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1#include <linux/bug.h>
2#include <linux/io.h>
3#include <linux/types.h>
4#include <linux/kdebug.h>
5#include <linux/signal.h>
6#include <linux/sched.h>
7#include <linux/uaccess.h>
8#include <linux/hardirq.h>
9#include <asm/unwinder.h>
10#include <asm/traps.h>
11
12#ifdef CONFIG_GENERIC_BUG
13static void handle_BUG(struct pt_regs *regs)
14{
15 const struct bug_entry *bug;
16 unsigned long bugaddr = regs->pc;
17 enum bug_trap_type tt;
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);
29 if (tt == BUG_TRAP_TYPE_WARN) {
30 regs->pc += instruction_size(bugaddr);
31 return;
32 }
33
34invalid:
35 die("Kernel BUG", regs, TRAPA_BUG_OPCODE & 0xff);
36}
37
38int is_valid_bugaddr(unsigned long addr)
39{
40 insn_size_t opcode;
41
42 if (addr < PAGE_OFFSET)
43 return 0;
44 if (probe_kernel_address((insn_size_t *)addr, opcode))
45 return 0;
46 if (opcode == TRAPA_BUG_OPCODE)
47 return 1;
48
49 return 0;
50}
51#endif
52
53/*
54 * Generic trap handler.
55 */
56BUILD_TRAP_HANDLER(debug)
57{
58 TRAP_HANDLER_DECL;
59
60 /* Rewind */
61 regs->pc -= instruction_size(__raw_readw(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 */
73BUILD_TRAP_HANDLER(bug)
74{
75 TRAP_HANDLER_DECL;
76
77 /* Rewind */
78 regs->pc -= instruction_size(__raw_readw(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_GENERIC_BUG
85 if (__kernel_text_address(instruction_pointer(regs))) {
86 insn_size_t insn = *(insn_size_t *)instruction_pointer(regs);
87 if (insn == TRAPA_BUG_OPCODE)
88 handle_BUG(regs);
89 return;
90 }
91#endif
92
93 force_sig(SIGTRAP, current);
94}
95
96BUILD_TRAP_HANDLER(nmi)
97{
98 unsigned int cpu = smp_processor_id();
99 TRAP_HANDLER_DECL;
100
101 nmi_enter();
102 nmi_count(cpu)++;
103
104 switch (notify_die(DIE_NMI, "NMI", regs, 0, vec & 0xff, SIGINT)) {
105 case NOTIFY_OK:
106 case NOTIFY_STOP:
107 break;
108 case NOTIFY_BAD:
109 die("Fatal Non-Maskable Interrupt", regs, SIGINT);
110 default:
111 printk(KERN_ALERT "Got NMI, but nobody cared. Ignoring...\n");
112 break;
113 }
114
115 nmi_exit();
116}
1#include <linux/bug.h>
2#include <linux/io.h>
3#include <linux/types.h>
4#include <linux/kdebug.h>
5#include <linux/signal.h>
6#include <linux/sched.h>
7#include <linux/uaccess.h>
8#include <linux/hardirq.h>
9#include <asm/unwinder.h>
10#include <asm/system.h>
11
12#ifdef CONFIG_GENERIC_BUG
13static void handle_BUG(struct pt_regs *regs)
14{
15 const struct bug_entry *bug;
16 unsigned long bugaddr = regs->pc;
17 enum bug_trap_type tt;
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);
29 if (tt == BUG_TRAP_TYPE_WARN) {
30 regs->pc += instruction_size(bugaddr);
31 return;
32 }
33
34invalid:
35 die("Kernel BUG", regs, TRAPA_BUG_OPCODE & 0xff);
36}
37
38int is_valid_bugaddr(unsigned long addr)
39{
40 insn_size_t opcode;
41
42 if (addr < PAGE_OFFSET)
43 return 0;
44 if (probe_kernel_address((insn_size_t *)addr, opcode))
45 return 0;
46 if (opcode == TRAPA_BUG_OPCODE)
47 return 1;
48
49 return 0;
50}
51#endif
52
53/*
54 * Generic trap handler.
55 */
56BUILD_TRAP_HANDLER(debug)
57{
58 TRAP_HANDLER_DECL;
59
60 /* Rewind */
61 regs->pc -= instruction_size(__raw_readw(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 */
73BUILD_TRAP_HANDLER(bug)
74{
75 TRAP_HANDLER_DECL;
76
77 /* Rewind */
78 regs->pc -= instruction_size(__raw_readw(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_GENERIC_BUG
85 if (__kernel_text_address(instruction_pointer(regs))) {
86 insn_size_t insn = *(insn_size_t *)instruction_pointer(regs);
87 if (insn == TRAPA_BUG_OPCODE)
88 handle_BUG(regs);
89 return;
90 }
91#endif
92
93 force_sig(SIGTRAP, current);
94}
95
96BUILD_TRAP_HANDLER(nmi)
97{
98 unsigned int cpu = smp_processor_id();
99 TRAP_HANDLER_DECL;
100
101 nmi_enter();
102 nmi_count(cpu)++;
103
104 switch (notify_die(DIE_NMI, "NMI", regs, 0, vec & 0xff, SIGINT)) {
105 case NOTIFY_OK:
106 case NOTIFY_STOP:
107 break;
108 case NOTIFY_BAD:
109 die("Fatal Non-Maskable Interrupt", regs, SIGINT);
110 default:
111 printk(KERN_ALERT "Got NMI, but nobody cared. Ignoring...\n");
112 break;
113 }
114
115 nmi_exit();
116}