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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * S390 version
4 * Copyright IBM Corp. 1999, 2000
5 * Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
6 * Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com),
7 *
8 * Derived from "arch/i386/kernel/traps.c"
9 * Copyright (C) 1991, 1992 Linus Torvalds
10 */
11
12/*
13 * 'Traps.c' handles hardware traps and faults after we have saved some
14 * state in 'asm.s'.
15 */
16#include "asm/irqflags.h"
17#include "asm/ptrace.h"
18#include <linux/kprobes.h>
19#include <linux/kdebug.h>
20#include <linux/randomize_kstack.h>
21#include <linux/extable.h>
22#include <linux/ptrace.h>
23#include <linux/sched.h>
24#include <linux/sched/debug.h>
25#include <linux/mm.h>
26#include <linux/slab.h>
27#include <linux/uaccess.h>
28#include <linux/cpu.h>
29#include <linux/entry-common.h>
30#include <linux/kmsan.h>
31#include <asm/asm-extable.h>
32#include <asm/vtime.h>
33#include <asm/fpu.h>
34#include <asm/fault.h>
35#include "entry.h"
36
37static inline void __user *get_trap_ip(struct pt_regs *regs)
38{
39 unsigned long address;
40
41 if (regs->int_code & 0x200)
42 address = current->thread.trap_tdb.data[3];
43 else
44 address = regs->psw.addr;
45 return (void __user *) (address - (regs->int_code >> 16));
46}
47
48#ifdef CONFIG_GENERIC_BUG
49int is_valid_bugaddr(unsigned long addr)
50{
51 return 1;
52}
53#endif
54
55void do_report_trap(struct pt_regs *regs, int si_signo, int si_code, char *str)
56{
57 if (user_mode(regs)) {
58 force_sig_fault(si_signo, si_code, get_trap_ip(regs));
59 report_user_fault(regs, si_signo, 0);
60 } else {
61 if (!fixup_exception(regs))
62 die(regs, str);
63 }
64}
65
66static void do_trap(struct pt_regs *regs, int si_signo, int si_code, char *str)
67{
68 if (notify_die(DIE_TRAP, str, regs, 0,
69 regs->int_code, si_signo) == NOTIFY_STOP)
70 return;
71 do_report_trap(regs, si_signo, si_code, str);
72}
73NOKPROBE_SYMBOL(do_trap);
74
75void do_per_trap(struct pt_regs *regs)
76{
77 if (notify_die(DIE_SSTEP, "sstep", regs, 0, 0, SIGTRAP) == NOTIFY_STOP)
78 return;
79 if (!current->ptrace)
80 return;
81 force_sig_fault(SIGTRAP, TRAP_HWBKPT,
82 (void __force __user *) current->thread.per_event.address);
83}
84NOKPROBE_SYMBOL(do_per_trap);
85
86static void default_trap_handler(struct pt_regs *regs)
87{
88 if (user_mode(regs)) {
89 report_user_fault(regs, SIGSEGV, 0);
90 force_exit_sig(SIGSEGV);
91 } else
92 die(regs, "Unknown program exception");
93}
94
95#define DO_ERROR_INFO(name, signr, sicode, str) \
96static void name(struct pt_regs *regs) \
97{ \
98 do_trap(regs, signr, sicode, str); \
99}
100
101DO_ERROR_INFO(addressing_exception, SIGILL, ILL_ILLADR,
102 "addressing exception")
103DO_ERROR_INFO(execute_exception, SIGILL, ILL_ILLOPN,
104 "execute exception")
105DO_ERROR_INFO(divide_exception, SIGFPE, FPE_INTDIV,
106 "fixpoint divide exception")
107DO_ERROR_INFO(overflow_exception, SIGFPE, FPE_INTOVF,
108 "fixpoint overflow exception")
109DO_ERROR_INFO(hfp_overflow_exception, SIGFPE, FPE_FLTOVF,
110 "HFP overflow exception")
111DO_ERROR_INFO(hfp_underflow_exception, SIGFPE, FPE_FLTUND,
112 "HFP underflow exception")
113DO_ERROR_INFO(hfp_significance_exception, SIGFPE, FPE_FLTRES,
114 "HFP significance exception")
115DO_ERROR_INFO(hfp_divide_exception, SIGFPE, FPE_FLTDIV,
116 "HFP divide exception")
117DO_ERROR_INFO(hfp_sqrt_exception, SIGFPE, FPE_FLTINV,
118 "HFP square root exception")
119DO_ERROR_INFO(operand_exception, SIGILL, ILL_ILLOPN,
120 "operand exception")
121DO_ERROR_INFO(privileged_op, SIGILL, ILL_PRVOPC,
122 "privileged operation")
123DO_ERROR_INFO(special_op_exception, SIGILL, ILL_ILLOPN,
124 "special operation exception")
125DO_ERROR_INFO(transaction_exception, SIGILL, ILL_ILLOPN,
126 "transaction constraint exception")
127
128static inline void do_fp_trap(struct pt_regs *regs, __u32 fpc)
129{
130 int si_code = 0;
131 /* FPC[2] is Data Exception Code */
132 if ((fpc & 0x00000300) == 0) {
133 /* bits 6 and 7 of DXC are 0 iff IEEE exception */
134 if (fpc & 0x8000) /* invalid fp operation */
135 si_code = FPE_FLTINV;
136 else if (fpc & 0x4000) /* div by 0 */
137 si_code = FPE_FLTDIV;
138 else if (fpc & 0x2000) /* overflow */
139 si_code = FPE_FLTOVF;
140 else if (fpc & 0x1000) /* underflow */
141 si_code = FPE_FLTUND;
142 else if (fpc & 0x0800) /* inexact */
143 si_code = FPE_FLTRES;
144 }
145 do_trap(regs, SIGFPE, si_code, "floating point exception");
146}
147
148static void translation_specification_exception(struct pt_regs *regs)
149{
150 /* May never happen. */
151 panic("Translation-Specification Exception");
152}
153
154static void illegal_op(struct pt_regs *regs)
155{
156 __u8 opcode[6];
157 __u16 __user *location;
158 int is_uprobe_insn = 0;
159 int signal = 0;
160
161 location = get_trap_ip(regs);
162
163 if (user_mode(regs)) {
164 if (get_user(*((__u16 *) opcode), (__u16 __user *) location))
165 return;
166 if (*((__u16 *) opcode) == S390_BREAKPOINT_U16) {
167 if (current->ptrace)
168 force_sig_fault(SIGTRAP, TRAP_BRKPT, location);
169 else
170 signal = SIGILL;
171#ifdef CONFIG_UPROBES
172 } else if (*((__u16 *) opcode) == UPROBE_SWBP_INSN) {
173 is_uprobe_insn = 1;
174#endif
175 } else
176 signal = SIGILL;
177 }
178 /*
179 * We got either an illegal op in kernel mode, or user space trapped
180 * on a uprobes illegal instruction. See if kprobes or uprobes picks
181 * it up. If not, SIGILL.
182 */
183 if (is_uprobe_insn || !user_mode(regs)) {
184 if (notify_die(DIE_BPT, "bpt", regs, 0,
185 3, SIGTRAP) != NOTIFY_STOP)
186 signal = SIGILL;
187 }
188 if (signal)
189 do_trap(regs, signal, ILL_ILLOPC, "illegal operation");
190}
191NOKPROBE_SYMBOL(illegal_op);
192
193DO_ERROR_INFO(specification_exception, SIGILL, ILL_ILLOPN,
194 "specification exception");
195
196static void vector_exception(struct pt_regs *regs)
197{
198 int si_code, vic;
199
200 if (!cpu_has_vx()) {
201 do_trap(regs, SIGILL, ILL_ILLOPN, "illegal operation");
202 return;
203 }
204
205 /* get vector interrupt code from fpc */
206 save_user_fpu_regs();
207 vic = (current->thread.ufpu.fpc & 0xf00) >> 8;
208 switch (vic) {
209 case 1: /* invalid vector operation */
210 si_code = FPE_FLTINV;
211 break;
212 case 2: /* division by zero */
213 si_code = FPE_FLTDIV;
214 break;
215 case 3: /* overflow */
216 si_code = FPE_FLTOVF;
217 break;
218 case 4: /* underflow */
219 si_code = FPE_FLTUND;
220 break;
221 case 5: /* inexact */
222 si_code = FPE_FLTRES;
223 break;
224 default: /* unknown cause */
225 si_code = 0;
226 }
227 do_trap(regs, SIGFPE, si_code, "vector exception");
228}
229
230static void data_exception(struct pt_regs *regs)
231{
232 save_user_fpu_regs();
233 if (current->thread.ufpu.fpc & FPC_DXC_MASK)
234 do_fp_trap(regs, current->thread.ufpu.fpc);
235 else
236 do_trap(regs, SIGILL, ILL_ILLOPN, "data exception");
237}
238
239static void space_switch_exception(struct pt_regs *regs)
240{
241 /* Set user psw back to home space mode. */
242 if (user_mode(regs))
243 regs->psw.mask |= PSW_ASC_HOME;
244 /* Send SIGILL. */
245 do_trap(regs, SIGILL, ILL_PRVOPC, "space switch event");
246}
247
248static void monitor_event_exception(struct pt_regs *regs)
249{
250 if (user_mode(regs))
251 return;
252
253 switch (report_bug(regs->psw.addr - (regs->int_code >> 16), regs)) {
254 case BUG_TRAP_TYPE_NONE:
255 fixup_exception(regs);
256 break;
257 case BUG_TRAP_TYPE_WARN:
258 break;
259 case BUG_TRAP_TYPE_BUG:
260 die(regs, "monitor event");
261 break;
262 }
263}
264
265void kernel_stack_overflow(struct pt_regs *regs)
266{
267 /*
268 * Normally regs are unpoisoned by the generic entry code, but
269 * kernel_stack_overflow() is a rare case that is called bypassing it.
270 */
271 kmsan_unpoison_entry_regs(regs);
272 bust_spinlocks(1);
273 printk("Kernel stack overflow.\n");
274 show_regs(regs);
275 bust_spinlocks(0);
276 panic("Corrupt kernel stack, can't continue.");
277}
278NOKPROBE_SYMBOL(kernel_stack_overflow);
279
280static void __init test_monitor_call(void)
281{
282 int val = 1;
283
284 if (!IS_ENABLED(CONFIG_BUG))
285 return;
286 asm volatile(
287 " mc 0,0\n"
288 "0: lhi %[val],0\n"
289 "1:\n"
290 EX_TABLE(0b, 1b)
291 : [val] "+d" (val));
292 if (!val)
293 panic("Monitor call doesn't work!\n");
294}
295
296void __init trap_init(void)
297{
298 struct lowcore *lc = get_lowcore();
299 unsigned long flags;
300 struct ctlreg cr0;
301
302 local_irq_save(flags);
303 cr0 = local_ctl_clear_bit(0, CR0_LOW_ADDRESS_PROTECTION_BIT);
304 psw_bits(lc->external_new_psw).mcheck = 1;
305 psw_bits(lc->program_new_psw).mcheck = 1;
306 psw_bits(lc->svc_new_psw).mcheck = 1;
307 psw_bits(lc->io_new_psw).mcheck = 1;
308 local_ctl_load(0, &cr0);
309 local_irq_restore(flags);
310 local_mcck_enable();
311 test_monitor_call();
312}
313
314static void (*pgm_check_table[128])(struct pt_regs *regs);
315
316void noinstr __do_pgm_check(struct pt_regs *regs)
317{
318 struct lowcore *lc = get_lowcore();
319 irqentry_state_t state;
320 unsigned int trapnr;
321 union teid teid;
322
323 teid.val = lc->trans_exc_code;
324 regs->int_code = lc->pgm_int_code;
325 regs->int_parm_long = teid.val;
326
327 /*
328 * In case of a guest fault, short-circuit the fault handler and return.
329 * This way the sie64a() function will return 0; fault address and
330 * other relevant bits are saved in current->thread.gmap_teid, and
331 * the fault number in current->thread.gmap_int_code. KVM will be
332 * able to use this information to handle the fault.
333 */
334 if (test_pt_regs_flag(regs, PIF_GUEST_FAULT)) {
335 current->thread.gmap_teid.val = regs->int_parm_long;
336 current->thread.gmap_int_code = regs->int_code & 0xffff;
337 return;
338 }
339
340 state = irqentry_enter(regs);
341
342 if (user_mode(regs)) {
343 update_timer_sys();
344 if (!static_branch_likely(&cpu_has_bear)) {
345 if (regs->last_break < 4096)
346 regs->last_break = 1;
347 }
348 current->thread.last_break = regs->last_break;
349 }
350
351 if (lc->pgm_code & 0x0200) {
352 /* transaction abort */
353 current->thread.trap_tdb = lc->pgm_tdb;
354 }
355
356 if (lc->pgm_code & PGM_INT_CODE_PER) {
357 if (user_mode(regs)) {
358 struct per_event *ev = ¤t->thread.per_event;
359
360 set_thread_flag(TIF_PER_TRAP);
361 ev->address = lc->per_address;
362 ev->cause = lc->per_code_combined;
363 ev->paid = lc->per_access_id;
364 } else {
365 /* PER event in kernel is kprobes */
366 __arch_local_irq_ssm(regs->psw.mask & ~PSW_MASK_PER);
367 do_per_trap(regs);
368 goto out;
369 }
370 }
371
372 if (!irqs_disabled_flags(regs->psw.mask))
373 trace_hardirqs_on();
374 __arch_local_irq_ssm(regs->psw.mask & ~PSW_MASK_PER);
375
376 trapnr = regs->int_code & PGM_INT_CODE_MASK;
377 if (trapnr)
378 pgm_check_table[trapnr](regs);
379out:
380 local_irq_disable();
381 irqentry_exit(regs, state);
382}
383
384/*
385 * The program check table contains exactly 128 (0x00-0x7f) entries. Each
386 * line defines the function to be called corresponding to the program check
387 * interruption code.
388 */
389static void (*pgm_check_table[128])(struct pt_regs *regs) = {
390 [0x00] = default_trap_handler,
391 [0x01] = illegal_op,
392 [0x02] = privileged_op,
393 [0x03] = execute_exception,
394 [0x04] = do_protection_exception,
395 [0x05] = addressing_exception,
396 [0x06] = specification_exception,
397 [0x07] = data_exception,
398 [0x08] = overflow_exception,
399 [0x09] = divide_exception,
400 [0x0a] = overflow_exception,
401 [0x0b] = divide_exception,
402 [0x0c] = hfp_overflow_exception,
403 [0x0d] = hfp_underflow_exception,
404 [0x0e] = hfp_significance_exception,
405 [0x0f] = hfp_divide_exception,
406 [0x10] = do_dat_exception,
407 [0x11] = do_dat_exception,
408 [0x12] = translation_specification_exception,
409 [0x13] = special_op_exception,
410 [0x14] = default_trap_handler,
411 [0x15] = operand_exception,
412 [0x16] = default_trap_handler,
413 [0x17] = default_trap_handler,
414 [0x18] = transaction_exception,
415 [0x19] = default_trap_handler,
416 [0x1a] = default_trap_handler,
417 [0x1b] = vector_exception,
418 [0x1c] = space_switch_exception,
419 [0x1d] = hfp_sqrt_exception,
420 [0x1e ... 0x37] = default_trap_handler,
421 [0x38] = do_dat_exception,
422 [0x39] = do_dat_exception,
423 [0x3a] = do_dat_exception,
424 [0x3b] = do_dat_exception,
425 [0x3c] = default_trap_handler,
426 [0x3d] = do_secure_storage_access,
427 [0x3e] = default_trap_handler,
428 [0x3f] = default_trap_handler,
429 [0x40] = monitor_event_exception,
430 [0x41 ... 0x7f] = default_trap_handler,
431};
432
433#define COND_TRAP(x) asm( \
434 ".weak " __stringify(x) "\n\t" \
435 ".set " __stringify(x) "," \
436 __stringify(default_trap_handler))
437
438COND_TRAP(do_secure_storage_access);
1/*
2 * S390 version
3 * Copyright IBM Corp. 1999, 2000
4 * Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
5 * Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com),
6 *
7 * Derived from "arch/i386/kernel/traps.c"
8 * Copyright (C) 1991, 1992 Linus Torvalds
9 */
10
11/*
12 * 'Traps.c' handles hardware traps and faults after we have saved some
13 * state in 'asm.s'.
14 */
15#include <linux/kprobes.h>
16#include <linux/kdebug.h>
17#include <linux/extable.h>
18#include <linux/ptrace.h>
19#include <linux/sched.h>
20#include <linux/mm.h>
21#include <linux/slab.h>
22#include <linux/uaccess.h>
23#include <asm/fpu/api.h>
24#include "entry.h"
25
26static inline void __user *get_trap_ip(struct pt_regs *regs)
27{
28 unsigned long address;
29
30 if (regs->int_code & 0x200)
31 address = *(unsigned long *)(current->thread.trap_tdb + 24);
32 else
33 address = regs->psw.addr;
34 return (void __user *) (address - (regs->int_code >> 16));
35}
36
37int is_valid_bugaddr(unsigned long addr)
38{
39 return 1;
40}
41
42void do_report_trap(struct pt_regs *regs, int si_signo, int si_code, char *str)
43{
44 siginfo_t info;
45
46 if (user_mode(regs)) {
47 info.si_signo = si_signo;
48 info.si_errno = 0;
49 info.si_code = si_code;
50 info.si_addr = get_trap_ip(regs);
51 force_sig_info(si_signo, &info, current);
52 report_user_fault(regs, si_signo, 0);
53 } else {
54 const struct exception_table_entry *fixup;
55 fixup = search_exception_tables(regs->psw.addr);
56 if (fixup)
57 regs->psw.addr = extable_fixup(fixup);
58 else {
59 enum bug_trap_type btt;
60
61 btt = report_bug(regs->psw.addr, regs);
62 if (btt == BUG_TRAP_TYPE_WARN)
63 return;
64 die(regs, str);
65 }
66 }
67}
68
69static void do_trap(struct pt_regs *regs, int si_signo, int si_code, char *str)
70{
71 if (notify_die(DIE_TRAP, str, regs, 0,
72 regs->int_code, si_signo) == NOTIFY_STOP)
73 return;
74 do_report_trap(regs, si_signo, si_code, str);
75}
76NOKPROBE_SYMBOL(do_trap);
77
78void do_per_trap(struct pt_regs *regs)
79{
80 siginfo_t info;
81
82 if (notify_die(DIE_SSTEP, "sstep", regs, 0, 0, SIGTRAP) == NOTIFY_STOP)
83 return;
84 if (!current->ptrace)
85 return;
86 info.si_signo = SIGTRAP;
87 info.si_errno = 0;
88 info.si_code = TRAP_HWBKPT;
89 info.si_addr =
90 (void __force __user *) current->thread.per_event.address;
91 force_sig_info(SIGTRAP, &info, current);
92}
93NOKPROBE_SYMBOL(do_per_trap);
94
95void default_trap_handler(struct pt_regs *regs)
96{
97 if (user_mode(regs)) {
98 report_user_fault(regs, SIGSEGV, 0);
99 do_exit(SIGSEGV);
100 } else
101 die(regs, "Unknown program exception");
102}
103
104#define DO_ERROR_INFO(name, signr, sicode, str) \
105void name(struct pt_regs *regs) \
106{ \
107 do_trap(regs, signr, sicode, str); \
108}
109
110DO_ERROR_INFO(addressing_exception, SIGILL, ILL_ILLADR,
111 "addressing exception")
112DO_ERROR_INFO(execute_exception, SIGILL, ILL_ILLOPN,
113 "execute exception")
114DO_ERROR_INFO(divide_exception, SIGFPE, FPE_INTDIV,
115 "fixpoint divide exception")
116DO_ERROR_INFO(overflow_exception, SIGFPE, FPE_INTOVF,
117 "fixpoint overflow exception")
118DO_ERROR_INFO(hfp_overflow_exception, SIGFPE, FPE_FLTOVF,
119 "HFP overflow exception")
120DO_ERROR_INFO(hfp_underflow_exception, SIGFPE, FPE_FLTUND,
121 "HFP underflow exception")
122DO_ERROR_INFO(hfp_significance_exception, SIGFPE, FPE_FLTRES,
123 "HFP significance exception")
124DO_ERROR_INFO(hfp_divide_exception, SIGFPE, FPE_FLTDIV,
125 "HFP divide exception")
126DO_ERROR_INFO(hfp_sqrt_exception, SIGFPE, FPE_FLTINV,
127 "HFP square root exception")
128DO_ERROR_INFO(operand_exception, SIGILL, ILL_ILLOPN,
129 "operand exception")
130DO_ERROR_INFO(privileged_op, SIGILL, ILL_PRVOPC,
131 "privileged operation")
132DO_ERROR_INFO(special_op_exception, SIGILL, ILL_ILLOPN,
133 "special operation exception")
134DO_ERROR_INFO(transaction_exception, SIGILL, ILL_ILLOPN,
135 "transaction constraint exception")
136
137static inline void do_fp_trap(struct pt_regs *regs, __u32 fpc)
138{
139 int si_code = 0;
140 /* FPC[2] is Data Exception Code */
141 if ((fpc & 0x00000300) == 0) {
142 /* bits 6 and 7 of DXC are 0 iff IEEE exception */
143 if (fpc & 0x8000) /* invalid fp operation */
144 si_code = FPE_FLTINV;
145 else if (fpc & 0x4000) /* div by 0 */
146 si_code = FPE_FLTDIV;
147 else if (fpc & 0x2000) /* overflow */
148 si_code = FPE_FLTOVF;
149 else if (fpc & 0x1000) /* underflow */
150 si_code = FPE_FLTUND;
151 else if (fpc & 0x0800) /* inexact */
152 si_code = FPE_FLTRES;
153 }
154 do_trap(regs, SIGFPE, si_code, "floating point exception");
155}
156
157void translation_exception(struct pt_regs *regs)
158{
159 /* May never happen. */
160 panic("Translation exception");
161}
162
163void illegal_op(struct pt_regs *regs)
164{
165 siginfo_t info;
166 __u8 opcode[6];
167 __u16 __user *location;
168 int is_uprobe_insn = 0;
169 int signal = 0;
170
171 location = get_trap_ip(regs);
172
173 if (user_mode(regs)) {
174 if (get_user(*((__u16 *) opcode), (__u16 __user *) location))
175 return;
176 if (*((__u16 *) opcode) == S390_BREAKPOINT_U16) {
177 if (current->ptrace) {
178 info.si_signo = SIGTRAP;
179 info.si_errno = 0;
180 info.si_code = TRAP_BRKPT;
181 info.si_addr = location;
182 force_sig_info(SIGTRAP, &info, current);
183 } else
184 signal = SIGILL;
185#ifdef CONFIG_UPROBES
186 } else if (*((__u16 *) opcode) == UPROBE_SWBP_INSN) {
187 is_uprobe_insn = 1;
188#endif
189 } else
190 signal = SIGILL;
191 }
192 /*
193 * We got either an illegal op in kernel mode, or user space trapped
194 * on a uprobes illegal instruction. See if kprobes or uprobes picks
195 * it up. If not, SIGILL.
196 */
197 if (is_uprobe_insn || !user_mode(regs)) {
198 if (notify_die(DIE_BPT, "bpt", regs, 0,
199 3, SIGTRAP) != NOTIFY_STOP)
200 signal = SIGILL;
201 }
202 if (signal)
203 do_trap(regs, signal, ILL_ILLOPC, "illegal operation");
204}
205NOKPROBE_SYMBOL(illegal_op);
206
207DO_ERROR_INFO(specification_exception, SIGILL, ILL_ILLOPN,
208 "specification exception");
209
210void vector_exception(struct pt_regs *regs)
211{
212 int si_code, vic;
213
214 if (!MACHINE_HAS_VX) {
215 do_trap(regs, SIGILL, ILL_ILLOPN, "illegal operation");
216 return;
217 }
218
219 /* get vector interrupt code from fpc */
220 save_fpu_regs();
221 vic = (current->thread.fpu.fpc & 0xf00) >> 8;
222 switch (vic) {
223 case 1: /* invalid vector operation */
224 si_code = FPE_FLTINV;
225 break;
226 case 2: /* division by zero */
227 si_code = FPE_FLTDIV;
228 break;
229 case 3: /* overflow */
230 si_code = FPE_FLTOVF;
231 break;
232 case 4: /* underflow */
233 si_code = FPE_FLTUND;
234 break;
235 case 5: /* inexact */
236 si_code = FPE_FLTRES;
237 break;
238 default: /* unknown cause */
239 si_code = 0;
240 }
241 do_trap(regs, SIGFPE, si_code, "vector exception");
242}
243
244void data_exception(struct pt_regs *regs)
245{
246 int signal = 0;
247
248 save_fpu_regs();
249 if (current->thread.fpu.fpc & FPC_DXC_MASK)
250 signal = SIGFPE;
251 else
252 signal = SIGILL;
253 if (signal == SIGFPE)
254 do_fp_trap(regs, current->thread.fpu.fpc);
255 else if (signal)
256 do_trap(regs, signal, ILL_ILLOPN, "data exception");
257}
258
259void space_switch_exception(struct pt_regs *regs)
260{
261 /* Set user psw back to home space mode. */
262 if (user_mode(regs))
263 regs->psw.mask |= PSW_ASC_HOME;
264 /* Send SIGILL. */
265 do_trap(regs, SIGILL, ILL_PRVOPC, "space switch event");
266}
267
268void kernel_stack_overflow(struct pt_regs *regs)
269{
270 bust_spinlocks(1);
271 printk("Kernel stack overflow.\n");
272 show_regs(regs);
273 bust_spinlocks(0);
274 panic("Corrupt kernel stack, can't continue.");
275}
276NOKPROBE_SYMBOL(kernel_stack_overflow);
277
278void __init trap_init(void)
279{
280 local_mcck_enable();
281}