Root/
1 | /* Rewritten by Rusty Russell, on the backs of many others... |
2 | Copyright (C) 2001 Rusty Russell, 2002 Rusty Russell IBM. |
3 | |
4 | This program is free software; you can redistribute it and/or modify |
5 | it under the terms of the GNU General Public License as published by |
6 | the Free Software Foundation; either version 2 of the License, or |
7 | (at your option) any later version. |
8 | |
9 | This program is distributed in the hope that it will be useful, |
10 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
11 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
12 | GNU General Public License for more details. |
13 | |
14 | You should have received a copy of the GNU General Public License |
15 | along with this program; if not, write to the Free Software |
16 | Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
17 | */ |
18 | #include <linux/ftrace.h> |
19 | #include <linux/memory.h> |
20 | #include <linux/module.h> |
21 | #include <linux/mutex.h> |
22 | #include <linux/init.h> |
23 | |
24 | #include <asm/sections.h> |
25 | #include <asm/uaccess.h> |
26 | |
27 | /* |
28 | * mutex protecting text section modification (dynamic code patching). |
29 | * some users need to sleep (allocating memory...) while they hold this lock. |
30 | * |
31 | * NOT exported to modules - patching kernel text is a really delicate matter. |
32 | */ |
33 | DEFINE_MUTEX(text_mutex); |
34 | |
35 | extern struct exception_table_entry __start___ex_table[]; |
36 | extern struct exception_table_entry __stop___ex_table[]; |
37 | |
38 | /* Sort the kernel's built-in exception table */ |
39 | void __init sort_main_extable(void) |
40 | { |
41 | sort_extable(__start___ex_table, __stop___ex_table); |
42 | } |
43 | |
44 | /* Given an address, look for it in the exception tables. */ |
45 | const struct exception_table_entry *search_exception_tables(unsigned long addr) |
46 | { |
47 | const struct exception_table_entry *e; |
48 | |
49 | e = search_extable(__start___ex_table, __stop___ex_table-1, addr); |
50 | if (!e) |
51 | e = search_module_extables(addr); |
52 | return e; |
53 | } |
54 | |
55 | static inline int init_kernel_text(unsigned long addr) |
56 | { |
57 | if (addr >= (unsigned long)_sinittext && |
58 | addr <= (unsigned long)_einittext) |
59 | return 1; |
60 | return 0; |
61 | } |
62 | |
63 | int core_kernel_text(unsigned long addr) |
64 | { |
65 | if (addr >= (unsigned long)_stext && |
66 | addr <= (unsigned long)_etext) |
67 | return 1; |
68 | |
69 | if (system_state == SYSTEM_BOOTING && |
70 | init_kernel_text(addr)) |
71 | return 1; |
72 | return 0; |
73 | } |
74 | |
75 | int __kernel_text_address(unsigned long addr) |
76 | { |
77 | if (core_kernel_text(addr)) |
78 | return 1; |
79 | if (is_module_text_address(addr)) |
80 | return 1; |
81 | /* |
82 | * There might be init symbols in saved stacktraces. |
83 | * Give those symbols a chance to be printed in |
84 | * backtraces (such as lockdep traces). |
85 | * |
86 | * Since we are after the module-symbols check, there's |
87 | * no danger of address overlap: |
88 | */ |
89 | if (init_kernel_text(addr)) |
90 | return 1; |
91 | return 0; |
92 | } |
93 | |
94 | int kernel_text_address(unsigned long addr) |
95 | { |
96 | if (core_kernel_text(addr)) |
97 | return 1; |
98 | return is_module_text_address(addr); |
99 | } |
100 | |
101 | /* |
102 | * On some architectures (PPC64, IA64) function pointers |
103 | * are actually only tokens to some data that then holds the |
104 | * real function address. As a result, to find if a function |
105 | * pointer is part of the kernel text, we need to do some |
106 | * special dereferencing first. |
107 | */ |
108 | int func_ptr_is_kernel_text(void *ptr) |
109 | { |
110 | unsigned long addr; |
111 | addr = (unsigned long) dereference_function_descriptor(ptr); |
112 | if (core_kernel_text(addr)) |
113 | return 1; |
114 | return is_module_text_address(addr); |
115 | } |
116 |
Branches:
ben-wpan
ben-wpan-stefan
javiroman/ks7010
jz-2.6.34
jz-2.6.34-rc5
jz-2.6.34-rc6
jz-2.6.34-rc7
jz-2.6.35
jz-2.6.36
jz-2.6.37
jz-2.6.38
jz-2.6.39
jz-3.0
jz-3.1
jz-3.11
jz-3.12
jz-3.13
jz-3.15
jz-3.16
jz-3.18-dt
jz-3.2
jz-3.3
jz-3.4
jz-3.5
jz-3.6
jz-3.6-rc2-pwm
jz-3.9
jz-3.9-clk
jz-3.9-rc8
jz47xx
jz47xx-2.6.38
master
Tags:
od-2011-09-04
od-2011-09-18
v2.6.34-rc5
v2.6.34-rc6
v2.6.34-rc7
v3.9