| /* |
| * Based on arch/arm/kernel/traps.c |
| * |
| * Copyright (C) 1995-2009 Russell King |
| * Copyright (C) 2012 ARM Ltd. |
| * |
| * 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. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with this program. If not, see <http://www.gnu.org/licenses/>. |
| */ |
| |
| #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/module.h> |
| #include <linux/kexec.h> |
| #include <linux/delay.h> |
| #include <linux/init.h> |
| #include <linux/sched.h> |
| #include <linux/syscalls.h> |
| |
| #include <asm/atomic.h> |
| #include <asm/debug-monitors.h> |
| #include <asm/traps.h> |
| #include <asm/stacktrace.h> |
| #include <asm/exception.h> |
| #include <asm/system_misc.h> |
| |
| static const char *handler[]= { |
| "Synchronous Abort", |
| "IRQ", |
| "FIQ", |
| "Error" |
| }; |
| |
| int show_unhandled_signals = 1; |
| |
| /* |
| * 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%016lx to 0x%016lx)\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 int val; |
| if (__get_user(val, (unsigned int *)p) == 0) |
| sprintf(str + i * 9, " %08x", val); |
| else |
| sprintf(str + i * 9, " ????????"); |
| } |
| } |
| printk("%s%04lx:%s\n", lvl, first & 0xffff, str); |
| } |
| |
| set_fs(fs); |
| } |
| |
| static void dump_backtrace_entry(unsigned long where, unsigned long stack) |
| { |
| print_ip_sym(where); |
| if (in_exception_text(where)) |
| dump_mem("", "Exception stack", stack, |
| stack + sizeof(struct pt_regs)); |
| } |
| |
| static void dump_instr(const char *lvl, struct pt_regs *regs) |
| { |
| unsigned long addr = instruction_pointer(regs); |
| mm_segment_t fs; |
| char str[sizeof("00000000 ") * 5 + 2 + 1], *p = str; |
| 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); |
| |
| for (i = -4; i < 1; i++) { |
| unsigned int val, bad; |
| |
| bad = __get_user(val, &((u32 *)addr)[i]); |
| |
| if (!bad) |
| p += sprintf(p, i == 0 ? "(%08x) " : "%08x ", val); |
| else { |
| p += sprintf(p, "bad PC value"); |
| break; |
| } |
| } |
| printk("%sCode: %s\n", lvl, str); |
| |
| set_fs(fs); |
| } |
| |
| static void dump_backtrace(struct pt_regs *regs, struct task_struct *tsk) |
| { |
| struct stackframe frame; |
| |
| pr_debug("%s(regs = %p tsk = %p)\n", __func__, regs, tsk); |
| |
| if (!tsk) |
| tsk = current; |
| |
| if (regs) { |
| frame.fp = regs->regs[29]; |
| frame.sp = regs->sp; |
| frame.pc = regs->pc; |
| } else if (tsk == current) { |
| frame.fp = (unsigned long)__builtin_frame_address(0); |
| frame.sp = current_stack_pointer; |
| frame.pc = (unsigned long)dump_backtrace; |
| } else { |
| /* |
| * task blocked in __switch_to |
| */ |
| frame.fp = thread_saved_fp(tsk); |
| frame.sp = thread_saved_sp(tsk); |
| frame.pc = thread_saved_pc(tsk); |
| } |
| |
| pr_emerg("Call trace:\n"); |
| while (1) { |
| unsigned long where = frame.pc; |
| int ret; |
| |
| ret = unwind_frame(&frame); |
| if (ret < 0) |
| break; |
| dump_backtrace_entry(where, frame.sp); |
| } |
| } |
| |
| 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 |
| |
| static int __die(const char *str, int err, struct thread_info *thread, |
| struct pt_regs *regs) |
| { |
| struct task_struct *tsk = thread->task; |
| static int die_counter; |
| int ret; |
| |
| pr_emerg("Internal error: %s: %x [#%d]" S_PREEMPT S_SMP "\n", |
| str, err, ++die_counter); |
| |
| /* trap and error numbers are mostly meaningless on ARM */ |
| ret = notify_die(DIE_OOPS, str, regs, err, 0, SIGSEGV); |
| if (ret == NOTIFY_STOP) |
| return ret; |
| |
| 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), thread + 1); |
| |
| if (!user_mode(regs) || in_interrupt()) { |
| dump_mem(KERN_EMERG, "Stack: ", regs->sp, |
| THREAD_SIZE + (unsigned long)task_stack_page(tsk)); |
| dump_backtrace(regs, tsk); |
| dump_instr(KERN_EMERG, regs); |
| } |
| |
| return ret; |
| } |
| |
| static DEFINE_RAW_SPINLOCK(die_lock); |
| |
| /* |
| * This function is protected against re-entrancy. |
| */ |
| void die(const char *str, struct pt_regs *regs, int err) |
| { |
| struct thread_info *thread = current_thread_info(); |
| int ret; |
| |
| oops_enter(); |
| |
| raw_spin_lock_irq(&die_lock); |
| console_verbose(); |
| bust_spinlocks(1); |
| ret = __die(str, err, thread, regs); |
| |
| if (regs && kexec_should_crash(thread->task)) |
| crash_kexec(regs); |
| |
| bust_spinlocks(0); |
| add_taint(TAINT_DIE, LOCKDEP_NOW_UNRELIABLE); |
| raw_spin_unlock_irq(&die_lock); |
| oops_exit(); |
| |
| if (in_interrupt()) |
| panic("Fatal exception in interrupt"); |
| if (panic_on_oops) |
| panic("Fatal exception"); |
| if (ret != NOTIFY_STOP) |
| do_exit(SIGSEGV); |
| } |
| |
| void arm64_notify_die(const char *str, struct pt_regs *regs, |
| struct siginfo *info, int err) |
| { |
| if (user_mode(regs)) { |
| current->thread.fault_address = 0; |
| current->thread.fault_code = err; |
| force_sig_info(info->si_signo, info, current); |
| } else { |
| die(str, regs, err); |
| } |
| } |
| |
| 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 int call_undef_hook(struct pt_regs *regs) |
| { |
| struct undef_hook *hook; |
| unsigned long flags; |
| u32 instr; |
| int (*fn)(struct pt_regs *regs, u32 instr) = NULL; |
| void __user *pc = (void __user *)instruction_pointer(regs); |
| |
| if (!user_mode(regs)) |
| return 1; |
| |
| if (compat_thumb_mode(regs)) { |
| /* 16-bit Thumb instruction */ |
| if (get_user(instr, (u16 __user *)pc)) |
| goto exit; |
| instr = le16_to_cpu(instr); |
| if (aarch32_insn_is_wide(instr)) { |
| u32 instr2; |
| |
| if (get_user(instr2, (u16 __user *)(pc + 2))) |
| goto exit; |
| instr2 = le16_to_cpu(instr2); |
| instr = (instr << 16) | instr2; |
| } |
| } else { |
| /* 32-bit ARM instruction */ |
| if (get_user(instr, (u32 __user *)pc)) |
| goto exit; |
| instr = le32_to_cpu(instr); |
| } |
| |
| raw_spin_lock_irqsave(&undef_lock, flags); |
| list_for_each_entry(hook, &undef_hook, node) |
| if ((instr & hook->instr_mask) == hook->instr_val && |
| (regs->pstate & hook->pstate_mask) == hook->pstate_val) |
| fn = hook->fn; |
| |
| raw_spin_unlock_irqrestore(&undef_lock, flags); |
| exit: |
| return fn ? fn(regs, instr) : 1; |
| } |
| |
| asmlinkage void __exception do_undefinstr(struct pt_regs *regs) |
| { |
| siginfo_t info; |
| void __user *pc = (void __user *)instruction_pointer(regs); |
| |
| /* check for AArch32 breakpoint instructions */ |
| if (!aarch32_break_handler(regs)) |
| return; |
| |
| if (call_undef_hook(regs) == 0) |
| return; |
| |
| if (show_unhandled_signals && unhandled_signal(current, SIGILL) && |
| printk_ratelimit()) { |
| pr_info("%s[%d]: undefined instruction: pc=%p\n", |
| current->comm, task_pid_nr(current), pc); |
| dump_instr(KERN_INFO, regs); |
| } |
| |
| info.si_signo = SIGILL; |
| info.si_errno = 0; |
| info.si_code = ILL_ILLOPC; |
| info.si_addr = pc; |
| |
| arm64_notify_die("Oops - undefined instruction", regs, &info, 0); |
| } |
| |
| long compat_arm_syscall(struct pt_regs *regs); |
| |
| asmlinkage long do_ni_syscall(struct pt_regs *regs) |
| { |
| #ifdef CONFIG_COMPAT |
| long ret; |
| if (is_compat_task()) { |
| ret = compat_arm_syscall(regs); |
| if (ret != -ENOSYS) |
| return ret; |
| } |
| #endif |
| |
| if (show_unhandled_signals && printk_ratelimit()) { |
| pr_info("%s[%d]: syscall %d\n", current->comm, |
| task_pid_nr(current), (int)regs->syscallno); |
| dump_instr("", regs); |
| if (user_mode(regs)) |
| __show_regs(regs); |
| } |
| |
| return sys_ni_syscall(); |
| } |
| |
| /* |
| * bad_mode handles the impossible case in the exception vector. |
| */ |
| asmlinkage void bad_mode(struct pt_regs *regs, int reason, unsigned int esr) |
| { |
| siginfo_t info; |
| void __user *pc = (void __user *)instruction_pointer(regs); |
| console_verbose(); |
| |
| pr_crit("Bad mode in %s handler detected, code 0x%08x\n", |
| handler[reason], esr); |
| __show_regs(regs); |
| |
| info.si_signo = SIGILL; |
| info.si_errno = 0; |
| info.si_code = ILL_ILLOPC; |
| info.si_addr = pc; |
| |
| arm64_notify_die("Oops - bad mode", regs, &info, 0); |
| } |
| |
| void __pte_error(const char *file, int line, unsigned long val) |
| { |
| pr_crit("%s:%d: bad pte %016lx.\n", file, line, val); |
| } |
| |
| void __pmd_error(const char *file, int line, unsigned long val) |
| { |
| pr_crit("%s:%d: bad pmd %016lx.\n", file, line, val); |
| } |
| |
| void __pud_error(const char *file, int line, unsigned long val) |
| { |
| pr_crit("%s:%d: bad pud %016lx.\n", file, line, val); |
| } |
| |
| void __pgd_error(const char *file, int line, unsigned long val) |
| { |
| pr_crit("%s:%d: bad pgd %016lx.\n", file, line, val); |
| } |
| |
| void __init trap_init(void) |
| { |
| return; |
| } |