xref: /linux/arch/s390/kernel/entry.S (revision 0408c58be5a475c99b271f08d85859f7b59ec767)
1/*
2 *    S390 low-level entry points.
3 *
4 *    Copyright IBM Corp. 1999, 2012
5 *    Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
6 *		 Hartmut Penner (hp@de.ibm.com),
7 *		 Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com),
8 *		 Heiko Carstens <heiko.carstens@de.ibm.com>
9 */
10
11#include <linux/init.h>
12#include <linux/linkage.h>
13#include <asm/processor.h>
14#include <asm/cache.h>
15#include <asm/errno.h>
16#include <asm/ptrace.h>
17#include <asm/thread_info.h>
18#include <asm/asm-offsets.h>
19#include <asm/unistd.h>
20#include <asm/page.h>
21#include <asm/sigp.h>
22#include <asm/irq.h>
23#include <asm/vx-insn.h>
24#include <asm/setup.h>
25#include <asm/nmi.h>
26#include <asm/export.h>
27
28__PT_R0      =	__PT_GPRS
29__PT_R1      =	__PT_GPRS + 8
30__PT_R2      =	__PT_GPRS + 16
31__PT_R3      =	__PT_GPRS + 24
32__PT_R4      =	__PT_GPRS + 32
33__PT_R5      =	__PT_GPRS + 40
34__PT_R6      =	__PT_GPRS + 48
35__PT_R7      =	__PT_GPRS + 56
36__PT_R8      =	__PT_GPRS + 64
37__PT_R9      =	__PT_GPRS + 72
38__PT_R10     =	__PT_GPRS + 80
39__PT_R11     =	__PT_GPRS + 88
40__PT_R12     =	__PT_GPRS + 96
41__PT_R13     =	__PT_GPRS + 104
42__PT_R14     =	__PT_GPRS + 112
43__PT_R15     =	__PT_GPRS + 120
44
45STACK_SHIFT = PAGE_SHIFT + THREAD_SIZE_ORDER
46STACK_SIZE  = 1 << STACK_SHIFT
47STACK_INIT = STACK_SIZE - STACK_FRAME_OVERHEAD - __PT_SIZE
48
49_TIF_WORK	= (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_NEED_RESCHED | \
50		   _TIF_UPROBE | _TIF_GUARDED_STORAGE | _TIF_PATCH_PENDING)
51_TIF_TRACE	= (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | _TIF_SECCOMP | \
52		   _TIF_SYSCALL_TRACEPOINT)
53_CIF_WORK	= (_CIF_MCCK_PENDING | _CIF_ASCE_PRIMARY | \
54		   _CIF_ASCE_SECONDARY | _CIF_FPU)
55_PIF_WORK	= (_PIF_PER_TRAP)
56
57#define BASED(name) name-cleanup_critical(%r13)
58
59	.macro	TRACE_IRQS_ON
60#ifdef CONFIG_TRACE_IRQFLAGS
61	basr	%r2,%r0
62	brasl	%r14,trace_hardirqs_on_caller
63#endif
64	.endm
65
66	.macro	TRACE_IRQS_OFF
67#ifdef CONFIG_TRACE_IRQFLAGS
68	basr	%r2,%r0
69	brasl	%r14,trace_hardirqs_off_caller
70#endif
71	.endm
72
73	.macro	LOCKDEP_SYS_EXIT
74#ifdef CONFIG_LOCKDEP
75	tm	__PT_PSW+1(%r11),0x01	# returning to user ?
76	jz	.+10
77	brasl	%r14,lockdep_sys_exit
78#endif
79	.endm
80
81	.macro	CHECK_STACK stacksize,savearea
82#ifdef CONFIG_CHECK_STACK
83	tml	%r15,\stacksize - CONFIG_STACK_GUARD
84	lghi	%r14,\savearea
85	jz	stack_overflow
86#endif
87	.endm
88
89	.macro	SWITCH_ASYNC savearea,timer
90	tmhh	%r8,0x0001		# interrupting from user ?
91	jnz	1f
92	lgr	%r14,%r9
93	slg	%r14,BASED(.Lcritical_start)
94	clg	%r14,BASED(.Lcritical_length)
95	jhe	0f
96	lghi	%r11,\savearea		# inside critical section, do cleanup
97	brasl	%r14,cleanup_critical
98	tmhh	%r8,0x0001		# retest problem state after cleanup
99	jnz	1f
1000:	lg	%r14,__LC_ASYNC_STACK	# are we already on the async stack?
101	slgr	%r14,%r15
102	srag	%r14,%r14,STACK_SHIFT
103	jnz	2f
104	CHECK_STACK 1<<STACK_SHIFT,\savearea
105	aghi	%r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE)
106	j	3f
1071:	UPDATE_VTIME %r14,%r15,\timer
1082:	lg	%r15,__LC_ASYNC_STACK	# load async stack
1093:	la	%r11,STACK_FRAME_OVERHEAD(%r15)
110	.endm
111
112	.macro UPDATE_VTIME w1,w2,enter_timer
113	lg	\w1,__LC_EXIT_TIMER
114	lg	\w2,__LC_LAST_UPDATE_TIMER
115	slg	\w1,\enter_timer
116	slg	\w2,__LC_EXIT_TIMER
117	alg	\w1,__LC_USER_TIMER
118	alg	\w2,__LC_SYSTEM_TIMER
119	stg	\w1,__LC_USER_TIMER
120	stg	\w2,__LC_SYSTEM_TIMER
121	mvc	__LC_LAST_UPDATE_TIMER(8),\enter_timer
122	.endm
123
124	.macro REENABLE_IRQS
125	stg	%r8,__LC_RETURN_PSW
126	ni	__LC_RETURN_PSW,0xbf
127	ssm	__LC_RETURN_PSW
128	.endm
129
130	.macro STCK savearea
131#ifdef CONFIG_HAVE_MARCH_Z9_109_FEATURES
132	.insn	s,0xb27c0000,\savearea		# store clock fast
133#else
134	.insn	s,0xb2050000,\savearea		# store clock
135#endif
136	.endm
137
138	/*
139	 * The TSTMSK macro generates a test-under-mask instruction by
140	 * calculating the memory offset for the specified mask value.
141	 * Mask value can be any constant.  The macro shifts the mask
142	 * value to calculate the memory offset for the test-under-mask
143	 * instruction.
144	 */
145	.macro TSTMSK addr, mask, size=8, bytepos=0
146		.if (\bytepos < \size) && (\mask >> 8)
147			.if (\mask & 0xff)
148				.error "Mask exceeds byte boundary"
149			.endif
150			TSTMSK \addr, "(\mask >> 8)", \size, "(\bytepos + 1)"
151			.exitm
152		.endif
153		.ifeq \mask
154			.error "Mask must not be zero"
155		.endif
156		off = \size - \bytepos - 1
157		tm	off+\addr, \mask
158	.endm
159
160	.section .kprobes.text, "ax"
161.Ldummy:
162	/*
163	 * This nop exists only in order to avoid that __switch_to starts at
164	 * the beginning of the kprobes text section. In that case we would
165	 * have several symbols at the same address. E.g. objdump would take
166	 * an arbitrary symbol name when disassembling this code.
167	 * With the added nop in between the __switch_to symbol is unique
168	 * again.
169	 */
170	nop	0
171
172/*
173 * Scheduler resume function, called by switch_to
174 *  gpr2 = (task_struct *) prev
175 *  gpr3 = (task_struct *) next
176 * Returns:
177 *  gpr2 = prev
178 */
179ENTRY(__switch_to)
180	stmg	%r6,%r15,__SF_GPRS(%r15)	# store gprs of prev task
181	lgr	%r1,%r2
182	aghi	%r1,__TASK_thread		# thread_struct of prev task
183	lg	%r5,__TASK_stack(%r3)		# start of kernel stack of next
184	stg	%r15,__THREAD_ksp(%r1)		# store kernel stack of prev
185	lgr	%r1,%r3
186	aghi	%r1,__TASK_thread		# thread_struct of next task
187	lgr	%r15,%r5
188	aghi	%r15,STACK_INIT			# end of kernel stack of next
189	stg	%r3,__LC_CURRENT		# store task struct of next
190	stg	%r15,__LC_KERNEL_STACK		# store end of kernel stack
191	lg	%r15,__THREAD_ksp(%r1)		# load kernel stack of next
192	mvc	__LC_CURRENT_PID(4,%r0),__TASK_pid(%r3) # store pid of next
193	lmg	%r6,%r15,__SF_GPRS(%r15)	# load gprs of next task
194	TSTMSK	__LC_MACHINE_FLAGS,MACHINE_FLAG_LPP
195	bzr	%r14
196	.insn	s,0xb2800000,__LC_LPP		# set program parameter
197	br	%r14
198
199.L__critical_start:
200
201#if IS_ENABLED(CONFIG_KVM)
202/*
203 * sie64a calling convention:
204 * %r2 pointer to sie control block
205 * %r3 guest register save area
206 */
207ENTRY(sie64a)
208	stmg	%r6,%r14,__SF_GPRS(%r15)	# save kernel registers
209	stg	%r2,__SF_EMPTY(%r15)		# save control block pointer
210	stg	%r3,__SF_EMPTY+8(%r15)		# save guest register save area
211	xc	__SF_EMPTY+16(8,%r15),__SF_EMPTY+16(%r15) # reason code = 0
212	TSTMSK	__LC_CPU_FLAGS,_CIF_FPU		# load guest fp/vx registers ?
213	jno	.Lsie_load_guest_gprs
214	brasl	%r14,load_fpu_regs		# load guest fp/vx regs
215.Lsie_load_guest_gprs:
216	lmg	%r0,%r13,0(%r3)			# load guest gprs 0-13
217	lg	%r14,__LC_GMAP			# get gmap pointer
218	ltgr	%r14,%r14
219	jz	.Lsie_gmap
220	lctlg	%c1,%c1,__GMAP_ASCE(%r14)	# load primary asce
221.Lsie_gmap:
222	lg	%r14,__SF_EMPTY(%r15)		# get control block pointer
223	oi	__SIE_PROG0C+3(%r14),1		# we are going into SIE now
224	tm	__SIE_PROG20+3(%r14),3		# last exit...
225	jnz	.Lsie_skip
226	TSTMSK	__LC_CPU_FLAGS,_CIF_FPU
227	jo	.Lsie_skip			# exit if fp/vx regs changed
228	sie	0(%r14)
229.Lsie_skip:
230	ni	__SIE_PROG0C+3(%r14),0xfe	# no longer in SIE
231	lctlg	%c1,%c1,__LC_USER_ASCE		# load primary asce
232.Lsie_done:
233# some program checks are suppressing. C code (e.g. do_protection_exception)
234# will rewind the PSW by the ILC, which is often 4 bytes in case of SIE. There
235# are some corner cases (e.g. runtime instrumentation) where ILC is unpredictable.
236# Other instructions between sie64a and .Lsie_done should not cause program
237# interrupts. So lets use 3 nops as a landing pad for all possible rewinds.
238# See also .Lcleanup_sie
239.Lrewind_pad6:
240	nopr	7
241.Lrewind_pad4:
242	nopr	7
243.Lrewind_pad2:
244	nopr	7
245	.globl sie_exit
246sie_exit:
247	lg	%r14,__SF_EMPTY+8(%r15)		# load guest register save area
248	stmg	%r0,%r13,0(%r14)		# save guest gprs 0-13
249	lmg	%r6,%r14,__SF_GPRS(%r15)	# restore kernel registers
250	lg	%r2,__SF_EMPTY+16(%r15)		# return exit reason code
251	br	%r14
252.Lsie_fault:
253	lghi	%r14,-EFAULT
254	stg	%r14,__SF_EMPTY+16(%r15)	# set exit reason code
255	j	sie_exit
256
257	EX_TABLE(.Lrewind_pad6,.Lsie_fault)
258	EX_TABLE(.Lrewind_pad4,.Lsie_fault)
259	EX_TABLE(.Lrewind_pad2,.Lsie_fault)
260	EX_TABLE(sie_exit,.Lsie_fault)
261EXPORT_SYMBOL(sie64a)
262EXPORT_SYMBOL(sie_exit)
263#endif
264
265/*
266 * SVC interrupt handler routine. System calls are synchronous events and
267 * are executed with interrupts enabled.
268 */
269
270ENTRY(system_call)
271	stpt	__LC_SYNC_ENTER_TIMER
272.Lsysc_stmg:
273	stmg	%r8,%r15,__LC_SAVE_AREA_SYNC
274	lg	%r12,__LC_CURRENT
275	lghi	%r13,__TASK_thread
276	lghi	%r14,_PIF_SYSCALL
277.Lsysc_per:
278	lg	%r15,__LC_KERNEL_STACK
279	la	%r11,STACK_FRAME_OVERHEAD(%r15)	# pointer to pt_regs
280.Lsysc_vtime:
281	UPDATE_VTIME %r8,%r9,__LC_SYNC_ENTER_TIMER
282	stmg	%r0,%r7,__PT_R0(%r11)
283	mvc	__PT_R8(64,%r11),__LC_SAVE_AREA_SYNC
284	mvc	__PT_PSW(16,%r11),__LC_SVC_OLD_PSW
285	mvc	__PT_INT_CODE(4,%r11),__LC_SVC_ILC
286	stg	%r14,__PT_FLAGS(%r11)
287.Lsysc_do_svc:
288	# load address of system call table
289	lg	%r10,__THREAD_sysc_table(%r13,%r12)
290	llgh	%r8,__PT_INT_CODE+2(%r11)
291	slag	%r8,%r8,2			# shift and test for svc 0
292	jnz	.Lsysc_nr_ok
293	# svc 0: system call number in %r1
294	llgfr	%r1,%r1				# clear high word in r1
295	cghi	%r1,NR_syscalls
296	jnl	.Lsysc_nr_ok
297	sth	%r1,__PT_INT_CODE+2(%r11)
298	slag	%r8,%r1,2
299.Lsysc_nr_ok:
300	xc	__SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
301	stg	%r2,__PT_ORIG_GPR2(%r11)
302	stg	%r7,STACK_FRAME_OVERHEAD(%r15)
303	lgf	%r9,0(%r8,%r10)			# get system call add.
304	TSTMSK	__TI_flags(%r12),_TIF_TRACE
305	jnz	.Lsysc_tracesys
306	basr	%r14,%r9			# call sys_xxxx
307	stg	%r2,__PT_R2(%r11)		# store return value
308
309.Lsysc_return:
310	LOCKDEP_SYS_EXIT
311.Lsysc_tif:
312	TSTMSK	__PT_FLAGS(%r11),_PIF_WORK
313	jnz	.Lsysc_work
314	TSTMSK	__TI_flags(%r12),_TIF_WORK
315	jnz	.Lsysc_work			# check for work
316	TSTMSK	__LC_CPU_FLAGS,_CIF_WORK
317	jnz	.Lsysc_work
318.Lsysc_restore:
319	lg	%r14,__LC_VDSO_PER_CPU
320	lmg	%r0,%r10,__PT_R0(%r11)
321	mvc	__LC_RETURN_PSW(16),__PT_PSW(%r11)
322.Lsysc_exit_timer:
323	stpt	__LC_EXIT_TIMER
324	mvc	__VDSO_ECTG_BASE(16,%r14),__LC_EXIT_TIMER
325	lmg	%r11,%r15,__PT_R11(%r11)
326	lpswe	__LC_RETURN_PSW
327.Lsysc_done:
328
329#
330# One of the work bits is on. Find out which one.
331#
332.Lsysc_work:
333	TSTMSK	__LC_CPU_FLAGS,_CIF_MCCK_PENDING
334	jo	.Lsysc_mcck_pending
335	TSTMSK	__TI_flags(%r12),_TIF_NEED_RESCHED
336	jo	.Lsysc_reschedule
337#ifdef CONFIG_UPROBES
338	TSTMSK	__TI_flags(%r12),_TIF_UPROBE
339	jo	.Lsysc_uprobe_notify
340#endif
341	TSTMSK	__TI_flags(%r12),_TIF_GUARDED_STORAGE
342	jo	.Lsysc_guarded_storage
343	TSTMSK	__PT_FLAGS(%r11),_PIF_PER_TRAP
344	jo	.Lsysc_singlestep
345#ifdef CONFIG_LIVEPATCH
346	TSTMSK	__TI_flags(%r12),_TIF_PATCH_PENDING
347	jo	.Lsysc_patch_pending	# handle live patching just before
348					# signals and possible syscall restart
349#endif
350	TSTMSK	__TI_flags(%r12),_TIF_SIGPENDING
351	jo	.Lsysc_sigpending
352	TSTMSK	__TI_flags(%r12),_TIF_NOTIFY_RESUME
353	jo	.Lsysc_notify_resume
354	TSTMSK	__LC_CPU_FLAGS,_CIF_FPU
355	jo	.Lsysc_vxrs
356	TSTMSK	__LC_CPU_FLAGS,(_CIF_ASCE_PRIMARY|_CIF_ASCE_SECONDARY)
357	jnz	.Lsysc_asce
358	j	.Lsysc_return		# beware of critical section cleanup
359
360#
361# _TIF_NEED_RESCHED is set, call schedule
362#
363.Lsysc_reschedule:
364	larl	%r14,.Lsysc_return
365	jg	schedule
366
367#
368# _CIF_MCCK_PENDING is set, call handler
369#
370.Lsysc_mcck_pending:
371	larl	%r14,.Lsysc_return
372	jg	s390_handle_mcck	# TIF bit will be cleared by handler
373
374#
375# _CIF_ASCE_PRIMARY and/or CIF_ASCE_SECONDARY set, load user space asce
376#
377.Lsysc_asce:
378	ni	__LC_CPU_FLAGS+7,255-_CIF_ASCE_PRIMARY
379	lctlg	%c1,%c1,__LC_USER_ASCE		# load primary asce
380	TSTMSK	__LC_CPU_FLAGS,_CIF_ASCE_SECONDARY
381	jz	.Lsysc_return
382	larl	%r14,.Lsysc_return
383	jg	set_fs_fixup
384
385#
386# CIF_FPU is set, restore floating-point controls and floating-point registers.
387#
388.Lsysc_vxrs:
389	larl	%r14,.Lsysc_return
390	jg	load_fpu_regs
391
392#
393# _TIF_SIGPENDING is set, call do_signal
394#
395.Lsysc_sigpending:
396	lgr	%r2,%r11		# pass pointer to pt_regs
397	brasl	%r14,do_signal
398	TSTMSK	__PT_FLAGS(%r11),_PIF_SYSCALL
399	jno	.Lsysc_return
400.Lsysc_do_syscall:
401	lghi	%r13,__TASK_thread
402	lmg	%r2,%r7,__PT_R2(%r11)	# load svc arguments
403	lghi	%r1,0			# svc 0 returns -ENOSYS
404	j	.Lsysc_do_svc
405
406#
407# _TIF_NOTIFY_RESUME is set, call do_notify_resume
408#
409.Lsysc_notify_resume:
410	lgr	%r2,%r11		# pass pointer to pt_regs
411	larl	%r14,.Lsysc_return
412	jg	do_notify_resume
413
414#
415# _TIF_UPROBE is set, call uprobe_notify_resume
416#
417#ifdef CONFIG_UPROBES
418.Lsysc_uprobe_notify:
419	lgr	%r2,%r11		# pass pointer to pt_regs
420	larl	%r14,.Lsysc_return
421	jg	uprobe_notify_resume
422#endif
423
424#
425# _TIF_GUARDED_STORAGE is set, call guarded_storage_load
426#
427.Lsysc_guarded_storage:
428	lgr	%r2,%r11		# pass pointer to pt_regs
429	larl	%r14,.Lsysc_return
430	jg	gs_load_bc_cb
431#
432# _TIF_PATCH_PENDING is set, call klp_update_patch_state
433#
434#ifdef CONFIG_LIVEPATCH
435.Lsysc_patch_pending:
436	lg	%r2,__LC_CURRENT	# pass pointer to task struct
437	larl	%r14,.Lsysc_return
438	jg	klp_update_patch_state
439#endif
440
441#
442# _PIF_PER_TRAP is set, call do_per_trap
443#
444.Lsysc_singlestep:
445	ni	__PT_FLAGS+7(%r11),255-_PIF_PER_TRAP
446	lgr	%r2,%r11		# pass pointer to pt_regs
447	larl	%r14,.Lsysc_return
448	jg	do_per_trap
449
450#
451# call tracehook_report_syscall_entry/tracehook_report_syscall_exit before
452# and after the system call
453#
454.Lsysc_tracesys:
455	lgr	%r2,%r11		# pass pointer to pt_regs
456	la	%r3,0
457	llgh	%r0,__PT_INT_CODE+2(%r11)
458	stg	%r0,__PT_R2(%r11)
459	brasl	%r14,do_syscall_trace_enter
460	lghi	%r0,NR_syscalls
461	clgr	%r0,%r2
462	jnh	.Lsysc_tracenogo
463	sllg	%r8,%r2,2
464	lgf	%r9,0(%r8,%r10)
465.Lsysc_tracego:
466	lmg	%r3,%r7,__PT_R3(%r11)
467	stg	%r7,STACK_FRAME_OVERHEAD(%r15)
468	lg	%r2,__PT_ORIG_GPR2(%r11)
469	basr	%r14,%r9		# call sys_xxx
470	stg	%r2,__PT_R2(%r11)	# store return value
471.Lsysc_tracenogo:
472	TSTMSK	__TI_flags(%r12),_TIF_TRACE
473	jz	.Lsysc_return
474	lgr	%r2,%r11		# pass pointer to pt_regs
475	larl	%r14,.Lsysc_return
476	jg	do_syscall_trace_exit
477
478#
479# a new process exits the kernel with ret_from_fork
480#
481ENTRY(ret_from_fork)
482	la	%r11,STACK_FRAME_OVERHEAD(%r15)
483	lg	%r12,__LC_CURRENT
484	brasl	%r14,schedule_tail
485	TRACE_IRQS_ON
486	ssm	__LC_SVC_NEW_PSW	# reenable interrupts
487	tm	__PT_PSW+1(%r11),0x01	# forking a kernel thread ?
488	jne	.Lsysc_tracenogo
489	# it's a kernel thread
490	lmg	%r9,%r10,__PT_R9(%r11)	# load gprs
491ENTRY(kernel_thread_starter)
492	la	%r2,0(%r10)
493	basr	%r14,%r9
494	j	.Lsysc_tracenogo
495
496/*
497 * Program check handler routine
498 */
499
500ENTRY(pgm_check_handler)
501	stpt	__LC_SYNC_ENTER_TIMER
502	stmg	%r8,%r15,__LC_SAVE_AREA_SYNC
503	lg	%r10,__LC_LAST_BREAK
504	lg	%r12,__LC_CURRENT
505	larl	%r13,cleanup_critical
506	lmg	%r8,%r9,__LC_PGM_OLD_PSW
507	tmhh	%r8,0x0001		# test problem state bit
508	jnz	2f			# -> fault in user space
509#if IS_ENABLED(CONFIG_KVM)
510	# cleanup critical section for sie64a
511	lgr	%r14,%r9
512	slg	%r14,BASED(.Lsie_critical_start)
513	clg	%r14,BASED(.Lsie_critical_length)
514	jhe	0f
515	brasl	%r14,.Lcleanup_sie
516#endif
5170:	tmhh	%r8,0x4000		# PER bit set in old PSW ?
518	jnz	1f			# -> enabled, can't be a double fault
519	tm	__LC_PGM_ILC+3,0x80	# check for per exception
520	jnz	.Lpgm_svcper		# -> single stepped svc
5211:	CHECK_STACK STACK_SIZE,__LC_SAVE_AREA_SYNC
522	aghi	%r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE)
523	j	4f
5242:	UPDATE_VTIME %r14,%r15,__LC_SYNC_ENTER_TIMER
525	lg	%r15,__LC_KERNEL_STACK
526	lgr	%r14,%r12
527	aghi	%r14,__TASK_thread	# pointer to thread_struct
528	lghi	%r13,__LC_PGM_TDB
529	tm	__LC_PGM_ILC+2,0x02	# check for transaction abort
530	jz	3f
531	mvc	__THREAD_trap_tdb(256,%r14),0(%r13)
5323:	stg	%r10,__THREAD_last_break(%r14)
5334:	la	%r11,STACK_FRAME_OVERHEAD(%r15)
534	stmg	%r0,%r7,__PT_R0(%r11)
535	mvc	__PT_R8(64,%r11),__LC_SAVE_AREA_SYNC
536	stmg	%r8,%r9,__PT_PSW(%r11)
537	mvc	__PT_INT_CODE(4,%r11),__LC_PGM_ILC
538	mvc	__PT_INT_PARM_LONG(8,%r11),__LC_TRANS_EXC_CODE
539	xc	__PT_FLAGS(8,%r11),__PT_FLAGS(%r11)
540	stg	%r10,__PT_ARGS(%r11)
541	tm	__LC_PGM_ILC+3,0x80	# check for per exception
542	jz	5f
543	tmhh	%r8,0x0001		# kernel per event ?
544	jz	.Lpgm_kprobe
545	oi	__PT_FLAGS+7(%r11),_PIF_PER_TRAP
546	mvc	__THREAD_per_address(8,%r14),__LC_PER_ADDRESS
547	mvc	__THREAD_per_cause(2,%r14),__LC_PER_CODE
548	mvc	__THREAD_per_paid(1,%r14),__LC_PER_ACCESS_ID
5495:	REENABLE_IRQS
550	xc	__SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
551	larl	%r1,pgm_check_table
552	llgh	%r10,__PT_INT_CODE+2(%r11)
553	nill	%r10,0x007f
554	sll	%r10,2
555	je	.Lpgm_return
556	lgf	%r1,0(%r10,%r1)		# load address of handler routine
557	lgr	%r2,%r11		# pass pointer to pt_regs
558	basr	%r14,%r1		# branch to interrupt-handler
559.Lpgm_return:
560	LOCKDEP_SYS_EXIT
561	tm	__PT_PSW+1(%r11),0x01	# returning to user ?
562	jno	.Lsysc_restore
563	TSTMSK	__PT_FLAGS(%r11),_PIF_SYSCALL
564	jo	.Lsysc_do_syscall
565	j	.Lsysc_tif
566
567#
568# PER event in supervisor state, must be kprobes
569#
570.Lpgm_kprobe:
571	REENABLE_IRQS
572	xc	__SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
573	lgr	%r2,%r11		# pass pointer to pt_regs
574	brasl	%r14,do_per_trap
575	j	.Lpgm_return
576
577#
578# single stepped system call
579#
580.Lpgm_svcper:
581	mvc	__LC_RETURN_PSW(8),__LC_SVC_NEW_PSW
582	lghi	%r13,__TASK_thread
583	larl	%r14,.Lsysc_per
584	stg	%r14,__LC_RETURN_PSW+8
585	lghi	%r14,_PIF_SYSCALL | _PIF_PER_TRAP
586	lpswe	__LC_RETURN_PSW		# branch to .Lsysc_per and enable irqs
587
588/*
589 * IO interrupt handler routine
590 */
591ENTRY(io_int_handler)
592	STCK	__LC_INT_CLOCK
593	stpt	__LC_ASYNC_ENTER_TIMER
594	stmg	%r8,%r15,__LC_SAVE_AREA_ASYNC
595	lg	%r12,__LC_CURRENT
596	larl	%r13,cleanup_critical
597	lmg	%r8,%r9,__LC_IO_OLD_PSW
598	SWITCH_ASYNC __LC_SAVE_AREA_ASYNC,__LC_ASYNC_ENTER_TIMER
599	stmg	%r0,%r7,__PT_R0(%r11)
600	mvc	__PT_R8(64,%r11),__LC_SAVE_AREA_ASYNC
601	stmg	%r8,%r9,__PT_PSW(%r11)
602	mvc	__PT_INT_CODE(12,%r11),__LC_SUBCHANNEL_ID
603	xc	__PT_FLAGS(8,%r11),__PT_FLAGS(%r11)
604	TSTMSK	__LC_CPU_FLAGS,_CIF_IGNORE_IRQ
605	jo	.Lio_restore
606	TRACE_IRQS_OFF
607	xc	__SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
608.Lio_loop:
609	lgr	%r2,%r11		# pass pointer to pt_regs
610	lghi	%r3,IO_INTERRUPT
611	tm	__PT_INT_CODE+8(%r11),0x80	# adapter interrupt ?
612	jz	.Lio_call
613	lghi	%r3,THIN_INTERRUPT
614.Lio_call:
615	brasl	%r14,do_IRQ
616	TSTMSK	__LC_MACHINE_FLAGS,MACHINE_FLAG_LPAR
617	jz	.Lio_return
618	tpi	0
619	jz	.Lio_return
620	mvc	__PT_INT_CODE(12,%r11),__LC_SUBCHANNEL_ID
621	j	.Lio_loop
622.Lio_return:
623	LOCKDEP_SYS_EXIT
624	TRACE_IRQS_ON
625.Lio_tif:
626	TSTMSK	__TI_flags(%r12),_TIF_WORK
627	jnz	.Lio_work		# there is work to do (signals etc.)
628	TSTMSK	__LC_CPU_FLAGS,_CIF_WORK
629	jnz	.Lio_work
630.Lio_restore:
631	lg	%r14,__LC_VDSO_PER_CPU
632	lmg	%r0,%r10,__PT_R0(%r11)
633	mvc	__LC_RETURN_PSW(16),__PT_PSW(%r11)
634.Lio_exit_timer:
635	stpt	__LC_EXIT_TIMER
636	mvc	__VDSO_ECTG_BASE(16,%r14),__LC_EXIT_TIMER
637	lmg	%r11,%r15,__PT_R11(%r11)
638	lpswe	__LC_RETURN_PSW
639.Lio_done:
640
641#
642# There is work todo, find out in which context we have been interrupted:
643# 1) if we return to user space we can do all _TIF_WORK work
644# 2) if we return to kernel code and kvm is enabled check if we need to
645#    modify the psw to leave SIE
646# 3) if we return to kernel code and preemptive scheduling is enabled check
647#    the preemption counter and if it is zero call preempt_schedule_irq
648# Before any work can be done, a switch to the kernel stack is required.
649#
650.Lio_work:
651	tm	__PT_PSW+1(%r11),0x01	# returning to user ?
652	jo	.Lio_work_user		# yes -> do resched & signal
653#ifdef CONFIG_PREEMPT
654	# check for preemptive scheduling
655	icm	%r0,15,__LC_PREEMPT_COUNT
656	jnz	.Lio_restore		# preemption is disabled
657	TSTMSK	__TI_flags(%r12),_TIF_NEED_RESCHED
658	jno	.Lio_restore
659	# switch to kernel stack
660	lg	%r1,__PT_R15(%r11)
661	aghi	%r1,-(STACK_FRAME_OVERHEAD + __PT_SIZE)
662	mvc	STACK_FRAME_OVERHEAD(__PT_SIZE,%r1),0(%r11)
663	xc	__SF_BACKCHAIN(8,%r1),__SF_BACKCHAIN(%r1)
664	la	%r11,STACK_FRAME_OVERHEAD(%r1)
665	lgr	%r15,%r1
666	# TRACE_IRQS_ON already done at .Lio_return, call
667	# TRACE_IRQS_OFF to keep things symmetrical
668	TRACE_IRQS_OFF
669	brasl	%r14,preempt_schedule_irq
670	j	.Lio_return
671#else
672	j	.Lio_restore
673#endif
674
675#
676# Need to do work before returning to userspace, switch to kernel stack
677#
678.Lio_work_user:
679	lg	%r1,__LC_KERNEL_STACK
680	mvc	STACK_FRAME_OVERHEAD(__PT_SIZE,%r1),0(%r11)
681	xc	__SF_BACKCHAIN(8,%r1),__SF_BACKCHAIN(%r1)
682	la	%r11,STACK_FRAME_OVERHEAD(%r1)
683	lgr	%r15,%r1
684
685#
686# One of the work bits is on. Find out which one.
687#
688.Lio_work_tif:
689	TSTMSK	__LC_CPU_FLAGS,_CIF_MCCK_PENDING
690	jo	.Lio_mcck_pending
691	TSTMSK	__TI_flags(%r12),_TIF_NEED_RESCHED
692	jo	.Lio_reschedule
693#ifdef CONFIG_LIVEPATCH
694	TSTMSK	__TI_flags(%r12),_TIF_PATCH_PENDING
695	jo	.Lio_patch_pending
696#endif
697	TSTMSK	__TI_flags(%r12),_TIF_SIGPENDING
698	jo	.Lio_sigpending
699	TSTMSK	__TI_flags(%r12),_TIF_NOTIFY_RESUME
700	jo	.Lio_notify_resume
701	TSTMSK	__TI_flags(%r12),_TIF_GUARDED_STORAGE
702	jo	.Lio_guarded_storage
703	TSTMSK	__LC_CPU_FLAGS,_CIF_FPU
704	jo	.Lio_vxrs
705	TSTMSK	__LC_CPU_FLAGS,(_CIF_ASCE_PRIMARY|_CIF_ASCE_SECONDARY)
706	jnz	.Lio_asce
707	j	.Lio_return		# beware of critical section cleanup
708
709#
710# _CIF_MCCK_PENDING is set, call handler
711#
712.Lio_mcck_pending:
713	# TRACE_IRQS_ON already done at .Lio_return
714	brasl	%r14,s390_handle_mcck	# TIF bit will be cleared by handler
715	TRACE_IRQS_OFF
716	j	.Lio_return
717
718#
719# _CIF_ASCE_PRIMARY and/or CIF_ASCE_SECONDARY set, load user space asce
720#
721.Lio_asce:
722	ni	__LC_CPU_FLAGS+7,255-_CIF_ASCE_PRIMARY
723	lctlg	%c1,%c1,__LC_USER_ASCE		# load primary asce
724	TSTMSK	__LC_CPU_FLAGS,_CIF_ASCE_SECONDARY
725	jz	.Lio_return
726	larl	%r14,.Lio_return
727	jg	set_fs_fixup
728
729#
730# CIF_FPU is set, restore floating-point controls and floating-point registers.
731#
732.Lio_vxrs:
733	larl	%r14,.Lio_return
734	jg	load_fpu_regs
735
736#
737# _TIF_GUARDED_STORAGE is set, call guarded_storage_load
738#
739.Lio_guarded_storage:
740	# TRACE_IRQS_ON already done at .Lio_return
741	ssm	__LC_SVC_NEW_PSW	# reenable interrupts
742	lgr	%r2,%r11		# pass pointer to pt_regs
743	brasl	%r14,gs_load_bc_cb
744	ssm	__LC_PGM_NEW_PSW	# disable I/O and ext. interrupts
745	TRACE_IRQS_OFF
746	j	.Lio_return
747
748#
749# _TIF_NEED_RESCHED is set, call schedule
750#
751.Lio_reschedule:
752	# TRACE_IRQS_ON already done at .Lio_return
753	ssm	__LC_SVC_NEW_PSW	# reenable interrupts
754	brasl	%r14,schedule		# call scheduler
755	ssm	__LC_PGM_NEW_PSW	# disable I/O and ext. interrupts
756	TRACE_IRQS_OFF
757	j	.Lio_return
758
759#
760# _TIF_PATCH_PENDING is set, call klp_update_patch_state
761#
762#ifdef CONFIG_LIVEPATCH
763.Lio_patch_pending:
764	lg	%r2,__LC_CURRENT	# pass pointer to task struct
765	larl	%r14,.Lio_return
766	jg	klp_update_patch_state
767#endif
768
769#
770# _TIF_SIGPENDING or is set, call do_signal
771#
772.Lio_sigpending:
773	# TRACE_IRQS_ON already done at .Lio_return
774	ssm	__LC_SVC_NEW_PSW	# reenable interrupts
775	lgr	%r2,%r11		# pass pointer to pt_regs
776	brasl	%r14,do_signal
777	ssm	__LC_PGM_NEW_PSW	# disable I/O and ext. interrupts
778	TRACE_IRQS_OFF
779	j	.Lio_return
780
781#
782# _TIF_NOTIFY_RESUME or is set, call do_notify_resume
783#
784.Lio_notify_resume:
785	# TRACE_IRQS_ON already done at .Lio_return
786	ssm	__LC_SVC_NEW_PSW	# reenable interrupts
787	lgr	%r2,%r11		# pass pointer to pt_regs
788	brasl	%r14,do_notify_resume
789	ssm	__LC_PGM_NEW_PSW	# disable I/O and ext. interrupts
790	TRACE_IRQS_OFF
791	j	.Lio_return
792
793/*
794 * External interrupt handler routine
795 */
796ENTRY(ext_int_handler)
797	STCK	__LC_INT_CLOCK
798	stpt	__LC_ASYNC_ENTER_TIMER
799	stmg	%r8,%r15,__LC_SAVE_AREA_ASYNC
800	lg	%r12,__LC_CURRENT
801	larl	%r13,cleanup_critical
802	lmg	%r8,%r9,__LC_EXT_OLD_PSW
803	SWITCH_ASYNC __LC_SAVE_AREA_ASYNC,__LC_ASYNC_ENTER_TIMER
804	stmg	%r0,%r7,__PT_R0(%r11)
805	mvc	__PT_R8(64,%r11),__LC_SAVE_AREA_ASYNC
806	stmg	%r8,%r9,__PT_PSW(%r11)
807	lghi	%r1,__LC_EXT_PARAMS2
808	mvc	__PT_INT_CODE(4,%r11),__LC_EXT_CPU_ADDR
809	mvc	__PT_INT_PARM(4,%r11),__LC_EXT_PARAMS
810	mvc	__PT_INT_PARM_LONG(8,%r11),0(%r1)
811	xc	__PT_FLAGS(8,%r11),__PT_FLAGS(%r11)
812	TSTMSK	__LC_CPU_FLAGS,_CIF_IGNORE_IRQ
813	jo	.Lio_restore
814	TRACE_IRQS_OFF
815	xc	__SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
816	lgr	%r2,%r11		# pass pointer to pt_regs
817	lghi	%r3,EXT_INTERRUPT
818	brasl	%r14,do_IRQ
819	j	.Lio_return
820
821/*
822 * Load idle PSW. The second "half" of this function is in .Lcleanup_idle.
823 */
824ENTRY(psw_idle)
825	stg	%r3,__SF_EMPTY(%r15)
826	larl	%r1,.Lpsw_idle_lpsw+4
827	stg	%r1,__SF_EMPTY+8(%r15)
828#ifdef CONFIG_SMP
829	larl	%r1,smp_cpu_mtid
830	llgf	%r1,0(%r1)
831	ltgr	%r1,%r1
832	jz	.Lpsw_idle_stcctm
833	.insn	rsy,0xeb0000000017,%r1,5,__SF_EMPTY+16(%r15)
834.Lpsw_idle_stcctm:
835#endif
836	oi	__LC_CPU_FLAGS+7,_CIF_ENABLED_WAIT
837	STCK	__CLOCK_IDLE_ENTER(%r2)
838	stpt	__TIMER_IDLE_ENTER(%r2)
839.Lpsw_idle_lpsw:
840	lpswe	__SF_EMPTY(%r15)
841	br	%r14
842.Lpsw_idle_end:
843
844/*
845 * Store floating-point controls and floating-point or vector register
846 * depending whether the vector facility is available.	A critical section
847 * cleanup assures that the registers are stored even if interrupted for
848 * some other work.  The CIF_FPU flag is set to trigger a lazy restore
849 * of the register contents at return from io or a system call.
850 */
851ENTRY(save_fpu_regs)
852	lg	%r2,__LC_CURRENT
853	aghi	%r2,__TASK_thread
854	TSTMSK	__LC_CPU_FLAGS,_CIF_FPU
855	bor	%r14
856	stfpc	__THREAD_FPU_fpc(%r2)
857	lg	%r3,__THREAD_FPU_regs(%r2)
858	TSTMSK	__LC_MACHINE_FLAGS,MACHINE_FLAG_VX
859	jz	.Lsave_fpu_regs_fp	  # no -> store FP regs
860	VSTM	%v0,%v15,0,%r3		  # vstm 0,15,0(3)
861	VSTM	%v16,%v31,256,%r3	  # vstm 16,31,256(3)
862	j	.Lsave_fpu_regs_done	  # -> set CIF_FPU flag
863.Lsave_fpu_regs_fp:
864	std	0,0(%r3)
865	std	1,8(%r3)
866	std	2,16(%r3)
867	std	3,24(%r3)
868	std	4,32(%r3)
869	std	5,40(%r3)
870	std	6,48(%r3)
871	std	7,56(%r3)
872	std	8,64(%r3)
873	std	9,72(%r3)
874	std	10,80(%r3)
875	std	11,88(%r3)
876	std	12,96(%r3)
877	std	13,104(%r3)
878	std	14,112(%r3)
879	std	15,120(%r3)
880.Lsave_fpu_regs_done:
881	oi	__LC_CPU_FLAGS+7,_CIF_FPU
882	br	%r14
883.Lsave_fpu_regs_end:
884#if IS_ENABLED(CONFIG_KVM)
885EXPORT_SYMBOL(save_fpu_regs)
886#endif
887
888/*
889 * Load floating-point controls and floating-point or vector registers.
890 * A critical section cleanup assures that the register contents are
891 * loaded even if interrupted for some other work.
892 *
893 * There are special calling conventions to fit into sysc and io return work:
894 *	%r15:	<kernel stack>
895 * The function requires:
896 *	%r4
897 */
898load_fpu_regs:
899	lg	%r4,__LC_CURRENT
900	aghi	%r4,__TASK_thread
901	TSTMSK	__LC_CPU_FLAGS,_CIF_FPU
902	bnor	%r14
903	lfpc	__THREAD_FPU_fpc(%r4)
904	TSTMSK	__LC_MACHINE_FLAGS,MACHINE_FLAG_VX
905	lg	%r4,__THREAD_FPU_regs(%r4)	# %r4 <- reg save area
906	jz	.Lload_fpu_regs_fp		# -> no VX, load FP regs
907	VLM	%v0,%v15,0,%r4
908	VLM	%v16,%v31,256,%r4
909	j	.Lload_fpu_regs_done
910.Lload_fpu_regs_fp:
911	ld	0,0(%r4)
912	ld	1,8(%r4)
913	ld	2,16(%r4)
914	ld	3,24(%r4)
915	ld	4,32(%r4)
916	ld	5,40(%r4)
917	ld	6,48(%r4)
918	ld	7,56(%r4)
919	ld	8,64(%r4)
920	ld	9,72(%r4)
921	ld	10,80(%r4)
922	ld	11,88(%r4)
923	ld	12,96(%r4)
924	ld	13,104(%r4)
925	ld	14,112(%r4)
926	ld	15,120(%r4)
927.Lload_fpu_regs_done:
928	ni	__LC_CPU_FLAGS+7,255-_CIF_FPU
929	br	%r14
930.Lload_fpu_regs_end:
931
932.L__critical_end:
933
934/*
935 * Machine check handler routines
936 */
937ENTRY(mcck_int_handler)
938	STCK	__LC_MCCK_CLOCK
939	la	%r1,4095		# revalidate r1
940	spt	__LC_CPU_TIMER_SAVE_AREA-4095(%r1)	# revalidate cpu timer
941	lmg	%r0,%r15,__LC_GPREGS_SAVE_AREA-4095(%r1)# revalidate gprs
942	lg	%r12,__LC_CURRENT
943	larl	%r13,cleanup_critical
944	lmg	%r8,%r9,__LC_MCK_OLD_PSW
945	TSTMSK	__LC_MCCK_CODE,MCCK_CODE_SYSTEM_DAMAGE
946	jo	.Lmcck_panic		# yes -> rest of mcck code invalid
947	lghi	%r14,__LC_CPU_TIMER_SAVE_AREA
948	mvc	__LC_MCCK_ENTER_TIMER(8),0(%r14)
949	TSTMSK	__LC_MCCK_CODE,MCCK_CODE_CPU_TIMER_VALID
950	jo	3f
951	la	%r14,__LC_SYNC_ENTER_TIMER
952	clc	0(8,%r14),__LC_ASYNC_ENTER_TIMER
953	jl	0f
954	la	%r14,__LC_ASYNC_ENTER_TIMER
9550:	clc	0(8,%r14),__LC_EXIT_TIMER
956	jl	1f
957	la	%r14,__LC_EXIT_TIMER
9581:	clc	0(8,%r14),__LC_LAST_UPDATE_TIMER
959	jl	2f
960	la	%r14,__LC_LAST_UPDATE_TIMER
9612:	spt	0(%r14)
962	mvc	__LC_MCCK_ENTER_TIMER(8),0(%r14)
9633:	TSTMSK	__LC_MCCK_CODE,(MCCK_CODE_PSW_MWP_VALID|MCCK_CODE_PSW_IA_VALID)
964	jno	.Lmcck_panic		# no -> skip cleanup critical
965	SWITCH_ASYNC __LC_GPREGS_SAVE_AREA+64,__LC_MCCK_ENTER_TIMER
966.Lmcck_skip:
967	lghi	%r14,__LC_GPREGS_SAVE_AREA+64
968	stmg	%r0,%r7,__PT_R0(%r11)
969	mvc	__PT_R8(64,%r11),0(%r14)
970	stmg	%r8,%r9,__PT_PSW(%r11)
971	xc	__PT_FLAGS(8,%r11),__PT_FLAGS(%r11)
972	xc	__SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
973	lgr	%r2,%r11		# pass pointer to pt_regs
974	brasl	%r14,s390_do_machine_check
975	tm	__PT_PSW+1(%r11),0x01	# returning to user ?
976	jno	.Lmcck_return
977	lg	%r1,__LC_KERNEL_STACK	# switch to kernel stack
978	mvc	STACK_FRAME_OVERHEAD(__PT_SIZE,%r1),0(%r11)
979	xc	__SF_BACKCHAIN(8,%r1),__SF_BACKCHAIN(%r1)
980	la	%r11,STACK_FRAME_OVERHEAD(%r1)
981	lgr	%r15,%r1
982	ssm	__LC_PGM_NEW_PSW	# turn dat on, keep irqs off
983	TSTMSK	__LC_CPU_FLAGS,_CIF_MCCK_PENDING
984	jno	.Lmcck_return
985	TRACE_IRQS_OFF
986	brasl	%r14,s390_handle_mcck
987	TRACE_IRQS_ON
988.Lmcck_return:
989	lg	%r14,__LC_VDSO_PER_CPU
990	lmg	%r0,%r10,__PT_R0(%r11)
991	mvc	__LC_RETURN_MCCK_PSW(16),__PT_PSW(%r11) # move return PSW
992	tm	__LC_RETURN_MCCK_PSW+1,0x01 # returning to user ?
993	jno	0f
994	stpt	__LC_EXIT_TIMER
995	mvc	__VDSO_ECTG_BASE(16,%r14),__LC_EXIT_TIMER
9960:	lmg	%r11,%r15,__PT_R11(%r11)
997	lpswe	__LC_RETURN_MCCK_PSW
998
999.Lmcck_panic:
1000	lg	%r15,__LC_PANIC_STACK
1001	la	%r11,STACK_FRAME_OVERHEAD(%r15)
1002	j	.Lmcck_skip
1003
1004#
1005# PSW restart interrupt handler
1006#
1007ENTRY(restart_int_handler)
1008	TSTMSK	__LC_MACHINE_FLAGS,MACHINE_FLAG_LPP
1009	jz	0f
1010	.insn	s,0xb2800000,__LC_LPP
10110:	stg	%r15,__LC_SAVE_AREA_RESTART
1012	lg	%r15,__LC_RESTART_STACK
1013	aghi	%r15,-__PT_SIZE			# create pt_regs on stack
1014	xc	0(__PT_SIZE,%r15),0(%r15)
1015	stmg	%r0,%r14,__PT_R0(%r15)
1016	mvc	__PT_R15(8,%r15),__LC_SAVE_AREA_RESTART
1017	mvc	__PT_PSW(16,%r15),__LC_RST_OLD_PSW # store restart old psw
1018	aghi	%r15,-STACK_FRAME_OVERHEAD	# create stack frame on stack
1019	xc	0(STACK_FRAME_OVERHEAD,%r15),0(%r15)
1020	lg	%r1,__LC_RESTART_FN		# load fn, parm & source cpu
1021	lg	%r2,__LC_RESTART_DATA
1022	lg	%r3,__LC_RESTART_SOURCE
1023	ltgr	%r3,%r3				# test source cpu address
1024	jm	1f				# negative -> skip source stop
10250:	sigp	%r4,%r3,SIGP_SENSE		# sigp sense to source cpu
1026	brc	10,0b				# wait for status stored
10271:	basr	%r14,%r1			# call function
1028	stap	__SF_EMPTY(%r15)		# store cpu address
1029	llgh	%r3,__SF_EMPTY(%r15)
10302:	sigp	%r4,%r3,SIGP_STOP		# sigp stop to current cpu
1031	brc	2,2b
10323:	j	3b
1033
1034	.section .kprobes.text, "ax"
1035
1036#ifdef CONFIG_CHECK_STACK
1037/*
1038 * The synchronous or the asynchronous stack overflowed. We are dead.
1039 * No need to properly save the registers, we are going to panic anyway.
1040 * Setup a pt_regs so that show_trace can provide a good call trace.
1041 */
1042stack_overflow:
1043	lg	%r15,__LC_PANIC_STACK	# change to panic stack
1044	la	%r11,STACK_FRAME_OVERHEAD(%r15)
1045	stmg	%r0,%r7,__PT_R0(%r11)
1046	stmg	%r8,%r9,__PT_PSW(%r11)
1047	mvc	__PT_R8(64,%r11),0(%r14)
1048	stg	%r10,__PT_ORIG_GPR2(%r11) # store last break to orig_gpr2
1049	xc	__SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
1050	lgr	%r2,%r11		# pass pointer to pt_regs
1051	jg	kernel_stack_overflow
1052#endif
1053
1054cleanup_critical:
1055#if IS_ENABLED(CONFIG_KVM)
1056	clg	%r9,BASED(.Lcleanup_table_sie)	# .Lsie_gmap
1057	jl	0f
1058	clg	%r9,BASED(.Lcleanup_table_sie+8)# .Lsie_done
1059	jl	.Lcleanup_sie
1060#endif
1061	clg	%r9,BASED(.Lcleanup_table)	# system_call
1062	jl	0f
1063	clg	%r9,BASED(.Lcleanup_table+8)	# .Lsysc_do_svc
1064	jl	.Lcleanup_system_call
1065	clg	%r9,BASED(.Lcleanup_table+16)	# .Lsysc_tif
1066	jl	0f
1067	clg	%r9,BASED(.Lcleanup_table+24)	# .Lsysc_restore
1068	jl	.Lcleanup_sysc_tif
1069	clg	%r9,BASED(.Lcleanup_table+32)	# .Lsysc_done
1070	jl	.Lcleanup_sysc_restore
1071	clg	%r9,BASED(.Lcleanup_table+40)	# .Lio_tif
1072	jl	0f
1073	clg	%r9,BASED(.Lcleanup_table+48)	# .Lio_restore
1074	jl	.Lcleanup_io_tif
1075	clg	%r9,BASED(.Lcleanup_table+56)	# .Lio_done
1076	jl	.Lcleanup_io_restore
1077	clg	%r9,BASED(.Lcleanup_table+64)	# psw_idle
1078	jl	0f
1079	clg	%r9,BASED(.Lcleanup_table+72)	# .Lpsw_idle_end
1080	jl	.Lcleanup_idle
1081	clg	%r9,BASED(.Lcleanup_table+80)	# save_fpu_regs
1082	jl	0f
1083	clg	%r9,BASED(.Lcleanup_table+88)	# .Lsave_fpu_regs_end
1084	jl	.Lcleanup_save_fpu_regs
1085	clg	%r9,BASED(.Lcleanup_table+96)	# load_fpu_regs
1086	jl	0f
1087	clg	%r9,BASED(.Lcleanup_table+104)	# .Lload_fpu_regs_end
1088	jl	.Lcleanup_load_fpu_regs
10890:	br	%r14
1090
1091	.align	8
1092.Lcleanup_table:
1093	.quad	system_call
1094	.quad	.Lsysc_do_svc
1095	.quad	.Lsysc_tif
1096	.quad	.Lsysc_restore
1097	.quad	.Lsysc_done
1098	.quad	.Lio_tif
1099	.quad	.Lio_restore
1100	.quad	.Lio_done
1101	.quad	psw_idle
1102	.quad	.Lpsw_idle_end
1103	.quad	save_fpu_regs
1104	.quad	.Lsave_fpu_regs_end
1105	.quad	load_fpu_regs
1106	.quad	.Lload_fpu_regs_end
1107
1108#if IS_ENABLED(CONFIG_KVM)
1109.Lcleanup_table_sie:
1110	.quad	.Lsie_gmap
1111	.quad	.Lsie_done
1112
1113.Lcleanup_sie:
1114	lg	%r9,__SF_EMPTY(%r15)		# get control block pointer
1115	ni	__SIE_PROG0C+3(%r9),0xfe	# no longer in SIE
1116	lctlg	%c1,%c1,__LC_USER_ASCE		# load primary asce
1117	larl	%r9,sie_exit			# skip forward to sie_exit
1118	br	%r14
1119#endif
1120
1121.Lcleanup_system_call:
1122	# check if stpt has been executed
1123	clg	%r9,BASED(.Lcleanup_system_call_insn)
1124	jh	0f
1125	mvc	__LC_SYNC_ENTER_TIMER(8),__LC_ASYNC_ENTER_TIMER
1126	cghi	%r11,__LC_SAVE_AREA_ASYNC
1127	je	0f
1128	mvc	__LC_SYNC_ENTER_TIMER(8),__LC_MCCK_ENTER_TIMER
11290:	# check if stmg has been executed
1130	clg	%r9,BASED(.Lcleanup_system_call_insn+8)
1131	jh	0f
1132	mvc	__LC_SAVE_AREA_SYNC(64),0(%r11)
11330:	# check if base register setup + TIF bit load has been done
1134	clg	%r9,BASED(.Lcleanup_system_call_insn+16)
1135	jhe	0f
1136	# set up saved register r12 task struct pointer
1137	stg	%r12,32(%r11)
1138	# set up saved register r13 __TASK_thread offset
1139	mvc	40(8,%r11),BASED(.Lcleanup_system_call_const)
11400:	# check if the user time update has been done
1141	clg	%r9,BASED(.Lcleanup_system_call_insn+24)
1142	jh	0f
1143	lg	%r15,__LC_EXIT_TIMER
1144	slg	%r15,__LC_SYNC_ENTER_TIMER
1145	alg	%r15,__LC_USER_TIMER
1146	stg	%r15,__LC_USER_TIMER
11470:	# check if the system time update has been done
1148	clg	%r9,BASED(.Lcleanup_system_call_insn+32)
1149	jh	0f
1150	lg	%r15,__LC_LAST_UPDATE_TIMER
1151	slg	%r15,__LC_EXIT_TIMER
1152	alg	%r15,__LC_SYSTEM_TIMER
1153	stg	%r15,__LC_SYSTEM_TIMER
11540:	# update accounting time stamp
1155	mvc	__LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
1156	# set up saved register r11
1157	lg	%r15,__LC_KERNEL_STACK
1158	la	%r9,STACK_FRAME_OVERHEAD(%r15)
1159	stg	%r9,24(%r11)		# r11 pt_regs pointer
1160	# fill pt_regs
1161	mvc	__PT_R8(64,%r9),__LC_SAVE_AREA_SYNC
1162	stmg	%r0,%r7,__PT_R0(%r9)
1163	mvc	__PT_PSW(16,%r9),__LC_SVC_OLD_PSW
1164	mvc	__PT_INT_CODE(4,%r9),__LC_SVC_ILC
1165	xc	__PT_FLAGS(8,%r9),__PT_FLAGS(%r9)
1166	mvi	__PT_FLAGS+7(%r9),_PIF_SYSCALL
1167	# setup saved register r15
1168	stg	%r15,56(%r11)		# r15 stack pointer
1169	# set new psw address and exit
1170	larl	%r9,.Lsysc_do_svc
1171	br	%r14
1172.Lcleanup_system_call_insn:
1173	.quad	system_call
1174	.quad	.Lsysc_stmg
1175	.quad	.Lsysc_per
1176	.quad	.Lsysc_vtime+36
1177	.quad	.Lsysc_vtime+42
1178.Lcleanup_system_call_const:
1179	.quad	__TASK_thread
1180
1181.Lcleanup_sysc_tif:
1182	larl	%r9,.Lsysc_tif
1183	br	%r14
1184
1185.Lcleanup_sysc_restore:
1186	# check if stpt has been executed
1187	clg	%r9,BASED(.Lcleanup_sysc_restore_insn)
1188	jh	0f
1189	mvc	__LC_EXIT_TIMER(8),__LC_ASYNC_ENTER_TIMER
1190	cghi	%r11,__LC_SAVE_AREA_ASYNC
1191	je	0f
1192	mvc	__LC_EXIT_TIMER(8),__LC_MCCK_ENTER_TIMER
11930:	clg	%r9,BASED(.Lcleanup_sysc_restore_insn+8)
1194	je	1f
1195	lg	%r9,24(%r11)		# get saved pointer to pt_regs
1196	mvc	__LC_RETURN_PSW(16),__PT_PSW(%r9)
1197	mvc	0(64,%r11),__PT_R8(%r9)
1198	lmg	%r0,%r7,__PT_R0(%r9)
11991:	lmg	%r8,%r9,__LC_RETURN_PSW
1200	br	%r14
1201.Lcleanup_sysc_restore_insn:
1202	.quad	.Lsysc_exit_timer
1203	.quad	.Lsysc_done - 4
1204
1205.Lcleanup_io_tif:
1206	larl	%r9,.Lio_tif
1207	br	%r14
1208
1209.Lcleanup_io_restore:
1210	# check if stpt has been executed
1211	clg	%r9,BASED(.Lcleanup_io_restore_insn)
1212	jh	0f
1213	mvc	__LC_EXIT_TIMER(8),__LC_MCCK_ENTER_TIMER
12140:	clg	%r9,BASED(.Lcleanup_io_restore_insn+8)
1215	je	1f
1216	lg	%r9,24(%r11)		# get saved r11 pointer to pt_regs
1217	mvc	__LC_RETURN_PSW(16),__PT_PSW(%r9)
1218	mvc	0(64,%r11),__PT_R8(%r9)
1219	lmg	%r0,%r7,__PT_R0(%r9)
12201:	lmg	%r8,%r9,__LC_RETURN_PSW
1221	br	%r14
1222.Lcleanup_io_restore_insn:
1223	.quad	.Lio_exit_timer
1224	.quad	.Lio_done - 4
1225
1226.Lcleanup_idle:
1227	ni	__LC_CPU_FLAGS+7,255-_CIF_ENABLED_WAIT
1228	# copy interrupt clock & cpu timer
1229	mvc	__CLOCK_IDLE_EXIT(8,%r2),__LC_INT_CLOCK
1230	mvc	__TIMER_IDLE_EXIT(8,%r2),__LC_ASYNC_ENTER_TIMER
1231	cghi	%r11,__LC_SAVE_AREA_ASYNC
1232	je	0f
1233	mvc	__CLOCK_IDLE_EXIT(8,%r2),__LC_MCCK_CLOCK
1234	mvc	__TIMER_IDLE_EXIT(8,%r2),__LC_MCCK_ENTER_TIMER
12350:	# check if stck & stpt have been executed
1236	clg	%r9,BASED(.Lcleanup_idle_insn)
1237	jhe	1f
1238	mvc	__CLOCK_IDLE_ENTER(8,%r2),__CLOCK_IDLE_EXIT(%r2)
1239	mvc	__TIMER_IDLE_ENTER(8,%r2),__TIMER_IDLE_EXIT(%r2)
12401:	# calculate idle cycles
1241#ifdef CONFIG_SMP
1242	clg	%r9,BASED(.Lcleanup_idle_insn)
1243	jl	3f
1244	larl	%r1,smp_cpu_mtid
1245	llgf	%r1,0(%r1)
1246	ltgr	%r1,%r1
1247	jz	3f
1248	.insn	rsy,0xeb0000000017,%r1,5,__SF_EMPTY+80(%r15)
1249	larl	%r3,mt_cycles
1250	ag	%r3,__LC_PERCPU_OFFSET
1251	la	%r4,__SF_EMPTY+16(%r15)
12522:	lg	%r0,0(%r3)
1253	slg	%r0,0(%r4)
1254	alg	%r0,64(%r4)
1255	stg	%r0,0(%r3)
1256	la	%r3,8(%r3)
1257	la	%r4,8(%r4)
1258	brct	%r1,2b
1259#endif
12603:	# account system time going idle
1261	lg	%r9,__LC_STEAL_TIMER
1262	alg	%r9,__CLOCK_IDLE_ENTER(%r2)
1263	slg	%r9,__LC_LAST_UPDATE_CLOCK
1264	stg	%r9,__LC_STEAL_TIMER
1265	mvc	__LC_LAST_UPDATE_CLOCK(8),__CLOCK_IDLE_EXIT(%r2)
1266	lg	%r9,__LC_SYSTEM_TIMER
1267	alg	%r9,__LC_LAST_UPDATE_TIMER
1268	slg	%r9,__TIMER_IDLE_ENTER(%r2)
1269	stg	%r9,__LC_SYSTEM_TIMER
1270	mvc	__LC_LAST_UPDATE_TIMER(8),__TIMER_IDLE_EXIT(%r2)
1271	# prepare return psw
1272	nihh	%r8,0xfcfd		# clear irq & wait state bits
1273	lg	%r9,48(%r11)		# return from psw_idle
1274	br	%r14
1275.Lcleanup_idle_insn:
1276	.quad	.Lpsw_idle_lpsw
1277
1278.Lcleanup_save_fpu_regs:
1279	larl	%r9,save_fpu_regs
1280	br	%r14
1281
1282.Lcleanup_load_fpu_regs:
1283	larl	%r9,load_fpu_regs
1284	br	%r14
1285
1286/*
1287 * Integer constants
1288 */
1289	.align	8
1290.Lcritical_start:
1291	.quad	.L__critical_start
1292.Lcritical_length:
1293	.quad	.L__critical_end - .L__critical_start
1294#if IS_ENABLED(CONFIG_KVM)
1295.Lsie_critical_start:
1296	.quad	.Lsie_gmap
1297.Lsie_critical_length:
1298	.quad	.Lsie_done - .Lsie_gmap
1299#endif
1300
1301	.section .rodata, "a"
1302#define SYSCALL(esame,emu)	.long esame
1303	.globl	sys_call_table
1304sys_call_table:
1305#include "syscalls.S"
1306#undef SYSCALL
1307
1308#ifdef CONFIG_COMPAT
1309
1310#define SYSCALL(esame,emu)	.long emu
1311	.globl	sys_call_table_emu
1312sys_call_table_emu:
1313#include "syscalls.S"
1314#undef SYSCALL
1315#endif
1316