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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 <linux/kprobes.h>
17#include <linux/kdebug.h>
18#include <linux/extable.h>
19#include <linux/ptrace.h>
20#include <linux/sched.h>
21#include <linux/sched/debug.h>
22#include <linux/mm.h>
23#include <linux/slab.h>
24#include <linux/uaccess.h>
25#include <linux/cpu.h>
26#include <asm/fpu/api.h>
27#include "entry.h"
28
29static inline void __user *get_trap_ip(struct pt_regs *regs)
30{
31 unsigned long address;
32
33 if (regs->int_code & 0x200)
34 address = *(unsigned long *)(current->thread.trap_tdb + 24);
35 else
36 address = regs->psw.addr;
37 return (void __user *) (address - (regs->int_code >> 16));
38}
39
40int is_valid_bugaddr(unsigned long addr)
41{
42 return 1;
43}
44
45void do_report_trap(struct pt_regs *regs, int si_signo, int si_code, char *str)
46{
47 if (user_mode(regs)) {
48 force_sig_fault(si_signo, si_code, get_trap_ip(regs));
49 report_user_fault(regs, si_signo, 0);
50 } else {
51 const struct exception_table_entry *fixup;
52 fixup = s390_search_extables(regs->psw.addr);
53 if (fixup)
54 regs->psw.addr = extable_fixup(fixup);
55 else {
56 enum bug_trap_type btt;
57
58 btt = report_bug(regs->psw.addr, regs);
59 if (btt == BUG_TRAP_TYPE_WARN)
60 return;
61 die(regs, str);
62 }
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
86void default_trap_handler(struct pt_regs *regs)
87{
88 if (user_mode(regs)) {
89 report_user_fault(regs, SIGSEGV, 0);
90 do_exit(SIGSEGV);
91 } else
92 die(regs, "Unknown program exception");
93}
94
95#define DO_ERROR_INFO(name, signr, sicode, str) \
96void 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
148void translation_exception(struct pt_regs *regs)
149{
150 /* May never happen. */
151 panic("Translation exception");
152}
153
154void 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
196void vector_exception(struct pt_regs *regs)
197{
198 int si_code, vic;
199
200 if (!MACHINE_HAS_VX) {
201 do_trap(regs, SIGILL, ILL_ILLOPN, "illegal operation");
202 return;
203 }
204
205 /* get vector interrupt code from fpc */
206 save_fpu_regs();
207 vic = (current->thread.fpu.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
230void data_exception(struct pt_regs *regs)
231{
232 save_fpu_regs();
233 if (current->thread.fpu.fpc & FPC_DXC_MASK)
234 do_fp_trap(regs, current->thread.fpu.fpc);
235 else
236 do_trap(regs, SIGILL, ILL_ILLOPN, "data exception");
237}
238
239void 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
248void kernel_stack_overflow(struct pt_regs *regs)
249{
250 bust_spinlocks(1);
251 printk("Kernel stack overflow.\n");
252 show_regs(regs);
253 bust_spinlocks(0);
254 panic("Corrupt kernel stack, can't continue.");
255}
256NOKPROBE_SYMBOL(kernel_stack_overflow);
257
258void __init trap_init(void)
259{
260 sort_extable(__start_dma_ex_table, __stop_dma_ex_table);
261 local_mcck_enable();
262}
1/*
2 * arch/s390/kernel/traps.c
3 *
4 * S390 version
5 * Copyright (C) 1999,2000 IBM Deutschland Entwicklung GmbH, IBM Corporation
6 * Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
7 * Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com),
8 *
9 * Derived from "arch/i386/kernel/traps.c"
10 * Copyright (C) 1991, 1992 Linus Torvalds
11 */
12
13/*
14 * 'Traps.c' handles hardware traps and faults after we have saved some
15 * state in 'asm.s'.
16 */
17#include <linux/sched.h>
18#include <linux/kernel.h>
19#include <linux/string.h>
20#include <linux/errno.h>
21#include <linux/ptrace.h>
22#include <linux/timer.h>
23#include <linux/mm.h>
24#include <linux/smp.h>
25#include <linux/init.h>
26#include <linux/interrupt.h>
27#include <linux/seq_file.h>
28#include <linux/delay.h>
29#include <linux/module.h>
30#include <linux/kdebug.h>
31#include <linux/kallsyms.h>
32#include <linux/reboot.h>
33#include <linux/kprobes.h>
34#include <linux/bug.h>
35#include <linux/utsname.h>
36#include <asm/uaccess.h>
37#include <asm/io.h>
38#include <linux/atomic.h>
39#include <asm/mathemu.h>
40#include <asm/cpcmd.h>
41#include <asm/lowcore.h>
42#include <asm/debug.h>
43#include <asm/ipl.h>
44#include "entry.h"
45
46void (*pgm_check_table[128])(struct pt_regs *regs);
47
48int show_unhandled_signals = 1;
49
50#define stack_pointer ({ void **sp; asm("la %0,0(15)" : "=&d" (sp)); sp; })
51
52#ifndef CONFIG_64BIT
53#define LONG "%08lx "
54#define FOURLONG "%08lx %08lx %08lx %08lx\n"
55static int kstack_depth_to_print = 12;
56#else /* CONFIG_64BIT */
57#define LONG "%016lx "
58#define FOURLONG "%016lx %016lx %016lx %016lx\n"
59static int kstack_depth_to_print = 20;
60#endif /* CONFIG_64BIT */
61
62/*
63 * For show_trace we have tree different stack to consider:
64 * - the panic stack which is used if the kernel stack has overflown
65 * - the asynchronous interrupt stack (cpu related)
66 * - the synchronous kernel stack (process related)
67 * The stack trace can start at any of the three stack and can potentially
68 * touch all of them. The order is: panic stack, async stack, sync stack.
69 */
70static unsigned long
71__show_trace(unsigned long sp, unsigned long low, unsigned long high)
72{
73 struct stack_frame *sf;
74 struct pt_regs *regs;
75
76 while (1) {
77 sp = sp & PSW_ADDR_INSN;
78 if (sp < low || sp > high - sizeof(*sf))
79 return sp;
80 sf = (struct stack_frame *) sp;
81 printk("([<%016lx>] ", sf->gprs[8] & PSW_ADDR_INSN);
82 print_symbol("%s)\n", sf->gprs[8] & PSW_ADDR_INSN);
83 /* Follow the backchain. */
84 while (1) {
85 low = sp;
86 sp = sf->back_chain & PSW_ADDR_INSN;
87 if (!sp)
88 break;
89 if (sp <= low || sp > high - sizeof(*sf))
90 return sp;
91 sf = (struct stack_frame *) sp;
92 printk(" [<%016lx>] ", sf->gprs[8] & PSW_ADDR_INSN);
93 print_symbol("%s\n", sf->gprs[8] & PSW_ADDR_INSN);
94 }
95 /* Zero backchain detected, check for interrupt frame. */
96 sp = (unsigned long) (sf + 1);
97 if (sp <= low || sp > high - sizeof(*regs))
98 return sp;
99 regs = (struct pt_regs *) sp;
100 printk(" [<%016lx>] ", regs->psw.addr & PSW_ADDR_INSN);
101 print_symbol("%s\n", regs->psw.addr & PSW_ADDR_INSN);
102 low = sp;
103 sp = regs->gprs[15];
104 }
105}
106
107static void show_trace(struct task_struct *task, unsigned long *stack)
108{
109 register unsigned long __r15 asm ("15");
110 unsigned long sp;
111
112 sp = (unsigned long) stack;
113 if (!sp)
114 sp = task ? task->thread.ksp : __r15;
115 printk("Call Trace:\n");
116#ifdef CONFIG_CHECK_STACK
117 sp = __show_trace(sp, S390_lowcore.panic_stack - 4096,
118 S390_lowcore.panic_stack);
119#endif
120 sp = __show_trace(sp, S390_lowcore.async_stack - ASYNC_SIZE,
121 S390_lowcore.async_stack);
122 if (task)
123 __show_trace(sp, (unsigned long) task_stack_page(task),
124 (unsigned long) task_stack_page(task) + THREAD_SIZE);
125 else
126 __show_trace(sp, S390_lowcore.thread_info,
127 S390_lowcore.thread_info + THREAD_SIZE);
128 if (!task)
129 task = current;
130 debug_show_held_locks(task);
131}
132
133void show_stack(struct task_struct *task, unsigned long *sp)
134{
135 register unsigned long * __r15 asm ("15");
136 unsigned long *stack;
137 int i;
138
139 if (!sp)
140 stack = task ? (unsigned long *) task->thread.ksp : __r15;
141 else
142 stack = sp;
143
144 for (i = 0; i < kstack_depth_to_print; i++) {
145 if (((addr_t) stack & (THREAD_SIZE-1)) == 0)
146 break;
147 if ((i * sizeof(long) % 32) == 0)
148 printk("%s ", i == 0 ? "" : "\n");
149 printk(LONG, *stack++);
150 }
151 printk("\n");
152 show_trace(task, sp);
153}
154
155static void show_last_breaking_event(struct pt_regs *regs)
156{
157#ifdef CONFIG_64BIT
158 printk("Last Breaking-Event-Address:\n");
159 printk(" [<%016lx>] ", regs->args[0] & PSW_ADDR_INSN);
160 print_symbol("%s\n", regs->args[0] & PSW_ADDR_INSN);
161#endif
162}
163
164/*
165 * The architecture-independent dump_stack generator
166 */
167void dump_stack(void)
168{
169 printk("CPU: %d %s %s %.*s\n",
170 task_thread_info(current)->cpu, print_tainted(),
171 init_utsname()->release,
172 (int)strcspn(init_utsname()->version, " "),
173 init_utsname()->version);
174 printk("Process %s (pid: %d, task: %p, ksp: %p)\n",
175 current->comm, current->pid, current,
176 (void *) current->thread.ksp);
177 show_stack(NULL, NULL);
178}
179EXPORT_SYMBOL(dump_stack);
180
181static inline int mask_bits(struct pt_regs *regs, unsigned long bits)
182{
183 return (regs->psw.mask & bits) / ((~bits + 1) & bits);
184}
185
186void show_registers(struct pt_regs *regs)
187{
188 char *mode;
189
190 mode = (regs->psw.mask & PSW_MASK_PSTATE) ? "User" : "Krnl";
191 printk("%s PSW : %p %p",
192 mode, (void *) regs->psw.mask,
193 (void *) regs->psw.addr);
194 print_symbol(" (%s)\n", regs->psw.addr & PSW_ADDR_INSN);
195 printk(" R:%x T:%x IO:%x EX:%x Key:%x M:%x W:%x "
196 "P:%x AS:%x CC:%x PM:%x", mask_bits(regs, PSW_MASK_PER),
197 mask_bits(regs, PSW_MASK_DAT), mask_bits(regs, PSW_MASK_IO),
198 mask_bits(regs, PSW_MASK_EXT), mask_bits(regs, PSW_MASK_KEY),
199 mask_bits(regs, PSW_MASK_MCHECK), mask_bits(regs, PSW_MASK_WAIT),
200 mask_bits(regs, PSW_MASK_PSTATE), mask_bits(regs, PSW_MASK_ASC),
201 mask_bits(regs, PSW_MASK_CC), mask_bits(regs, PSW_MASK_PM));
202#ifdef CONFIG_64BIT
203 printk(" EA:%x", mask_bits(regs, PSW_MASK_EA | PSW_MASK_BA));
204#endif
205 printk("\n%s GPRS: " FOURLONG, mode,
206 regs->gprs[0], regs->gprs[1], regs->gprs[2], regs->gprs[3]);
207 printk(" " FOURLONG,
208 regs->gprs[4], regs->gprs[5], regs->gprs[6], regs->gprs[7]);
209 printk(" " FOURLONG,
210 regs->gprs[8], regs->gprs[9], regs->gprs[10], regs->gprs[11]);
211 printk(" " FOURLONG,
212 regs->gprs[12], regs->gprs[13], regs->gprs[14], regs->gprs[15]);
213
214 show_code(regs);
215}
216
217void show_regs(struct pt_regs *regs)
218{
219 print_modules();
220 printk("CPU: %d %s %s %.*s\n",
221 task_thread_info(current)->cpu, print_tainted(),
222 init_utsname()->release,
223 (int)strcspn(init_utsname()->version, " "),
224 init_utsname()->version);
225 printk("Process %s (pid: %d, task: %p, ksp: %p)\n",
226 current->comm, current->pid, current,
227 (void *) current->thread.ksp);
228 show_registers(regs);
229 /* Show stack backtrace if pt_regs is from kernel mode */
230 if (!(regs->psw.mask & PSW_MASK_PSTATE))
231 show_trace(NULL, (unsigned long *) regs->gprs[15]);
232 show_last_breaking_event(regs);
233}
234
235static DEFINE_SPINLOCK(die_lock);
236
237void die(struct pt_regs *regs, const char *str)
238{
239 static int die_counter;
240
241 oops_enter();
242 lgr_info_log();
243 debug_stop_all();
244 console_verbose();
245 spin_lock_irq(&die_lock);
246 bust_spinlocks(1);
247 printk("%s: %04x [#%d] ", str, regs->int_code & 0xffff, ++die_counter);
248#ifdef CONFIG_PREEMPT
249 printk("PREEMPT ");
250#endif
251#ifdef CONFIG_SMP
252 printk("SMP ");
253#endif
254#ifdef CONFIG_DEBUG_PAGEALLOC
255 printk("DEBUG_PAGEALLOC");
256#endif
257 printk("\n");
258 notify_die(DIE_OOPS, str, regs, 0, regs->int_code & 0xffff, SIGSEGV);
259 show_regs(regs);
260 bust_spinlocks(0);
261 add_taint(TAINT_DIE);
262 spin_unlock_irq(&die_lock);
263 if (in_interrupt())
264 panic("Fatal exception in interrupt");
265 if (panic_on_oops)
266 panic("Fatal exception: panic_on_oops");
267 oops_exit();
268 do_exit(SIGSEGV);
269}
270
271static inline void report_user_fault(struct pt_regs *regs, int signr)
272{
273 if ((task_pid_nr(current) > 1) && !show_unhandled_signals)
274 return;
275 if (!unhandled_signal(current, signr))
276 return;
277 if (!printk_ratelimit())
278 return;
279 printk("User process fault: interruption code 0x%X ", regs->int_code);
280 print_vma_addr("in ", regs->psw.addr & PSW_ADDR_INSN);
281 printk("\n");
282 show_regs(regs);
283}
284
285int is_valid_bugaddr(unsigned long addr)
286{
287 return 1;
288}
289
290static inline void __user *get_psw_address(struct pt_regs *regs)
291{
292 return (void __user *)
293 ((regs->psw.addr - (regs->int_code >> 16)) & PSW_ADDR_INSN);
294}
295
296static void __kprobes do_trap(struct pt_regs *regs,
297 int si_signo, int si_code, char *str)
298{
299 siginfo_t info;
300
301 if (notify_die(DIE_TRAP, str, regs, 0,
302 regs->int_code, si_signo) == NOTIFY_STOP)
303 return;
304
305 if (regs->psw.mask & PSW_MASK_PSTATE) {
306 info.si_signo = si_signo;
307 info.si_errno = 0;
308 info.si_code = si_code;
309 info.si_addr = get_psw_address(regs);
310 force_sig_info(si_signo, &info, current);
311 report_user_fault(regs, si_signo);
312 } else {
313 const struct exception_table_entry *fixup;
314 fixup = search_exception_tables(regs->psw.addr & PSW_ADDR_INSN);
315 if (fixup)
316 regs->psw.addr = fixup->fixup | PSW_ADDR_AMODE;
317 else {
318 enum bug_trap_type btt;
319
320 btt = report_bug(regs->psw.addr & PSW_ADDR_INSN, regs);
321 if (btt == BUG_TRAP_TYPE_WARN)
322 return;
323 die(regs, str);
324 }
325 }
326}
327
328void __kprobes do_per_trap(struct pt_regs *regs)
329{
330 siginfo_t info;
331
332 if (notify_die(DIE_SSTEP, "sstep", regs, 0, 0, SIGTRAP) == NOTIFY_STOP)
333 return;
334 if (!current->ptrace)
335 return;
336 info.si_signo = SIGTRAP;
337 info.si_errno = 0;
338 info.si_code = TRAP_HWBKPT;
339 info.si_addr =
340 (void __force __user *) current->thread.per_event.address;
341 force_sig_info(SIGTRAP, &info, current);
342}
343
344static void default_trap_handler(struct pt_regs *regs)
345{
346 if (regs->psw.mask & PSW_MASK_PSTATE) {
347 report_user_fault(regs, SIGSEGV);
348 do_exit(SIGSEGV);
349 } else
350 die(regs, "Unknown program exception");
351}
352
353#define DO_ERROR_INFO(name, signr, sicode, str) \
354static void name(struct pt_regs *regs) \
355{ \
356 do_trap(regs, signr, sicode, str); \
357}
358
359DO_ERROR_INFO(addressing_exception, SIGILL, ILL_ILLADR,
360 "addressing exception")
361DO_ERROR_INFO(execute_exception, SIGILL, ILL_ILLOPN,
362 "execute exception")
363DO_ERROR_INFO(divide_exception, SIGFPE, FPE_INTDIV,
364 "fixpoint divide exception")
365DO_ERROR_INFO(overflow_exception, SIGFPE, FPE_INTOVF,
366 "fixpoint overflow exception")
367DO_ERROR_INFO(hfp_overflow_exception, SIGFPE, FPE_FLTOVF,
368 "HFP overflow exception")
369DO_ERROR_INFO(hfp_underflow_exception, SIGFPE, FPE_FLTUND,
370 "HFP underflow exception")
371DO_ERROR_INFO(hfp_significance_exception, SIGFPE, FPE_FLTRES,
372 "HFP significance exception")
373DO_ERROR_INFO(hfp_divide_exception, SIGFPE, FPE_FLTDIV,
374 "HFP divide exception")
375DO_ERROR_INFO(hfp_sqrt_exception, SIGFPE, FPE_FLTINV,
376 "HFP square root exception")
377DO_ERROR_INFO(operand_exception, SIGILL, ILL_ILLOPN,
378 "operand exception")
379DO_ERROR_INFO(privileged_op, SIGILL, ILL_PRVOPC,
380 "privileged operation")
381DO_ERROR_INFO(special_op_exception, SIGILL, ILL_ILLOPN,
382 "special operation exception")
383DO_ERROR_INFO(translation_exception, SIGILL, ILL_ILLOPN,
384 "translation exception")
385
386static inline void do_fp_trap(struct pt_regs *regs, int fpc)
387{
388 int si_code = 0;
389 /* FPC[2] is Data Exception Code */
390 if ((fpc & 0x00000300) == 0) {
391 /* bits 6 and 7 of DXC are 0 iff IEEE exception */
392 if (fpc & 0x8000) /* invalid fp operation */
393 si_code = FPE_FLTINV;
394 else if (fpc & 0x4000) /* div by 0 */
395 si_code = FPE_FLTDIV;
396 else if (fpc & 0x2000) /* overflow */
397 si_code = FPE_FLTOVF;
398 else if (fpc & 0x1000) /* underflow */
399 si_code = FPE_FLTUND;
400 else if (fpc & 0x0800) /* inexact */
401 si_code = FPE_FLTRES;
402 }
403 do_trap(regs, SIGFPE, si_code, "floating point exception");
404}
405
406static void __kprobes illegal_op(struct pt_regs *regs)
407{
408 siginfo_t info;
409 __u8 opcode[6];
410 __u16 __user *location;
411 int signal = 0;
412
413 location = get_psw_address(regs);
414
415 if (regs->psw.mask & PSW_MASK_PSTATE) {
416 if (get_user(*((__u16 *) opcode), (__u16 __user *) location))
417 return;
418 if (*((__u16 *) opcode) == S390_BREAKPOINT_U16) {
419 if (current->ptrace) {
420 info.si_signo = SIGTRAP;
421 info.si_errno = 0;
422 info.si_code = TRAP_BRKPT;
423 info.si_addr = location;
424 force_sig_info(SIGTRAP, &info, current);
425 } else
426 signal = SIGILL;
427#ifdef CONFIG_MATHEMU
428 } else if (opcode[0] == 0xb3) {
429 if (get_user(*((__u16 *) (opcode+2)), location+1))
430 return;
431 signal = math_emu_b3(opcode, regs);
432 } else if (opcode[0] == 0xed) {
433 if (get_user(*((__u32 *) (opcode+2)),
434 (__u32 __user *)(location+1)))
435 return;
436 signal = math_emu_ed(opcode, regs);
437 } else if (*((__u16 *) opcode) == 0xb299) {
438 if (get_user(*((__u16 *) (opcode+2)), location+1))
439 return;
440 signal = math_emu_srnm(opcode, regs);
441 } else if (*((__u16 *) opcode) == 0xb29c) {
442 if (get_user(*((__u16 *) (opcode+2)), location+1))
443 return;
444 signal = math_emu_stfpc(opcode, regs);
445 } else if (*((__u16 *) opcode) == 0xb29d) {
446 if (get_user(*((__u16 *) (opcode+2)), location+1))
447 return;
448 signal = math_emu_lfpc(opcode, regs);
449#endif
450 } else
451 signal = SIGILL;
452 } else {
453 /*
454 * If we get an illegal op in kernel mode, send it through the
455 * kprobes notifier. If kprobes doesn't pick it up, SIGILL
456 */
457 if (notify_die(DIE_BPT, "bpt", regs, 0,
458 3, SIGTRAP) != NOTIFY_STOP)
459 signal = SIGILL;
460 }
461
462#ifdef CONFIG_MATHEMU
463 if (signal == SIGFPE)
464 do_fp_trap(regs, current->thread.fp_regs.fpc);
465 else if (signal == SIGSEGV)
466 do_trap(regs, signal, SEGV_MAPERR, "user address fault");
467 else
468#endif
469 if (signal)
470 do_trap(regs, signal, ILL_ILLOPC, "illegal operation");
471}
472
473
474#ifdef CONFIG_MATHEMU
475void specification_exception(struct pt_regs *regs)
476{
477 __u8 opcode[6];
478 __u16 __user *location = NULL;
479 int signal = 0;
480
481 location = (__u16 __user *) get_psw_address(regs);
482
483 if (regs->psw.mask & PSW_MASK_PSTATE) {
484 get_user(*((__u16 *) opcode), location);
485 switch (opcode[0]) {
486 case 0x28: /* LDR Rx,Ry */
487 signal = math_emu_ldr(opcode);
488 break;
489 case 0x38: /* LER Rx,Ry */
490 signal = math_emu_ler(opcode);
491 break;
492 case 0x60: /* STD R,D(X,B) */
493 get_user(*((__u16 *) (opcode+2)), location+1);
494 signal = math_emu_std(opcode, regs);
495 break;
496 case 0x68: /* LD R,D(X,B) */
497 get_user(*((__u16 *) (opcode+2)), location+1);
498 signal = math_emu_ld(opcode, regs);
499 break;
500 case 0x70: /* STE R,D(X,B) */
501 get_user(*((__u16 *) (opcode+2)), location+1);
502 signal = math_emu_ste(opcode, regs);
503 break;
504 case 0x78: /* LE R,D(X,B) */
505 get_user(*((__u16 *) (opcode+2)), location+1);
506 signal = math_emu_le(opcode, regs);
507 break;
508 default:
509 signal = SIGILL;
510 break;
511 }
512 } else
513 signal = SIGILL;
514
515 if (signal == SIGFPE)
516 do_fp_trap(regs, current->thread.fp_regs.fpc);
517 else if (signal)
518 do_trap(regs, signal, ILL_ILLOPN, "specification exception");
519}
520#else
521DO_ERROR_INFO(specification_exception, SIGILL, ILL_ILLOPN,
522 "specification exception");
523#endif
524
525static void data_exception(struct pt_regs *regs)
526{
527 __u16 __user *location;
528 int signal = 0;
529
530 location = get_psw_address(regs);
531
532 if (MACHINE_HAS_IEEE)
533 asm volatile("stfpc %0" : "=m" (current->thread.fp_regs.fpc));
534
535#ifdef CONFIG_MATHEMU
536 else if (regs->psw.mask & PSW_MASK_PSTATE) {
537 __u8 opcode[6];
538 get_user(*((__u16 *) opcode), location);
539 switch (opcode[0]) {
540 case 0x28: /* LDR Rx,Ry */
541 signal = math_emu_ldr(opcode);
542 break;
543 case 0x38: /* LER Rx,Ry */
544 signal = math_emu_ler(opcode);
545 break;
546 case 0x60: /* STD R,D(X,B) */
547 get_user(*((__u16 *) (opcode+2)), location+1);
548 signal = math_emu_std(opcode, regs);
549 break;
550 case 0x68: /* LD R,D(X,B) */
551 get_user(*((__u16 *) (opcode+2)), location+1);
552 signal = math_emu_ld(opcode, regs);
553 break;
554 case 0x70: /* STE R,D(X,B) */
555 get_user(*((__u16 *) (opcode+2)), location+1);
556 signal = math_emu_ste(opcode, regs);
557 break;
558 case 0x78: /* LE R,D(X,B) */
559 get_user(*((__u16 *) (opcode+2)), location+1);
560 signal = math_emu_le(opcode, regs);
561 break;
562 case 0xb3:
563 get_user(*((__u16 *) (opcode+2)), location+1);
564 signal = math_emu_b3(opcode, regs);
565 break;
566 case 0xed:
567 get_user(*((__u32 *) (opcode+2)),
568 (__u32 __user *)(location+1));
569 signal = math_emu_ed(opcode, regs);
570 break;
571 case 0xb2:
572 if (opcode[1] == 0x99) {
573 get_user(*((__u16 *) (opcode+2)), location+1);
574 signal = math_emu_srnm(opcode, regs);
575 } else if (opcode[1] == 0x9c) {
576 get_user(*((__u16 *) (opcode+2)), location+1);
577 signal = math_emu_stfpc(opcode, regs);
578 } else if (opcode[1] == 0x9d) {
579 get_user(*((__u16 *) (opcode+2)), location+1);
580 signal = math_emu_lfpc(opcode, regs);
581 } else
582 signal = SIGILL;
583 break;
584 default:
585 signal = SIGILL;
586 break;
587 }
588 }
589#endif
590 if (current->thread.fp_regs.fpc & FPC_DXC_MASK)
591 signal = SIGFPE;
592 else
593 signal = SIGILL;
594 if (signal == SIGFPE)
595 do_fp_trap(regs, current->thread.fp_regs.fpc);
596 else if (signal)
597 do_trap(regs, signal, ILL_ILLOPN, "data exception");
598}
599
600static void space_switch_exception(struct pt_regs *regs)
601{
602 /* Set user psw back to home space mode. */
603 if (regs->psw.mask & PSW_MASK_PSTATE)
604 regs->psw.mask |= PSW_ASC_HOME;
605 /* Send SIGILL. */
606 do_trap(regs, SIGILL, ILL_PRVOPC, "space switch event");
607}
608
609void __kprobes kernel_stack_overflow(struct pt_regs * regs)
610{
611 bust_spinlocks(1);
612 printk("Kernel stack overflow.\n");
613 show_regs(regs);
614 bust_spinlocks(0);
615 panic("Corrupt kernel stack, can't continue.");
616}
617
618/* init is done in lowcore.S and head.S */
619
620void __init trap_init(void)
621{
622 int i;
623
624 for (i = 0; i < 128; i++)
625 pgm_check_table[i] = &default_trap_handler;
626 pgm_check_table[1] = &illegal_op;
627 pgm_check_table[2] = &privileged_op;
628 pgm_check_table[3] = &execute_exception;
629 pgm_check_table[4] = &do_protection_exception;
630 pgm_check_table[5] = &addressing_exception;
631 pgm_check_table[6] = &specification_exception;
632 pgm_check_table[7] = &data_exception;
633 pgm_check_table[8] = &overflow_exception;
634 pgm_check_table[9] = ÷_exception;
635 pgm_check_table[0x0A] = &overflow_exception;
636 pgm_check_table[0x0B] = ÷_exception;
637 pgm_check_table[0x0C] = &hfp_overflow_exception;
638 pgm_check_table[0x0D] = &hfp_underflow_exception;
639 pgm_check_table[0x0E] = &hfp_significance_exception;
640 pgm_check_table[0x0F] = &hfp_divide_exception;
641 pgm_check_table[0x10] = &do_dat_exception;
642 pgm_check_table[0x11] = &do_dat_exception;
643 pgm_check_table[0x12] = &translation_exception;
644 pgm_check_table[0x13] = &special_op_exception;
645#ifdef CONFIG_64BIT
646 pgm_check_table[0x38] = &do_asce_exception;
647 pgm_check_table[0x39] = &do_dat_exception;
648 pgm_check_table[0x3A] = &do_dat_exception;
649 pgm_check_table[0x3B] = &do_dat_exception;
650#endif /* CONFIG_64BIT */
651 pgm_check_table[0x15] = &operand_exception;
652 pgm_check_table[0x1C] = &space_switch_exception;
653 pgm_check_table[0x1D] = &hfp_sqrt_exception;
654 /* Enable machine checks early. */
655 local_mcck_enable();
656}