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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}
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/module.h>
18#include <linux/ptrace.h>
19#include <linux/sched.h>
20#include <linux/mm.h>
21#include <linux/slab.h>
22#include <asm/fpu/api.h>
23#include "entry.h"
24
25static inline void __user *get_trap_ip(struct pt_regs *regs)
26{
27 unsigned long address;
28
29 if (regs->int_code & 0x200)
30 address = *(unsigned long *)(current->thread.trap_tdb + 24);
31 else
32 address = regs->psw.addr;
33 return (void __user *) (address - (regs->int_code >> 16));
34}
35
36int is_valid_bugaddr(unsigned long addr)
37{
38 return 1;
39}
40
41void do_report_trap(struct pt_regs *regs, int si_signo, int si_code, char *str)
42{
43 siginfo_t info;
44
45 if (user_mode(regs)) {
46 info.si_signo = si_signo;
47 info.si_errno = 0;
48 info.si_code = si_code;
49 info.si_addr = get_trap_ip(regs);
50 force_sig_info(si_signo, &info, current);
51 report_user_fault(regs, si_signo, 0);
52 } else {
53 const struct exception_table_entry *fixup;
54 fixup = search_exception_tables(regs->psw.addr);
55 if (fixup)
56 regs->psw.addr = extable_fixup(fixup);
57 else {
58 enum bug_trap_type btt;
59
60 btt = report_bug(regs->psw.addr, regs);
61 if (btt == BUG_TRAP_TYPE_WARN)
62 return;
63 die(regs, str);
64 }
65 }
66}
67
68static void do_trap(struct pt_regs *regs, int si_signo, int si_code, char *str)
69{
70 if (notify_die(DIE_TRAP, str, regs, 0,
71 regs->int_code, si_signo) == NOTIFY_STOP)
72 return;
73 do_report_trap(regs, si_signo, si_code, str);
74}
75NOKPROBE_SYMBOL(do_trap);
76
77void do_per_trap(struct pt_regs *regs)
78{
79 siginfo_t info;
80
81 if (notify_die(DIE_SSTEP, "sstep", regs, 0, 0, SIGTRAP) == NOTIFY_STOP)
82 return;
83 if (!current->ptrace)
84 return;
85 info.si_signo = SIGTRAP;
86 info.si_errno = 0;
87 info.si_code = TRAP_HWBKPT;
88 info.si_addr =
89 (void __force __user *) current->thread.per_event.address;
90 force_sig_info(SIGTRAP, &info, current);
91}
92NOKPROBE_SYMBOL(do_per_trap);
93
94void default_trap_handler(struct pt_regs *regs)
95{
96 if (user_mode(regs)) {
97 report_user_fault(regs, SIGSEGV, 0);
98 do_exit(SIGSEGV);
99 } else
100 die(regs, "Unknown program exception");
101}
102
103#define DO_ERROR_INFO(name, signr, sicode, str) \
104void name(struct pt_regs *regs) \
105{ \
106 do_trap(regs, signr, sicode, str); \
107}
108
109DO_ERROR_INFO(addressing_exception, SIGILL, ILL_ILLADR,
110 "addressing exception")
111DO_ERROR_INFO(execute_exception, SIGILL, ILL_ILLOPN,
112 "execute exception")
113DO_ERROR_INFO(divide_exception, SIGFPE, FPE_INTDIV,
114 "fixpoint divide exception")
115DO_ERROR_INFO(overflow_exception, SIGFPE, FPE_INTOVF,
116 "fixpoint overflow exception")
117DO_ERROR_INFO(hfp_overflow_exception, SIGFPE, FPE_FLTOVF,
118 "HFP overflow exception")
119DO_ERROR_INFO(hfp_underflow_exception, SIGFPE, FPE_FLTUND,
120 "HFP underflow exception")
121DO_ERROR_INFO(hfp_significance_exception, SIGFPE, FPE_FLTRES,
122 "HFP significance exception")
123DO_ERROR_INFO(hfp_divide_exception, SIGFPE, FPE_FLTDIV,
124 "HFP divide exception")
125DO_ERROR_INFO(hfp_sqrt_exception, SIGFPE, FPE_FLTINV,
126 "HFP square root exception")
127DO_ERROR_INFO(operand_exception, SIGILL, ILL_ILLOPN,
128 "operand exception")
129DO_ERROR_INFO(privileged_op, SIGILL, ILL_PRVOPC,
130 "privileged operation")
131DO_ERROR_INFO(special_op_exception, SIGILL, ILL_ILLOPN,
132 "special operation exception")
133DO_ERROR_INFO(transaction_exception, SIGILL, ILL_ILLOPN,
134 "transaction constraint exception")
135
136static inline void do_fp_trap(struct pt_regs *regs, __u32 fpc)
137{
138 int si_code = 0;
139 /* FPC[2] is Data Exception Code */
140 if ((fpc & 0x00000300) == 0) {
141 /* bits 6 and 7 of DXC are 0 iff IEEE exception */
142 if (fpc & 0x8000) /* invalid fp operation */
143 si_code = FPE_FLTINV;
144 else if (fpc & 0x4000) /* div by 0 */
145 si_code = FPE_FLTDIV;
146 else if (fpc & 0x2000) /* overflow */
147 si_code = FPE_FLTOVF;
148 else if (fpc & 0x1000) /* underflow */
149 si_code = FPE_FLTUND;
150 else if (fpc & 0x0800) /* inexact */
151 si_code = FPE_FLTRES;
152 }
153 do_trap(regs, SIGFPE, si_code, "floating point exception");
154}
155
156void translation_exception(struct pt_regs *regs)
157{
158 /* May never happen. */
159 panic("Translation exception");
160}
161
162void illegal_op(struct pt_regs *regs)
163{
164 siginfo_t info;
165 __u8 opcode[6];
166 __u16 __user *location;
167 int is_uprobe_insn = 0;
168 int signal = 0;
169
170 location = get_trap_ip(regs);
171
172 if (user_mode(regs)) {
173 if (get_user(*((__u16 *) opcode), (__u16 __user *) location))
174 return;
175 if (*((__u16 *) opcode) == S390_BREAKPOINT_U16) {
176 if (current->ptrace) {
177 info.si_signo = SIGTRAP;
178 info.si_errno = 0;
179 info.si_code = TRAP_BRKPT;
180 info.si_addr = location;
181 force_sig_info(SIGTRAP, &info, current);
182 } else
183 signal = SIGILL;
184#ifdef CONFIG_UPROBES
185 } else if (*((__u16 *) opcode) == UPROBE_SWBP_INSN) {
186 is_uprobe_insn = 1;
187#endif
188 } else
189 signal = SIGILL;
190 }
191 /*
192 * We got either an illegal op in kernel mode, or user space trapped
193 * on a uprobes illegal instruction. See if kprobes or uprobes picks
194 * it up. If not, SIGILL.
195 */
196 if (is_uprobe_insn || !user_mode(regs)) {
197 if (notify_die(DIE_BPT, "bpt", regs, 0,
198 3, SIGTRAP) != NOTIFY_STOP)
199 signal = SIGILL;
200 }
201 if (signal)
202 do_trap(regs, signal, ILL_ILLOPC, "illegal operation");
203}
204NOKPROBE_SYMBOL(illegal_op);
205
206DO_ERROR_INFO(specification_exception, SIGILL, ILL_ILLOPN,
207 "specification exception");
208
209void vector_exception(struct pt_regs *regs)
210{
211 int si_code, vic;
212
213 if (!MACHINE_HAS_VX) {
214 do_trap(regs, SIGILL, ILL_ILLOPN, "illegal operation");
215 return;
216 }
217
218 /* get vector interrupt code from fpc */
219 save_fpu_regs();
220 vic = (current->thread.fpu.fpc & 0xf00) >> 8;
221 switch (vic) {
222 case 1: /* invalid vector operation */
223 si_code = FPE_FLTINV;
224 break;
225 case 2: /* division by zero */
226 si_code = FPE_FLTDIV;
227 break;
228 case 3: /* overflow */
229 si_code = FPE_FLTOVF;
230 break;
231 case 4: /* underflow */
232 si_code = FPE_FLTUND;
233 break;
234 case 5: /* inexact */
235 si_code = FPE_FLTRES;
236 break;
237 default: /* unknown cause */
238 si_code = 0;
239 }
240 do_trap(regs, SIGFPE, si_code, "vector exception");
241}
242
243void data_exception(struct pt_regs *regs)
244{
245 int signal = 0;
246
247 save_fpu_regs();
248 if (current->thread.fpu.fpc & FPC_DXC_MASK)
249 signal = SIGFPE;
250 else
251 signal = SIGILL;
252 if (signal == SIGFPE)
253 do_fp_trap(regs, current->thread.fpu.fpc);
254 else if (signal)
255 do_trap(regs, signal, ILL_ILLOPN, "data exception");
256}
257
258void space_switch_exception(struct pt_regs *regs)
259{
260 /* Set user psw back to home space mode. */
261 if (user_mode(regs))
262 regs->psw.mask |= PSW_ASC_HOME;
263 /* Send SIGILL. */
264 do_trap(regs, SIGILL, ILL_PRVOPC, "space switch event");
265}
266
267void kernel_stack_overflow(struct pt_regs *regs)
268{
269 bust_spinlocks(1);
270 printk("Kernel stack overflow.\n");
271 show_regs(regs);
272 bust_spinlocks(0);
273 panic("Corrupt kernel stack, can't continue.");
274}
275NOKPROBE_SYMBOL(kernel_stack_overflow);
276
277void __init trap_init(void)
278{
279 local_mcck_enable();
280}