2 * arch/s390/kernel/traps.c
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),
9 * Derived from "arch/i386/kernel/traps.c"
10 * Copyright (C) 1991, 1992 Linus Torvalds
14 * 'Traps.c' handles hardware traps and faults after we have saved some
17 #include <linux/config.h>
18 #include <linux/sched.h>
19 #include <linux/kernel.h>
20 #include <linux/string.h>
21 #include <linux/errno.h>
22 #include <linux/ptrace.h>
23 #include <linux/timer.h>
25 #include <linux/smp.h>
26 #include <linux/smp_lock.h>
27 #include <linux/init.h>
28 #include <linux/interrupt.h>
29 #include <linux/delay.h>
30 #include <linux/module.h>
31 #include <linux/kallsyms.h>
32 #include <linux/reboot.h>
34 #include <asm/system.h>
35 #include <asm/uaccess.h>
37 #include <asm/atomic.h>
38 #include <asm/mathemu.h>
39 #include <asm/cpcmd.h>
40 #include <asm/s390_ext.h>
41 #include <asm/lowcore.h>
42 #include <asm/debug.h>
44 /* Called from entry.S only */
45 extern void handle_per_exception(struct pt_regs *regs);
47 typedef void pgm_check_handler_t(struct pt_regs *, long);
48 pgm_check_handler_t *pgm_check_table[128];
51 #ifdef CONFIG_PROCESS_DEBUG
52 int sysctl_userprocess_debug = 1;
54 int sysctl_userprocess_debug = 0;
58 extern pgm_check_handler_t do_protection_exception;
59 extern pgm_check_handler_t do_dat_exception;
61 extern int pfault_init(void);
62 extern void pfault_fini(void);
63 extern void pfault_interrupt(struct pt_regs *regs, __u16 error_code);
64 static ext_int_info_t ext_int_pfault;
66 extern pgm_check_handler_t do_monitor_call;
68 #define stack_pointer ({ void **sp; asm("la %0,0(15)" : "=&d" (sp)); sp; })
71 #define FOURLONG "%08lx %08lx %08lx %08lx\n"
72 static int kstack_depth_to_print = 12;
73 #else /* CONFIG_64BIT */
74 #define FOURLONG "%016lx %016lx %016lx %016lx\n"
75 static int kstack_depth_to_print = 20;
76 #endif /* CONFIG_64BIT */
79 * For show_trace we have tree different stack to consider:
80 * - the panic stack which is used if the kernel stack has overflown
81 * - the asynchronous interrupt stack (cpu related)
82 * - the synchronous kernel stack (process related)
83 * The stack trace can start at any of the three stack and can potentially
84 * touch all of them. The order is: panic stack, async stack, sync stack.
87 __show_trace(unsigned long sp, unsigned long low, unsigned long high)
89 struct stack_frame *sf;
93 sp = sp & PSW_ADDR_INSN;
94 if (sp < low || sp > high - sizeof(*sf))
96 sf = (struct stack_frame *) sp;
97 printk("([<%016lx>] ", sf->gprs[8] & PSW_ADDR_INSN);
98 print_symbol("%s)\n", sf->gprs[8] & PSW_ADDR_INSN);
99 /* Follow the backchain. */
102 sp = sf->back_chain & PSW_ADDR_INSN;
105 if (sp <= low || sp > high - sizeof(*sf))
107 sf = (struct stack_frame *) sp;
108 printk(" [<%016lx>] ", sf->gprs[8] & PSW_ADDR_INSN);
109 print_symbol("%s\n", sf->gprs[8] & PSW_ADDR_INSN);
111 /* Zero backchain detected, check for interrupt frame. */
112 sp = (unsigned long) (sf + 1);
113 if (sp <= low || sp > high - sizeof(*regs))
115 regs = (struct pt_regs *) sp;
116 printk(" [<%016lx>] ", regs->psw.addr & PSW_ADDR_INSN);
117 print_symbol("%s\n", regs->psw.addr & PSW_ADDR_INSN);
123 void show_trace(struct task_struct *task, unsigned long * stack)
125 register unsigned long __r15 asm ("15");
128 sp = (unsigned long) stack;
130 sp = task ? task->thread.ksp : __r15;
131 printk("Call Trace:\n");
132 #ifdef CONFIG_CHECK_STACK
133 sp = __show_trace(sp, S390_lowcore.panic_stack - 4096,
134 S390_lowcore.panic_stack);
136 sp = __show_trace(sp, S390_lowcore.async_stack - ASYNC_SIZE,
137 S390_lowcore.async_stack);
139 __show_trace(sp, (unsigned long) task_stack_page(task),
140 (unsigned long) task_stack_page(task) + THREAD_SIZE);
142 __show_trace(sp, S390_lowcore.thread_info,
143 S390_lowcore.thread_info + THREAD_SIZE);
147 void show_stack(struct task_struct *task, unsigned long *sp)
149 register unsigned long * __r15 asm ("15");
150 unsigned long *stack;
154 stack = task ? (unsigned long *) task->thread.ksp : __r15;
158 for (i = 0; i < kstack_depth_to_print; i++) {
159 if (((addr_t) stack & (THREAD_SIZE-1)) == 0)
161 if (i && ((i * sizeof (long) % 32) == 0))
163 printk("%p ", (void *)*stack++);
166 show_trace(task, sp);
170 * The architecture-independent dump_stack generator
172 void dump_stack(void)
177 EXPORT_SYMBOL(dump_stack);
179 void show_registers(struct pt_regs *regs)
185 mode = (regs->psw.mask & PSW_MASK_PSTATE) ? "User" : "Krnl";
186 printk("%s PSW : %p %p",
187 mode, (void *) regs->psw.mask,
188 (void *) regs->psw.addr);
189 print_symbol(" (%s)\n", regs->psw.addr & PSW_ADDR_INSN);
190 printk("%s GPRS: " FOURLONG, mode,
191 regs->gprs[0], regs->gprs[1], regs->gprs[2], regs->gprs[3]);
193 regs->gprs[4], regs->gprs[5], regs->gprs[6], regs->gprs[7]);
195 regs->gprs[8], regs->gprs[9], regs->gprs[10], regs->gprs[11]);
197 regs->gprs[12], regs->gprs[13], regs->gprs[14], regs->gprs[15]);
200 /* FIXME: this isn't needed any more but it changes the ksymoops
201 * input. To remove or not to remove ... */
202 save_access_regs(regs->acrs);
203 printk("%s ACRS: %08x %08x %08x %08x\n", mode,
204 regs->acrs[0], regs->acrs[1], regs->acrs[2], regs->acrs[3]);
205 printk(" %08x %08x %08x %08x\n",
206 regs->acrs[4], regs->acrs[5], regs->acrs[6], regs->acrs[7]);
207 printk(" %08x %08x %08x %08x\n",
208 regs->acrs[8], regs->acrs[9], regs->acrs[10], regs->acrs[11]);
209 printk(" %08x %08x %08x %08x\n",
210 regs->acrs[12], regs->acrs[13], regs->acrs[14], regs->acrs[15]);
214 * Print the first 20 byte of the instruction stream at the
218 if (regs->psw.mask & PSW_MASK_PSTATE)
222 printk("%s Code: ", mode);
223 for (i = 0; i < 20; i++) {
225 if (__get_user(c, (char __user *)(regs->psw.addr + i))) {
236 /* This is called from fs/proc/array.c */
237 char *task_show_regs(struct task_struct *task, char *buffer)
239 struct pt_regs *regs;
241 regs = task_pt_regs(task);
242 buffer += sprintf(buffer, "task: %p, ksp: %p\n",
243 task, (void *)task->thread.ksp);
244 buffer += sprintf(buffer, "User PSW : %p %p\n",
245 (void *) regs->psw.mask, (void *)regs->psw.addr);
247 buffer += sprintf(buffer, "User GPRS: " FOURLONG,
248 regs->gprs[0], regs->gprs[1],
249 regs->gprs[2], regs->gprs[3]);
250 buffer += sprintf(buffer, " " FOURLONG,
251 regs->gprs[4], regs->gprs[5],
252 regs->gprs[6], regs->gprs[7]);
253 buffer += sprintf(buffer, " " FOURLONG,
254 regs->gprs[8], regs->gprs[9],
255 regs->gprs[10], regs->gprs[11]);
256 buffer += sprintf(buffer, " " FOURLONG,
257 regs->gprs[12], regs->gprs[13],
258 regs->gprs[14], regs->gprs[15]);
259 buffer += sprintf(buffer, "User ACRS: %08x %08x %08x %08x\n",
260 task->thread.acrs[0], task->thread.acrs[1],
261 task->thread.acrs[2], task->thread.acrs[3]);
262 buffer += sprintf(buffer, " %08x %08x %08x %08x\n",
263 task->thread.acrs[4], task->thread.acrs[5],
264 task->thread.acrs[6], task->thread.acrs[7]);
265 buffer += sprintf(buffer, " %08x %08x %08x %08x\n",
266 task->thread.acrs[8], task->thread.acrs[9],
267 task->thread.acrs[10], task->thread.acrs[11]);
268 buffer += sprintf(buffer, " %08x %08x %08x %08x\n",
269 task->thread.acrs[12], task->thread.acrs[13],
270 task->thread.acrs[14], task->thread.acrs[15]);
274 DEFINE_SPINLOCK(die_lock);
276 void die(const char * str, struct pt_regs * regs, long err)
278 static int die_counter;
282 spin_lock_irq(&die_lock);
284 printk("%s: %04lx [#%d]\n", str, err & 0xffff, ++die_counter);
287 spin_unlock_irq(&die_lock);
289 panic("Fatal exception in interrupt");
291 panic("Fatal exception: panic_on_oops");
296 report_user_fault(long interruption_code, struct pt_regs *regs)
298 #if defined(CONFIG_SYSCTL)
299 if (!sysctl_userprocess_debug)
302 #if defined(CONFIG_SYSCTL) || defined(CONFIG_PROCESS_DEBUG)
303 printk("User process fault: interruption code 0x%lX\n",
309 static void inline do_trap(long interruption_code, int signr, char *str,
310 struct pt_regs *regs, siginfo_t *info)
313 * We got all needed information from the lowcore and can
314 * now safely switch on interrupts.
316 if (regs->psw.mask & PSW_MASK_PSTATE)
319 if (regs->psw.mask & PSW_MASK_PSTATE) {
320 struct task_struct *tsk = current;
322 tsk->thread.trap_no = interruption_code & 0xffff;
323 force_sig_info(signr, info, tsk);
324 report_user_fault(interruption_code, regs);
326 const struct exception_table_entry *fixup;
327 fixup = search_exception_tables(regs->psw.addr & PSW_ADDR_INSN);
329 regs->psw.addr = fixup->fixup | PSW_ADDR_AMODE;
331 die(str, regs, interruption_code);
335 static inline void *get_check_address(struct pt_regs *regs)
337 return (void *)((regs->psw.addr-S390_lowcore.pgm_ilc) & PSW_ADDR_INSN);
340 void do_single_step(struct pt_regs *regs)
342 if ((current->ptrace & PT_PTRACED) != 0)
343 force_sig(SIGTRAP, current);
347 default_trap_handler(struct pt_regs * regs, long interruption_code)
349 if (regs->psw.mask & PSW_MASK_PSTATE) {
352 report_user_fault(interruption_code, regs);
354 die("Unknown program exception", regs, interruption_code);
357 #define DO_ERROR_INFO(signr, str, name, sicode, siaddr) \
358 asmlinkage void name(struct pt_regs * regs, long interruption_code) \
361 info.si_signo = signr; \
363 info.si_code = sicode; \
364 info.si_addr = (void *)siaddr; \
365 do_trap(interruption_code, signr, str, regs, &info); \
368 DO_ERROR_INFO(SIGILL, "addressing exception", addressing_exception,
369 ILL_ILLADR, get_check_address(regs))
370 DO_ERROR_INFO(SIGILL, "execute exception", execute_exception,
371 ILL_ILLOPN, get_check_address(regs))
372 DO_ERROR_INFO(SIGFPE, "fixpoint divide exception", divide_exception,
373 FPE_INTDIV, get_check_address(regs))
374 DO_ERROR_INFO(SIGFPE, "fixpoint overflow exception", overflow_exception,
375 FPE_INTOVF, get_check_address(regs))
376 DO_ERROR_INFO(SIGFPE, "HFP overflow exception", hfp_overflow_exception,
377 FPE_FLTOVF, get_check_address(regs))
378 DO_ERROR_INFO(SIGFPE, "HFP underflow exception", hfp_underflow_exception,
379 FPE_FLTUND, get_check_address(regs))
380 DO_ERROR_INFO(SIGFPE, "HFP significance exception", hfp_significance_exception,
381 FPE_FLTRES, get_check_address(regs))
382 DO_ERROR_INFO(SIGFPE, "HFP divide exception", hfp_divide_exception,
383 FPE_FLTDIV, get_check_address(regs))
384 DO_ERROR_INFO(SIGFPE, "HFP square root exception", hfp_sqrt_exception,
385 FPE_FLTINV, get_check_address(regs))
386 DO_ERROR_INFO(SIGILL, "operand exception", operand_exception,
387 ILL_ILLOPN, get_check_address(regs))
388 DO_ERROR_INFO(SIGILL, "privileged operation", privileged_op,
389 ILL_PRVOPC, get_check_address(regs))
390 DO_ERROR_INFO(SIGILL, "special operation exception", special_op_exception,
391 ILL_ILLOPN, get_check_address(regs))
392 DO_ERROR_INFO(SIGILL, "translation exception", translation_exception,
393 ILL_ILLOPN, get_check_address(regs))
396 do_fp_trap(struct pt_regs *regs, void *location,
397 int fpc, long interruption_code)
401 si.si_signo = SIGFPE;
403 si.si_addr = location;
405 /* FPC[2] is Data Exception Code */
406 if ((fpc & 0x00000300) == 0) {
407 /* bits 6 and 7 of DXC are 0 iff IEEE exception */
408 if (fpc & 0x8000) /* invalid fp operation */
409 si.si_code = FPE_FLTINV;
410 else if (fpc & 0x4000) /* div by 0 */
411 si.si_code = FPE_FLTDIV;
412 else if (fpc & 0x2000) /* overflow */
413 si.si_code = FPE_FLTOVF;
414 else if (fpc & 0x1000) /* underflow */
415 si.si_code = FPE_FLTUND;
416 else if (fpc & 0x0800) /* inexact */
417 si.si_code = FPE_FLTRES;
419 current->thread.ieee_instruction_pointer = (addr_t) location;
420 do_trap(interruption_code, SIGFPE,
421 "floating point exception", regs, &si);
424 asmlinkage void illegal_op(struct pt_regs * regs, long interruption_code)
431 location = (__u16 *) get_check_address(regs);
434 * We got all needed information from the lowcore and can
435 * now safely switch on interrupts.
437 if (regs->psw.mask & PSW_MASK_PSTATE)
440 if (regs->psw.mask & PSW_MASK_PSTATE) {
441 get_user(*((__u16 *) opcode), (__u16 __user *) location);
442 if (*((__u16 *) opcode) == S390_BREAKPOINT_U16) {
443 if (current->ptrace & PT_PTRACED)
444 force_sig(SIGTRAP, current);
447 #ifdef CONFIG_MATHEMU
448 } else if (opcode[0] == 0xb3) {
449 get_user(*((__u16 *) (opcode+2)), location+1);
450 signal = math_emu_b3(opcode, regs);
451 } else if (opcode[0] == 0xed) {
452 get_user(*((__u32 *) (opcode+2)),
453 (__u32 *)(location+1));
454 signal = math_emu_ed(opcode, regs);
455 } else if (*((__u16 *) opcode) == 0xb299) {
456 get_user(*((__u16 *) (opcode+2)), location+1);
457 signal = math_emu_srnm(opcode, regs);
458 } else if (*((__u16 *) opcode) == 0xb29c) {
459 get_user(*((__u16 *) (opcode+2)), location+1);
460 signal = math_emu_stfpc(opcode, regs);
461 } else if (*((__u16 *) opcode) == 0xb29d) {
462 get_user(*((__u16 *) (opcode+2)), location+1);
463 signal = math_emu_lfpc(opcode, regs);
470 #ifdef CONFIG_MATHEMU
471 if (signal == SIGFPE)
472 do_fp_trap(regs, location,
473 current->thread.fp_regs.fpc, interruption_code);
474 else if (signal == SIGSEGV) {
475 info.si_signo = signal;
477 info.si_code = SEGV_MAPERR;
478 info.si_addr = (void *) location;
479 do_trap(interruption_code, signal,
480 "user address fault", regs, &info);
484 info.si_signo = signal;
486 info.si_code = ILL_ILLOPC;
487 info.si_addr = (void __user *) location;
488 do_trap(interruption_code, signal,
489 "illegal operation", regs, &info);
494 #ifdef CONFIG_MATHEMU
496 specification_exception(struct pt_regs * regs, long interruption_code)
499 __u16 *location = NULL;
502 location = (__u16 *) get_check_address(regs);
505 * We got all needed information from the lowcore and can
506 * now safely switch on interrupts.
508 if (regs->psw.mask & PSW_MASK_PSTATE)
511 if (regs->psw.mask & PSW_MASK_PSTATE) {
512 get_user(*((__u16 *) opcode), location);
514 case 0x28: /* LDR Rx,Ry */
515 signal = math_emu_ldr(opcode);
517 case 0x38: /* LER Rx,Ry */
518 signal = math_emu_ler(opcode);
520 case 0x60: /* STD R,D(X,B) */
521 get_user(*((__u16 *) (opcode+2)), location+1);
522 signal = math_emu_std(opcode, regs);
524 case 0x68: /* LD R,D(X,B) */
525 get_user(*((__u16 *) (opcode+2)), location+1);
526 signal = math_emu_ld(opcode, regs);
528 case 0x70: /* STE R,D(X,B) */
529 get_user(*((__u16 *) (opcode+2)), location+1);
530 signal = math_emu_ste(opcode, regs);
532 case 0x78: /* LE R,D(X,B) */
533 get_user(*((__u16 *) (opcode+2)), location+1);
534 signal = math_emu_le(opcode, regs);
543 if (signal == SIGFPE)
544 do_fp_trap(regs, location,
545 current->thread.fp_regs.fpc, interruption_code);
548 info.si_signo = signal;
550 info.si_code = ILL_ILLOPN;
551 info.si_addr = location;
552 do_trap(interruption_code, signal,
553 "specification exception", regs, &info);
557 DO_ERROR_INFO(SIGILL, "specification exception", specification_exception,
558 ILL_ILLOPN, get_check_address(regs));
561 asmlinkage void data_exception(struct pt_regs * regs, long interruption_code)
566 location = (__u16 *) get_check_address(regs);
569 * We got all needed information from the lowcore and can
570 * now safely switch on interrupts.
572 if (regs->psw.mask & PSW_MASK_PSTATE)
575 if (MACHINE_HAS_IEEE)
576 __asm__ volatile ("stfpc %0\n\t"
577 : "=m" (current->thread.fp_regs.fpc));
579 #ifdef CONFIG_MATHEMU
580 else if (regs->psw.mask & PSW_MASK_PSTATE) {
582 get_user(*((__u16 *) opcode), location);
584 case 0x28: /* LDR Rx,Ry */
585 signal = math_emu_ldr(opcode);
587 case 0x38: /* LER Rx,Ry */
588 signal = math_emu_ler(opcode);
590 case 0x60: /* STD R,D(X,B) */
591 get_user(*((__u16 *) (opcode+2)), location+1);
592 signal = math_emu_std(opcode, regs);
594 case 0x68: /* LD R,D(X,B) */
595 get_user(*((__u16 *) (opcode+2)), location+1);
596 signal = math_emu_ld(opcode, regs);
598 case 0x70: /* STE R,D(X,B) */
599 get_user(*((__u16 *) (opcode+2)), location+1);
600 signal = math_emu_ste(opcode, regs);
602 case 0x78: /* LE R,D(X,B) */
603 get_user(*((__u16 *) (opcode+2)), location+1);
604 signal = math_emu_le(opcode, regs);
607 get_user(*((__u16 *) (opcode+2)), location+1);
608 signal = math_emu_b3(opcode, regs);
611 get_user(*((__u32 *) (opcode+2)),
612 (__u32 *)(location+1));
613 signal = math_emu_ed(opcode, regs);
616 if (opcode[1] == 0x99) {
617 get_user(*((__u16 *) (opcode+2)), location+1);
618 signal = math_emu_srnm(opcode, regs);
619 } else if (opcode[1] == 0x9c) {
620 get_user(*((__u16 *) (opcode+2)), location+1);
621 signal = math_emu_stfpc(opcode, regs);
622 } else if (opcode[1] == 0x9d) {
623 get_user(*((__u16 *) (opcode+2)), location+1);
624 signal = math_emu_lfpc(opcode, regs);
634 if (current->thread.fp_regs.fpc & FPC_DXC_MASK)
638 if (signal == SIGFPE)
639 do_fp_trap(regs, location,
640 current->thread.fp_regs.fpc, interruption_code);
643 info.si_signo = signal;
645 info.si_code = ILL_ILLOPN;
646 info.si_addr = location;
647 do_trap(interruption_code, signal,
648 "data exception", regs, &info);
652 asmlinkage void space_switch_exception(struct pt_regs * regs, long int_code)
656 /* Set user psw back to home space mode. */
657 if (regs->psw.mask & PSW_MASK_PSTATE)
658 regs->psw.mask |= PSW_ASC_HOME;
660 info.si_signo = SIGILL;
662 info.si_code = ILL_PRVOPC;
663 info.si_addr = get_check_address(regs);
664 do_trap(int_code, SIGILL, "space switch event", regs, &info);
667 asmlinkage void kernel_stack_overflow(struct pt_regs * regs)
670 printk("Kernel stack overflow.\n");
673 panic("Corrupt kernel stack, can't continue.");
676 /* init is done in lowcore.S and head.S */
678 void __init trap_init(void)
682 for (i = 0; i < 128; i++)
683 pgm_check_table[i] = &default_trap_handler;
684 pgm_check_table[1] = &illegal_op;
685 pgm_check_table[2] = &privileged_op;
686 pgm_check_table[3] = &execute_exception;
687 pgm_check_table[4] = &do_protection_exception;
688 pgm_check_table[5] = &addressing_exception;
689 pgm_check_table[6] = &specification_exception;
690 pgm_check_table[7] = &data_exception;
691 pgm_check_table[8] = &overflow_exception;
692 pgm_check_table[9] = ÷_exception;
693 pgm_check_table[0x0A] = &overflow_exception;
694 pgm_check_table[0x0B] = ÷_exception;
695 pgm_check_table[0x0C] = &hfp_overflow_exception;
696 pgm_check_table[0x0D] = &hfp_underflow_exception;
697 pgm_check_table[0x0E] = &hfp_significance_exception;
698 pgm_check_table[0x0F] = &hfp_divide_exception;
699 pgm_check_table[0x10] = &do_dat_exception;
700 pgm_check_table[0x11] = &do_dat_exception;
701 pgm_check_table[0x12] = &translation_exception;
702 pgm_check_table[0x13] = &special_op_exception;
704 pgm_check_table[0x38] = &do_dat_exception;
705 pgm_check_table[0x39] = &do_dat_exception;
706 pgm_check_table[0x3A] = &do_dat_exception;
707 pgm_check_table[0x3B] = &do_dat_exception;
708 #endif /* CONFIG_64BIT */
709 pgm_check_table[0x15] = &operand_exception;
710 pgm_check_table[0x1C] = &space_switch_exception;
711 pgm_check_table[0x1D] = &hfp_sqrt_exception;
712 pgm_check_table[0x40] = &do_monitor_call;
717 * Try to get pfault pseudo page faults going.
719 if (register_early_external_interrupt(0x2603, pfault_interrupt,
720 &ext_int_pfault) != 0)
721 panic("Couldn't request external interrupt 0x2603");
723 if (pfault_init() == 0)
726 /* Tough luck, no pfault. */
727 unregister_early_external_interrupt(0x2603, pfault_interrupt,