| blob | 3f4d272577d343cc41904e10d57800efb1d2a5cc |
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 */
12 #include <linux/init.h>
13 #include <linux/linkage.h>
14 #include <asm/alternative-asm.h>
15 #include <asm/processor.h>
16 #include <asm/cache.h>
17 #include <asm/ctl_reg.h>
18 #include <asm/dwarf.h>
19 #include <asm/errno.h>
20 #include <asm/ptrace.h>
21 #include <asm/thread_info.h>
22 #include <asm/asm-offsets.h>
23 #include <asm/unistd.h>
24 #include <asm/page.h>
25 #include <asm/sigp.h>
26 #include <asm/irq.h>
27 #include <asm/vx-insn.h>
28 #include <asm/setup.h>
29 #include <asm/nmi.h>
30 #include <asm/export.h>
31 #include <asm/nospec-insn.h>
33 __PT_R0 = __PT_GPRS
34 __PT_R1 = __PT_GPRS + 8
35 __PT_R2 = __PT_GPRS + 16
36 __PT_R3 = __PT_GPRS + 24
37 __PT_R4 = __PT_GPRS + 32
38 __PT_R5 = __PT_GPRS + 40
39 __PT_R6 = __PT_GPRS + 48
40 __PT_R7 = __PT_GPRS + 56
41 __PT_R8 = __PT_GPRS + 64
42 __PT_R9 = __PT_GPRS + 72
43 __PT_R10 = __PT_GPRS + 80
44 __PT_R11 = __PT_GPRS + 88
45 __PT_R12 = __PT_GPRS + 96
46 __PT_R13 = __PT_GPRS + 104
47 __PT_R14 = __PT_GPRS + 112
48 __PT_R15 = __PT_GPRS + 120
50 STACK_SHIFT = PAGE_SHIFT + THREAD_SIZE_ORDER
51 STACK_SIZE = 1 << STACK_SHIFT
52 STACK_INIT = STACK_SIZE - STACK_FRAME_OVERHEAD - __PT_SIZE
54 _TIF_WORK = (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_NEED_RESCHED | \
55 _TIF_UPROBE | _TIF_GUARDED_STORAGE | _TIF_PATCH_PENDING)
56 _TIF_TRACE = (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | _TIF_SECCOMP | \
57 _TIF_SYSCALL_TRACEPOINT)
58 _CIF_WORK = (_CIF_MCCK_PENDING | _CIF_ASCE_PRIMARY | \
59 _CIF_ASCE_SECONDARY | _CIF_FPU)
60 _PIF_WORK = (_PIF_PER_TRAP | _PIF_SYSCALL_RESTART)
62 _LPP_OFFSET = __LC_LPP
64 #define BASED(name) name-cleanup_critical(%r13)
66 .macro TRACE_IRQS_ON
67 #ifdef CONFIG_TRACE_IRQFLAGS
68 basr %r2,%r0
69 brasl %r14,trace_hardirqs_on_caller
70 #endif
71 .endm
73 .macro TRACE_IRQS_OFF
74 #ifdef CONFIG_TRACE_IRQFLAGS
75 basr %r2,%r0
76 brasl %r14,trace_hardirqs_off_caller
77 #endif
78 .endm
80 .macro LOCKDEP_SYS_EXIT
81 #ifdef CONFIG_LOCKDEP
82 tm __PT_PSW+1(%r11),0x01 # returning to user ?
83 jz .+10
84 brasl %r14,lockdep_sys_exit
85 #endif
86 .endm
88 .macro CHECK_STACK savearea
89 #ifdef CONFIG_CHECK_STACK
90 tml %r15,STACK_SIZE - CONFIG_STACK_GUARD
91 lghi %r14,\savearea
92 jz stack_overflow
93 #endif
94 .endm
96 .macro CHECK_VMAP_STACK savearea,oklabel
97 #ifdef CONFIG_VMAP_STACK
98 lgr %r14,%r15
99 nill %r14,0x10000 - STACK_SIZE
100 oill %r14,STACK_INIT
101 clg %r14,__LC_KERNEL_STACK
102 je \oklabel
103 clg %r14,__LC_ASYNC_STACK
104 je \oklabel
105 clg %r14,__LC_NODAT_STACK
106 je \oklabel
107 clg %r14,__LC_RESTART_STACK
108 je \oklabel
109 lghi %r14,\savearea
110 j stack_overflow
111 #else
112 j \oklabel
113 #endif
114 .endm
116 .macro SWITCH_ASYNC savearea,timer
117 tmhh %r8,0x0001 # interrupting from user ?
118 jnz 1f
119 lgr %r14,%r9
120 slg %r14,BASED(.Lcritical_start)
121 clg %r14,BASED(.Lcritical_length)
122 jhe 0f
123 lghi %r11,\savearea # inside critical section, do cleanup
124 brasl %r14,cleanup_critical
125 tmhh %r8,0x0001 # retest problem state after cleanup
126 jnz 1f
127 0: lg %r14,__LC_ASYNC_STACK # are we already on the target stack?
128 slgr %r14,%r15
129 srag %r14,%r14,STACK_SHIFT
130 jnz 2f
131 CHECK_STACK \savearea
132 aghi %r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE)
133 j 3f
134 1: UPDATE_VTIME %r14,%r15,\timer
135 BPENTER __TI_flags(%r12),_TIF_ISOLATE_BP
136 2: lg %r15,__LC_ASYNC_STACK # load async stack
137 3: la %r11,STACK_FRAME_OVERHEAD(%r15)
138 .endm
140 .macro UPDATE_VTIME w1,w2,enter_timer
141 lg \w1,__LC_EXIT_TIMER
142 lg \w2,__LC_LAST_UPDATE_TIMER
143 slg \w1,\enter_timer
144 slg \w2,__LC_EXIT_TIMER
145 alg \w1,__LC_USER_TIMER
146 alg \w2,__LC_SYSTEM_TIMER
147 stg \w1,__LC_USER_TIMER
148 stg \w2,__LC_SYSTEM_TIMER
149 mvc __LC_LAST_UPDATE_TIMER(8),\enter_timer
150 .endm
152 .macro REENABLE_IRQS
153 stg %r8,__LC_RETURN_PSW
154 ni __LC_RETURN_PSW,0xbf
155 ssm __LC_RETURN_PSW
156 .endm
158 .macro STCK savearea
159 #ifdef CONFIG_HAVE_MARCH_Z9_109_FEATURES
160 .insn s,0xb27c0000,\savearea # store clock fast
161 #else
162 .insn s,0xb2050000,\savearea # store clock
163 #endif
164 .endm
166 /*
167 * The TSTMSK macro generates a test-under-mask instruction by
168 * calculating the memory offset for the specified mask value.
169 * Mask value can be any constant. The macro shifts the mask
170 * value to calculate the memory offset for the test-under-mask
171 * instruction.
172 */
173 .macro TSTMSK addr, mask, size=8, bytepos=0
174 .if (\bytepos < \size) && (\mask >> 8)
175 .if (\mask & 0xff)
176 .error "Mask exceeds byte boundary"
177 .endif
178 TSTMSK \addr, "(\mask >> 8)", \size, "(\bytepos + 1)"
179 .exitm
180 .endif
181 .ifeq \mask
182 .error "Mask must not be zero"
183 .endif
184 off = \size - \bytepos - 1
185 tm off+\addr, \mask
186 .endm
188 .macro BPOFF
189 ALTERNATIVE "", ".long 0xb2e8c000", 82
190 .endm
192 .macro BPON
193 ALTERNATIVE "", ".long 0xb2e8d000", 82
194 .endm
196 .macro BPENTER tif_ptr,tif_mask
197 ALTERNATIVE "TSTMSK \tif_ptr,\tif_mask; jz .+8; .long 0xb2e8d000", \
198 "", 82
199 .endm
201 .macro BPEXIT tif_ptr,tif_mask
202 TSTMSK \tif_ptr,\tif_mask
203 ALTERNATIVE "jz .+8; .long 0xb2e8c000", \
204 "jnz .+8; .long 0xb2e8d000", 82
205 .endm
207 GEN_BR_THUNK %r9
208 GEN_BR_THUNK %r14
209 GEN_BR_THUNK %r14,%r11
211 .section .kprobes.text, "ax"
212 .Ldummy:
213 /*
214 * This nop exists only in order to avoid that __switch_to starts at
215 * the beginning of the kprobes text section. In that case we would
216 * have several symbols at the same address. E.g. objdump would take
217 * an arbitrary symbol name when disassembling this code.
218 * With the added nop in between the __switch_to symbol is unique
219 * again.
220 */
221 nop 0
223 ENTRY(__bpon)
224 .globl __bpon
225 BPON
226 BR_EX %r14
227 ENDPROC(__bpon)
229 /*
230 * Scheduler resume function, called by switch_to
231 * gpr2 = (task_struct *) prev
232 * gpr3 = (task_struct *) next
233 * Returns:
234 * gpr2 = prev
235 */
236 ENTRY(__switch_to)
237 stmg %r6,%r15,__SF_GPRS(%r15) # store gprs of prev task
238 lghi %r4,__TASK_stack
239 lghi %r1,__TASK_thread
240 llill %r5,STACK_INIT
241 stg %r15,__THREAD_ksp(%r1,%r2) # store kernel stack of prev
242 lg %r15,0(%r4,%r3) # start of kernel stack of next
243 agr %r15,%r5 # end of kernel stack of next
244 stg %r3,__LC_CURRENT # store task struct of next
245 stg %r15,__LC_KERNEL_STACK # store end of kernel stack
246 lg %r15,__THREAD_ksp(%r1,%r3) # load kernel stack of next
247 aghi %r3,__TASK_pid
248 mvc __LC_CURRENT_PID(4,%r0),0(%r3) # store pid of next
249 lmg %r6,%r15,__SF_GPRS(%r15) # load gprs of next task
250 ALTERNATIVE "", ".insn s,0xb2800000,_LPP_OFFSET", 40
251 BR_EX %r14
252 ENDPROC(__switch_to)
254 .L__critical_start:
256 #if IS_ENABLED(CONFIG_KVM)
257 /*
258 * sie64a calling convention:
259 * %r2 pointer to sie control block
260 * %r3 guest register save area
261 */
262 ENTRY(sie64a)
263 stmg %r6,%r14,__SF_GPRS(%r15) # save kernel registers
264 lg %r12,__LC_CURRENT
265 stg %r2,__SF_SIE_CONTROL(%r15) # save control block pointer
266 stg %r3,__SF_SIE_SAVEAREA(%r15) # save guest register save area
267 xc __SF_SIE_REASON(8,%r15),__SF_SIE_REASON(%r15) # reason code = 0
268 mvc __SF_SIE_FLAGS(8,%r15),__TI_flags(%r12) # copy thread flags
269 TSTMSK __LC_CPU_FLAGS,_CIF_FPU # load guest fp/vx registers ?
270 jno .Lsie_load_guest_gprs
271 brasl %r14,load_fpu_regs # load guest fp/vx regs
272 .Lsie_load_guest_gprs:
273 lmg %r0,%r13,0(%r3) # load guest gprs 0-13
274 lg %r14,__LC_GMAP # get gmap pointer
275 ltgr %r14,%r14
276 jz .Lsie_gmap
277 lctlg %c1,%c1,__GMAP_ASCE(%r14) # load primary asce
278 .Lsie_gmap:
279 lg %r14,__SF_SIE_CONTROL(%r15) # get control block pointer
280 oi __SIE_PROG0C+3(%r14),1 # we are going into SIE now
281 tm __SIE_PROG20+3(%r14),3 # last exit...
282 jnz .Lsie_skip
283 TSTMSK __LC_CPU_FLAGS,_CIF_FPU
284 jo .Lsie_skip # exit if fp/vx regs changed
285 BPEXIT __SF_SIE_FLAGS(%r15),(_TIF_ISOLATE_BP|_TIF_ISOLATE_BP_GUEST)
286 .Lsie_entry:
287 sie 0(%r14)
288 .Lsie_exit:
289 BPOFF
290 BPENTER __SF_SIE_FLAGS(%r15),(_TIF_ISOLATE_BP|_TIF_ISOLATE_BP_GUEST)
291 .Lsie_skip:
292 ni __SIE_PROG0C+3(%r14),0xfe # no longer in SIE
293 lctlg %c1,%c1,__LC_USER_ASCE # load primary asce
294 .Lsie_done:
295 # some program checks are suppressing. C code (e.g. do_protection_exception)
296 # will rewind the PSW by the ILC, which is often 4 bytes in case of SIE. There
297 # are some corner cases (e.g. runtime instrumentation) where ILC is unpredictable.
298 # Other instructions between sie64a and .Lsie_done should not cause program
299 # interrupts. So lets use 3 nops as a landing pad for all possible rewinds.
300 # See also .Lcleanup_sie
301 .Lrewind_pad6:
302 nopr 7
303 .Lrewind_pad4:
304 nopr 7
305 .Lrewind_pad2:
306 nopr 7
307 .globl sie_exit
308 sie_exit:
309 lg %r14,__SF_SIE_SAVEAREA(%r15) # load guest register save area
310 stmg %r0,%r13,0(%r14) # save guest gprs 0-13
311 xgr %r0,%r0 # clear guest registers to
312 xgr %r1,%r1 # prevent speculative use
313 xgr %r2,%r2
314 xgr %r3,%r3
315 xgr %r4,%r4
316 xgr %r5,%r5
317 lmg %r6,%r14,__SF_GPRS(%r15) # restore kernel registers
318 lg %r2,__SF_SIE_REASON(%r15) # return exit reason code
319 BR_EX %r14
320 .Lsie_fault:
321 lghi %r14,-EFAULT
322 stg %r14,__SF_SIE_REASON(%r15) # set exit reason code
323 j sie_exit
325 EX_TABLE(.Lrewind_pad6,.Lsie_fault)
326 EX_TABLE(.Lrewind_pad4,.Lsie_fault)
327 EX_TABLE(.Lrewind_pad2,.Lsie_fault)
328 EX_TABLE(sie_exit,.Lsie_fault)
329 ENDPROC(sie64a)
330 EXPORT_SYMBOL(sie64a)
331 EXPORT_SYMBOL(sie_exit)
332 #endif
334 /*
335 * SVC interrupt handler routine. System calls are synchronous events and
336 * are executed with interrupts enabled.
337 */
339 ENTRY(system_call)
340 stpt __LC_SYNC_ENTER_TIMER
341 .Lsysc_stmg:
342 stmg %r8,%r15,__LC_SAVE_AREA_SYNC
343 BPOFF
344 lg %r12,__LC_CURRENT
345 lghi %r13,__TASK_thread
346 lghi %r14,_PIF_SYSCALL
347 .Lsysc_per:
348 lg %r15,__LC_KERNEL_STACK
349 la %r11,STACK_FRAME_OVERHEAD(%r15) # pointer to pt_regs
350 .Lsysc_vtime:
351 UPDATE_VTIME %r8,%r9,__LC_SYNC_ENTER_TIMER
352 BPENTER __TI_flags(%r12),_TIF_ISOLATE_BP
353 stmg %r0,%r7,__PT_R0(%r11)
354 mvc __PT_R8(64,%r11),__LC_SAVE_AREA_SYNC
355 mvc __PT_PSW(16,%r11),__LC_SVC_OLD_PSW
356 mvc __PT_INT_CODE(4,%r11),__LC_SVC_ILC
357 stg %r14,__PT_FLAGS(%r11)
358 .Lsysc_do_svc:
359 # clear user controlled register to prevent speculative use
360 xgr %r0,%r0
361 # load address of system call table
362 lg %r10,__THREAD_sysc_table(%r13,%r12)
363 llgh %r8,__PT_INT_CODE+2(%r11)
364 slag %r8,%r8,3 # shift and test for svc 0
365 jnz .Lsysc_nr_ok
366 # svc 0: system call number in %r1
367 llgfr %r1,%r1 # clear high word in r1
368 cghi %r1,NR_syscalls
369 jnl .Lsysc_nr_ok
370 sth %r1,__PT_INT_CODE+2(%r11)
371 slag %r8,%r1,3
372 .Lsysc_nr_ok:
373 xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
374 stg %r2,__PT_ORIG_GPR2(%r11)
375 stg %r7,STACK_FRAME_OVERHEAD(%r15)
376 lg %r9,0(%r8,%r10) # get system call add.
377 TSTMSK __TI_flags(%r12),_TIF_TRACE
378 jnz .Lsysc_tracesys
379 BASR_EX %r14,%r9 # call sys_xxxx
380 stg %r2,__PT_R2(%r11) # store return value
382 .Lsysc_return:
383 #ifdef CONFIG_DEBUG_RSEQ
384 lgr %r2,%r11
385 brasl %r14,rseq_syscall
386 #endif
387 LOCKDEP_SYS_EXIT
388 .Lsysc_tif:
389 TSTMSK __PT_FLAGS(%r11),_PIF_WORK
390 jnz .Lsysc_work
391 TSTMSK __TI_flags(%r12),_TIF_WORK
392 jnz .Lsysc_work # check for work
393 TSTMSK __LC_CPU_FLAGS,_CIF_WORK
394 jnz .Lsysc_work
395 BPEXIT __TI_flags(%r12),_TIF_ISOLATE_BP
396 .Lsysc_restore:
397 lg %r14,__LC_VDSO_PER_CPU
398 lmg %r0,%r10,__PT_R0(%r11)
399 mvc __LC_RETURN_PSW(16),__PT_PSW(%r11)
400 .Lsysc_exit_timer:
401 stpt __LC_EXIT_TIMER
402 mvc __VDSO_ECTG_BASE(16,%r14),__LC_EXIT_TIMER
403 lmg %r11,%r15,__PT_R11(%r11)
404 lpswe __LC_RETURN_PSW
405 .Lsysc_done:
407 #
408 # One of the work bits is on. Find out which one.
409 #
410 .Lsysc_work:
411 TSTMSK __LC_CPU_FLAGS,_CIF_MCCK_PENDING
412 jo .Lsysc_mcck_pending
413 TSTMSK __TI_flags(%r12),_TIF_NEED_RESCHED
414 jo .Lsysc_reschedule
415 TSTMSK __PT_FLAGS(%r11),_PIF_SYSCALL_RESTART
416 jo .Lsysc_syscall_restart
417 #ifdef CONFIG_UPROBES
418 TSTMSK __TI_flags(%r12),_TIF_UPROBE
419 jo .Lsysc_uprobe_notify
420 #endif
421 TSTMSK __TI_flags(%r12),_TIF_GUARDED_STORAGE
422 jo .Lsysc_guarded_storage
423 TSTMSK __PT_FLAGS(%r11),_PIF_PER_TRAP
424 jo .Lsysc_singlestep
425 #ifdef CONFIG_LIVEPATCH
426 TSTMSK __TI_flags(%r12),_TIF_PATCH_PENDING
427 jo .Lsysc_patch_pending # handle live patching just before
428 # signals and possible syscall restart
429 #endif
430 TSTMSK __PT_FLAGS(%r11),_PIF_SYSCALL_RESTART
431 jo .Lsysc_syscall_restart
432 TSTMSK __TI_flags(%r12),_TIF_SIGPENDING
433 jo .Lsysc_sigpending
434 TSTMSK __TI_flags(%r12),_TIF_NOTIFY_RESUME
435 jo .Lsysc_notify_resume
436 TSTMSK __LC_CPU_FLAGS,_CIF_FPU
437 jo .Lsysc_vxrs
438 TSTMSK __LC_CPU_FLAGS,(_CIF_ASCE_PRIMARY|_CIF_ASCE_SECONDARY)
439 jnz .Lsysc_asce
440 j .Lsysc_return # beware of critical section cleanup
442 #
443 # _TIF_NEED_RESCHED is set, call schedule
444 #
445 .Lsysc_reschedule:
446 larl %r14,.Lsysc_return
447 jg schedule
449 #
450 # _CIF_MCCK_PENDING is set, call handler
451 #
452 .Lsysc_mcck_pending:
453 larl %r14,.Lsysc_return
454 jg s390_handle_mcck # TIF bit will be cleared by handler
456 #
457 # _CIF_ASCE_PRIMARY and/or _CIF_ASCE_SECONDARY set, load user space asce
458 #
459 .Lsysc_asce:
460 ni __LC_CPU_FLAGS+7,255-_CIF_ASCE_SECONDARY
461 lctlg %c7,%c7,__LC_VDSO_ASCE # load secondary asce
462 TSTMSK __LC_CPU_FLAGS,_CIF_ASCE_PRIMARY
463 jz .Lsysc_return
464 #ifndef CONFIG_HAVE_MARCH_Z10_FEATURES
465 tm __LC_STFLE_FAC_LIST+3,0x10 # has MVCOS ?
466 jnz .Lsysc_set_fs_fixup
467 ni __LC_CPU_FLAGS+7,255-_CIF_ASCE_PRIMARY
468 lctlg %c1,%c1,__LC_USER_ASCE # load primary asce
469 j .Lsysc_return
470 .Lsysc_set_fs_fixup:
471 #endif
472 larl %r14,.Lsysc_return
473 jg set_fs_fixup
475 #
476 # CIF_FPU is set, restore floating-point controls and floating-point registers.
477 #
478 .Lsysc_vxrs:
479 larl %r14,.Lsysc_return
480 jg load_fpu_regs
482 #
483 # _TIF_SIGPENDING is set, call do_signal
484 #
485 .Lsysc_sigpending:
486 lgr %r2,%r11 # pass pointer to pt_regs
487 brasl %r14,do_signal
488 TSTMSK __PT_FLAGS(%r11),_PIF_SYSCALL
489 jno .Lsysc_return
490 .Lsysc_do_syscall:
491 lghi %r13,__TASK_thread
492 lmg %r2,%r7,__PT_R2(%r11) # load svc arguments
493 lghi %r1,0 # svc 0 returns -ENOSYS
494 j .Lsysc_do_svc
496 #
497 # _TIF_NOTIFY_RESUME is set, call do_notify_resume
498 #
499 .Lsysc_notify_resume:
500 lgr %r2,%r11 # pass pointer to pt_regs
501 larl %r14,.Lsysc_return
502 jg do_notify_resume
504 #
505 # _TIF_UPROBE is set, call uprobe_notify_resume
506 #
507 #ifdef CONFIG_UPROBES
508 .Lsysc_uprobe_notify:
509 lgr %r2,%r11 # pass pointer to pt_regs
510 larl %r14,.Lsysc_return
511 jg uprobe_notify_resume
512 #endif
514 #
515 # _TIF_GUARDED_STORAGE is set, call guarded_storage_load
516 #
517 .Lsysc_guarded_storage:
518 lgr %r2,%r11 # pass pointer to pt_regs
519 larl %r14,.Lsysc_return
520 jg gs_load_bc_cb
521 #
522 # _TIF_PATCH_PENDING is set, call klp_update_patch_state
523 #
524 #ifdef CONFIG_LIVEPATCH
525 .Lsysc_patch_pending:
526 lg %r2,__LC_CURRENT # pass pointer to task struct
527 larl %r14,.Lsysc_return
528 jg klp_update_patch_state
529 #endif
531 #
532 # _PIF_PER_TRAP is set, call do_per_trap
533 #
534 .Lsysc_singlestep:
535 ni __PT_FLAGS+7(%r11),255-_PIF_PER_TRAP
536 lgr %r2,%r11 # pass pointer to pt_regs
537 larl %r14,.Lsysc_return
538 jg do_per_trap
540 #
541 # _PIF_SYSCALL_RESTART is set, repeat the current system call
542 #
543 .Lsysc_syscall_restart:
544 ni __PT_FLAGS+7(%r11),255-_PIF_SYSCALL_RESTART
545 lmg %r1,%r7,__PT_R1(%r11) # load svc arguments
546 lg %r2,__PT_ORIG_GPR2(%r11)
547 j .Lsysc_do_svc
549 #
550 # call tracehook_report_syscall_entry/tracehook_report_syscall_exit before
551 # and after the system call
552 #
553 .Lsysc_tracesys:
554 lgr %r2,%r11 # pass pointer to pt_regs
555 la %r3,0
556 llgh %r0,__PT_INT_CODE+2(%r11)
557 stg %r0,__PT_R2(%r11)
558 brasl %r14,do_syscall_trace_enter
559 lghi %r0,NR_syscalls
560 clgr %r0,%r2
561 jnh .Lsysc_tracenogo
562 sllg %r8,%r2,3
563 lg %r9,0(%r8,%r10)
564 .Lsysc_tracego:
565 lmg %r3,%r7,__PT_R3(%r11)
566 stg %r7,STACK_FRAME_OVERHEAD(%r15)
567 lg %r2,__PT_ORIG_GPR2(%r11)
568 BASR_EX %r14,%r9 # call sys_xxx
569 stg %r2,__PT_R2(%r11) # store return value
570 .Lsysc_tracenogo:
571 TSTMSK __TI_flags(%r12),_TIF_TRACE
572 jz .Lsysc_return
573 lgr %r2,%r11 # pass pointer to pt_regs
574 larl %r14,.Lsysc_return
575 jg do_syscall_trace_exit
576 ENDPROC(system_call)
578 #
579 # a new process exits the kernel with ret_from_fork
580 #
581 ENTRY(ret_from_fork)
582 la %r11,STACK_FRAME_OVERHEAD(%r15)
583 lg %r12,__LC_CURRENT
584 brasl %r14,schedule_tail
585 TRACE_IRQS_ON
586 ssm __LC_SVC_NEW_PSW # reenable interrupts
587 tm __PT_PSW+1(%r11),0x01 # forking a kernel thread ?
588 jne .Lsysc_tracenogo
589 # it's a kernel thread
590 lmg %r9,%r10,__PT_R9(%r11) # load gprs
591 la %r2,0(%r10)
592 BASR_EX %r14,%r9
593 j .Lsysc_tracenogo
594 ENDPROC(ret_from_fork)
596 ENTRY(kernel_thread_starter)
597 la %r2,0(%r10)
598 BASR_EX %r14,%r9
599 j .Lsysc_tracenogo
600 ENDPROC(kernel_thread_starter)
602 /*
603 * Program check handler routine
604 */
606 ENTRY(pgm_check_handler)
607 stpt __LC_SYNC_ENTER_TIMER
608 BPOFF
609 stmg %r8,%r15,__LC_SAVE_AREA_SYNC
610 lg %r10,__LC_LAST_BREAK
611 lg %r12,__LC_CURRENT
612 lghi %r11,0
613 larl %r13,cleanup_critical
614 lmg %r8,%r9,__LC_PGM_OLD_PSW
615 tmhh %r8,0x0001 # test problem state bit
616 jnz 2f # -> fault in user space
617 #if IS_ENABLED(CONFIG_KVM)
618 # cleanup critical section for program checks in sie64a
619 lgr %r14,%r9
620 slg %r14,BASED(.Lsie_critical_start)
621 clg %r14,BASED(.Lsie_critical_length)
622 jhe 0f
623 lg %r14,__SF_SIE_CONTROL(%r15) # get control block pointer
624 ni __SIE_PROG0C+3(%r14),0xfe # no longer in SIE
625 lctlg %c1,%c1,__LC_USER_ASCE # load primary asce
626 larl %r9,sie_exit # skip forward to sie_exit
627 lghi %r11,_PIF_GUEST_FAULT
628 #endif
629 0: tmhh %r8,0x4000 # PER bit set in old PSW ?
630 jnz 1f # -> enabled, can't be a double fault
631 tm __LC_PGM_ILC+3,0x80 # check for per exception
632 jnz .Lpgm_svcper # -> single stepped svc
633 1: CHECK_STACK __LC_SAVE_AREA_SYNC
634 aghi %r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE)
635 # CHECK_VMAP_STACK branches to stack_overflow or 4f
636 CHECK_VMAP_STACK __LC_SAVE_AREA_SYNC,4f
637 2: UPDATE_VTIME %r14,%r15,__LC_SYNC_ENTER_TIMER
638 BPENTER __TI_flags(%r12),_TIF_ISOLATE_BP
639 lg %r15,__LC_KERNEL_STACK
640 lgr %r14,%r12
641 aghi %r14,__TASK_thread # pointer to thread_struct
642 lghi %r13,__LC_PGM_TDB
643 tm __LC_PGM_ILC+2,0x02 # check for transaction abort
644 jz 3f
645 mvc __THREAD_trap_tdb(256,%r14),0(%r13)
646 3: stg %r10,__THREAD_last_break(%r14)
647 4: lgr %r13,%r11
648 la %r11,STACK_FRAME_OVERHEAD(%r15)
649 stmg %r0,%r7,__PT_R0(%r11)
650 # clear user controlled registers to prevent speculative use
651 xgr %r0,%r0
652 xgr %r1,%r1
653 xgr %r2,%r2
654 xgr %r3,%r3
655 xgr %r4,%r4
656 xgr %r5,%r5
657 xgr %r6,%r6
658 xgr %r7,%r7
659 mvc __PT_R8(64,%r11),__LC_SAVE_AREA_SYNC
660 stmg %r8,%r9,__PT_PSW(%r11)
661 mvc __PT_INT_CODE(4,%r11),__LC_PGM_ILC
662 mvc __PT_INT_PARM_LONG(8,%r11),__LC_TRANS_EXC_CODE
663 stg %r13,__PT_FLAGS(%r11)
664 stg %r10,__PT_ARGS(%r11)
665 tm __LC_PGM_ILC+3,0x80 # check for per exception
666 jz 5f
667 tmhh %r8,0x0001 # kernel per event ?
668 jz .Lpgm_kprobe
669 oi __PT_FLAGS+7(%r11),_PIF_PER_TRAP
670 mvc __THREAD_per_address(8,%r14),__LC_PER_ADDRESS
671 mvc __THREAD_per_cause(2,%r14),__LC_PER_CODE
672 mvc __THREAD_per_paid(1,%r14),__LC_PER_ACCESS_ID
673 5: REENABLE_IRQS
674 xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
675 larl %r1,pgm_check_table
676 llgh %r10,__PT_INT_CODE+2(%r11)
677 nill %r10,0x007f
678 sll %r10,3
679 je .Lpgm_return
680 lg %r9,0(%r10,%r1) # load address of handler routine
681 lgr %r2,%r11 # pass pointer to pt_regs
682 BASR_EX %r14,%r9 # branch to interrupt-handler
683 .Lpgm_return:
684 LOCKDEP_SYS_EXIT
685 tm __PT_PSW+1(%r11),0x01 # returning to user ?
686 jno .Lsysc_restore
687 TSTMSK __PT_FLAGS(%r11),_PIF_SYSCALL
688 jo .Lsysc_do_syscall
689 j .Lsysc_tif
691 #
692 # PER event in supervisor state, must be kprobes
693 #
694 .Lpgm_kprobe:
695 REENABLE_IRQS
696 xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
697 lgr %r2,%r11 # pass pointer to pt_regs
698 brasl %r14,do_per_trap
699 j .Lpgm_return
701 #
702 # single stepped system call
703 #
704 .Lpgm_svcper:
705 mvc __LC_RETURN_PSW(8),__LC_SVC_NEW_PSW
706 lghi %r13,__TASK_thread
707 larl %r14,.Lsysc_per
708 stg %r14,__LC_RETURN_PSW+8
709 lghi %r14,_PIF_SYSCALL | _PIF_PER_TRAP
710 lpswe __LC_RETURN_PSW # branch to .Lsysc_per and enable irqs
711 ENDPROC(pgm_check_handler)
713 /*
714 * IO interrupt handler routine
715 */
716 ENTRY(io_int_handler)
717 STCK __LC_INT_CLOCK
718 stpt __LC_ASYNC_ENTER_TIMER
719 BPOFF
720 stmg %r8,%r15,__LC_SAVE_AREA_ASYNC
721 lg %r12,__LC_CURRENT
722 larl %r13,cleanup_critical
723 lmg %r8,%r9,__LC_IO_OLD_PSW
724 SWITCH_ASYNC __LC_SAVE_AREA_ASYNC,__LC_ASYNC_ENTER_TIMER
725 stmg %r0,%r7,__PT_R0(%r11)
726 # clear user controlled registers to prevent speculative use
727 xgr %r0,%r0
728 xgr %r1,%r1
729 xgr %r2,%r2
730 xgr %r3,%r3
731 xgr %r4,%r4
732 xgr %r5,%r5
733 xgr %r6,%r6
734 xgr %r7,%r7
735 xgr %r10,%r10
736 mvc __PT_R8(64,%r11),__LC_SAVE_AREA_ASYNC
737 stmg %r8,%r9,__PT_PSW(%r11)
738 mvc __PT_INT_CODE(12,%r11),__LC_SUBCHANNEL_ID
739 xc __PT_FLAGS(8,%r11),__PT_FLAGS(%r11)
740 TSTMSK __LC_CPU_FLAGS,_CIF_IGNORE_IRQ
741 jo .Lio_restore
742 TRACE_IRQS_OFF
743 xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
744 .Lio_loop:
745 lgr %r2,%r11 # pass pointer to pt_regs
746 lghi %r3,IO_INTERRUPT
747 tm __PT_INT_CODE+8(%r11),0x80 # adapter interrupt ?
748 jz .Lio_call
749 lghi %r3,THIN_INTERRUPT
750 .Lio_call:
751 brasl %r14,do_IRQ
752 TSTMSK __LC_MACHINE_FLAGS,MACHINE_FLAG_LPAR
753 jz .Lio_return
754 tpi 0
755 jz .Lio_return
756 mvc __PT_INT_CODE(12,%r11),__LC_SUBCHANNEL_ID
757 j .Lio_loop
758 .Lio_return:
759 LOCKDEP_SYS_EXIT
760 TRACE_IRQS_ON
761 .Lio_tif:
762 TSTMSK __TI_flags(%r12),_TIF_WORK
763 jnz .Lio_work # there is work to do (signals etc.)
764 TSTMSK __LC_CPU_FLAGS,_CIF_WORK
765 jnz .Lio_work
766 .Lio_restore:
767 lg %r14,__LC_VDSO_PER_CPU
768 lmg %r0,%r10,__PT_R0(%r11)
769 mvc __LC_RETURN_PSW(16),__PT_PSW(%r11)
770 tm __PT_PSW+1(%r11),0x01 # returning to user ?
771 jno .Lio_exit_kernel
772 BPEXIT __TI_flags(%r12),_TIF_ISOLATE_BP
773 .Lio_exit_timer:
774 stpt __LC_EXIT_TIMER
775 mvc __VDSO_ECTG_BASE(16,%r14),__LC_EXIT_TIMER
776 .Lio_exit_kernel:
777 lmg %r11,%r15,__PT_R11(%r11)
778 lpswe __LC_RETURN_PSW
779 .Lio_done:
781 #
782 # There is work todo, find out in which context we have been interrupted:
783 # 1) if we return to user space we can do all _TIF_WORK work
784 # 2) if we return to kernel code and kvm is enabled check if we need to
785 # modify the psw to leave SIE
786 # 3) if we return to kernel code and preemptive scheduling is enabled check
787 # the preemption counter and if it is zero call preempt_schedule_irq
788 # Before any work can be done, a switch to the kernel stack is required.
789 #
790 .Lio_work:
791 tm __PT_PSW+1(%r11),0x01 # returning to user ?
792 jo .Lio_work_user # yes -> do resched & signal
793 #ifdef CONFIG_PREEMPT
794 # check for preemptive scheduling
795 icm %r0,15,__LC_PREEMPT_COUNT
796 jnz .Lio_restore # preemption is disabled
797 TSTMSK __TI_flags(%r12),_TIF_NEED_RESCHED
798 jno .Lio_restore
799 # switch to kernel stack
800 lg %r1,__PT_R15(%r11)
801 aghi %r1,-(STACK_FRAME_OVERHEAD + __PT_SIZE)
802 mvc STACK_FRAME_OVERHEAD(__PT_SIZE,%r1),0(%r11)
803 xc __SF_BACKCHAIN(8,%r1),__SF_BACKCHAIN(%r1)
804 la %r11,STACK_FRAME_OVERHEAD(%r1)
805 lgr %r15,%r1
806 # TRACE_IRQS_ON already done at .Lio_return, call
807 # TRACE_IRQS_OFF to keep things symmetrical
808 TRACE_IRQS_OFF
809 brasl %r14,preempt_schedule_irq
810 j .Lio_return
811 #else
812 j .Lio_restore
813 #endif
815 #
816 # Need to do work before returning to userspace, switch to kernel stack
817 #
818 .Lio_work_user:
819 lg %r1,__LC_KERNEL_STACK
820 mvc STACK_FRAME_OVERHEAD(__PT_SIZE,%r1),0(%r11)
821 xc __SF_BACKCHAIN(8,%r1),__SF_BACKCHAIN(%r1)
822 la %r11,STACK_FRAME_OVERHEAD(%r1)
823 lgr %r15,%r1
825 #
826 # One of the work bits is on. Find out which one.
827 #
828 .Lio_work_tif:
829 TSTMSK __LC_CPU_FLAGS,_CIF_MCCK_PENDING
830 jo .Lio_mcck_pending
831 TSTMSK __TI_flags(%r12),_TIF_NEED_RESCHED
832 jo .Lio_reschedule
833 #ifdef CONFIG_LIVEPATCH
834 TSTMSK __TI_flags(%r12),_TIF_PATCH_PENDING
835 jo .Lio_patch_pending
836 #endif
837 TSTMSK __TI_flags(%r12),_TIF_SIGPENDING
838 jo .Lio_sigpending
839 TSTMSK __TI_flags(%r12),_TIF_NOTIFY_RESUME
840 jo .Lio_notify_resume
841 TSTMSK __TI_flags(%r12),_TIF_GUARDED_STORAGE
842 jo .Lio_guarded_storage
843 TSTMSK __LC_CPU_FLAGS,_CIF_FPU
844 jo .Lio_vxrs
845 TSTMSK __LC_CPU_FLAGS,(_CIF_ASCE_PRIMARY|_CIF_ASCE_SECONDARY)
846 jnz .Lio_asce
847 j .Lio_return # beware of critical section cleanup
849 #
850 # _CIF_MCCK_PENDING is set, call handler
851 #
852 .Lio_mcck_pending:
853 # TRACE_IRQS_ON already done at .Lio_return
854 brasl %r14,s390_handle_mcck # TIF bit will be cleared by handler
855 TRACE_IRQS_OFF
856 j .Lio_return
858 #
859 # _CIF_ASCE_PRIMARY and/or CIF_ASCE_SECONDARY set, load user space asce
860 #
861 .Lio_asce:
862 ni __LC_CPU_FLAGS+7,255-_CIF_ASCE_SECONDARY
863 lctlg %c7,%c7,__LC_VDSO_ASCE # load secondary asce
864 TSTMSK __LC_CPU_FLAGS,_CIF_ASCE_PRIMARY
865 jz .Lio_return
866 #ifndef CONFIG_HAVE_MARCH_Z10_FEATURES
867 tm __LC_STFLE_FAC_LIST+3,0x10 # has MVCOS ?
868 jnz .Lio_set_fs_fixup
869 ni __LC_CPU_FLAGS+7,255-_CIF_ASCE_PRIMARY
870 lctlg %c1,%c1,__LC_USER_ASCE # load primary asce
871 j .Lio_return
872 .Lio_set_fs_fixup:
873 #endif
874 larl %r14,.Lio_return
875 jg set_fs_fixup
877 #
878 # CIF_FPU is set, restore floating-point controls and floating-point registers.
879 #
880 .Lio_vxrs:
881 larl %r14,.Lio_return
882 jg load_fpu_regs
884 #
885 # _TIF_GUARDED_STORAGE is set, call guarded_storage_load
886 #
887 .Lio_guarded_storage:
888 # TRACE_IRQS_ON already done at .Lio_return
889 ssm __LC_SVC_NEW_PSW # reenable interrupts
890 lgr %r2,%r11 # pass pointer to pt_regs
891 brasl %r14,gs_load_bc_cb
892 ssm __LC_PGM_NEW_PSW # disable I/O and ext. interrupts
893 TRACE_IRQS_OFF
894 j .Lio_return
896 #
897 # _TIF_NEED_RESCHED is set, call schedule
898 #
899 .Lio_reschedule:
900 # TRACE_IRQS_ON already done at .Lio_return
901 ssm __LC_SVC_NEW_PSW # reenable interrupts
902 brasl %r14,schedule # call scheduler
903 ssm __LC_PGM_NEW_PSW # disable I/O and ext. interrupts
904 TRACE_IRQS_OFF
905 j .Lio_return
907 #
908 # _TIF_PATCH_PENDING is set, call klp_update_patch_state
909 #
910 #ifdef CONFIG_LIVEPATCH
911 .Lio_patch_pending:
912 lg %r2,__LC_CURRENT # pass pointer to task struct
913 larl %r14,.Lio_return
914 jg klp_update_patch_state
915 #endif
917 #
918 # _TIF_SIGPENDING or is set, call do_signal
919 #
920 .Lio_sigpending:
921 # TRACE_IRQS_ON already done at .Lio_return
922 ssm __LC_SVC_NEW_PSW # reenable interrupts
923 lgr %r2,%r11 # pass pointer to pt_regs
924 brasl %r14,do_signal
925 ssm __LC_PGM_NEW_PSW # disable I/O and ext. interrupts
926 TRACE_IRQS_OFF
927 j .Lio_return
929 #
930 # _TIF_NOTIFY_RESUME or is set, call do_notify_resume
931 #
932 .Lio_notify_resume:
933 # TRACE_IRQS_ON already done at .Lio_return
934 ssm __LC_SVC_NEW_PSW # reenable interrupts
935 lgr %r2,%r11 # pass pointer to pt_regs
936 brasl %r14,do_notify_resume
937 ssm __LC_PGM_NEW_PSW # disable I/O and ext. interrupts
938 TRACE_IRQS_OFF
939 j .Lio_return
940 ENDPROC(io_int_handler)
942 /*
943 * External interrupt handler routine
944 */
945 ENTRY(ext_int_handler)
946 STCK __LC_INT_CLOCK
947 stpt __LC_ASYNC_ENTER_TIMER
948 BPOFF
949 stmg %r8,%r15,__LC_SAVE_AREA_ASYNC
950 lg %r12,__LC_CURRENT
951 larl %r13,cleanup_critical
952 lmg %r8,%r9,__LC_EXT_OLD_PSW
953 SWITCH_ASYNC __LC_SAVE_AREA_ASYNC,__LC_ASYNC_ENTER_TIMER
954 stmg %r0,%r7,__PT_R0(%r11)
955 # clear user controlled registers to prevent speculative use
956 xgr %r0,%r0
957 xgr %r1,%r1
958 xgr %r2,%r2
959 xgr %r3,%r3
960 xgr %r4,%r4
961 xgr %r5,%r5
962 xgr %r6,%r6
963 xgr %r7,%r7
964 xgr %r10,%r10
965 mvc __PT_R8(64,%r11),__LC_SAVE_AREA_ASYNC
966 stmg %r8,%r9,__PT_PSW(%r11)
967 lghi %r1,__LC_EXT_PARAMS2
968 mvc __PT_INT_CODE(4,%r11),__LC_EXT_CPU_ADDR
969 mvc __PT_INT_PARM(4,%r11),__LC_EXT_PARAMS
970 mvc __PT_INT_PARM_LONG(8,%r11),0(%r1)
971 xc __PT_FLAGS(8,%r11),__PT_FLAGS(%r11)
972 TSTMSK __LC_CPU_FLAGS,_CIF_IGNORE_IRQ
973 jo .Lio_restore
974 TRACE_IRQS_OFF
975 xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
976 lgr %r2,%r11 # pass pointer to pt_regs
977 lghi %r3,EXT_INTERRUPT
978 brasl %r14,do_IRQ
979 j .Lio_return
980 ENDPROC(ext_int_handler)
982 /*
983 * Load idle PSW. The second "half" of this function is in .Lcleanup_idle.
984 */
985 ENTRY(psw_idle)
986 stg %r3,__SF_EMPTY(%r15)
987 larl %r1,.Lpsw_idle_lpsw+4
988 stg %r1,__SF_EMPTY+8(%r15)
989 #ifdef CONFIG_SMP
990 larl %r1,smp_cpu_mtid
991 llgf %r1,0(%r1)
992 ltgr %r1,%r1
993 jz .Lpsw_idle_stcctm
994 .insn rsy,0xeb0000000017,%r1,5,__SF_EMPTY+16(%r15)
995 .Lpsw_idle_stcctm:
996 #endif
997 oi __LC_CPU_FLAGS+7,_CIF_ENABLED_WAIT
998 BPON
999 STCK __CLOCK_IDLE_ENTER(%r2)
1000 stpt __TIMER_IDLE_ENTER(%r2)
1001 .Lpsw_idle_lpsw:
1002 lpswe __SF_EMPTY(%r15)
1003 BR_EX %r14
1004 .Lpsw_idle_end:
1005 ENDPROC(psw_idle)
1007 /*
1008 * Store floating-point controls and floating-point or vector register
1009 * depending whether the vector facility is available. A critical section
1010 * cleanup assures that the registers are stored even if interrupted for
1011 * some other work. The CIF_FPU flag is set to trigger a lazy restore
1012 * of the register contents at return from io or a system call.
1013 */
1014 ENTRY(save_fpu_regs)
1015 lg %r2,__LC_CURRENT
1016 aghi %r2,__TASK_thread
1017 TSTMSK __LC_CPU_FLAGS,_CIF_FPU
1018 jo .Lsave_fpu_regs_exit
1019 stfpc __THREAD_FPU_fpc(%r2)
1020 lg %r3,__THREAD_FPU_regs(%r2)
1021 TSTMSK __LC_MACHINE_FLAGS,MACHINE_FLAG_VX
1022 jz .Lsave_fpu_regs_fp # no -> store FP regs
1023 VSTM %v0,%v15,0,%r3 # vstm 0,15,0(3)
1024 VSTM %v16,%v31,256,%r3 # vstm 16,31,256(3)
1025 j .Lsave_fpu_regs_done # -> set CIF_FPU flag
1026 .Lsave_fpu_regs_fp:
1027 std 0,0(%r3)
1028 std 1,8(%r3)
1029 std 2,16(%r3)
1030 std 3,24(%r3)
1031 std 4,32(%r3)
1032 std 5,40(%r3)
1033 std 6,48(%r3)
1034 std 7,56(%r3)
1035 std 8,64(%r3)
1036 std 9,72(%r3)
1037 std 10,80(%r3)
1038 std 11,88(%r3)
1039 std 12,96(%r3)
1040 std 13,104(%r3)
1041 std 14,112(%r3)
1042 std 15,120(%r3)
1043 .Lsave_fpu_regs_done:
1044 oi __LC_CPU_FLAGS+7,_CIF_FPU
1045 .Lsave_fpu_regs_exit:
1046 BR_EX %r14
1047 .Lsave_fpu_regs_end:
1048 ENDPROC(save_fpu_regs)
1049 EXPORT_SYMBOL(save_fpu_regs)
1051 /*
1052 * Load floating-point controls and floating-point or vector registers.
1053 * A critical section cleanup assures that the register contents are
1054 * loaded even if interrupted for some other work.
1055 *
1056 * There are special calling conventions to fit into sysc and io return work:
1057 * %r15: <kernel stack>
1058 * The function requires:
1059 * %r4
1060 */
1061 load_fpu_regs:
1062 lg %r4,__LC_CURRENT
1063 aghi %r4,__TASK_thread
1064 TSTMSK __LC_CPU_FLAGS,_CIF_FPU
1065 jno .Lload_fpu_regs_exit
1066 lfpc __THREAD_FPU_fpc(%r4)
1067 TSTMSK __LC_MACHINE_FLAGS,MACHINE_FLAG_VX
1068 lg %r4,__THREAD_FPU_regs(%r4) # %r4 <- reg save area
1069 jz .Lload_fpu_regs_fp # -> no VX, load FP regs
1070 VLM %v0,%v15,0,%r4
1071 VLM %v16,%v31,256,%r4
1072 j .Lload_fpu_regs_done
1073 .Lload_fpu_regs_fp:
1074 ld 0,0(%r4)
1075 ld 1,8(%r4)
1076 ld 2,16(%r4)
1077 ld 3,24(%r4)
1078 ld 4,32(%r4)
1079 ld 5,40(%r4)
1080 ld 6,48(%r4)
1081 ld 7,56(%r4)
1082 ld 8,64(%r4)
1083 ld 9,72(%r4)
1084 ld 10,80(%r4)
1085 ld 11,88(%r4)
1086 ld 12,96(%r4)
1087 ld 13,104(%r4)
1088 ld 14,112(%r4)
1089 ld 15,120(%r4)
1090 .Lload_fpu_regs_done:
1091 ni __LC_CPU_FLAGS+7,255-_CIF_FPU
1092 .Lload_fpu_regs_exit:
1093 BR_EX %r14
1094 .Lload_fpu_regs_end:
1095 ENDPROC(load_fpu_regs)
1097 .L__critical_end:
1099 /*
1100 * Machine check handler routines
1101 */
1102 ENTRY(mcck_int_handler)
1103 STCK __LC_MCCK_CLOCK
1104 BPOFF
1105 la %r1,4095 # validate r1
1106 spt __LC_CPU_TIMER_SAVE_AREA-4095(%r1) # validate cpu timer
1107 sckc __LC_CLOCK_COMPARATOR # validate comparator
1108 lam %a0,%a15,__LC_AREGS_SAVE_AREA-4095(%r1) # validate acrs
1109 lmg %r0,%r15,__LC_GPREGS_SAVE_AREA-4095(%r1)# validate gprs
1110 lg %r12,__LC_CURRENT
1111 larl %r13,cleanup_critical
1112 lmg %r8,%r9,__LC_MCK_OLD_PSW
1113 TSTMSK __LC_MCCK_CODE,MCCK_CODE_SYSTEM_DAMAGE
1114 jo .Lmcck_panic # yes -> rest of mcck code invalid
1115 TSTMSK __LC_MCCK_CODE,MCCK_CODE_CR_VALID
1116 jno .Lmcck_panic # control registers invalid -> panic
1117 la %r14,4095
1118 lctlg %c0,%c15,__LC_CREGS_SAVE_AREA-4095(%r14) # validate ctl regs
1119 ptlb
1120 lg %r11,__LC_MCESAD-4095(%r14) # extended machine check save area
1121 nill %r11,0xfc00 # MCESA_ORIGIN_MASK
1122 TSTMSK __LC_CREGS_SAVE_AREA+16-4095(%r14),CR2_GUARDED_STORAGE
1123 jno 0f
1124 TSTMSK __LC_MCCK_CODE,MCCK_CODE_GS_VALID
1125 jno 0f
1126 .insn rxy,0xe3000000004d,0,__MCESA_GS_SAVE_AREA(%r11) # LGSC
1127 0: l %r14,__LC_FP_CREG_SAVE_AREA-4095(%r14)
1128 TSTMSK __LC_MCCK_CODE,MCCK_CODE_FC_VALID
1129 jo 0f
1130 sr %r14,%r14
1131 0: sfpc %r14
1132 TSTMSK __LC_MACHINE_FLAGS,MACHINE_FLAG_VX
1133 jo 0f
1134 lghi %r14,__LC_FPREGS_SAVE_AREA
1135 ld %f0,0(%r14)
1136 ld %f1,8(%r14)
1137 ld %f2,16(%r14)
1138 ld %f3,24(%r14)
1139 ld %f4,32(%r14)
1140 ld %f5,40(%r14)
1141 ld %f6,48(%r14)
1142 ld %f7,56(%r14)
1143 ld %f8,64(%r14)
1144 ld %f9,72(%r14)
1145 ld %f10,80(%r14)
1146 ld %f11,88(%r14)
1147 ld %f12,96(%r14)
1148 ld %f13,104(%r14)
1149 ld %f14,112(%r14)
1150 ld %f15,120(%r14)
1151 j 1f
1152 0: VLM %v0,%v15,0,%r11
1153 VLM %v16,%v31,256,%r11
1154 1: lghi %r14,__LC_CPU_TIMER_SAVE_AREA
1155 mvc __LC_MCCK_ENTER_TIMER(8),0(%r14)
1156 TSTMSK __LC_MCCK_CODE,MCCK_CODE_CPU_TIMER_VALID
1157 jo 3f
1158 la %r14,__LC_SYNC_ENTER_TIMER
1159 clc 0(8,%r14),__LC_ASYNC_ENTER_TIMER
1160 jl 0f
1161 la %r14,__LC_ASYNC_ENTER_TIMER
1162 0: clc 0(8,%r14),__LC_EXIT_TIMER
1163 jl 1f
1164 la %r14,__LC_EXIT_TIMER
1165 1: clc 0(8,%r14),__LC_LAST_UPDATE_TIMER
1166 jl 2f
1167 la %r14,__LC_LAST_UPDATE_TIMER
1168 2: spt 0(%r14)
1169 mvc __LC_MCCK_ENTER_TIMER(8),0(%r14)
1170 3: TSTMSK __LC_MCCK_CODE,MCCK_CODE_PSW_MWP_VALID
1171 jno .Lmcck_panic
1172 tmhh %r8,0x0001 # interrupting from user ?
1173 jnz 4f
1174 TSTMSK __LC_MCCK_CODE,MCCK_CODE_PSW_IA_VALID
1175 jno .Lmcck_panic
1176 4: ssm __LC_PGM_NEW_PSW # turn dat on, keep irqs off
1177 SWITCH_ASYNC __LC_GPREGS_SAVE_AREA+64,__LC_MCCK_ENTER_TIMER
1178 .Lmcck_skip:
1179 lghi %r14,__LC_GPREGS_SAVE_AREA+64
1180 stmg %r0,%r7,__PT_R0(%r11)
1181 # clear user controlled registers to prevent speculative use
1182 xgr %r0,%r0
1183 xgr %r1,%r1
1184 xgr %r2,%r2
1185 xgr %r3,%r3
1186 xgr %r4,%r4
1187 xgr %r5,%r5
1188 xgr %r6,%r6
1189 xgr %r7,%r7
1190 xgr %r10,%r10
1191 mvc __PT_R8(64,%r11),0(%r14)
1192 stmg %r8,%r9,__PT_PSW(%r11)
1193 xc __PT_FLAGS(8,%r11),__PT_FLAGS(%r11)
1194 xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
1195 lgr %r2,%r11 # pass pointer to pt_regs
1196 brasl %r14,s390_do_machine_check
1197 tm __PT_PSW+1(%r11),0x01 # returning to user ?
1198 jno .Lmcck_return
1199 lg %r1,__LC_KERNEL_STACK # switch to kernel stack
1200 mvc STACK_FRAME_OVERHEAD(__PT_SIZE,%r1),0(%r11)
1201 xc __SF_BACKCHAIN(8,%r1),__SF_BACKCHAIN(%r1)
1202 la %r11,STACK_FRAME_OVERHEAD(%r1)
1203 lgr %r15,%r1
1204 TSTMSK __LC_CPU_FLAGS,_CIF_MCCK_PENDING
1205 jno .Lmcck_return
1206 TRACE_IRQS_OFF
1207 brasl %r14,s390_handle_mcck
1208 TRACE_IRQS_ON
1209 .Lmcck_return:
1210 lg %r14,__LC_VDSO_PER_CPU
1211 lmg %r0,%r10,__PT_R0(%r11)
1212 mvc __LC_RETURN_MCCK_PSW(16),__PT_PSW(%r11) # move return PSW
1213 tm __LC_RETURN_MCCK_PSW+1,0x01 # returning to user ?
1214 jno 0f
1215 BPEXIT __TI_flags(%r12),_TIF_ISOLATE_BP
1216 stpt __LC_EXIT_TIMER
1217 mvc __VDSO_ECTG_BASE(16,%r14),__LC_EXIT_TIMER
1218 0: lmg %r11,%r15,__PT_R11(%r11)
1219 lpswe __LC_RETURN_MCCK_PSW
1221 .Lmcck_panic:
1222 lg %r15,__LC_NODAT_STACK
1223 la %r11,STACK_FRAME_OVERHEAD(%r15)
1224 j .Lmcck_skip
1225 ENDPROC(mcck_int_handler)
1227 #
1228 # PSW restart interrupt handler
1229 #
1230 ENTRY(restart_int_handler)
1231 ALTERNATIVE "", ".insn s,0xb2800000,_LPP_OFFSET", 40
1232 stg %r15,__LC_SAVE_AREA_RESTART
1233 lg %r15,__LC_RESTART_STACK
1234 xc STACK_FRAME_OVERHEAD(__PT_SIZE,%r15),STACK_FRAME_OVERHEAD(%r15)
1235 stmg %r0,%r14,STACK_FRAME_OVERHEAD+__PT_R0(%r15)
1236 mvc STACK_FRAME_OVERHEAD+__PT_R15(8,%r15),__LC_SAVE_AREA_RESTART
1237 mvc STACK_FRAME_OVERHEAD+__PT_PSW(16,%r15),__LC_RST_OLD_PSW
1238 xc 0(STACK_FRAME_OVERHEAD,%r15),0(%r15)
1239 lg %r1,__LC_RESTART_FN # load fn, parm & source cpu
1240 lg %r2,__LC_RESTART_DATA
1241 lg %r3,__LC_RESTART_SOURCE
1242 ltgr %r3,%r3 # test source cpu address
1243 jm 1f # negative -> skip source stop
1244 0: sigp %r4,%r3,SIGP_SENSE # sigp sense to source cpu
1245 brc 10,0b # wait for status stored
1246 1: basr %r14,%r1 # call function
1247 stap __SF_EMPTY(%r15) # store cpu address
1248 llgh %r3,__SF_EMPTY(%r15)
1249 2: sigp %r4,%r3,SIGP_STOP # sigp stop to current cpu
1250 brc 2,2b
1251 3: j 3b
1252 ENDPROC(restart_int_handler)
1254 .section .kprobes.text, "ax"
1256 #if defined(CONFIG_CHECK_STACK) || defined(CONFIG_VMAP_STACK)
1257 /*
1258 * The synchronous or the asynchronous stack overflowed. We are dead.
1259 * No need to properly save the registers, we are going to panic anyway.
1260 * Setup a pt_regs so that show_trace can provide a good call trace.
1261 */
1262 ENTRY(stack_overflow)
1263 lg %r15,__LC_NODAT_STACK # change to panic stack
1264 la %r11,STACK_FRAME_OVERHEAD(%r15)
1265 stmg %r0,%r7,__PT_R0(%r11)
1266 stmg %r8,%r9,__PT_PSW(%r11)
1267 mvc __PT_R8(64,%r11),0(%r14)
1268 stg %r10,__PT_ORIG_GPR2(%r11) # store last break to orig_gpr2
1269 xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
1270 lgr %r2,%r11 # pass pointer to pt_regs
1271 jg kernel_stack_overflow
1272 ENDPROC(stack_overflow)
1273 #endif
1275 ENTRY(cleanup_critical)
1276 #if IS_ENABLED(CONFIG_KVM)
1277 clg %r9,BASED(.Lcleanup_table_sie) # .Lsie_gmap
1278 jl 0f
1279 clg %r9,BASED(.Lcleanup_table_sie+8)# .Lsie_done
1280 jl .Lcleanup_sie
1281 #endif
1282 clg %r9,BASED(.Lcleanup_table) # system_call
1283 jl 0f
1284 clg %r9,BASED(.Lcleanup_table+8) # .Lsysc_do_svc
1285 jl .Lcleanup_system_call
1286 clg %r9,BASED(.Lcleanup_table+16) # .Lsysc_tif
1287 jl 0f
1288 clg %r9,BASED(.Lcleanup_table+24) # .Lsysc_restore
1289 jl .Lcleanup_sysc_tif
1290 clg %r9,BASED(.Lcleanup_table+32) # .Lsysc_done
1291 jl .Lcleanup_sysc_restore
1292 clg %r9,BASED(.Lcleanup_table+40) # .Lio_tif
1293 jl 0f
1294 clg %r9,BASED(.Lcleanup_table+48) # .Lio_restore
1295 jl .Lcleanup_io_tif
1296 clg %r9,BASED(.Lcleanup_table+56) # .Lio_done
1297 jl .Lcleanup_io_restore
1298 clg %r9,BASED(.Lcleanup_table+64) # psw_idle
1299 jl 0f
1300 clg %r9,BASED(.Lcleanup_table+72) # .Lpsw_idle_end
1301 jl .Lcleanup_idle
1302 clg %r9,BASED(.Lcleanup_table+80) # save_fpu_regs
1303 jl 0f
1304 clg %r9,BASED(.Lcleanup_table+88) # .Lsave_fpu_regs_end
1305 jl .Lcleanup_save_fpu_regs
1306 clg %r9,BASED(.Lcleanup_table+96) # load_fpu_regs
1307 jl 0f
1308 clg %r9,BASED(.Lcleanup_table+104) # .Lload_fpu_regs_end
1309 jl .Lcleanup_load_fpu_regs
1310 0: BR_EX %r14,%r11
1311 ENDPROC(cleanup_critical)
1313 .align 8
1314 .Lcleanup_table:
1315 .quad system_call
1316 .quad .Lsysc_do_svc
1317 .quad .Lsysc_tif
1318 .quad .Lsysc_restore
1319 .quad .Lsysc_done
1320 .quad .Lio_tif
1321 .quad .Lio_restore
1322 .quad .Lio_done
1323 .quad psw_idle
1324 .quad .Lpsw_idle_end
1325 .quad save_fpu_regs
1326 .quad .Lsave_fpu_regs_end
1327 .quad load_fpu_regs
1328 .quad .Lload_fpu_regs_end
1330 #if IS_ENABLED(CONFIG_KVM)
1331 .Lcleanup_table_sie:
1332 .quad .Lsie_gmap
1333 .quad .Lsie_done
1335 .Lcleanup_sie:
1336 cghi %r11,__LC_SAVE_AREA_ASYNC #Is this in normal interrupt?
1337 je 1f
1338 slg %r9,BASED(.Lsie_crit_mcck_start)
1339 clg %r9,BASED(.Lsie_crit_mcck_length)
1340 jh 1f
1341 oi __LC_CPU_FLAGS+7, _CIF_MCCK_GUEST
1342 1: BPENTER __SF_SIE_FLAGS(%r15),(_TIF_ISOLATE_BP|_TIF_ISOLATE_BP_GUEST)
1343 lg %r9,__SF_SIE_CONTROL(%r15) # get control block pointer
1344 ni __SIE_PROG0C+3(%r9),0xfe # no longer in SIE
1345 lctlg %c1,%c1,__LC_USER_ASCE # load primary asce
1346 larl %r9,sie_exit # skip forward to sie_exit
1347 BR_EX %r14,%r11
1348 #endif
1350 .Lcleanup_system_call:
1351 # check if stpt has been executed
1352 clg %r9,BASED(.Lcleanup_system_call_insn)
1353 jh 0f
1354 mvc __LC_SYNC_ENTER_TIMER(8),__LC_ASYNC_ENTER_TIMER
1355 cghi %r11,__LC_SAVE_AREA_ASYNC
1356 je 0f
1357 mvc __LC_SYNC_ENTER_TIMER(8),__LC_MCCK_ENTER_TIMER
1358 0: # check if stmg has been executed
1359 clg %r9,BASED(.Lcleanup_system_call_insn+8)
1360 jh 0f
1361 mvc __LC_SAVE_AREA_SYNC(64),0(%r11)
1362 0: # check if base register setup + TIF bit load has been done
1363 clg %r9,BASED(.Lcleanup_system_call_insn+16)
1364 jhe 0f
1365 # set up saved register r12 task struct pointer
1366 stg %r12,32(%r11)
1367 # set up saved register r13 __TASK_thread offset
1368 mvc 40(8,%r11),BASED(.Lcleanup_system_call_const)
1369 0: # check if the user time update has been done
1370 clg %r9,BASED(.Lcleanup_system_call_insn+24)
1371 jh 0f
1372 lg %r15,__LC_EXIT_TIMER
1373 slg %r15,__LC_SYNC_ENTER_TIMER
1374 alg %r15,__LC_USER_TIMER
1375 stg %r15,__LC_USER_TIMER
1376 0: # check if the system time update has been done
1377 clg %r9,BASED(.Lcleanup_system_call_insn+32)
1378 jh 0f
1379 lg %r15,__LC_LAST_UPDATE_TIMER
1380 slg %r15,__LC_EXIT_TIMER
1381 alg %r15,__LC_SYSTEM_TIMER
1382 stg %r15,__LC_SYSTEM_TIMER
1383 0: # update accounting time stamp
1384 mvc __LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
1385 BPENTER __TI_flags(%r12),_TIF_ISOLATE_BP
1386 # set up saved register r11
1387 lg %r15,__LC_KERNEL_STACK
1388 la %r9,STACK_FRAME_OVERHEAD(%r15)
1389 stg %r9,24(%r11) # r11 pt_regs pointer
1390 # fill pt_regs
1391 mvc __PT_R8(64,%r9),__LC_SAVE_AREA_SYNC
1392 stmg %r0,%r7,__PT_R0(%r9)
1393 mvc __PT_PSW(16,%r9),__LC_SVC_OLD_PSW
1394 mvc __PT_INT_CODE(4,%r9),__LC_SVC_ILC
1395 xc __PT_FLAGS(8,%r9),__PT_FLAGS(%r9)
1396 mvi __PT_FLAGS+7(%r9),_PIF_SYSCALL
1397 # setup saved register r15
1398 stg %r15,56(%r11) # r15 stack pointer
1399 # set new psw address and exit
1400 larl %r9,.Lsysc_do_svc
1401 BR_EX %r14,%r11
1402 .Lcleanup_system_call_insn:
1403 .quad system_call
1404 .quad .Lsysc_stmg
1405 .quad .Lsysc_per
1406 .quad .Lsysc_vtime+36
1407 .quad .Lsysc_vtime+42
1408 .Lcleanup_system_call_const:
1409 .quad __TASK_thread
1411 .Lcleanup_sysc_tif:
1412 larl %r9,.Lsysc_tif
1413 BR_EX %r14,%r11
1415 .Lcleanup_sysc_restore:
1416 # check if stpt has been executed
1417 clg %r9,BASED(.Lcleanup_sysc_restore_insn)
1418 jh 0f
1419 mvc __LC_EXIT_TIMER(8),__LC_ASYNC_ENTER_TIMER
1420 cghi %r11,__LC_SAVE_AREA_ASYNC
1421 je 0f
1422 mvc __LC_EXIT_TIMER(8),__LC_MCCK_ENTER_TIMER
1423 0: clg %r9,BASED(.Lcleanup_sysc_restore_insn+8)
1424 je 1f
1425 lg %r9,24(%r11) # get saved pointer to pt_regs
1426 mvc __LC_RETURN_PSW(16),__PT_PSW(%r9)
1427 mvc 0(64,%r11),__PT_R8(%r9)
1428 lmg %r0,%r7,__PT_R0(%r9)
1429 1: lmg %r8,%r9,__LC_RETURN_PSW
1430 BR_EX %r14,%r11
1431 .Lcleanup_sysc_restore_insn:
1432 .quad .Lsysc_exit_timer
1433 .quad .Lsysc_done - 4
1435 .Lcleanup_io_tif:
1436 larl %r9,.Lio_tif
1437 BR_EX %r14,%r11
1439 .Lcleanup_io_restore:
1440 # check if stpt has been executed
1441 clg %r9,BASED(.Lcleanup_io_restore_insn)
1442 jh 0f
1443 mvc __LC_EXIT_TIMER(8),__LC_MCCK_ENTER_TIMER
1444 0: clg %r9,BASED(.Lcleanup_io_restore_insn+8)
1445 je 1f
1446 lg %r9,24(%r11) # get saved r11 pointer to pt_regs
1447 mvc __LC_RETURN_PSW(16),__PT_PSW(%r9)
1448 mvc 0(64,%r11),__PT_R8(%r9)
1449 lmg %r0,%r7,__PT_R0(%r9)
1450 1: lmg %r8,%r9,__LC_RETURN_PSW
1451 BR_EX %r14,%r11
1452 .Lcleanup_io_restore_insn:
1453 .quad .Lio_exit_timer
1454 .quad .Lio_done - 4
1456 .Lcleanup_idle:
1457 ni __LC_CPU_FLAGS+7,255-_CIF_ENABLED_WAIT
1458 # copy interrupt clock & cpu timer
1459 mvc __CLOCK_IDLE_EXIT(8,%r2),__LC_INT_CLOCK
1460 mvc __TIMER_IDLE_EXIT(8,%r2),__LC_ASYNC_ENTER_TIMER
1461 cghi %r11,__LC_SAVE_AREA_ASYNC
1462 je 0f
1463 mvc __CLOCK_IDLE_EXIT(8,%r2),__LC_MCCK_CLOCK
1464 mvc __TIMER_IDLE_EXIT(8,%r2),__LC_MCCK_ENTER_TIMER
1465 0: # check if stck & stpt have been executed
1466 clg %r9,BASED(.Lcleanup_idle_insn)
1467 jhe 1f
1468 mvc __CLOCK_IDLE_ENTER(8,%r2),__CLOCK_IDLE_EXIT(%r2)
1469 mvc __TIMER_IDLE_ENTER(8,%r2),__TIMER_IDLE_EXIT(%r2)
1470 1: # calculate idle cycles
1471 #ifdef CONFIG_SMP
1472 clg %r9,BASED(.Lcleanup_idle_insn)
1473 jl 3f
1474 larl %r1,smp_cpu_mtid
1475 llgf %r1,0(%r1)
1476 ltgr %r1,%r1
1477 jz 3f
1478 .insn rsy,0xeb0000000017,%r1,5,__SF_EMPTY+80(%r15)
1479 larl %r3,mt_cycles
1480 ag %r3,__LC_PERCPU_OFFSET
1481 la %r4,__SF_EMPTY+16(%r15)
1482 2: lg %r0,0(%r3)
1483 slg %r0,0(%r4)
1484 alg %r0,64(%r4)
1485 stg %r0,0(%r3)
1486 la %r3,8(%r3)
1487 la %r4,8(%r4)
1488 brct %r1,2b
1489 #endif
1490 3: # account system time going idle
1491 lg %r9,__LC_STEAL_TIMER
1492 alg %r9,__CLOCK_IDLE_ENTER(%r2)
1493 slg %r9,__LC_LAST_UPDATE_CLOCK
1494 stg %r9,__LC_STEAL_TIMER
1495 mvc __LC_LAST_UPDATE_CLOCK(8),__CLOCK_IDLE_EXIT(%r2)
1496 lg %r9,__LC_SYSTEM_TIMER
1497 alg %r9,__LC_LAST_UPDATE_TIMER
1498 slg %r9,__TIMER_IDLE_ENTER(%r2)
1499 stg %r9,__LC_SYSTEM_TIMER
1500 mvc __LC_LAST_UPDATE_TIMER(8),__TIMER_IDLE_EXIT(%r2)
1501 # prepare return psw
1502 nihh %r8,0xfcfd # clear irq & wait state bits
1503 lg %r9,48(%r11) # return from psw_idle
1504 BR_EX %r14,%r11
1505 .Lcleanup_idle_insn:
1506 .quad .Lpsw_idle_lpsw
1508 .Lcleanup_save_fpu_regs:
1509 larl %r9,save_fpu_regs
1510 BR_EX %r14,%r11
1512 .Lcleanup_load_fpu_regs:
1513 larl %r9,load_fpu_regs
1514 BR_EX %r14,%r11
1516 /*
1517 * Integer constants
1518 */
1519 .align 8
1520 .Lcritical_start:
1521 .quad .L__critical_start
1522 .Lcritical_length:
1523 .quad .L__critical_end - .L__critical_start
1524 #if IS_ENABLED(CONFIG_KVM)
1525 .Lsie_critical_start:
1526 .quad .Lsie_gmap
1527 .Lsie_critical_length:
1528 .quad .Lsie_done - .Lsie_gmap
1529 .Lsie_crit_mcck_start:
1530 .quad .Lsie_entry
1531 .Lsie_crit_mcck_length:
1532 .quad .Lsie_skip - .Lsie_entry
1533 #endif
1534 .section .rodata, "a"
1535 #define SYSCALL(esame,emu) .quad __s390x_ ## esame
1536 .globl sys_call_table
1537 sys_call_table:
1538 #include "asm/syscall_table.h"
1539 #undef SYSCALL
1541 #ifdef CONFIG_COMPAT
1543 #define SYSCALL(esame,emu) .quad __s390_ ## emu
1544 .globl sys_call_table_emu
1545 sys_call_table_emu:
1546 #include "asm/syscall_table.h"
1547 #undef SYSCALL
1548 #endif