Commit | Line | Data |
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5a4f7c66 PM |
1 | #include <linux/bug.h> |
2 | #include <linux/io.h> | |
3 | #include <linux/types.h> | |
4 | #include <linux/kdebug.h> | |
47a3eb95 PM |
5 | #include <linux/signal.h> |
6 | #include <linux/sched.h> | |
9a33fc21 | 7 | #include <linux/uaccess.h> |
1e1030dc | 8 | #include <linux/hardirq.h> |
e115f2c1 | 9 | #include <asm/unwinder.h> |
5a4f7c66 PM |
10 | #include <asm/system.h> |
11 | ||
12 | #ifdef CONFIG_BUG | |
b344e24a | 13 | void handle_BUG(struct pt_regs *regs) |
5a4f7c66 | 14 | { |
e115f2c1 PM |
15 | const struct bug_entry *bug; |
16 | unsigned long bugaddr = regs->pc; | |
5a4f7c66 | 17 | enum bug_trap_type tt; |
e115f2c1 PM |
18 | |
19 | if (!is_valid_bugaddr(bugaddr)) | |
20 | goto invalid; | |
21 | ||
22 | bug = find_bug(bugaddr); | |
23 | ||
24 | /* Switch unwinders when unwind_stack() is called */ | |
25 | if (bug->flags & BUGFLAG_UNWINDER) | |
26 | unwinder_faulted = 1; | |
27 | ||
28 | tt = report_bug(bugaddr, regs); | |
5a4f7c66 | 29 | if (tt == BUG_TRAP_TYPE_WARN) { |
e115f2c1 | 30 | regs->pc += instruction_size(bugaddr); |
5a4f7c66 PM |
31 | return; |
32 | } | |
33 | ||
e115f2c1 | 34 | invalid: |
5a4f7c66 PM |
35 | die("Kernel BUG", regs, TRAPA_BUG_OPCODE & 0xff); |
36 | } | |
37 | ||
38 | int is_valid_bugaddr(unsigned long addr) | |
39 | { | |
2bcfffa4 | 40 | insn_size_t opcode; |
9a33fc21 PM |
41 | |
42 | if (addr < PAGE_OFFSET) | |
43 | return 0; | |
2bcfffa4 | 44 | if (probe_kernel_address((insn_size_t *)addr, opcode)) |
9a33fc21 | 45 | return 0; |
e115f2c1 | 46 | if (opcode == TRAPA_BUG_OPCODE) |
b344e24a MF |
47 | return 1; |
48 | ||
49 | return 0; | |
5a4f7c66 PM |
50 | } |
51 | #endif | |
52 | ||
53 | /* | |
54 | * Generic trap handler. | |
55 | */ | |
56 | BUILD_TRAP_HANDLER(debug) | |
57 | { | |
58 | TRAP_HANDLER_DECL; | |
59 | ||
60 | /* Rewind */ | |
61 | regs->pc -= instruction_size(ctrl_inw(regs->pc - 4)); | |
62 | ||
63 | if (notify_die(DIE_TRAP, "debug trap", regs, 0, vec & 0xff, | |
64 | SIGTRAP) == NOTIFY_STOP) | |
65 | return; | |
66 | ||
67 | force_sig(SIGTRAP, current); | |
68 | } | |
69 | ||
70 | /* | |
71 | * Special handler for BUG() traps. | |
72 | */ | |
73 | BUILD_TRAP_HANDLER(bug) | |
74 | { | |
75 | TRAP_HANDLER_DECL; | |
76 | ||
77 | /* Rewind */ | |
78 | regs->pc -= instruction_size(ctrl_inw(regs->pc - 4)); | |
79 | ||
80 | if (notify_die(DIE_TRAP, "bug trap", regs, 0, TRAPA_BUG_OPCODE & 0xff, | |
81 | SIGTRAP) == NOTIFY_STOP) | |
82 | return; | |
83 | ||
84 | #ifdef CONFIG_BUG | |
85 | if (__kernel_text_address(instruction_pointer(regs))) { | |
2bcfffa4 | 86 | insn_size_t insn = *(insn_size_t *)instruction_pointer(regs); |
5a4f7c66 PM |
87 | if (insn == TRAPA_BUG_OPCODE) |
88 | handle_BUG(regs); | |
0ec39885 | 89 | return; |
5a4f7c66 PM |
90 | } |
91 | #endif | |
92 | ||
93 | force_sig(SIGTRAP, current); | |
94 | } | |
1e1030dc PM |
95 | |
96 | BUILD_TRAP_HANDLER(nmi) | |
97 | { | |
98 | TRAP_HANDLER_DECL; | |
99 | ||
100 | nmi_enter(); | |
101 | ||
102 | switch (notify_die(DIE_NMI, "NMI", regs, 0, vec & 0xff, SIGINT)) { | |
103 | case NOTIFY_OK: | |
104 | case NOTIFY_STOP: | |
105 | break; | |
106 | case NOTIFY_BAD: | |
107 | die("Fatal Non-Maskable Interrupt", regs, SIGINT); | |
108 | default: | |
109 | printk(KERN_ALERT "Got NMI, but nobody cared. Ignoring...\n"); | |
110 | break; | |
111 | } | |
112 | ||
113 | nmi_exit(); | |
114 | } |