/* * arch/s390/kernel/traps.c * * S390 version * Copyright (C) 1999,2000 IBM Deutschland Entwicklung GmbH, IBM Corporation * Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com), * Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com), * * Derived from "arch/i386/kernel/traps.c" * Copyright (C) 1991, 1992 Linus Torvalds */ /* * 'Traps.c' handles hardware traps and faults after we have saved some * state in 'asm.s'. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "entry.h" pgm_check_handler_t *pgm_check_table[128]; int show_unhandled_signals; extern pgm_check_handler_t do_protection_exception; extern pgm_check_handler_t do_dat_exception; extern pgm_check_handler_t do_asce_exception; #define stack_pointer ({ void **sp; asm("la %0,0(15)" : "=&d" (sp)); sp; }) #ifndef CONFIG_64BIT #define LONG "%08lx " #define FOURLONG "%08lx %08lx %08lx %08lx\n" static int kstack_depth_to_print = 12; #else /* CONFIG_64BIT */ #define LONG "%016lx " #define FOURLONG "%016lx %016lx %016lx %016lx\n" static int kstack_depth_to_print = 20; #endif /* CONFIG_64BIT */ /* * For show_trace we have tree different stack to consider: * - the panic stack which is used if the kernel stack has overflown * - the asynchronous interrupt stack (cpu related) * - the synchronous kernel stack (process related) * The stack trace can start at any of the three stack and can potentially * touch all of them. The order is: panic stack, async stack, sync stack. */ static unsigned long __show_trace(unsigned long sp, unsigned long low, unsigned long high) { struct stack_frame *sf; struct pt_regs *regs; while (1) { sp = sp & PSW_ADDR_INSN; if (sp < low || sp > high - sizeof(*sf)) return sp; sf = (struct stack_frame *) sp; printk("([<%016lx>] ", sf->gprs[8] & PSW_ADDR_INSN); print_symbol("%s)\n", sf->gprs[8] & PSW_ADDR_INSN); /* Follow the backchain. */ while (1) { low = sp; sp = sf->back_chain & PSW_ADDR_INSN; if (!sp) break; if (sp <= low || sp > high - sizeof(*sf)) return sp; sf = (struct stack_frame *) sp; printk(" [<%016lx>] ", sf->gprs[8] & PSW_ADDR_INSN); print_symbol("%s\n", sf->gprs[8] & PSW_ADDR_INSN); } /* Zero backchain detected, check for interrupt frame. */ sp = (unsigned long) (sf + 1); if (sp <= low || sp > high - sizeof(*regs)) return sp; regs = (struct pt_regs *) sp; printk(" [<%016lx>] ", regs->psw.addr & PSW_ADDR_INSN); print_symbol("%s\n", regs->psw.addr & PSW_ADDR_INSN); low = sp; sp = regs->gprs[15]; } } static void show_trace(struct task_struct *task, unsigned long *stack) { register unsigned long __r15 asm ("15"); unsigned long sp; sp = (unsigned long) stack; if (!sp) sp = task ? task->thread.ksp : __r15; printk("Call Trace:\n"); #ifdef CONFIG_CHECK_STACK sp = __show_trace(sp, S390_lowcore.panic_stack - 4096, S390_lowcore.panic_stack); #endif sp = __show_trace(sp, S390_lowcore.async_stack - ASYNC_SIZE, S390_lowcore.async_stack); if (task) __show_trace(sp, (unsigned long) task_stack_page(task), (unsigned long) task_stack_page(task) + THREAD_SIZE); else __show_trace(sp, S390_lowcore.thread_info, S390_lowcore.thread_info + THREAD_SIZE); if (!task) task = current; debug_show_held_locks(task); } void show_stack(struct task_struct *task, unsigned long *sp) { register unsigned long * __r15 asm ("15"); unsigned long *stack; int i; if (!sp) stack = task ? (unsigned long *) task->thread.ksp : __r15; else stack = sp; for (i = 0; i < kstack_depth_to_print; i++) { if (((addr_t) stack & (THREAD_SIZE-1)) == 0) break; if (i && ((i * sizeof (long) % 32) == 0)) printk("\n "); printk(LONG, *stack++); } printk("\n"); show_trace(task, sp); } static void show_last_breaking_event(struct pt_regs *regs) { #ifdef CONFIG_64BIT printk("Last Breaking-Event-Address:\n"); printk(" [<%016lx>] ", regs->args[0] & PSW_ADDR_INSN); print_symbol("%s\n", regs->args[0] & PSW_ADDR_INSN); #endif } /* * The architecture-independent dump_stack generator */ void dump_stack(void) { printk("CPU: %d %s %s %.*s\n", task_thread_info(current)->cpu, print_tainted(), init_utsname()->release, (int)strcspn(init_utsname()->version, " "), init_utsname()->version); printk("Process %s (pid: %d, task: %p, ksp: %p)\n", current->comm, current->pid, current, (void *) current->thread.ksp); show_stack(NULL, NULL); } EXPORT_SYMBOL(dump_stack); static inline int mask_bits(struct pt_regs *regs, unsigned long bits) { return (regs->psw.mask & bits) / ((~bits + 1) & bits); } void show_registers(struct pt_regs *regs) { char *mode; mode = (regs->psw.mask & PSW_MASK_PSTATE) ? "User" : "Krnl"; printk("%s PSW : %p %p", mode, (void *) regs->psw.mask, (void *) regs->psw.addr); print_symbol(" (%s)\n", regs->psw.addr & PSW_ADDR_INSN); printk(" R:%x T:%x IO:%x EX:%x Key:%x M:%x W:%x " "P:%x AS:%x CC:%x PM:%x", mask_bits(regs, PSW_MASK_PER), mask_bits(regs, PSW_MASK_DAT), mask_bits(regs, PSW_MASK_IO), mask_bits(regs, PSW_MASK_EXT), mask_bits(regs, PSW_MASK_KEY), mask_bits(regs, PSW_MASK_MCHECK), mask_bits(regs, PSW_MASK_WAIT), mask_bits(regs, PSW_MASK_PSTATE), mask_bits(regs, PSW_MASK_ASC), mask_bits(regs, PSW_MASK_CC), mask_bits(regs, PSW_MASK_PM)); #ifdef CONFIG_64BIT printk(" EA:%x", mask_bits(regs, PSW_BASE_BITS)); #endif printk("\n%s GPRS: " FOURLONG, mode, regs->gprs[0], regs->gprs[1], regs->gprs[2], regs->gprs[3]); printk(" " FOURLONG, regs->gprs[4], regs->gprs[5], regs->gprs[6], regs->gprs[7]); printk(" " FOURLONG, regs->gprs[8], regs->gprs[9], regs->gprs[10], regs->gprs[11]); printk(" " FOURLONG, regs->gprs[12], regs->gprs[13], regs->gprs[14], regs->gprs[15]); show_code(regs); } void show_regs(struct pt_regs *regs) { print_modules(); printk("CPU: %d %s %s %.*s\n", task_thread_info(current)->cpu, print_tainted(), init_utsname()->release, (int)strcspn(init_utsname()->version, " "), init_utsname()->version); printk("Process %s (pid: %d, task: %p, ksp: %p)\n", current->comm, current->pid, current, (void *) current->thread.ksp); show_registers(regs); /* Show stack backtrace if pt_regs is from kernel mode */ if (!(regs->psw.mask & PSW_MASK_PSTATE)) show_trace(NULL, (unsigned long *) regs->gprs[15]); show_last_breaking_event(regs); } /* This is called from fs/proc/array.c */ void task_show_regs(struct seq_file *m, struct task_struct *task) { struct pt_regs *regs; regs = task_pt_regs(task); seq_printf(m, "task: %p, ksp: %p\n", task, (void *)task->thread.ksp); seq_printf(m, "User PSW : %p %p\n", (void *) regs->psw.mask, (void *)regs->psw.addr); seq_printf(m, "User GPRS: " FOURLONG, regs->gprs[0], regs->gprs[1], regs->gprs[2], regs->gprs[3]); seq_printf(m, " " FOURLONG, regs->gprs[4], regs->gprs[5], regs->gprs[6], regs->gprs[7]); seq_printf(m, " " FOURLONG, regs->gprs[8], regs->gprs[9], regs->gprs[10], regs->gprs[11]); seq_printf(m, " " FOURLONG, regs->gprs[12], regs->gprs[13], regs->gprs[14], regs->gprs[15]); seq_printf(m, "User ACRS: %08x %08x %08x %08x\n", task->thread.acrs[0], task->thread.acrs[1], task->thread.acrs[2], task->thread.acrs[3]); seq_printf(m, " %08x %08x %08x %08x\n", task->thread.acrs[4], task->thread.acrs[5], task->thread.acrs[6], task->thread.acrs[7]); seq_printf(m, " %08x %08x %08x %08x\n", task->thread.acrs[8], task->thread.acrs[9], task->thread.acrs[10], task->thread.acrs[11]); seq_printf(m, " %08x %08x %08x %08x\n", task->thread.acrs[12], task->thread.acrs[13], task->thread.acrs[14], task->thread.acrs[15]); } static DEFINE_SPINLOCK(die_lock); void die(const char * str, struct pt_regs * regs, long err) { static int die_counter; oops_enter(); debug_stop_all(); console_verbose(); spin_lock_irq(&die_lock); bust_spinlocks(1); printk("%s: %04lx [#%d] ", str, err & 0xffff, ++die_counter); #ifdef CONFIG_PREEMPT printk("PREEMPT "); #endif #ifdef CONFIG_SMP printk("SMP "); #endif #ifdef CONFIG_DEBUG_PAGEALLOC printk("DEBUG_PAGEALLOC"); #endif printk("\n"); notify_die(DIE_OOPS, str, regs, err, current->thread.trap_no, SIGSEGV); show_regs(regs); bust_spinlocks(0); add_taint(TAINT_DIE); spin_unlock_irq(&die_lock); if (in_interrupt()) panic("Fatal exception in interrupt"); if (panic_on_oops) panic("Fatal exception: panic_on_oops"); oops_exit(); do_exit(SIGSEGV); } static void inline report_user_fault(struct pt_regs *regs, long int_code, int signr) { if ((task_pid_nr(current) > 1) && !show_unhandled_signals) return; if (!unhandled_signal(current, signr)) return; if (!printk_ratelimit()) return; printk("User process fault: interruption code 0x%lX ", int_code); print_vma_addr("in ", regs->psw.addr & PSW_ADDR_INSN); printk("\n"); show_regs(regs); } int is_valid_bugaddr(unsigned long addr) { return 1; } static inline void __kprobes do_trap(long pgm_int_code, int signr, char *str, struct pt_regs *regs, siginfo_t *info) { if (notify_die(DIE_TRAP, str, regs, pgm_int_code, pgm_int_code, signr) == NOTIFY_STOP) return; if (regs->psw.mask & PSW_MASK_PSTATE) { struct task_struct *tsk = current; tsk->thread.trap_no = pgm_int_code & 0xffff; force_sig_info(signr, info, tsk); report_user_fault(regs, pgm_int_code, signr); } else { const struct exception_table_entry *fixup; fixup = search_exception_tables(regs->psw.addr & PSW_ADDR_INSN); if (fixup) regs->psw.addr = fixup->fixup | PSW_ADDR_AMODE; else { enum bug_trap_type btt; btt = report_bug(regs->psw.addr & PSW_ADDR_INSN, regs); if (btt == BUG_TRAP_TYPE_WARN) return; die(str, regs, pgm_int_code); } } } static inline void __user *get_psw_address(struct pt_regs *regs, long pgm_int_code) { return (void __user *) ((regs->psw.addr - (pgm_int_code >> 16)) & PSW_ADDR_INSN); } void __kprobes do_single_step(struct pt_regs *regs) { if (notify_die(DIE_SSTEP, "sstep", regs, 0, 0, SIGTRAP) == NOTIFY_STOP){ return; } if (tracehook_consider_fatal_signal(current, SIGTRAP)) force_sig(SIGTRAP, current); } static void default_trap_handler(struct pt_regs *regs, long pgm_int_code, unsigned long trans_exc_code) { if (regs->psw.mask & PSW_MASK_PSTATE) { report_user_fault(regs, pgm_int_code, SIGSEGV); do_exit(SIGSEGV); } else die("Unknown program exception", regs, pgm_int_code); } #define DO_ERROR_INFO(name, signr, sicode, str) \ static void name(struct pt_regs *regs, long pgm_int_code, \ unsigned long trans_exc_code) \ { \ siginfo_t info; \ info.si_signo = signr; \ info.si_errno = 0; \ info.si_code = sicode; \ info.si_addr = get_psw_address(regs, pgm_int_code); \ do_trap(pgm_int_code, signr, str, regs, &info); \ } DO_ERROR_INFO(addressing_exception, SIGILL, ILL_ILLADR, "addressing exception") DO_ERROR_INFO(execute_exception, SIGILL, ILL_ILLOPN, "execute exception") DO_ERROR_INFO(divide_exception, SIGFPE, FPE_INTDIV, "fixpoint divide exception") DO_ERROR_INFO(overflow_exception, SIGFPE, FPE_INTOVF, "fixpoint overflow exception") DO_ERROR_INFO(hfp_overflow_exception, SIGFPE, FPE_FLTOVF, "HFP overflow exception") DO_ERROR_INFO(hfp_underflow_exception, SIGFPE, FPE_FLTUND, "HFP underflow exception") DO_ERROR_INFO(hfp_significance_exception, SIGFPE, FPE_FLTRES, "HFP significance exception") DO_ERROR_INFO(hfp_divide_exception, SIGFPE, FPE_FLTDIV, "HFP divide exception") DO_ERROR_INFO(hfp_sqrt_exception, SIGFPE, FPE_FLTINV, "HFP square root exception") DO_ERROR_INFO(operand_exception, SIGILL, ILL_ILLOPN, "operand exception") DO_ERROR_INFO(privileged_op, SIGILL, ILL_PRVOPC, "privileged operation") DO_ERROR_INFO(special_op_exception, SIGILL, ILL_ILLOPN, "special operation exception") DO_ERROR_INFO(translation_exception, SIGILL, ILL_ILLOPN, "translation exception") static inline void do_fp_trap(struct pt_regs *regs, void __user *location, int fpc, long pgm_int_code) { siginfo_t si; si.si_signo = SIGFPE; si.si_errno = 0; si.si_addr = location; si.si_code = 0; /* FPC[2] is Data Exception Code */ if ((fpc & 0x00000300) == 0) { /* bits 6 and 7 of DXC are 0 iff IEEE exception */ if (fpc & 0x8000) /* invalid fp operation */ si.si_code = FPE_FLTINV; else if (fpc & 0x4000) /* div by 0 */ si.si_code = FPE_FLTDIV; else if (fpc & 0x2000) /* overflow */ si.si_code = FPE_FLTOVF; else if (fpc & 0x1000) /* underflow */ si.si_code = FPE_FLTUND; else if (fpc & 0x0800) /* inexact */ si.si_code = FPE_FLTRES; } do_trap(pgm_int_code, SIGFPE, "floating point exception", regs, &si); } static void __kprobes illegal_op(struct pt_regs *regs, long pgm_int_code, unsigned long trans_exc_code) { siginfo_t info; __u8 opcode[6]; __u16 __user *location; int signal = 0; location = get_psw_address(regs, pgm_int_code); if (regs->psw.mask & PSW_MASK_PSTATE) { if (get_user(*((__u16 *) opcode), (__u16 __user *) location)) return; if (*((__u16 *) opcode) == S390_BREAKPOINT_U16) { if (tracehook_consider_fatal_signal(current, SIGTRAP)) force_sig(SIGTRAP, current); else signal = SIGILL; #ifdef CONFIG_MATHEMU } else if (opcode[0] == 0xb3) { if (get_user(*((__u16 *) (opcode+2)), location+1)) return; signal = math_emu_b3(opcode, regs); } else if (opcode[0] == 0xed) { if (get_user(*((__u32 *) (opcode+2)), (__u32 __user *)(location+1))) return; signal = math_emu_ed(opcode, regs); } else if (*((__u16 *) opcode) == 0xb299) { if (get_user(*((__u16 *) (opcode+2)), location+1)) return; signal = math_emu_srnm(opcode, regs); } else if (*((__u16 *) opcode) == 0xb29c) { if (get_user(*((__u16 *) (opcode+2)), location+1)) return; signal = math_emu_stfpc(opcode, regs); } else if (*((__u16 *) opcode) == 0xb29d) { if (get_user(*((__u16 *) (opcode+2)), location+1)) return; signal = math_emu_lfpc(opcode, regs); #endif } else signal = SIGILL; } else { /* * If we get an illegal op in kernel mode, send it through the * kprobes notifier. If kprobes doesn't pick it up, SIGILL */ if (notify_die(DIE_BPT, "bpt", regs, pgm_int_code, 3, SIGTRAP) != NOTIFY_STOP) signal = SIGILL; } #ifdef CONFIG_MATHEMU if (signal == SIGFPE) do_fp_trap(regs, location, current->thread.fp_regs.fpc, pgm_int_code); else if (signal == SIGSEGV) { info.si_signo = signal; info.si_errno = 0; info.si_code = SEGV_MAPERR; info.si_addr = (void __user *) location; do_trap(pgm_int_code, signal, "user address fault", regs, &info); } else #endif if (signal) { info.si_signo = signal; info.si_errno = 0; info.si_code = ILL_ILLOPC; info.si_addr = (void __user *) location; do_trap(pgm_int_code, signal, "illegal operation", regs, &info); } } #ifdef CONFIG_MATHEMU asmlinkage void specification_exception(struct pt_regs *regs, long pgm_int_code, unsigned long trans_exc_code) { __u8 opcode[6]; __u16 __user *location = NULL; int signal = 0; location = (__u16 __user *) get_psw_address(regs, pgm_int_code); if (regs->psw.mask & PSW_MASK_PSTATE) { get_user(*((__u16 *) opcode), location); switch (opcode[0]) { case 0x28: /* LDR Rx,Ry */ signal = math_emu_ldr(opcode); break; case 0x38: /* LER Rx,Ry */ signal = math_emu_ler(opcode); break; case 0x60: /* STD R,D(X,B) */ get_user(*((__u16 *) (opcode+2)), location+1); signal = math_emu_std(opcode, regs); break; case 0x68: /* LD R,D(X,B) */ get_user(*((__u16 *) (opcode+2)), location+1); signal = math_emu_ld(opcode, regs); break; case 0x70: /* STE R,D(X,B) */ get_user(*((__u16 *) (opcode+2)), location+1); signal = math_emu_ste(opcode, regs); break; case 0x78: /* LE R,D(X,B) */ get_user(*((__u16 *) (opcode+2)), location+1); signal = math_emu_le(opcode, regs); break; default: signal = SIGILL; break; } } else signal = SIGILL; if (signal == SIGFPE) do_fp_trap(regs, location, current->thread.fp_regs.fpc, pgm_int_code); else if (signal) { siginfo_t info; info.si_signo = signal; info.si_errno = 0; info.si_code = ILL_ILLOPN; info.si_addr = location; do_trap(pgm_int_code, signal, "specification exception", regs, &info); } } #else DO_ERROR_INFO(specification_exception, SIGILL, ILL_ILLOPN, "specification exception"); #endif static void data_exception(struct pt_regs *regs, long pgm_int_code, unsigned long trans_exc_code) { __u16 __user *location; int signal = 0; location = get_psw_address(regs, pgm_int_code); if (MACHINE_HAS_IEEE) asm volatile("stfpc %0" : "=m" (current->thread.fp_regs.fpc)); #ifdef CONFIG_MATHEMU else if (regs->psw.mask & PSW_MASK_PSTATE) { __u8 opcode[6]; get_user(*((__u16 *) opcode), location); switch (opcode[0]) { case 0x28: /* LDR Rx,Ry */ signal = math_emu_ldr(opcode); break; case 0x38: /* LER Rx,Ry */ signal = math_emu_ler(opcode); break; case 0x60: /* STD R,D(X,B) */ get_user(*((__u16 *) (opcode+2)), location+1); signal = math_emu_std(opcode, regs); break; case 0x68: /* LD R,D(X,B) */ get_user(*((__u16 *) (opcode+2)), location+1); signal = math_emu_ld(opcode, regs); break; case 0x70: /* STE R,D(X,B) */ get_user(*((__u16 *) (opcode+2)), location+1); signal = math_emu_ste(opcode, regs); break; case 0x78: /* LE R,D(X,B) */ get_user(*((__u16 *) (opcode+2)), location+1); signal = math_emu_le(opcode, regs); break; case 0xb3: get_user(*((__u16 *) (opcode+2)), location+1); signal = math_emu_b3(opcode, regs); break; case 0xed: get_user(*((__u32 *) (opcode+2)), (__u32 __user *)(location+1)); signal = math_emu_ed(opcode, regs); break; case 0xb2: if (opcode[1] == 0x99) { get_user(*((__u16 *) (opcode+2)), location+1); signal = math_emu_srnm(opcode, regs); } else if (opcode[1] == 0x9c) { get_user(*((__u16 *) (opcode+2)), location+1); signal = math_emu_stfpc(opcode, regs); } else if (opcode[1] == 0x9d) { get_user(*((__u16 *) (opcode+2)), location+1); signal = math_emu_lfpc(opcode, regs); } else signal = SIGILL; break; default: signal = SIGILL; break; } } #endif if (current->thread.fp_regs.fpc & FPC_DXC_MASK) signal = SIGFPE; else signal = SIGILL; if (signal == SIGFPE) do_fp_trap(regs, location, current->thread.fp_regs.fpc, pgm_int_code); else if (signal) { siginfo_t info; info.si_signo = signal; info.si_errno = 0; info.si_code = ILL_ILLOPN; info.si_addr = location; do_trap(pgm_int_code, signal, "data exception", regs, &info); } } static void space_switch_exception(struct pt_regs *regs, long pgm_int_code, unsigned long trans_exc_code) { siginfo_t info; /* Set user psw back to home space mode. */ if (regs->psw.mask & PSW_MASK_PSTATE) regs->psw.mask |= PSW_ASC_HOME; /* Send SIGILL. */ info.si_signo = SIGILL; info.si_errno = 0; info.si_code = ILL_PRVOPC; info.si_addr = get_psw_address(regs, pgm_int_code); do_trap(pgm_int_code, SIGILL, "space switch event", regs, &info); } asmlinkage void __kprobes kernel_stack_overflow(struct pt_regs * regs) { bust_spinlocks(1); printk("Kernel stack overflow.\n"); show_regs(regs); bust_spinlocks(0); panic("Corrupt kernel stack, can't continue."); } /* init is done in lowcore.S and head.S */ void __init trap_init(void) { int i; for (i = 0; i < 128; i++) pgm_check_table[i] = &default_trap_handler; pgm_check_table[1] = &illegal_op; pgm_check_table[2] = &privileged_op; pgm_check_table[3] = &execute_exception; pgm_check_table[4] = &do_protection_exception; pgm_check_table[5] = &addressing_exception; pgm_check_table[6] = &specification_exception; pgm_check_table[7] = &data_exception; pgm_check_table[8] = &overflow_exception; pgm_check_table[9] = ÷_exception; pgm_check_table[0x0A] = &overflow_exception; pgm_check_table[0x0B] = ÷_exception; pgm_check_table[0x0C] = &hfp_overflow_exception; pgm_check_table[0x0D] = &hfp_underflow_exception; pgm_check_table[0x0E] = &hfp_significance_exception; pgm_check_table[0x0F] = &hfp_divide_exception; pgm_check_table[0x10] = &do_dat_exception; pgm_check_table[0x11] = &do_dat_exception; pgm_check_table[0x12] = &translation_exception; pgm_check_table[0x13] = &special_op_exception; #ifdef CONFIG_64BIT pgm_check_table[0x38] = &do_asce_exception; pgm_check_table[0x39] = &do_dat_exception; pgm_check_table[0x3A] = &do_dat_exception; pgm_check_table[0x3B] = &do_dat_exception; #endif /* CONFIG_64BIT */ pgm_check_table[0x15] = &operand_exception; pgm_check_table[0x1C] = &space_switch_exception; pgm_check_table[0x1D] = &hfp_sqrt_exception; pfault_irq_init(); }