1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
|
/*
* Copyright (C) 2012 Regents of the University of California
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation, version 2.
*
* 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.
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/sched.h>
#include <linux/sched/debug.h>
#include <linux/sched/signal.h>
#include <linux/signal.h>
#include <linux/kdebug.h>
#include <linux/uaccess.h>
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/irq.h>
#include <asm/processor.h>
#include <asm/ptrace.h>
#include <asm/csr.h>
int show_unhandled_signals = 1;
extern asmlinkage void handle_exception(void);
static DEFINE_SPINLOCK(die_lock);
void die(struct pt_regs *regs, const char *str)
{
static int die_counter;
int ret;
oops_enter();
spin_lock_irq(&die_lock);
console_verbose();
bust_spinlocks(1);
pr_emerg("%s [#%d]\n", str, ++die_counter);
print_modules();
show_regs(regs);
ret = notify_die(DIE_OOPS, str, regs, 0, regs->scause, SIGSEGV);
bust_spinlocks(0);
add_taint(TAINT_DIE, LOCKDEP_NOW_UNRELIABLE);
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 do_trap(struct pt_regs *regs, int signo, int code,
unsigned long addr, struct task_struct *tsk)
{
if (show_unhandled_signals && unhandled_signal(tsk, signo)
&& printk_ratelimit()) {
pr_info("%s[%d]: unhandled signal %d code 0x%x at 0x" REG_FMT,
tsk->comm, task_pid_nr(tsk), signo, code, addr);
print_vma_addr(KERN_CONT " in ", GET_IP(regs));
pr_cont("\n");
show_regs(regs);
}
force_sig_fault(signo, code, (void __user *)addr, tsk);
}
static void do_trap_error(struct pt_regs *regs, int signo, int code,
unsigned long addr, const char *str)
{
if (user_mode(regs)) {
do_trap(regs, signo, code, addr, current);
} else {
if (!fixup_exception(regs))
die(regs, str);
}
}
#define DO_ERROR_INFO(name, signo, code, str) \
asmlinkage void name(struct pt_regs *regs) \
{ \
do_trap_error(regs, signo, code, regs->sepc, "Oops - " str); \
}
DO_ERROR_INFO(do_trap_unknown,
SIGILL, ILL_ILLTRP, "unknown exception");
DO_ERROR_INFO(do_trap_insn_misaligned,
SIGBUS, BUS_ADRALN, "instruction address misaligned");
DO_ERROR_INFO(do_trap_insn_fault,
SIGSEGV, SEGV_ACCERR, "instruction access fault");
DO_ERROR_INFO(do_trap_insn_illegal,
SIGILL, ILL_ILLOPC, "illegal instruction");
DO_ERROR_INFO(do_trap_load_misaligned,
SIGBUS, BUS_ADRALN, "load address misaligned");
DO_ERROR_INFO(do_trap_load_fault,
SIGSEGV, SEGV_ACCERR, "load access fault");
DO_ERROR_INFO(do_trap_store_misaligned,
SIGBUS, BUS_ADRALN, "store (or AMO) address misaligned");
DO_ERROR_INFO(do_trap_store_fault,
SIGSEGV, SEGV_ACCERR, "store (or AMO) access fault");
DO_ERROR_INFO(do_trap_ecall_u,
SIGILL, ILL_ILLTRP, "environment call from U-mode");
DO_ERROR_INFO(do_trap_ecall_s,
SIGILL, ILL_ILLTRP, "environment call from S-mode");
DO_ERROR_INFO(do_trap_ecall_m,
SIGILL, ILL_ILLTRP, "environment call from M-mode");
asmlinkage void do_trap_break(struct pt_regs *regs)
{
#ifdef CONFIG_GENERIC_BUG
if (!user_mode(regs)) {
enum bug_trap_type type;
type = report_bug(regs->sepc, regs);
switch (type) {
case BUG_TRAP_TYPE_NONE:
break;
case BUG_TRAP_TYPE_WARN:
regs->sepc += sizeof(bug_insn_t);
return;
case BUG_TRAP_TYPE_BUG:
die(regs, "Kernel BUG");
}
}
#endif /* CONFIG_GENERIC_BUG */
force_sig_fault(SIGTRAP, TRAP_BRKPT, (void __user *)(regs->sepc), current);
}
#ifdef CONFIG_GENERIC_BUG
int is_valid_bugaddr(unsigned long pc)
{
bug_insn_t insn;
if (pc < PAGE_OFFSET)
return 0;
if (probe_kernel_address((bug_insn_t *)pc, insn))
return 0;
return (insn == __BUG_INSN);
}
#endif /* CONFIG_GENERIC_BUG */
void __init trap_init(void)
{
/*
* Set sup0 scratch register to 0, indicating to exception vector
* that we are presently executing in the kernel
*/
csr_write(sscratch, 0);
/* Set the exception vector address */
csr_write(stvec, &handle_exception);
/* Enable all interrupts */
csr_write(sie, -1);
}
|
