3 #include <linux/types.h>
4 #include <linux/kdebug.h>
5 #include <linux/signal.h>
6 #include <linux/sched.h>
7 #include <linux/sched/debug.h>
8 #include <linux/sched/task_stack.h>
9 #include <linux/uaccess.h>
10 #include <linux/hardirq.h>
11 #include <linux/kernel.h>
12 #include <linux/kexec.h>
13 #include <linux/sched/signal.h>
15 #include <linux/extable.h>
16 #include <linux/module.h> /* print_modules */
17 #include <asm/unwinder.h>
18 #include <asm/traps.h>
20 static DEFINE_SPINLOCK(die_lock);
22 void die(const char *str, struct pt_regs *regs, long err)
24 static int die_counter;
28 spin_lock_irq(&die_lock);
32 printk("%s: %04lx [#%d]\n", str, err & 0xffff, ++die_counter);
36 printk("Process: %s (pid: %d, stack limit = %p)\n", current->comm,
37 task_pid_nr(current), task_stack_page(current) + 1);
39 if (!user_mode(regs) || in_interrupt())
40 dump_mem("Stack: ", regs->regs[15], THREAD_SIZE +
41 (unsigned long)task_stack_page(current));
43 notify_die(DIE_OOPS, str, regs, err, 255, SIGSEGV);
46 add_taint(TAINT_DIE, LOCKDEP_NOW_UNRELIABLE);
47 spin_unlock_irq(&die_lock);
50 if (kexec_should_crash(current))
54 panic("Fatal exception in interrupt");
57 panic("Fatal exception");
62 void die_if_kernel(const char *str, struct pt_regs *regs, long err)
69 * try and fix up kernelspace address errors
70 * - userspace errors just cause EFAULT to be returned, resulting in SEGV
71 * - kernel/userspace interfaces cause a jump to an appropriate handler
72 * - other kernel errors are bad
74 void die_if_no_fixup(const char *str, struct pt_regs *regs, long err)
76 if (!user_mode(regs)) {
77 const struct exception_table_entry *fixup;
78 fixup = search_exception_tables(regs->pc);
80 regs->pc = fixup->fixup;
88 #ifdef CONFIG_GENERIC_BUG
89 static void handle_BUG(struct pt_regs *regs)
91 const struct bug_entry *bug;
92 unsigned long bugaddr = regs->pc;
93 enum bug_trap_type tt;
95 if (!is_valid_bugaddr(bugaddr))
98 bug = find_bug(bugaddr);
100 /* Switch unwinders when unwind_stack() is called */
101 if (bug->flags & BUGFLAG_UNWINDER)
102 unwinder_faulted = 1;
104 tt = report_bug(bugaddr, regs);
105 if (tt == BUG_TRAP_TYPE_WARN) {
106 regs->pc += instruction_size(bugaddr);
111 die("Kernel BUG", regs, TRAPA_BUG_OPCODE & 0xff);
114 int is_valid_bugaddr(unsigned long addr)
118 if (addr < PAGE_OFFSET)
120 if (probe_kernel_address((insn_size_t *)addr, opcode))
122 if (opcode == TRAPA_BUG_OPCODE)
130 * Generic trap handler.
132 BUILD_TRAP_HANDLER(debug)
137 regs->pc -= instruction_size(__raw_readw(regs->pc - 4));
139 if (notify_die(DIE_TRAP, "debug trap", regs, 0, vec & 0xff,
140 SIGTRAP) == NOTIFY_STOP)
143 force_sig(SIGTRAP, current);
147 * Special handler for BUG() traps.
149 BUILD_TRAP_HANDLER(bug)
154 regs->pc -= instruction_size(__raw_readw(regs->pc - 4));
156 if (notify_die(DIE_TRAP, "bug trap", regs, 0, TRAPA_BUG_OPCODE & 0xff,
157 SIGTRAP) == NOTIFY_STOP)
160 #ifdef CONFIG_GENERIC_BUG
161 if (__kernel_text_address(instruction_pointer(regs))) {
162 insn_size_t insn = *(insn_size_t *)instruction_pointer(regs);
163 if (insn == TRAPA_BUG_OPCODE)
169 force_sig(SIGTRAP, current);
172 BUILD_TRAP_HANDLER(nmi)
174 unsigned int cpu = smp_processor_id();
180 switch (notify_die(DIE_NMI, "NMI", regs, 0, vec & 0xff, SIGINT)) {
185 die("Fatal Non-Maskable Interrupt", regs, SIGINT);
187 printk(KERN_ALERT "Got NMI, but nobody cared. Ignoring...\n");