/* * S390 version * Copyright IBM Corp. 1999, 2000 * 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 "entry.h" void (*pgm_check_table[128])(struct pt_regs *regs); int show_unhandled_signals = 1; #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 */ static inline void __user *get_trap_ip(struct pt_regs *regs) { #ifdef CONFIG_64BIT unsigned long address; if (regs->int_code & 0x200) address = *(unsigned long *)(current->thread.trap_tdb + 24); else address = regs->psw.addr; return (void __user *) ((address - (regs->int_code >> 16)) & PSW_ADDR_INSN); #else return (void __user *) ((regs->psw.addr - (regs->int_code >> 16)) & PSW_ADDR_INSN); #endif } /* * 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 * sizeof(long) % 32) == 0) printk("%s ", i == 0 ? "" : "\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 = user_mode(regs) ? "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_MASK_EA | PSW_MASK_BA)); #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 (!user_mode(regs)) show_trace(NULL, (unsigned long *) regs->gprs[15]); show_last_breaking_event(regs); } static DEFINE_SPINLOCK(die_lock); void die(struct pt_regs *regs, const char *str) { static int die_counter; oops_enter(); lgr_info_log(); debug_stop_all(); console_verbose(); spin_lock_irq(&die_lock); bust_spinlocks(1); printk("%s: %04x [#%d] ", str, regs->int_code & 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, 0, regs->int_code & 0xffff, 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 inline void report_user_fault(struct pt_regs *regs, 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%X ", regs->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 void __kprobes do_trap(struct pt_regs *regs, int si_signo, int si_code, char *str) { siginfo_t info; if (notify_die(DIE_TRAP, str, regs, 0, regs->int_code, si_signo) == NOTIFY_STOP) return; if (user_mode(regs)) { info.si_signo = si_signo; info.si_errno = 0; info.si_code = si_code; info.si_addr = get_trap_ip(regs); force_sig_info(si_signo, &info, current); report_user_fault(regs, si_signo); } 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(regs, str); } } } void __kprobes do_per_trap(struct pt_regs *regs) { siginfo_t info; if (notify_die(DIE_SSTEP, "sstep", regs, 0, 0, SIGTRAP) == NOTIFY_STOP) return; if (!current->ptrace) return; info.si_signo = SIGTRAP; info.si_errno = 0; info.si_code = TRAP_HWBKPT; info.si_addr = (void __force __user *) current->thread.per_event.address; force_sig_info(SIGTRAP, &info, current); } static void default_trap_handler(struct pt_regs *regs) { if (user_mode(regs)) { report_user_fault(regs, SIGSEGV); do_exit(SIGSEGV); } else die(regs, "Unknown program exception"); } #define DO_ERROR_INFO(name, signr, sicode, str) \ static void name(struct pt_regs *regs) \ { \ do_trap(regs, signr, sicode, str); \ } 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") #ifdef CONFIG_64BIT DO_ERROR_INFO(transaction_exception, SIGILL, ILL_ILLOPN, "transaction constraint exception") #endif static inline void do_fp_trap(struct pt_regs *regs, int fpc) { int 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_code = FPE_FLTINV; else if (fpc & 0x4000) /* div by 0 */ si_code = FPE_FLTDIV; else if (fpc & 0x2000) /* overflow */ si_code = FPE_FLTOVF; else if (fpc & 0x1000) /* underflow */ si_code = FPE_FLTUND; else if (fpc & 0x0800) /* inexact */ si_code = FPE_FLTRES; } do_trap(regs, SIGFPE, si_code, "floating point exception"); } static void __kprobes illegal_op(struct pt_regs *regs) { siginfo_t info; __u8 opcode[6]; __u16 __user *location; int signal = 0; location = get_trap_ip(regs); if (user_mode(regs)) { if (get_user(*((__u16 *) opcode), (__u16 __user *) location)) return; if (*((__u16 *) opcode) == S390_BREAKPOINT_U16) { if (current->ptrace) { info.si_signo = SIGTRAP; info.si_errno = 0; info.si_code = TRAP_BRKPT; info.si_addr = location; force_sig_info(SIGTRAP, &info, 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, 0, 3, SIGTRAP) != NOTIFY_STOP) signal = SIGILL; } #ifdef CONFIG_MATHEMU if (signal == SIGFPE) do_fp_trap(regs, current->thread.fp_regs.fpc); else if (signal == SIGSEGV) do_trap(regs, signal, SEGV_MAPERR, "user address fault"); else #endif if (signal) do_trap(regs, signal, ILL_ILLOPC, "illegal operation"); } #ifdef CONFIG_MATHEMU void specification_exception(struct pt_regs *regs) { __u8 opcode[6]; __u16 __user *location = NULL; int signal = 0; location = (__u16 __user *) get_trap_ip(regs); if (user_mode(regs)) { 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, current->thread.fp_regs.fpc); else if (signal) do_trap(regs, signal, ILL_ILLOPN, "specification exception"); } #else DO_ERROR_INFO(specification_exception, SIGILL, ILL_ILLOPN, "specification exception"); #endif static void data_exception(struct pt_regs *regs) { __u16 __user *location; int signal = 0; location = get_trap_ip(regs); if (MACHINE_HAS_IEEE) asm volatile("stfpc %0" : "=m" (current->thread.fp_regs.fpc)); #ifdef CONFIG_MATHEMU else if (user_mode(regs)) { __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, current->thread.fp_regs.fpc); else if (signal) do_trap(regs, signal, ILL_ILLOPN, "data exception"); } static void space_switch_exception(struct pt_regs *regs) { /* Set user psw back to home space mode. */ if (user_mode(regs)) regs->psw.mask |= PSW_ASC_HOME; /* Send SIGILL. */ do_trap(regs, SIGILL, ILL_PRVOPC, "space switch event"); } 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[0x18] = &transaction_exception; 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; /* Enable machine checks early. */ local_mcck_enable(); }