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>
33 #include <asm/system.h>
34 #include <asm/uaccess.h>
36 #include <asm/atomic.h>
37 #include <asm/mathemu.h>
38 #include <asm/cpcmd.h>
39 #include <asm/s390_ext.h>
40 #include <asm/lowcore.h>
41 #include <asm/debug.h>
43 /* Called from entry.S only */
44 extern void handle_per_exception(struct pt_regs *regs);
46 typedef void pgm_check_handler_t(struct pt_regs *, long);
47 pgm_check_handler_t *pgm_check_table[128];
50 #ifdef CONFIG_PROCESS_DEBUG
51 int sysctl_userprocess_debug = 1;
53 int sysctl_userprocess_debug = 0;
57 extern pgm_check_handler_t do_protection_exception;
58 extern pgm_check_handler_t do_dat_exception;
59 extern pgm_check_handler_t do_pseudo_page_fault;
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; })
70 #ifndef CONFIG_ARCH_S390X
71 #define FOURLONG "%08lx %08lx %08lx %08lx\n"
72 static int kstack_depth_to_print = 12;
73 #else /* CONFIG_ARCH_S390X */
74 #define FOURLONG "%016lx %016lx %016lx %016lx\n"
75 static int kstack_depth_to_print = 20;
76 #endif /* CONFIG_ARCH_S390X */
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->thread_info,
140 (unsigned long) task->thread_info + 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;
153 // debugging aid: "show_stack(NULL);" prints the
154 // back trace for this cpu.
157 sp = task ? (unsigned long *) task->thread.ksp : __r15;
160 for (i = 0; i < kstack_depth_to_print; i++) {
161 if (((addr_t) stack & (THREAD_SIZE-1)) == 0)
163 if (i && ((i * sizeof (long) % 32) == 0))
165 printk("%p ", (void *)*stack++);
168 show_trace(task, sp);
172 * The architecture-independent dump_stack generator
174 void dump_stack(void)
179 EXPORT_SYMBOL(dump_stack);
181 void show_registers(struct pt_regs *regs)
187 mode = (regs->psw.mask & PSW_MASK_PSTATE) ? "User" : "Krnl";
188 printk("%s PSW : %p %p",
189 mode, (void *) regs->psw.mask,
190 (void *) regs->psw.addr);
191 print_symbol(" (%s)\n", regs->psw.addr & PSW_ADDR_INSN);
192 printk("%s GPRS: " FOURLONG, mode,
193 regs->gprs[0], regs->gprs[1], regs->gprs[2], regs->gprs[3]);
195 regs->gprs[4], regs->gprs[5], regs->gprs[6], regs->gprs[7]);
197 regs->gprs[8], regs->gprs[9], regs->gprs[10], regs->gprs[11]);
199 regs->gprs[12], regs->gprs[13], regs->gprs[14], regs->gprs[15]);
202 /* FIXME: this isn't needed any more but it changes the ksymoops
203 * input. To remove or not to remove ... */
204 save_access_regs(regs->acrs);
205 printk("%s ACRS: %08x %08x %08x %08x\n", mode,
206 regs->acrs[0], regs->acrs[1], regs->acrs[2], regs->acrs[3]);
207 printk(" %08x %08x %08x %08x\n",
208 regs->acrs[4], regs->acrs[5], regs->acrs[6], regs->acrs[7]);
209 printk(" %08x %08x %08x %08x\n",
210 regs->acrs[8], regs->acrs[9], regs->acrs[10], regs->acrs[11]);
211 printk(" %08x %08x %08x %08x\n",
212 regs->acrs[12], regs->acrs[13], regs->acrs[14], regs->acrs[15]);
216 * Print the first 20 byte of the instruction stream at the
220 if (regs->psw.mask & PSW_MASK_PSTATE)
224 printk("%s Code: ", mode);
225 for (i = 0; i < 20; i++) {
227 if (__get_user(c, (char __user *)(regs->psw.addr + i))) {
238 /* This is called from fs/proc/array.c */
239 char *task_show_regs(struct task_struct *task, char *buffer)
241 struct pt_regs *regs;
243 regs = __KSTK_PTREGS(task);
244 buffer += sprintf(buffer, "task: %p, ksp: %p\n",
245 task, (void *)task->thread.ksp);
246 buffer += sprintf(buffer, "User PSW : %p %p\n",
247 (void *) regs->psw.mask, (void *)regs->psw.addr);
249 buffer += sprintf(buffer, "User GPRS: " FOURLONG,
250 regs->gprs[0], regs->gprs[1],
251 regs->gprs[2], regs->gprs[3]);
252 buffer += sprintf(buffer, " " FOURLONG,
253 regs->gprs[4], regs->gprs[5],
254 regs->gprs[6], regs->gprs[7]);
255 buffer += sprintf(buffer, " " FOURLONG,
256 regs->gprs[8], regs->gprs[9],
257 regs->gprs[10], regs->gprs[11]);
258 buffer += sprintf(buffer, " " FOURLONG,
259 regs->gprs[12], regs->gprs[13],
260 regs->gprs[14], regs->gprs[15]);
261 buffer += sprintf(buffer, "User ACRS: %08x %08x %08x %08x\n",
262 task->thread.acrs[0], task->thread.acrs[1],
263 task->thread.acrs[2], task->thread.acrs[3]);
264 buffer += sprintf(buffer, " %08x %08x %08x %08x\n",
265 task->thread.acrs[4], task->thread.acrs[5],
266 task->thread.acrs[6], task->thread.acrs[7]);
267 buffer += sprintf(buffer, " %08x %08x %08x %08x\n",
268 task->thread.acrs[8], task->thread.acrs[9],
269 task->thread.acrs[10], task->thread.acrs[11]);
270 buffer += sprintf(buffer, " %08x %08x %08x %08x\n",
271 task->thread.acrs[12], task->thread.acrs[13],
272 task->thread.acrs[14], task->thread.acrs[15]);
276 spinlock_t die_lock = SPIN_LOCK_UNLOCKED;
278 void die(const char * str, struct pt_regs * regs, long err)
280 static int die_counter;
284 spin_lock_irq(&die_lock);
286 printk("%s: %04lx [#%d]\n", str, err & 0xffff, ++die_counter);
290 spin_unlock_irq(&die_lock);
292 panic("Fatal exception in interrupt");
296 panic("Fatal exception: panic_on_oops");
302 report_user_fault(long interruption_code, struct pt_regs *regs)
304 #if defined(CONFIG_SYSCTL)
305 if (!sysctl_userprocess_debug)
308 #if defined(CONFIG_SYSCTL) || defined(CONFIG_PROCESS_DEBUG)
309 printk("User process fault: interruption code 0x%lX\n",
315 static void inline do_trap(long interruption_code, int signr, char *str,
316 struct pt_regs *regs, siginfo_t *info)
319 * We got all needed information from the lowcore and can
320 * now safely switch on interrupts.
322 if (regs->psw.mask & PSW_MASK_PSTATE)
325 if (regs->psw.mask & PSW_MASK_PSTATE) {
326 struct task_struct *tsk = current;
328 tsk->thread.trap_no = interruption_code & 0xffff;
329 force_sig_info(signr, info, tsk);
330 report_user_fault(interruption_code, regs);
332 const struct exception_table_entry *fixup;
333 fixup = search_exception_tables(regs->psw.addr & PSW_ADDR_INSN);
335 regs->psw.addr = fixup->fixup | PSW_ADDR_AMODE;
337 die(str, regs, interruption_code);
341 static inline void *get_check_address(struct pt_regs *regs)
343 return (void *)((regs->psw.addr-S390_lowcore.pgm_ilc) & PSW_ADDR_INSN);
346 void do_single_step(struct pt_regs *regs)
348 if ((current->ptrace & PT_PTRACED) != 0)
349 force_sig(SIGTRAP, current);
353 default_trap_handler(struct pt_regs * regs, long interruption_code)
355 if (regs->psw.mask & PSW_MASK_PSTATE) {
358 report_user_fault(interruption_code, regs);
360 die("Unknown program exception", regs, interruption_code);
363 #define DO_ERROR_INFO(signr, str, name, sicode, siaddr) \
364 asmlinkage void name(struct pt_regs * regs, long interruption_code) \
367 info.si_signo = signr; \
369 info.si_code = sicode; \
370 info.si_addr = (void *)siaddr; \
371 do_trap(interruption_code, signr, str, regs, &info); \
374 DO_ERROR_INFO(SIGILL, "addressing exception", addressing_exception,
375 ILL_ILLADR, get_check_address(regs))
376 DO_ERROR_INFO(SIGILL, "execute exception", execute_exception,
377 ILL_ILLOPN, get_check_address(regs))
378 DO_ERROR_INFO(SIGFPE, "fixpoint divide exception", divide_exception,
379 FPE_INTDIV, get_check_address(regs))
380 DO_ERROR_INFO(SIGFPE, "fixpoint overflow exception", overflow_exception,
381 FPE_INTOVF, get_check_address(regs))
382 DO_ERROR_INFO(SIGFPE, "HFP overflow exception", hfp_overflow_exception,
383 FPE_FLTOVF, get_check_address(regs))
384 DO_ERROR_INFO(SIGFPE, "HFP underflow exception", hfp_underflow_exception,
385 FPE_FLTUND, get_check_address(regs))
386 DO_ERROR_INFO(SIGFPE, "HFP significance exception", hfp_significance_exception,
387 FPE_FLTRES, get_check_address(regs))
388 DO_ERROR_INFO(SIGFPE, "HFP divide exception", hfp_divide_exception,
389 FPE_FLTDIV, get_check_address(regs))
390 DO_ERROR_INFO(SIGFPE, "HFP square root exception", hfp_sqrt_exception,
391 FPE_FLTINV, get_check_address(regs))
392 DO_ERROR_INFO(SIGILL, "operand exception", operand_exception,
393 ILL_ILLOPN, get_check_address(regs))
394 DO_ERROR_INFO(SIGILL, "privileged operation", privileged_op,
395 ILL_PRVOPC, get_check_address(regs))
396 DO_ERROR_INFO(SIGILL, "special operation exception", special_op_exception,
397 ILL_ILLOPN, get_check_address(regs))
398 DO_ERROR_INFO(SIGILL, "translation exception", translation_exception,
399 ILL_ILLOPN, get_check_address(regs))
402 do_fp_trap(struct pt_regs *regs, void *location,
403 int fpc, long interruption_code)
407 si.si_signo = SIGFPE;
409 si.si_addr = location;
411 /* FPC[2] is Data Exception Code */
412 if ((fpc & 0x00000300) == 0) {
413 /* bits 6 and 7 of DXC are 0 iff IEEE exception */
414 if (fpc & 0x8000) /* invalid fp operation */
415 si.si_code = FPE_FLTINV;
416 else if (fpc & 0x4000) /* div by 0 */
417 si.si_code = FPE_FLTDIV;
418 else if (fpc & 0x2000) /* overflow */
419 si.si_code = FPE_FLTOVF;
420 else if (fpc & 0x1000) /* underflow */
421 si.si_code = FPE_FLTUND;
422 else if (fpc & 0x0800) /* inexact */
423 si.si_code = FPE_FLTRES;
425 current->thread.ieee_instruction_pointer = (addr_t) location;
426 do_trap(interruption_code, SIGFPE,
427 "floating point exception", regs, &si);
430 asmlinkage void illegal_op(struct pt_regs * regs, long interruption_code)
437 location = (__u16 *) get_check_address(regs);
440 * We got all needed information from the lowcore and can
441 * now safely switch on interrupts.
443 if (regs->psw.mask & PSW_MASK_PSTATE)
446 if (regs->psw.mask & PSW_MASK_PSTATE) {
447 get_user(*((__u16 *) opcode), (__u16 __user *) location);
448 if (*((__u16 *) opcode) == S390_BREAKPOINT_U16) {
449 if (current->ptrace & PT_PTRACED)
450 force_sig(SIGTRAP, current);
453 #ifdef CONFIG_MATHEMU
454 } else if (opcode[0] == 0xb3) {
455 get_user(*((__u16 *) (opcode+2)), location+1);
456 signal = math_emu_b3(opcode, regs);
457 } else if (opcode[0] == 0xed) {
458 get_user(*((__u32 *) (opcode+2)),
459 (__u32 *)(location+1));
460 signal = math_emu_ed(opcode, regs);
461 } else if (*((__u16 *) opcode) == 0xb299) {
462 get_user(*((__u16 *) (opcode+2)), location+1);
463 signal = math_emu_srnm(opcode, regs);
464 } else if (*((__u16 *) opcode) == 0xb29c) {
465 get_user(*((__u16 *) (opcode+2)), location+1);
466 signal = math_emu_stfpc(opcode, regs);
467 } else if (*((__u16 *) opcode) == 0xb29d) {
468 get_user(*((__u16 *) (opcode+2)), location+1);
469 signal = math_emu_lfpc(opcode, regs);
476 #ifdef CONFIG_MATHEMU
477 if (signal == SIGFPE)
478 do_fp_trap(regs, location,
479 current->thread.fp_regs.fpc, interruption_code);
480 else if (signal == SIGSEGV) {
481 info.si_signo = signal;
483 info.si_code = SEGV_MAPERR;
484 info.si_addr = (void *) location;
485 do_trap(interruption_code, signal,
486 "user address fault", regs, &info);
490 info.si_signo = signal;
492 info.si_code = ILL_ILLOPC;
493 info.si_addr = (void *) location;
494 do_trap(interruption_code, signal,
495 "illegal operation", regs, &info);
500 #ifdef CONFIG_MATHEMU
502 specification_exception(struct pt_regs * regs, long interruption_code)
505 __u16 *location = NULL;
508 location = (__u16 *) get_check_address(regs);
511 * We got all needed information from the lowcore and can
512 * now safely switch on interrupts.
514 if (regs->psw.mask & PSW_MASK_PSTATE)
517 if (regs->psw.mask & PSW_MASK_PSTATE) {
518 get_user(*((__u16 *) opcode), location);
520 case 0x28: /* LDR Rx,Ry */
521 signal = math_emu_ldr(opcode);
523 case 0x38: /* LER Rx,Ry */
524 signal = math_emu_ler(opcode);
526 case 0x60: /* STD R,D(X,B) */
527 get_user(*((__u16 *) (opcode+2)), location+1);
528 signal = math_emu_std(opcode, regs);
530 case 0x68: /* LD R,D(X,B) */
531 get_user(*((__u16 *) (opcode+2)), location+1);
532 signal = math_emu_ld(opcode, regs);
534 case 0x70: /* STE R,D(X,B) */
535 get_user(*((__u16 *) (opcode+2)), location+1);
536 signal = math_emu_ste(opcode, regs);
538 case 0x78: /* LE R,D(X,B) */
539 get_user(*((__u16 *) (opcode+2)), location+1);
540 signal = math_emu_le(opcode, regs);
549 if (signal == SIGFPE)
550 do_fp_trap(regs, location,
551 current->thread.fp_regs.fpc, interruption_code);
554 info.si_signo = signal;
556 info.si_code = ILL_ILLOPN;
557 info.si_addr = location;
558 do_trap(interruption_code, signal,
559 "specification exception", regs, &info);
563 DO_ERROR_INFO(SIGILL, "specification exception", specification_exception,
564 ILL_ILLOPN, get_check_address(regs));
567 asmlinkage void data_exception(struct pt_regs * regs, long interruption_code)
572 location = (__u16 *) get_check_address(regs);
575 * We got all needed information from the lowcore and can
576 * now safely switch on interrupts.
578 if (regs->psw.mask & PSW_MASK_PSTATE)
581 if (MACHINE_HAS_IEEE)
582 __asm__ volatile ("stfpc %0\n\t"
583 : "=m" (current->thread.fp_regs.fpc));
585 #ifdef CONFIG_MATHEMU
586 else if (regs->psw.mask & PSW_MASK_PSTATE) {
588 get_user(*((__u16 *) opcode), location);
590 case 0x28: /* LDR Rx,Ry */
591 signal = math_emu_ldr(opcode);
593 case 0x38: /* LER Rx,Ry */
594 signal = math_emu_ler(opcode);
596 case 0x60: /* STD R,D(X,B) */
597 get_user(*((__u16 *) (opcode+2)), location+1);
598 signal = math_emu_std(opcode, regs);
600 case 0x68: /* LD R,D(X,B) */
601 get_user(*((__u16 *) (opcode+2)), location+1);
602 signal = math_emu_ld(opcode, regs);
604 case 0x70: /* STE R,D(X,B) */
605 get_user(*((__u16 *) (opcode+2)), location+1);
606 signal = math_emu_ste(opcode, regs);
608 case 0x78: /* LE R,D(X,B) */
609 get_user(*((__u16 *) (opcode+2)), location+1);
610 signal = math_emu_le(opcode, regs);
613 get_user(*((__u16 *) (opcode+2)), location+1);
614 signal = math_emu_b3(opcode, regs);
617 get_user(*((__u32 *) (opcode+2)),
618 (__u32 *)(location+1));
619 signal = math_emu_ed(opcode, regs);
622 if (opcode[1] == 0x99) {
623 get_user(*((__u16 *) (opcode+2)), location+1);
624 signal = math_emu_srnm(opcode, regs);
625 } else if (opcode[1] == 0x9c) {
626 get_user(*((__u16 *) (opcode+2)), location+1);
627 signal = math_emu_stfpc(opcode, regs);
628 } else if (opcode[1] == 0x9d) {
629 get_user(*((__u16 *) (opcode+2)), location+1);
630 signal = math_emu_lfpc(opcode, regs);
640 if (current->thread.fp_regs.fpc & FPC_DXC_MASK)
644 if (signal == SIGFPE)
645 do_fp_trap(regs, location,
646 current->thread.fp_regs.fpc, interruption_code);
649 info.si_signo = signal;
651 info.si_code = ILL_ILLOPN;
652 info.si_addr = location;
653 do_trap(interruption_code, signal,
654 "data exception", regs, &info);
658 asmlinkage void space_switch_exception(struct pt_regs * regs, long int_code)
662 /* Set user psw back to home space mode. */
663 if (regs->psw.mask & PSW_MASK_PSTATE)
664 regs->psw.mask |= PSW_ASC_HOME;
666 info.si_signo = SIGILL;
668 info.si_code = ILL_PRVOPC;
669 info.si_addr = get_check_address(regs);
670 do_trap(int_code, SIGILL, "space switch event", regs, &info);
673 asmlinkage void kernel_stack_overflow(struct pt_regs * regs)
675 die("Kernel stack overflow", regs, 0);
676 panic("Corrupt kernel stack, can't continue.");
680 /* init is done in lowcore.S and head.S */
682 void __init trap_init(void)
686 for (i = 0; i < 128; i++)
687 pgm_check_table[i] = &default_trap_handler;
688 pgm_check_table[1] = &illegal_op;
689 pgm_check_table[2] = &privileged_op;
690 pgm_check_table[3] = &execute_exception;
691 pgm_check_table[4] = &do_protection_exception;
692 pgm_check_table[5] = &addressing_exception;
693 pgm_check_table[6] = &specification_exception;
694 pgm_check_table[7] = &data_exception;
695 pgm_check_table[8] = &overflow_exception;
696 pgm_check_table[9] = ÷_exception;
697 pgm_check_table[0x0A] = &overflow_exception;
698 pgm_check_table[0x0B] = ÷_exception;
699 pgm_check_table[0x0C] = &hfp_overflow_exception;
700 pgm_check_table[0x0D] = &hfp_underflow_exception;
701 pgm_check_table[0x0E] = &hfp_significance_exception;
702 pgm_check_table[0x0F] = &hfp_divide_exception;
703 pgm_check_table[0x10] = &do_dat_exception;
704 pgm_check_table[0x11] = &do_dat_exception;
705 pgm_check_table[0x12] = &translation_exception;
706 pgm_check_table[0x13] = &special_op_exception;
707 #ifndef CONFIG_ARCH_S390X
708 pgm_check_table[0x14] = &do_pseudo_page_fault;
709 #else /* CONFIG_ARCH_S390X */
710 pgm_check_table[0x38] = &do_dat_exception;
711 pgm_check_table[0x39] = &do_dat_exception;
712 pgm_check_table[0x3A] = &do_dat_exception;
713 pgm_check_table[0x3B] = &do_dat_exception;
714 #endif /* CONFIG_ARCH_S390X */
715 pgm_check_table[0x15] = &operand_exception;
716 pgm_check_table[0x1C] = &space_switch_exception;
717 pgm_check_table[0x1D] = &hfp_sqrt_exception;
718 pgm_check_table[0x40] = &do_monitor_call;
722 * First try to get pfault pseudo page faults going.
723 * If this isn't available turn on pagex page faults.
726 /* request the 0x2603 external interrupt */
727 if (register_early_external_interrupt(0x2603, pfault_interrupt,
728 &ext_int_pfault) != 0)
729 panic("Couldn't request external interrupt 0x2603");
731 if (pfault_init() == 0)
734 /* Tough luck, no pfault. */
735 unregister_early_external_interrupt(0x2603, pfault_interrupt,
738 #ifndef CONFIG_ARCH_S390X
739 cpcmd("SET PAGEX ON", NULL, 0);