CIF_FPU is set, restore floating-point controls and floating-point registers. 941# 942.Lio_vxrs: 943 larl %r14,.Lio_return 944 jg load_fpu_regs 945 946# 947# _TIF_GUARDED_STORAGE is set, call guarded_storage_load 948# 949.Lio_guarded_storage: 950 # TRACE_IRQS_ON already done at .Lio_return 951 ssm __LC_SVC_NEW_PSW # reenable interrupts 952 lgr %r2,%r11 # pass pointer to pt_regs 953 brasl %r14,gs_load_bc_cb 954 ssm __LC_PGM_NEW_PSW # disable I/O and ext. interrupts 955 TRACE_IRQS_OFF 956 j .Lio_return 957 958# 959# _TIF_NEED_RESCHED is set, call schedule 960# 961.Lio_reschedule: 962 # TRACE_IRQS_ON already done at .Lio_return 963 ssm __LC_SVC_NEW_PSW # reenable interrupts 964 brasl %r14,schedule # call scheduler 965 ssm __LC_PGM_NEW_PSW # disable I/O and ext. interrupts 966 TRACE_IRQS_OFF 967 j .Lio_return 968 969# 970# _TIF_PATCH_PENDING is set, call klp_update_patch_state 971# 972#ifdef CONFIG_LIVEPATCH 973.Lio_patch_pending: 974 lg %r2,__LC_CURRENT # pass pointer to task struct 975 larl %r14,.Lio_return 976 jg klp_update_patch_state 977#endif 978 979# 980# _TIF_SIGPENDING or is set, call do_signal 981# 982.Lio_sigpending: 983 # TRACE_IRQS_ON already done at .Lio_return 984 ssm __LC_SVC_NEW_PSW # reenable interrupts 985 lgr %r2,%r11 # pass pointer to pt_regs 986 brasl %r14,do_signal 987 ssm __LC_PGM_NEW_PSW # disable I/O and ext. interrupts 988 TRACE_IRQS_OFF 989 j .Lio_return 990 991# 992# _TIF_NOTIFY_RESUME or is set, call do_notify_resume 993# 994.Lio_notify_resume: 995 # TRACE_IRQS_ON already done at .Lio_return 996 ssm __LC_SVC_NEW_PSW # reenable interrupts 997 lgr %r2,%r11 # pass pointer to pt_regs 998 brasl %r14,do_notify_resume 999 ssm __LC_PGM_NEW_PSW # disable I/O and ext. interrupts 1000 TRACE_IRQS_OFF 1001 j .Lio_return 1002 1003/* 1004 * External interrupt handler routine 1005 */ 1006ENTRY(ext_int_handler) 1007 STCK __LC_INT_CLOCK 1008 stpt __LC_ASYNC_ENTER_TIMER 1009 BPOFF 1010 stmg %r8,%r15,__LC_SAVE_AREA_ASYNC 1011 lg %r12,__LC_CURRENT 1012 larl %r13,cleanup_critical 1013 lmg %r8,%r9,__LC_EXT_OLD_PSW 1014 SWITCH_ASYNC __LC_SAVE_AREA_ASYNC,__LC_ASYNC_ENTER_TIMER 1015 stmg %r0,%r7,__PT_R0(%r11) 1016 # clear user controlled registers to prevent speculative use 1017 xgr %r0,%r0 1018 xgr %r1,%r1 1019 xgr %r2,%r2 1020 xgr %r3,%r3 1021 xgr %r4,%r4 1022 xgr %r5,%r5 1023 xgr %r6,%r6 1024 xgr %r7,%r7 1025 xgr %r10,%r10 1026 mvc __PT_R8(64,%r11),__LC_SAVE_AREA_ASYNC 1027 stmg %r8,%r9,__PT_PSW(%r11) 1028 lghi %r1,__LC_EXT_PARAMS2 1029 mvc __PT_INT_CODE(4,%r11),__LC_EXT_CPU_ADDR 1030 mvc __PT_INT_PARM(4,%r11),__LC_EXT_PARAMS 1031 mvc __PT_INT_PARM_LONG(8,%r11),0(%r1) 1032 xc __PT_FLAGS(8,%r11),__PT_FLAGS(%r11) 1033 TSTMSK __LC_CPU_FLAGS,_CIF_IGNORE_IRQ 1034 jo .Lio_restore 1035 TRACE_IRQS_OFF 1036 xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15) 1037 lgr %r2,%r11 # pass pointer to pt_regs 1038 lghi %r3,EXT_INTERRUPT 1039 brasl %r14,do_IRQ 1040 j .Lio_return 1041 1042/* 1043 * Load idle PSW. The second "half" of this function is in .Lcleanup_idle. 1044 */ 1045ENTRY(psw_idle) 1046 stg %r3,__SF_EMPTY(%r15) 1047 larl %r1,.Lpsw_idle_lpsw+4 1048 stg %r1,__SF_EMPTY+8(%r15) 1049#ifdef CONFIG_SMP 1050 larl %r1,smp_cpu_mtid 1051 llgf %r1,0(%r1) 1052 ltgr %r1,%r1 1053 jz .Lpsw_idle_stcctm 1054 .insn rsy,0xeb0000000017,%r1,5,__SF_EMPTY+16(%r15) 1055.Lpsw_idle_stcctm: 1056#endif 1057 oi __LC_CPU_FLAGS+7,_CIF_ENABLED_WAIT 1058 BPON 1059 STCK __CLOCK_IDLE_ENTER(%r2) 1060 stpt __TIMER_IDLE_ENTER(%r2) 1061.Lpsw_idle_lpsw: 1062 lpswe __SF_EMPTY(%r15) 1063 BR_R1USE_R14 1064.Lpsw_idle_end: 1065 1066/* 1067 * Store floating-point controls and floating-point or vector register 1068 * depending whether the vector facility is available. A critical section 1069 * cleanup assures that the registers are stored even if interrupted for 1070 * some other work. The CIF_FPU flag is set to trigger a lazy restore 1071 * of the register contents at return from io or a system call. 1072 */ 1073ENTRY(save_fpu_regs) 1074 lg %r2,__LC_CURRENT 1075 aghi %r2,__TASK_thread 1076 TSTMSK __LC_CPU_FLAGS,_CIF_FPU 1077 jo .Lsave_fpu_regs_exit 1078 stfpc __THREAD_FPU_fpc(%r2) 1079 lg %r3,__THREAD_FPU_regs(%r2) 1080 TSTMSK __LC_MACHINE_FLAGS,MACHINE_FLAG_VX 1081 jz .Lsave_fpu_regs_fp # no -> store FP regs 1082 VSTM %v0,%v15,0,%r3 # vstm 0,15,0(3) 1083 VSTM %v16,%v31,256,%r3 # vstm 16,31,256(3) 1084 j .Lsave_fpu_regs_done # -> set CIF_FPU flag 1085.Lsave_fpu_regs_fp: 1086 std 0,0(%r3) 1087 std 1,8(%r3) 1088 std 2,16(%r3) 1089 std 3,24(%r3) 1090 std 4,32(%r3) 1091 std 5,40(%r3) 1092 std 6,48(%r3) 1093 std 7,56(%r3) 1094 std 8,64(%r3) 1095 std 9,72(%r3) 1096 std 10,80(%r3) 1097 std 11,88(%r3) 1098 std 12,96(%r3) 1099 std 13,104(%r3) 1100 std 14,112(%r3) 1101 std 15,120(%r3) 1102.Lsave_fpu_regs_done: 1103 oi __LC_CPU_FLAGS+7,_CIF_FPU 1104.Lsave_fpu_regs_exit: 1105 BR_R1USE_R14 1106.Lsave_fpu_regs_end: 1107EXPORT_SYMBOL(save_fpu_regs) 1108 1109/* 1110 * Load floating-point controls and floating-point or vector registers. 1111 * A critical section cleanup assures that the register contents are 1112 * loaded even if interrupted for some other work. 1113 * 1114 * There are special calling conventions to fit into sysc and io return work: 1115 * %r15: <kernel stack> 1116 * The function requires: 1117 * %r4 1118 */ 1119load_fpu_regs: 1120 lg %r4,__LC_CURRENT 1121 aghi %r4,__TASK_thread 1122 TSTMSK __LC_CPU_FLAGS,_CIF_FPU 1123 jno .Lload_fpu_regs_exit 1124 lfpc __THREAD_FPU_fpc(%r4) 1125 TSTMSK __LC_MACHINE_FLAGS,MACHINE_FLAG_VX 1126 lg %r4,__THREAD_FPU_regs(%r4) # %r4 <- reg save area 1127 jz .Lload_fpu_regs_fp # -> no VX, load FP regs 1128 VLM %v0,%v15,0,%r4 1129 VLM %v16,%v31,256,%r4 1130 j .Lload_fpu_regs_done 1131.Lload_fpu_regs_fp: 1132 ld 0,0(%r4) 1133 ld 1,8(%r4) 1134 ld 2,16(%r4) 1135 ld 3,24(%r4) 1136 ld 4,32(%r4) 1137 ld 5,40(%r4) 1138 ld 6,48(%r4) 1139 ld 7,56(%r4) 1140 ld 8,64(%r4) 1141 ld 9,72(%r4) 1142 ld 10,80(%r4) 1143 ld 11,88(%r4) 1144 ld 12,96(%r4) 1145 ld 13,104(%r4) 1146 ld 14,112(%r4) 1147 ld 15,120(%r4) 1148.Lload_fpu_regs_done: 1149 ni __LC_CPU_FLAGS+7,255-_CIF_FPU 1150.Lload_fpu_regs_exit: 1151 BR_R1USE_R14 1152.Lload_fpu_regs_end: 1153 1154.L__critical_end: 1155 1156/* 1157 * Machine check handler routines 1158 */ 1159ENTRY(mcck_int_handler) 1160 STCK __LC_MCCK_CLOCK 1161 BPOFF 1162 la %r1,4095 # validate r1 1163 spt __LC_CPU_TIMER_SAVE_AREA-4095(%r1) # validate cpu timer 1164 sckc __LC_CLOCK_COMPARATOR # validate comparator 1165 lam %a0,%a15,__LC_AREGS_SAVE_AREA-4095(%r1) # validate acrs 1166 lmg %r0,%r15,__LC_GPREGS_SAVE_AREA-4095(%r1)# validate gprs 1167 lg %r12,__LC_CURRENT 1168 larl %r13,cleanup_critical 1169 lmg %r8,%r9,__LC_MCK_OLD_PSW 1170 TSTMSK __LC_MCCK_CODE,MCCK_CODE_SYSTEM_DAMAGE 1171 jo .Lmcck_panic # yes -> rest of mcck code invalid 1172 TSTMSK __LC_MCCK_CODE,MCCK_CODE_CR_VALID 1173 jno .Lmcck_panic # control registers invalid -> panic 1174 la %r14,4095 1175 lctlg %c0,%c15,__LC_CREGS_SAVE_AREA-4095(%r14) # validate ctl regs 1176 ptlb 1177 lg %r11,__LC_MCESAD-4095(%r14) # extended machine check save area 1178 nill %r11,0xfc00 # MCESA_ORIGIN_MASK 1179 TSTMSK __LC_CREGS_SAVE_AREA+16-4095(%r14),CR2_GUARDED_STORAGE 1180 jno 0f 1181 TSTMSK __LC_MCCK_CODE,MCCK_CODE_GS_VALID 1182 jno 0f 1183 .insn rxy,0xe3000000004d,0,__MCESA_GS_SAVE_AREA(%r11) # LGSC 11840: l %r14,__LC_FP_CREG_SAVE_AREA-4095(%r14) 1185 TSTMSK __LC_MCCK_CODE,MCCK_CODE_FC_VALID 1186 jo 0f 1187 sr %r14,%r14 11880: sfpc %r14 1189 TSTMSK __LC_MACHINE_FLAGS,MACHINE_FLAG_VX 1190 jo 0f 1191 lghi %r14,__LC_FPREGS_SAVE_AREA 1192 ld %f0,0(%r14) 1193 ld %f1,8(%r14) 1194 ld %f2,16(%r14) 1195 ld %f3,24(%r14) 1196 ld %f4,32(%r14) 1197 ld %f5,40(%r14) 1198 ld %f6,48(%r14) 1199 ld %f7,56(%r14) 1200 ld %f8,64(%r14) 1201 ld %f9,72(%r14) 1202 ld %f10,80(%r14) 1203 ld %f11,88(%r14) 1204 ld %f12,96(%r14) 1205 ld %f13,104(%r14) 1206 ld %f14,112(%r14) 1207 ld %f15,120(%r14) 1208 j 1f 12090: VLM %v0,%v15,0,%r11 1210 VLM %v16,%v31,256,%r11 12111: lghi %r14,__LC_CPU_TIMER_SAVE_AREA 1212 mvc __LC_MCCK_ENTER_TIMER(8),0(%r14) 1213 TSTMSK __LC_MCCK_CODE,MCCK_CODE_CPU_TIMER_VALID 1214 jo 3f 1215 la %r14,__LC_SYNC_ENTER_TIMER 1216 clc 0(8,%r14),__LC_ASYNC_ENTER_TIMER 1217 jl 0f 1218 la %r14,__LC_ASYNC_ENTER_TIMER 12190: clc 0(8,%r14),__LC_EXIT_TIMER 1220 jl 1f 1221 la %r14,__LC_EXIT_TIMER 12221: clc 0(8,%r14),__LC_LAST_UPDATE_TIMER 1223 jl 2f 1224 la %r14,__LC_LAST_UPDATE_TIMER 12252: spt 0(%r14) 1226 mvc __LC_MCCK_ENTER_TIMER(8),0(%r14) 12273: TSTMSK __LC_MCCK_CODE,MCCK_CODE_PSW_MWP_VALID 1228 jno .Lmcck_panic 1229 tmhh %r8,0x0001 # interrupting from user ? 1230 jnz 4f 1231 TSTMSK __LC_MCCK_CODE,MCCK_CODE_PSW_IA_VALID 1232 jno .Lmcck_panic 12334: SWITCH_ASYNC __LC_GPREGS_SAVE_AREA+64,__LC_MCCK_ENTER_TIMER 1234.Lmcck_skip: 1235 lghi %r14,__LC_GPREGS_SAVE_AREA+64 1236 stmg %r0,%r7,__PT_R0(%r11) 1237 # clear user controlled registers to prevent speculative use 1238 xgr %r0,%r0 1239 xgr %r1,%r1 1240 xgr %r2,%r2 1241 xgr %r3,%r3 1242 xgr %r4,%r4 1243 xgr %r5,%r5 1244 xgr %r6,%r6 1245 xgr %r7,%r7 1246 xgr %r10,%r10 1247 mvc __PT_R8(64,%r11),0(%r14) 1248 stmg %r8,%r9,__PT_PSW(%r11) 1249 xc __PT_FLAGS(8,%r11),__PT_FLAGS(%r11) 1250 xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15) 1251 lgr %r2,%r11 # pass pointer to pt_regs 1252 brasl %r14,s390_do_machine_check 1253 tm __PT_PSW+1(%r11),0x01 # returning to user ? 1254 jno .Lmcck_return 1255 lg %r1,__LC_KERNEL_STACK # switch to kernel stack 1256 mvc STACK_FRAME_OVERHEAD(__PT_SIZE,%r1),0(%r11) 1257 xc __SF_BACKCHAIN(8,%r1),__SF_BACKCHAIN(%r1) 1258 la %r11,STACK_FRAME_OVERHEAD(%r1) 1259 lgr %r15,%r1 1260 ssm __LC_PGM_NEW_PSW # turn dat on, keep irqs off 1261 TSTMSK __LC_CPU_FLAGS,_CIF_MCCK_PENDING 1262 jno .Lmcck_return 1263 TRACE_IRQS_OFF 1264 brasl %r14,s390_handle_mcck 1265 TRACE_IRQS_ON 1266.Lmcck_return: 1267 lg %r14,__LC_VDSO_PER_CPU 1268 lmg %r0,%r10,__PT_R0(%r11) 1269 mvc __LC_RETURN_MCCK_PSW(16),__PT_PSW(%r11) # move return PSW 1270 tm __LC_RETURN_MCCK_PSW+1,0x01 # returning to user ? 1271 jno 0f 1272 BPEXIT __TI_flags(%r12),_TIF_ISOLATE_BP 1273 stpt __LC_EXIT_TIMER 1274 mvc __VDSO_ECTG_BASE(16,%r14),__LC_EXIT_TIMER 12750: lmg %r11,%r15,__PT_R11(%r11) 1276 lpswe __LC_RETURN_MCCK_PSW 1277 1278.Lmcck_panic: 1279 lg %r15,__LC_PANIC_STACK 1280 la %r11,STACK_FRAME_OVERHEAD(%r15) 1281 j .Lmcck_skip 1282 1283# 1284# PSW restart interrupt handler 1285# 1286ENTRY(restart_int_handler) 1287 TSTMSK __LC_MACHINE_FLAGS,MACHINE_FLAG_LPP 1288 jz 0f 1289 .insn s,0xb2800000,__LC_LPP 12900: stg %r15,__LC_SAVE_AREA_RESTART 1291 lg %r15,__LC_RESTART_STACK 1292 aghi %r15,-__PT_SIZE # create pt_regs on stack 1293 xc 0(__PT_SIZE,%r15),0(%r15) 1294 stmg %r0,%r14,__PT_R0(%r15) 1295 mvc __PT_R15(8,%r15),__LC_SAVE_AREA_RESTART 1296 mvc __PT_PSW(16,%r15),__LC_RST_OLD_PSW # store restart old psw 1297 aghi %r15,-STACK_FRAME_OVERHEAD # create stack frame on stack 1298 xc 0(STACK_FRAME_OVERHEAD,%r15),0(%r15) 1299 lg %r1,__LC_RESTART_FN # load fn, parm & source cpu 1300 lg %r2,__LC_RESTART_DATA 1301 lg %r3,__LC_RESTART_SOURCE 1302 ltgr %r3,%r3 # test source cpu address 1303 jm 1f # negative -> skip source stop 13040: sigp %r4,%r3,SIGP_SENSE # sigp sense to source cpu 1305 brc 10,0b # wait for status stored 13061: basr %r14,%r1 # call function 1307 stap __SF_EMPTY(%r15) # store cpu address 1308 llgh %r3,__SF_EMPTY(%r15) 13092: sigp %r4,%r3,SIGP_STOP # sigp stop to current cpu 1310 brc 2,2b 13113: j 3b 1312 1313 .section .kprobes.text, "ax" 1314 1315#ifdef CONFIG_CHECK_STACK 1316/* 1317 * The synchronous or the asynchronous stack overflowed. We are dead. 1318 * No need to properly save the registers, we are going to panic anyway. 1319 * Setup a pt_regs so that show_trace can provide a good call trace. 1320 */ 1321stack_overflow: 1322 lg %r15,__LC_PANIC_STACK # change to panic stack 1323 la %r11,STACK_FRAME_OVERHEAD(%r15) 1324 stmg %r0,%r7,__PT_R0(%r11) 1325 stmg %r8,%r9,__PT_PSW(%r11) 1326 mvc __PT_R8(64,%r11),0(%r14) 1327 stg %r10,__PT_ORIG_GPR2(%r11) # store last break to orig_gpr2 1328 xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15) 1329 lgr %r2,%r11 # pass pointer to pt_regs 1330 jg kernel_stack_overflow 1331#endif 1332 1333cleanup_critical: 1334#if IS_ENABLED(CONFIG_KVM) 1335 clg %r9,BASED(.Lcleanup_table_sie) # .Lsie_gmap 1336 jl 0f 1337 clg %r9,BASED(.Lcleanup_table_sie+8)# .Lsie_done 1338 jl .Lcleanup_sie 1339#endif 1340 clg %r9,BASED(.Lcleanup_table) # system_call 1341 jl 0f 1342 clg %r9,BASED(.Lcleanup_table+8) # .Lsysc_do_svc 1343 jl .Lcleanup_system_call 1344 clg %r9,BASED(.Lcleanup_table+16) # .Lsysc_tif 1345 jl 0f 1346 clg %r9,BASED(.Lcleanup_table+24) # .Lsysc_restore 1347 jl .Lcleanup_sysc_tif 1348 clg %r9,BASED(.Lcleanup_table+32) # .Lsysc_done 1349 jl .Lcleanup_sysc_restore 1350 clg %r9,BASED(.Lcleanup_table+40) # .Lio_tif 1351 jl 0f 1352 clg %r9,BASED(.Lcleanup_table+48) # .Lio_restore 1353 jl .Lcleanup_io_tif 1354 clg %r9,BASED(.Lcleanup_table+56) # .Lio_done 1355 jl .Lcleanup_io_restore 1356 clg %r9,BASED(.Lcleanup_table+64) # psw_idle 1357 jl 0f 1358 clg %r9,BASED(.Lcleanup_table+72) # .Lpsw_idle_end 1359 jl .Lcleanup_idle 1360 clg %r9,BASED(.Lcleanup_table+80) # save_fpu_regs 1361 jl 0f 1362 clg %r9,BASED(.Lcleanup_table+88) # .Lsave_fpu_regs_end 1363 jl .Lcleanup_save_fpu_regs 1364 clg %r9,BASED(.Lcleanup_table+96) # load_fpu_regs 1365 jl 0f 1366 clg %r9,BASED(.Lcleanup_table+104) # .Lload_fpu_regs_end 1367 jl .Lcleanup_load_fpu_regs 13680: BR_R11USE_R14 1369 1370 .align 8 1371.Lcleanup_table: 1372 .quad system_call 1373 .quad .Lsysc_do_svc 1374 .quad .Lsysc_tif 1375 .quad .Lsysc_restore 1376 .quad .Lsysc_done 1377 .quad .Lio_tif 1378 .quad .Lio_restore 1379 .quad .Lio_done 1380 .quad psw_idle 1381 .quad .Lpsw_idle_end 1382 .quad save_fpu_regs 1383 .quad .Lsave_fpu_regs_end 1384 .quad load_fpu_regs 1385 .quad .Lload_fpu_regs_end 1386 1387#if IS_ENABLED(CONFIG_KVM) 1388.Lcleanup_table_sie: 1389 .quad .Lsie_gmap 1390 .quad .Lsie_done 1391 1392.Lcleanup_sie: 1393 cghi %r11,__LC_SAVE_AREA_ASYNC #Is this in normal interrupt? 1394 je 1f 1395 slg %r9,BASED(.Lsie_crit_mcck_start) 1396 clg %r9,BASED(.Lsie_crit_mcck_length) 1397 jh 1f 1398 oi __LC_CPU_FLAGS+7, _CIF_MCCK_GUEST 13991: BPENTER __SF_EMPTY+24(%r15),(_TIF_ISOLATE_BP|_TIF_ISOLATE_BP_GUEST) 1400 lg %r9,__SF_EMPTY(%r15) # get control block pointer 1401 ni __SIE_PROG0C+3(%r9),0xfe # no longer in SIE 1402 lctlg %c1,%c1,__LC_USER_ASCE # load primary asce 1403 larl %r9,sie_exit # skip forward to sie_exit 1404 BR_R11USE_R14 1405#endif 1406 1407.Lcleanup_system_call: 1408 # check if stpt has been executed 1409 clg %r9,BASED(.Lcleanup_system_call_insn) 1410 jh 0f 1411 mvc __LC_SYNC_ENTER_TIMER(8),__LC_ASYNC_ENTER_TIMER 1412 cghi %r11,__LC_SAVE_AREA_ASYNC 1413 je 0f 1414 mvc __LC_SYNC_ENTER_TIMER(8),__LC_MCCK_ENTER_TIMER 14150: # check if stmg has been executed 1416 clg %r9,BASED(.Lcleanup_system_call_insn+8) 1417 jh 0f 1418 mvc __LC_SAVE_AREA_SYNC(64),0(%r11) 14190: # check if base register setup + TIF bit load has been done 1420 clg %r9,BASED(.Lcleanup_system_call_insn+16) 1421 jhe 0f 1422 # set up saved register r12 task struct pointer 1423 stg %r12,32(%r11) 1424 # set up saved register r13 __TASK_thread offset 1425 mvc 40(8,%r11),BASED(.Lcleanup_system_call_const) 14260: # check if the user time update has been done 1427 clg %r9,BASED(.Lcleanup_system_call_insn+24) 1428 jh 0f 1429 lg %r15,__LC_EXIT_TIMER 1430 slg %r15,__LC_SYNC_ENTER_TIMER 1431 alg %r15,__LC_USER_TIMER 1432 stg %r15,__LC_USER_TIMER 14330: # check if the system time update has been done 1434 clg %r9,BASED(.Lcleanup_system_call_insn+32) 1435 jh 0f 1436 lg %r15,__LC_LAST_UPDATE_TIMER 1437 slg %r15,__LC_EXIT_TIMER 1438 alg %r15,__LC_SYSTEM_TIMER 1439 stg %r15,__LC_SYSTEM_TIMER 14400: # update accounting time stamp 1441 mvc __LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER 1442 # set up saved register r11 1443 lg %r15,__LC_KERNEL_STACK 1444 la %r9,STACK_FRAME_OVERHEAD(%r15) 1445 stg %r9,24(%r11) # r11 pt_regs pointer 1446 # fill pt_regs 1447 mvc __PT_R8(64,%r9),__LC_SAVE_AREA_SYNC 1448 stmg %r0,%r7,__PT_R0(%r9) 1449 mvc __PT_PSW(16,%r9),__LC_SVC_OLD_PSW 1450 mvc __PT_INT_CODE(4,%r9),__LC_SVC_ILC 1451 xc __PT_FLAGS(8,%r9),__PT_FLAGS(%r9) 1452 mvi __PT_FLAGS+7(%r9),_PIF_SYSCALL 1453 # setup saved register r15 1454 stg %r15,56(%r11) # r15 stack pointer 1455 # set new psw address and exit 1456 larl %r9,.Lsysc_do_svc 1457 BR_R11USE_R14 1458.Lcleanup_system_call_insn: 1459 .quad system_call 1460 .quad .Lsysc_stmg 1461 .quad .Lsysc_per 1462 .quad .Lsysc_vtime+36 1463 .quad .Lsysc_vtime+42 1464.Lcleanup_system_call_const: 1465 .quad __TASK_thread 1466 1467.Lcleanup_sysc_tif: 1468 larl %r9,.Lsysc_tif 1469 BR_R11USE_R14 1470 1471.Lcleanup_sysc_restore: 1472 # check if stpt has been executed 1473 clg %r9,BASED(.Lcleanup_sysc_restore_insn) 1474 jh 0f 1475 mvc __LC_EXIT_TIMER(8),__LC_ASYNC_ENTER_TIMER 1476 cghi %r11,__LC_SAVE_AREA_ASYNC 1477 je 0f 1478 mvc __LC_EXIT_TIMER(8),__LC_MCCK_ENTER_TIMER 14790: clg %r9,BASED(.Lcleanup_sysc_restore_insn+8) 1480 je 1f 1481 lg %r9,24(%r11) # get saved pointer to pt_regs 1482 mvc __LC_RETURN_PSW(16),__PT_PSW(%r9) 1483 mvc 0(64,%r11),__PT_R8(%r9) 1484 lmg %r0,%r7,__PT_R0(%r9) 14851: lmg %r8,%r9,__LC_RETURN_PSW 1486 BR_R11USE_R14 1487.Lcleanup_sysc_restore_insn: 1488 .quad .Lsysc_exit_timer 1489 .quad .Lsysc_done - 4 1490 1491.Lcleanup_io_tif: 1492 larl %r9,.Lio_tif 1493 BR_R11USE_R14 1494 1495.Lcleanup_io_restore: 1496 # check if stpt has been executed 1497 clg %r9,BASED(.Lcleanup_io_restore_insn) 1498 jh 0f 1499 mvc __LC_EXIT_TIMER(8),__LC_MCCK_ENTER_TIMER 15000: clg %r9,BASED(.Lcleanup_io_restore_insn+8) 1501 je 1f 1502 lg %r9,24(%r11) # get saved r11 pointer to pt_regs 1503 mvc __LC_RETURN_PSW(16),__PT_PSW(%r9) 1504 mvc 0(64,%r11),__PT_R8(%r9) 1505 lmg %r0,%r7,__PT_R0(%r9) 15061: lmg %r8,%r9,__LC_RETURN_PSW 1507 BR_R11USE_R14 1508.Lcleanup_io_restore_insn: 1509 .quad .Lio_exit_timer 1510 .quad .Lio_done - 4 1511 1512.Lcleanup_idle: 1513 ni __LC_CPU_FLAGS+7,255-_CIF_ENABLED_WAIT 1514 # copy interrupt clock & cpu timer 1515 mvc __CLOCK_IDLE_EXIT(8,%r2),__LC_INT_CLOCK 1516 mvc __TIMER_IDLE_EXIT(8,%r2),__LC_ASYNC_ENTER_TIMER 1517 cghi %r11,__LC_SAVE_AREA_ASYNC 1518 je 0f 1519 mvc __CLOCK_IDLE_EXIT(8,%r2),__LC_MCCK_CLOCK 1520 mvc __TIMER_IDLE_EXIT(8,%r2),__LC_MCCK_ENTER_TIMER 15210: # check if stck & stpt have been executed 1522 clg %r9,BASED(.Lcleanup_idle_insn) 1523 jhe 1f 1524 mvc __CLOCK_IDLE_ENTER(8,%r2),__CLOCK_IDLE_EXIT(%r2) 1525 mvc __TIMER_IDLE_ENTER(8,%r2),__TIMER_IDLE_EXIT(%r2) 15261: # calculate idle cycles 1527#ifdef CONFIG_SMP 1528 clg %r9,BASED(.Lcleanup_idle_insn) 1529 jl 3f 1530 larl %r1,smp_cpu_mtid 1531 llgf %r1,0(%r1) 1532 ltgr %r1,%r1 1533 jz 3f 1534 .insn rsy,0xeb0000000017,%r1,5,__SF_EMPTY+80(%r15) 1535 larl %r3,mt_cycles 1536 ag %r3,__LC_PERCPU_OFFSET 1537 la %r4,__SF_EMPTY+16(%r15) 15382: lg %r0,0(%r3) 1539 slg %r0,0(%r4) 1540 alg %r0,64(%r4) 1541 stg %r0,0(%r3) 1542 la %r3,8(%r3) 1543 la %r4,8(%r4) 1544 brct %r1,2b 1545#endif 15463: # account system time going idle 1547 lg %r9,__LC_STEAL_TIMER 1548 alg %r9,__CLOCK_IDLE_ENTER(%r2) 1549 slg %r9,__LC_LAST_UPDATE_CLOCK 1550 stg %r9,__LC_STEAL_TIMER 1551 mvc __LC_LAST_UPDATE_CLOCK(8),__CLOCK_IDLE_EXIT(%r2) 1552 lg %r9,__LC_SYSTEM_TIMER 1553 alg %r9,__LC_LAST_UPDATE_TIMER 1554 slg %r9,__TIMER_IDLE_ENTER(%r2) 1555 stg %r9,__LC_SYSTEM_TIMER 1556 mvc __LC_LAST_UPDATE_TIMER(8),__TIMER_IDLE_EXIT(%r2) 1557 # prepare return psw 1558 nihh %r8,0xfcfd # clear irq & wait state bits 1559 lg %r9,48(%r11) # return from psw_idle 1560 BR_R11USE_R14 1561.Lcleanup_idle_insn: 1562 .quad .Lpsw_idle_lpsw 1563 1564.Lcleanup_save_fpu_regs: 1565 larl %r9,save_fpu_regs 1566 BR_R11USE_R14 1567 1568.Lcleanup_load_fpu_regs: 1569 larl %r9,load_fpu_regs 1570 BR_R11USE_R14 1571 1572/* 1573 * Integer constants 1574 */ 1575 .align 8 1576.Lcritical_start: 1577 .quad .L__critical_start 1578.Lcritical_length: 1579 .quad .L__critical_end - .L__critical_start 1580#if IS_ENABLED(CONFIG_KVM) 1581.Lsie_critical_start: 1582 .quad .Lsie_gmap 1583.Lsie_critical_length: 1584 .quad .Lsie_done - .Lsie_gmap 1585.Lsie_crit_mcck_start: 1586 .quad .Lsie_entry 1587.Lsie_crit_mcck_length: 1588 .quad .Lsie_skip - .Lsie_entry 1589#endif 1590 .section .rodata, "a" 1591#define SYSCALL(esame,emu) .long esame 1592 .globl sys_call_table 1593sys_call_table: 1594#include "asm/syscall_table.h" 1595#undef SYSCALL 1596 1597#ifdef CONFIG_COMPAT 1598 1599#define SYSCALL(esame,emu) .long emu 1600 .globl sys_call_table_emu 1601sys_call_table_emu: 1602#include "asm/syscall_table.h" 1603#undef SYSCALL 1604#endif 1605