| /* |
| * linux/arch/arm/kernel/traps.c |
| * |
| * Copyright (C) 1995-2009 Russell King |
| * Fragments that appear the same as linux/arch/i386/kernel/traps.c (C) Linus Torvalds |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License version 2 as |
| * published by the Free Software Foundation. |
| * |
| * 'traps.c' handles hardware exceptions after we have saved some state in |
| * 'linux/arch/arm/lib/traps.S'. Mostly a debugging aid, but will probably |
| * kill the offending process. |
| */ |
| #include <linux/signal.h> |
| #include <linux/personality.h> |
| #include <linux/kallsyms.h> |
| #include <linux/spinlock.h> |
| #include <linux/uaccess.h> |
| #include <linux/hardirq.h> |
| #include <linux/kdebug.h> |
| #include <linux/kprobes.h> |
| #include <linux/module.h> |
| #include <linux/kexec.h> |
| #include <linux/bug.h> |
| #include <linux/delay.h> |
| #include <linux/init.h> |
| #include <linux/sched.h> |
| #include <linux/irq.h> |
| |
| #include <linux/atomic.h> |
| #include <asm/cacheflush.h> |
| #include <asm/exception.h> |
| #include <asm/unistd.h> |
| #include <asm/traps.h> |
| #include <asm/ptrace.h> |
| #include <asm/unwind.h> |
| #include <asm/tls.h> |
| #include <asm/system_misc.h> |
| #include <asm/opcodes.h> |
| |
| |
| static const char *handler[]= { |
| "prefetch abort", |
| "data abort", |
| "address exception", |
| "interrupt", |
| "undefined instruction", |
| }; |
| |
| void *vectors_page; |
| |
| #ifdef CONFIG_DEBUG_USER |
| unsigned int user_debug; |
| |
| static int __init user_debug_setup(char *str) |
| { |
| get_option(&str, &user_debug); |
| return 1; |
| } |
| __setup("user_debug=", user_debug_setup); |
| #endif |
| |
| static void dump_mem(const char *, const char *, unsigned long, unsigned long); |
| |
| void dump_backtrace_entry(unsigned long where, unsigned long from, unsigned long frame) |
| { |
| #ifdef CONFIG_KALLSYMS |
| printk("[<%08lx>] (%ps) from [<%08lx>] (%pS)\n", where, (void *)where, from, (void *)from); |
| #else |
| printk("Function entered at [<%08lx>] from [<%08lx>]\n", where, from); |
| #endif |
| |
| if (in_exception_text(where)) |
| dump_mem("", "Exception stack", frame + 4, frame + 4 + sizeof(struct pt_regs)); |
| } |
| |
| #ifndef CONFIG_ARM_UNWIND |
| /* |
| * Stack pointers should always be within the kernels view of |
| * physical memory. If it is not there, then we can't dump |
| * out any information relating to the stack. |
| */ |
| static int verify_stack(unsigned long sp) |
| { |
| if (sp < PAGE_OFFSET || |
| (sp > (unsigned long)high_memory && high_memory != NULL)) |
| return -EFAULT; |
| |
| return 0; |
| } |
| #endif |
| |
| /* |
| * Dump out the contents of some memory nicely... |
| */ |
| static void dump_mem(const char *lvl, const char *str, unsigned long bottom, |
| unsigned long top) |
| { |
| unsigned long first; |
| mm_segment_t fs; |
| int i; |
| |
| /* |
| * We need to switch to kernel mode so that we can use __get_user |
| * to safely read from kernel space. Note that we now dump the |
| * code first, just in case the backtrace kills us. |
| */ |
| fs = get_fs(); |
| set_fs(KERNEL_DS); |
| |
| printk("%s%s(0x%08lx to 0x%08lx)\n", lvl, str, bottom, top); |
| |
| for (first = bottom & ~31; first < top; first += 32) { |
| unsigned long p; |
| char str[sizeof(" 12345678") * 8 + 1]; |
| |
| memset(str, ' ', sizeof(str)); |
| str[sizeof(str) - 1] = '\0'; |
| |
| for (p = first, i = 0; i < 8 && p < top; i++, p += 4) { |
| if (p >= bottom && p < top) { |
| unsigned long val; |
| if (__get_user(val, (unsigned long *)p) == 0) |
| sprintf(str + i * 9, " %08lx", val); |
| else |
| sprintf(str + i * 9, " ????????"); |
| } |
| } |
| printk("%s%04lx:%s\n", lvl, first & 0xffff, str); |
| } |
| |
| set_fs(fs); |
| } |
| |
| static void __dump_instr(const char *lvl, struct pt_regs *regs) |
| { |
| unsigned long addr = instruction_pointer(regs); |
| const int thumb = thumb_mode(regs); |
| const int width = thumb ? 4 : 8; |
| char str[sizeof("00000000 ") * 5 + 2 + 1], *p = str; |
| int i; |
| |
| /* |
| * Note that we now dump the code first, just in case the backtrace |
| * kills us. |
| */ |
| |
| for (i = -4; i < 1 + !!thumb; i++) { |
| unsigned int val, bad; |
| |
| if (thumb) |
| bad = get_user(val, &((u16 *)addr)[i]); |
| else |
| bad = get_user(val, &((u32 *)addr)[i]); |
| |
| if (!bad) |
| p += sprintf(p, i == 0 ? "(%0*x) " : "%0*x ", |
| width, val); |
| else { |
| p += sprintf(p, "bad PC value"); |
| break; |
| } |
| } |
| printk("%sCode: %s\n", lvl, str); |
| } |
| |
| static void dump_instr(const char *lvl, struct pt_regs *regs) |
| { |
| mm_segment_t fs; |
| |
| if (!user_mode(regs)) { |
| fs = get_fs(); |
| set_fs(KERNEL_DS); |
| __dump_instr(lvl, regs); |
| set_fs(fs); |
| } else { |
| __dump_instr(lvl, regs); |
| } |
| } |
| |
| #ifdef CONFIG_ARM_UNWIND |
| static inline void dump_backtrace(struct pt_regs *regs, struct task_struct *tsk) |
| { |
| unwind_backtrace(regs, tsk); |
| } |
| #else |
| static void dump_backtrace(struct pt_regs *regs, struct task_struct *tsk) |
| { |
| unsigned int fp, mode; |
| int ok = 1; |
| |
| printk("Backtrace: "); |
| |
| if (!tsk) |
| tsk = current; |
| |
| if (regs) { |
| fp = frame_pointer(regs); |
| mode = processor_mode(regs); |
| } else if (tsk != current) { |
| fp = thread_saved_fp(tsk); |
| mode = 0x10; |
| } else { |
| asm("mov %0, fp" : "=r" (fp) : : "cc"); |
| mode = 0x10; |
| } |
| |
| if (!fp) { |
| pr_cont("no frame pointer"); |
| ok = 0; |
| } else if (verify_stack(fp)) { |
| pr_cont("invalid frame pointer 0x%08x", fp); |
| ok = 0; |
| } else if (fp < (unsigned long)end_of_stack(tsk)) |
| pr_cont("frame pointer underflow"); |
| pr_cont("\n"); |
| |
| if (ok) |
| c_backtrace(fp, mode); |
| } |
| #endif |
| |
| void show_stack(struct task_struct *tsk, unsigned long *sp) |
| { |
| dump_backtrace(NULL, tsk); |
| barrier(); |
| } |
| |
| #ifdef CONFIG_PREEMPT |
| #define S_PREEMPT " PREEMPT" |
| #else |
| #define S_PREEMPT "" |
| #endif |
| #ifdef CONFIG_SMP |
| #define S_SMP " SMP" |
| #else |
| #define S_SMP "" |
| #endif |
| #ifdef CONFIG_THUMB2_KERNEL |
| #define S_ISA " THUMB2" |
| #else |
| #define S_ISA " ARM" |
| #endif |
| |
| static int __die(const char *str, int err, struct pt_regs *regs) |
| { |
| struct task_struct *tsk = current; |
| static int die_counter; |
| int ret; |
| |
| pr_emerg("Internal error: %s: %x [#%d]" S_PREEMPT S_SMP S_ISA "\n", |
| str, err, ++die_counter); |
| |
| /* trap and error numbers are mostly meaningless on ARM */ |
| ret = notify_die(DIE_OOPS, str, regs, err, tsk->thread.trap_no, SIGSEGV); |
| if (ret == NOTIFY_STOP) |
| return 1; |
| |
| print_modules(); |
| __show_regs(regs); |
| pr_emerg("Process %.*s (pid: %d, stack limit = 0x%p)\n", |
| TASK_COMM_LEN, tsk->comm, task_pid_nr(tsk), end_of_stack(tsk)); |
| |
| if (!user_mode(regs) || in_interrupt()) { |
| dump_mem(KERN_EMERG, "Stack: ", regs->ARM_sp, |
| THREAD_SIZE + (unsigned long)task_stack_page(tsk)); |
| dump_backtrace(regs, tsk); |
| dump_instr(KERN_EMERG, regs); |
| } |
| |
| return 0; |
| } |
| |
| static arch_spinlock_t die_lock = __ARCH_SPIN_LOCK_UNLOCKED; |
| static int die_owner = -1; |
| static unsigned int die_nest_count; |
| |
| static unsigned long oops_begin(void) |
| { |
| int cpu; |
| unsigned long flags; |
| |
| oops_enter(); |
| |
| /* racy, but better than risking deadlock. */ |
| raw_local_irq_save(flags); |
| cpu = smp_processor_id(); |
| if (!arch_spin_trylock(&die_lock)) { |
| if (cpu == die_owner) |
| /* nested oops. should stop eventually */; |
| else |
| arch_spin_lock(&die_lock); |
| } |
| die_nest_count++; |
| die_owner = cpu; |
| console_verbose(); |
| bust_spinlocks(1); |
| return flags; |
| } |
| |
| static void oops_end(unsigned long flags, struct pt_regs *regs, int signr) |
| { |
| if (regs && kexec_should_crash(current)) |
| crash_kexec(regs); |
| |
| bust_spinlocks(0); |
| die_owner = -1; |
| add_taint(TAINT_DIE, LOCKDEP_NOW_UNRELIABLE); |
| die_nest_count--; |
| if (!die_nest_count) |
| /* Nest count reaches zero, release the lock. */ |
| arch_spin_unlock(&die_lock); |
| raw_local_irq_restore(flags); |
| oops_exit(); |
| |
| if (in_interrupt()) |
| panic("Fatal exception in interrupt"); |
| if (panic_on_oops) |
| panic("Fatal exception"); |
| if (signr) |
| do_exit(signr); |
| } |
| |
| /* |
| * This function is protected against re-entrancy. |
| */ |
| void die(const char *str, struct pt_regs *regs, int err) |
| { |
| enum bug_trap_type bug_type = BUG_TRAP_TYPE_NONE; |
| unsigned long flags = oops_begin(); |
| int sig = SIGSEGV; |
| |
| if (!user_mode(regs)) |
| bug_type = report_bug(regs->ARM_pc, regs); |
| if (bug_type != BUG_TRAP_TYPE_NONE) |
| str = "Oops - BUG"; |
| |
| if (__die(str, err, regs)) |
| sig = 0; |
| |
| oops_end(flags, regs, sig); |
| } |
| |
| void arm_notify_die(const char *str, struct pt_regs *regs, |
| struct siginfo *info, unsigned long err, unsigned long trap) |
| { |
| if (user_mode(regs)) { |
| current->thread.error_code = err; |
| current->thread.trap_no = trap; |
| |
| force_sig_info(info->si_signo, info, current); |
| } else { |
| die(str, regs, err); |
| } |
| } |
| |
| #ifdef CONFIG_GENERIC_BUG |
| |
| int is_valid_bugaddr(unsigned long pc) |
| { |
| #ifdef CONFIG_THUMB2_KERNEL |
| u16 bkpt; |
| u16 insn = __opcode_to_mem_thumb16(BUG_INSTR_VALUE); |
| #else |
| u32 bkpt; |
| u32 insn = __opcode_to_mem_arm(BUG_INSTR_VALUE); |
| #endif |
| |
| if (probe_kernel_address((unsigned *)pc, bkpt)) |
| return 0; |
| |
| return bkpt == insn; |
| } |
| |
| #endif |
| |
| static LIST_HEAD(undef_hook); |
| static DEFINE_RAW_SPINLOCK(undef_lock); |
| |
| void register_undef_hook(struct undef_hook *hook) |
| { |
| unsigned long flags; |
| |
| raw_spin_lock_irqsave(&undef_lock, flags); |
| list_add(&hook->node, &undef_hook); |
| raw_spin_unlock_irqrestore(&undef_lock, flags); |
| } |
| |
| void unregister_undef_hook(struct undef_hook *hook) |
| { |
| unsigned long flags; |
| |
| raw_spin_lock_irqsave(&undef_lock, flags); |
| list_del(&hook->node); |
| raw_spin_unlock_irqrestore(&undef_lock, flags); |
| } |
| |
| static nokprobe_inline |
| int call_undef_hook(struct pt_regs *regs, unsigned int instr) |
| { |
| struct undef_hook *hook; |
| unsigned long flags; |
| int (*fn)(struct pt_regs *regs, unsigned int instr) = NULL; |
| |
| raw_spin_lock_irqsave(&undef_lock, flags); |
| list_for_each_entry(hook, &undef_hook, node) |
| if ((instr & hook->instr_mask) == hook->instr_val && |
| (regs->ARM_cpsr & hook->cpsr_mask) == hook->cpsr_val) |
| fn = hook->fn; |
| raw_spin_unlock_irqrestore(&undef_lock, flags); |
| |
| return fn ? fn(regs, instr) : 1; |
| } |
| |
| asmlinkage void __exception do_undefinstr(struct pt_regs *regs) |
| { |
| unsigned int instr; |
| siginfo_t info; |
| void __user *pc; |
| |
| pc = (void __user *)instruction_pointer(regs); |
| |
| if (processor_mode(regs) == SVC_MODE) { |
| #ifdef CONFIG_THUMB2_KERNEL |
| if (thumb_mode(regs)) { |
| instr = __mem_to_opcode_thumb16(((u16 *)pc)[0]); |
| if (is_wide_instruction(instr)) { |
| u16 inst2; |
| inst2 = __mem_to_opcode_thumb16(((u16 *)pc)[1]); |
| instr = __opcode_thumb32_compose(instr, inst2); |
| } |
| } else |
| #endif |
| instr = __mem_to_opcode_arm(*(u32 *) pc); |
| } else if (thumb_mode(regs)) { |
| if (get_user(instr, (u16 __user *)pc)) |
| goto die_sig; |
| instr = __mem_to_opcode_thumb16(instr); |
| if (is_wide_instruction(instr)) { |
| unsigned int instr2; |
| if (get_user(instr2, (u16 __user *)pc+1)) |
| goto die_sig; |
| instr2 = __mem_to_opcode_thumb16(instr2); |
| instr = __opcode_thumb32_compose(instr, instr2); |
| } |
| } else { |
| if (get_user(instr, (u32 __user *)pc)) |
| goto die_sig; |
| instr = __mem_to_opcode_arm(instr); |
| } |
| |
| if (call_undef_hook(regs, instr) == 0) |
| return; |
| |
| die_sig: |
| #ifdef CONFIG_DEBUG_USER |
| if (user_debug & UDBG_UNDEFINED) { |
| pr_info("%s (%d): undefined instruction: pc=%p\n", |
| current->comm, task_pid_nr(current), pc); |
| __show_regs(regs); |
| dump_instr(KERN_INFO, regs); |
| } |
| #endif |
| |
| info.si_signo = SIGILL; |
| info.si_errno = 0; |
| info.si_code = ILL_ILLOPC; |
| info.si_addr = pc; |
| |
| arm_notify_die("Oops - undefined instruction", regs, &info, 0, 6); |
| } |
| NOKPROBE_SYMBOL(do_undefinstr) |
| |
| /* |
| * Handle FIQ similarly to NMI on x86 systems. |
| * |
| * The runtime environment for NMIs is extremely restrictive |
| * (NMIs can pre-empt critical sections meaning almost all locking is |
| * forbidden) meaning this default FIQ handling must only be used in |
| * circumstances where non-maskability improves robustness, such as |
| * watchdog or debug logic. |
| * |
| * This handler is not appropriate for general purpose use in drivers |
| * platform code and can be overrideen using set_fiq_handler. |
| */ |
| asmlinkage void __exception_irq_entry handle_fiq_as_nmi(struct pt_regs *regs) |
| { |
| struct pt_regs *old_regs = set_irq_regs(regs); |
| |
| nmi_enter(); |
| |
| /* nop. FIQ handlers for special arch/arm features can be added here. */ |
| |
| nmi_exit(); |
| |
| set_irq_regs(old_regs); |
| } |
| |
| /* |
| * bad_mode handles the impossible case in the vectors. If you see one of |
| * these, then it's extremely serious, and could mean you have buggy hardware. |
| * It never returns, and never tries to sync. We hope that we can at least |
| * dump out some state information... |
| */ |
| asmlinkage void bad_mode(struct pt_regs *regs, int reason) |
| { |
| console_verbose(); |
| |
| pr_crit("Bad mode in %s handler detected\n", handler[reason]); |
| |
| die("Oops - bad mode", regs, 0); |
| local_irq_disable(); |
| panic("bad mode"); |
| } |
| |
| static int bad_syscall(int n, struct pt_regs *regs) |
| { |
| siginfo_t info; |
| |
| if ((current->personality & PER_MASK) != PER_LINUX) { |
| send_sig(SIGSEGV, current, 1); |
| return regs->ARM_r0; |
| } |
| |
| #ifdef CONFIG_DEBUG_USER |
| if (user_debug & UDBG_SYSCALL) { |
| pr_err("[%d] %s: obsolete system call %08x.\n", |
| task_pid_nr(current), current->comm, n); |
| dump_instr(KERN_ERR, regs); |
| } |
| #endif |
| |
| info.si_signo = SIGILL; |
| info.si_errno = 0; |
| info.si_code = ILL_ILLTRP; |
| info.si_addr = (void __user *)instruction_pointer(regs) - |
| (thumb_mode(regs) ? 2 : 4); |
| |
| arm_notify_die("Oops - bad syscall", regs, &info, n, 0); |
| |
| return regs->ARM_r0; |
| } |
| |
| static inline int |
| __do_cache_op(unsigned long start, unsigned long end) |
| { |
| int ret; |
| |
| do { |
| unsigned long chunk = min(PAGE_SIZE, end - start); |
| |
| if (fatal_signal_pending(current)) |
| return 0; |
| |
| ret = flush_cache_user_range(start, start + chunk); |
| if (ret) |
| return ret; |
| |
| cond_resched(); |
| start += chunk; |
| } while (start < end); |
| |
| return 0; |
| } |
| |
| static inline int |
| do_cache_op(unsigned long start, unsigned long end, int flags) |
| { |
| if (end < start || flags) |
| return -EINVAL; |
| |
| if (!access_ok(VERIFY_READ, start, end - start)) |
| return -EFAULT; |
| |
| return __do_cache_op(start, end); |
| } |
| |
| /* |
| * Handle all unrecognised system calls. |
| * 0x9f0000 - 0x9fffff are some more esoteric system calls |
| */ |
| #define NR(x) ((__ARM_NR_##x) - __ARM_NR_BASE) |
| asmlinkage int arm_syscall(int no, struct pt_regs *regs) |
| { |
| siginfo_t info; |
| |
| if ((no >> 16) != (__ARM_NR_BASE>> 16)) |
| return bad_syscall(no, regs); |
| |
| switch (no & 0xffff) { |
| case 0: /* branch through 0 */ |
| info.si_signo = SIGSEGV; |
| info.si_errno = 0; |
| info.si_code = SEGV_MAPERR; |
| info.si_addr = NULL; |
| |
| arm_notify_die("branch through zero", regs, &info, 0, 0); |
| return 0; |
| |
| case NR(breakpoint): /* SWI BREAK_POINT */ |
| regs->ARM_pc -= thumb_mode(regs) ? 2 : 4; |
| ptrace_break(current, regs); |
| return regs->ARM_r0; |
| |
| /* |
| * Flush a region from virtual address 'r0' to virtual address 'r1' |
| * _exclusive_. There is no alignment requirement on either address; |
| * user space does not need to know the hardware cache layout. |
| * |
| * r2 contains flags. It should ALWAYS be passed as ZERO until it |
| * is defined to be something else. For now we ignore it, but may |
| * the fires of hell burn in your belly if you break this rule. ;) |
| * |
| * (at a later date, we may want to allow this call to not flush |
| * various aspects of the cache. Passing '0' will guarantee that |
| * everything necessary gets flushed to maintain consistency in |
| * the specified region). |
| */ |
| case NR(cacheflush): |
| return do_cache_op(regs->ARM_r0, regs->ARM_r1, regs->ARM_r2); |
| |
| case NR(usr26): |
| if (!(elf_hwcap & HWCAP_26BIT)) |
| break; |
| regs->ARM_cpsr &= ~MODE32_BIT; |
| return regs->ARM_r0; |
| |
| case NR(usr32): |
| if (!(elf_hwcap & HWCAP_26BIT)) |
| break; |
| regs->ARM_cpsr |= MODE32_BIT; |
| return regs->ARM_r0; |
| |
| case NR(set_tls): |
| set_tls(regs->ARM_r0); |
| return 0; |
| |
| default: |
| /* Calls 9f00xx..9f07ff are defined to return -ENOSYS |
| if not implemented, rather than raising SIGILL. This |
| way the calling program can gracefully determine whether |
| a feature is supported. */ |
| if ((no & 0xffff) <= 0x7ff) |
| return -ENOSYS; |
| break; |
| } |
| #ifdef CONFIG_DEBUG_USER |
| /* |
| * experience shows that these seem to indicate that |
| * something catastrophic has happened |
| */ |
| if (user_debug & UDBG_SYSCALL) { |
| pr_err("[%d] %s: arm syscall %d\n", |
| task_pid_nr(current), current->comm, no); |
| dump_instr("", regs); |
| if (user_mode(regs)) { |
| __show_regs(regs); |
| c_backtrace(frame_pointer(regs), processor_mode(regs)); |
| } |
| } |
| #endif |
| info.si_signo = SIGILL; |
| info.si_errno = 0; |
| info.si_code = ILL_ILLTRP; |
| info.si_addr = (void __user *)instruction_pointer(regs) - |
| (thumb_mode(regs) ? 2 : 4); |
| |
| arm_notify_die("Oops - bad syscall(2)", regs, &info, no, 0); |
| return 0; |
| } |
| |
| #ifdef CONFIG_TLS_REG_EMUL |
| |
| /* |
| * We might be running on an ARMv6+ processor which should have the TLS |
| * register but for some reason we can't use it, or maybe an SMP system |
| * using a pre-ARMv6 processor (there are apparently a few prototypes like |
| * that in existence) and therefore access to that register must be |
| * emulated. |
| */ |
| |
| static int get_tp_trap(struct pt_regs *regs, unsigned int instr) |
| { |
| int reg = (instr >> 12) & 15; |
| if (reg == 15) |
| return 1; |
| regs->uregs[reg] = current_thread_info()->tp_value[0]; |
| regs->ARM_pc += 4; |
| return 0; |
| } |
| |
| static struct undef_hook arm_mrc_hook = { |
| .instr_mask = 0x0fff0fff, |
| .instr_val = 0x0e1d0f70, |
| .cpsr_mask = PSR_T_BIT, |
| .cpsr_val = 0, |
| .fn = get_tp_trap, |
| }; |
| |
| static int __init arm_mrc_hook_init(void) |
| { |
| register_undef_hook(&arm_mrc_hook); |
| return 0; |
| } |
| |
| late_initcall(arm_mrc_hook_init); |
| |
| #endif |
| |
| /* |
| * A data abort trap was taken, but we did not handle the instruction. |
| * Try to abort the user program, or panic if it was the kernel. |
| */ |
| asmlinkage void |
| baddataabort(int code, unsigned long instr, struct pt_regs *regs) |
| { |
| unsigned long addr = instruction_pointer(regs); |
| siginfo_t info; |
| |
| #ifdef CONFIG_DEBUG_USER |
| if (user_debug & UDBG_BADABORT) { |
| pr_err("[%d] %s: bad data abort: code %d instr 0x%08lx\n", |
| task_pid_nr(current), current->comm, code, instr); |
| dump_instr(KERN_ERR, regs); |
| show_pte(current->mm, addr); |
| } |
| #endif |
| |
| info.si_signo = SIGILL; |
| info.si_errno = 0; |
| info.si_code = ILL_ILLOPC; |
| info.si_addr = (void __user *)addr; |
| |
| arm_notify_die("unknown data abort code", regs, &info, instr, 0); |
| } |
| |
| void __readwrite_bug(const char *fn) |
| { |
| pr_err("%s called, but not implemented\n", fn); |
| BUG(); |
| } |
| EXPORT_SYMBOL(__readwrite_bug); |
| |
| void __pte_error(const char *file, int line, pte_t pte) |
| { |
| pr_err("%s:%d: bad pte %08llx.\n", file, line, (long long)pte_val(pte)); |
| } |
| |
| void __pmd_error(const char *file, int line, pmd_t pmd) |
| { |
| pr_err("%s:%d: bad pmd %08llx.\n", file, line, (long long)pmd_val(pmd)); |
| } |
| |
| void __pgd_error(const char *file, int line, pgd_t pgd) |
| { |
| pr_err("%s:%d: bad pgd %08llx.\n", file, line, (long long)pgd_val(pgd)); |
| } |
| |
| asmlinkage void __div0(void) |
| { |
| pr_err("Division by zero in kernel.\n"); |
| dump_stack(); |
| } |
| EXPORT_SYMBOL(__div0); |
| |
| void abort(void) |
| { |
| BUG(); |
| |
| /* if that doesn't kill us, halt */ |
| panic("Oops failed to kill thread"); |
| } |
| EXPORT_SYMBOL(abort); |
| |
| void __init trap_init(void) |
| { |
| return; |
| } |
| |
| #ifdef CONFIG_KUSER_HELPERS |
| static void __init kuser_init(void *vectors) |
| { |
| extern char __kuser_helper_start[], __kuser_helper_end[]; |
| int kuser_sz = __kuser_helper_end - __kuser_helper_start; |
| |
| memcpy(vectors + 0x1000 - kuser_sz, __kuser_helper_start, kuser_sz); |
| |
| /* |
| * vectors + 0xfe0 = __kuser_get_tls |
| * vectors + 0xfe8 = hardware TLS instruction at 0xffff0fe8 |
| */ |
| if (tls_emu || has_tls_reg) |
| memcpy(vectors + 0xfe0, vectors + 0xfe8, 4); |
| } |
| #else |
| static inline void __init kuser_init(void *vectors) |
| { |
| } |
| #endif |
| |
| void __init early_trap_init(void *vectors_base) |
| { |
| #ifndef CONFIG_CPU_V7M |
| unsigned long vectors = (unsigned long)vectors_base; |
| extern char __stubs_start[], __stubs_end[]; |
| extern char __vectors_start[], __vectors_end[]; |
| unsigned i; |
| |
| vectors_page = vectors_base; |
| |
| /* |
| * Poison the vectors page with an undefined instruction. This |
| * instruction is chosen to be undefined for both ARM and Thumb |
| * ISAs. The Thumb version is an undefined instruction with a |
| * branch back to the undefined instruction. |
| */ |
| for (i = 0; i < PAGE_SIZE / sizeof(u32); i++) |
| ((u32 *)vectors_base)[i] = 0xe7fddef1; |
| |
| /* |
| * Copy the vectors, stubs and kuser helpers (in entry-armv.S) |
| * into the vector page, mapped at 0xffff0000, and ensure these |
| * are visible to the instruction stream. |
| */ |
| memcpy((void *)vectors, __vectors_start, __vectors_end - __vectors_start); |
| memcpy((void *)vectors + 0x1000, __stubs_start, __stubs_end - __stubs_start); |
| |
| kuser_init(vectors_base); |
| |
| flush_icache_range(vectors, vectors + PAGE_SIZE * 2); |
| #else /* ifndef CONFIG_CPU_V7M */ |
| /* |
| * on V7-M there is no need to copy the vector table to a dedicated |
| * memory area. The address is configurable and so a table in the kernel |
| * image can be used. |
| */ |
| #endif |
| } |