1 # 1 #
2 # This file contains a few gdb macros (user de 2 # This file contains a few gdb macros (user defined commands) to extract
3 # useful information from kernel crashdump (kd 3 # useful information from kernel crashdump (kdump) like stack traces of
4 # all the processes or a particular process an 4 # all the processes or a particular process and trapinfo.
5 # 5 #
6 # These macros can be used by copying this fil 6 # These macros can be used by copying this file in .gdbinit (put in home
7 # directory or current directory) or by invoki 7 # directory or current directory) or by invoking gdb command with
8 # --command=<command-file-name> option 8 # --command=<command-file-name> option
9 # 9 #
10 # Credits: 10 # Credits:
11 # Alexander Nyberg <alexn@telia.com> 11 # Alexander Nyberg <alexn@telia.com>
12 # V Srivatsa <vatsa@in.ibm.com> 12 # V Srivatsa <vatsa@in.ibm.com>
13 # Maneesh Soni <maneesh@in.ibm.com> 13 # Maneesh Soni <maneesh@in.ibm.com>
14 # 14 #
15 15
16 define bttnobp 16 define bttnobp
17 set $tasks_off=((size_t)&((struct task 17 set $tasks_off=((size_t)&((struct task_struct *)0)->tasks)
18 set $pid_off=((size_t)&((struct task_s 18 set $pid_off=((size_t)&((struct task_struct *)0)->thread_group.next)
19 set $init_t=&init_task 19 set $init_t=&init_task
20 set $next_t=(((char *)($init_t->tasks) 20 set $next_t=(((char *)($init_t->tasks).next) - $tasks_off)
21 set var $stacksize = sizeof(union thre 21 set var $stacksize = sizeof(union thread_union)
22 while ($next_t != $init_t) 22 while ($next_t != $init_t)
23 set $next_t=(struct task_struc 23 set $next_t=(struct task_struct *)$next_t
24 printf "\npid %d; comm %s:\n", 24 printf "\npid %d; comm %s:\n", $next_t.pid, $next_t.comm
25 printf "===================\n" 25 printf "===================\n"
26 set var $stackp = $next_t.thre 26 set var $stackp = $next_t.thread.sp
27 set var $stack_top = ($stackp 27 set var $stack_top = ($stackp & ~($stacksize - 1)) + $stacksize
28 28
29 while ($stackp < $stack_top) 29 while ($stackp < $stack_top)
30 if (*($stackp) > _stex 30 if (*($stackp) > _stext && *($stackp) < _sinittext)
31 info symbol *( 31 info symbol *($stackp)
32 end 32 end
33 set $stackp += 4 33 set $stackp += 4
34 end 34 end
35 set $next_th=(((char *)$next_t 35 set $next_th=(((char *)$next_t->thread_group.next) - $pid_off)
36 while ($next_th != $next_t) 36 while ($next_th != $next_t)
37 set $next_th=(struct t 37 set $next_th=(struct task_struct *)$next_th
38 printf "\npid %d; comm 38 printf "\npid %d; comm %s:\n", $next_t.pid, $next_t.comm
39 printf "============== 39 printf "===================\n"
40 set var $stackp = $nex 40 set var $stackp = $next_t.thread.sp
41 set var $stack_top = ( 41 set var $stack_top = ($stackp & ~($stacksize - 1)) + stacksize
42 42
43 while ($stackp < $stac 43 while ($stackp < $stack_top)
44 if (*($stackp) 44 if (*($stackp) > _stext && *($stackp) < _sinittext)
45 info s 45 info symbol *($stackp)
46 end 46 end
47 set $stackp += 47 set $stackp += 4
48 end 48 end
49 set $next_th=(((char * 49 set $next_th=(((char *)$next_th->thread_group.next) - $pid_off)
50 end 50 end
51 set $next_t=(char *)($next_t-> 51 set $next_t=(char *)($next_t->tasks.next) - $tasks_off
52 end 52 end
53 end 53 end
54 document bttnobp 54 document bttnobp
55 dump all thread stack traces on a kern 55 dump all thread stack traces on a kernel compiled with !CONFIG_FRAME_POINTER
56 end 56 end
57 57
58 define btthreadstack 58 define btthreadstack
59 set var $pid_task = $arg0 59 set var $pid_task = $arg0
60 60
61 printf "\npid %d; comm %s:\n", $pid_ta 61 printf "\npid %d; comm %s:\n", $pid_task.pid, $pid_task.comm
62 printf "task struct: " 62 printf "task struct: "
63 print $pid_task 63 print $pid_task
64 printf "===================\n" 64 printf "===================\n"
65 set var $stackp = $pid_task.thread.sp 65 set var $stackp = $pid_task.thread.sp
66 set var $stacksize = sizeof(union thre 66 set var $stacksize = sizeof(union thread_union)
67 set var $stack_top = ($stackp & ~($sta 67 set var $stack_top = ($stackp & ~($stacksize - 1)) + $stacksize
68 set var $stack_bot = ($stackp & ~($sta 68 set var $stack_bot = ($stackp & ~($stacksize - 1))
69 69
70 set $stackp = *((unsigned long *) $sta 70 set $stackp = *((unsigned long *) $stackp)
71 while (($stackp < $stack_top) && ($sta 71 while (($stackp < $stack_top) && ($stackp > $stack_bot))
72 set var $addr = *(((unsigned l 72 set var $addr = *(((unsigned long *) $stackp) + 1)
73 info symbol $addr 73 info symbol $addr
74 set $stackp = *((unsigned long 74 set $stackp = *((unsigned long *) $stackp)
75 end 75 end
76 end 76 end
77 document btthreadstack 77 document btthreadstack
78 dump a thread stack using the given t 78 dump a thread stack using the given task structure pointer
79 end 79 end
80 80
81 81
82 define btt 82 define btt
83 set $tasks_off=((size_t)&((struct task 83 set $tasks_off=((size_t)&((struct task_struct *)0)->tasks)
84 set $pid_off=((size_t)&((struct task_s 84 set $pid_off=((size_t)&((struct task_struct *)0)->thread_group.next)
85 set $init_t=&init_task 85 set $init_t=&init_task
86 set $next_t=(((char *)($init_t->tasks) 86 set $next_t=(((char *)($init_t->tasks).next) - $tasks_off)
87 while ($next_t != $init_t) 87 while ($next_t != $init_t)
88 set $next_t=(struct task_struc 88 set $next_t=(struct task_struct *)$next_t
89 btthreadstack $next_t 89 btthreadstack $next_t
90 90
91 set $next_th=(((char *)$next_t 91 set $next_th=(((char *)$next_t->thread_group.next) - $pid_off)
92 while ($next_th != $next_t) 92 while ($next_th != $next_t)
93 set $next_th=(struct t 93 set $next_th=(struct task_struct *)$next_th
94 btthreadstack $next_th 94 btthreadstack $next_th
95 set $next_th=(((char * 95 set $next_th=(((char *)$next_th->thread_group.next) - $pid_off)
96 end 96 end
97 set $next_t=(char *)($next_t-> 97 set $next_t=(char *)($next_t->tasks.next) - $tasks_off
98 end 98 end
99 end 99 end
100 document btt 100 document btt
101 dump all thread stack traces on a kern 101 dump all thread stack traces on a kernel compiled with CONFIG_FRAME_POINTER
102 end 102 end
103 103
104 define btpid 104 define btpid
105 set var $pid = $arg0 105 set var $pid = $arg0
106 set $tasks_off=((size_t)&((struct task 106 set $tasks_off=((size_t)&((struct task_struct *)0)->tasks)
107 set $pid_off=((size_t)&((struct task_s 107 set $pid_off=((size_t)&((struct task_struct *)0)->thread_group.next)
108 set $init_t=&init_task 108 set $init_t=&init_task
109 set $next_t=(((char *)($init_t->tasks) 109 set $next_t=(((char *)($init_t->tasks).next) - $tasks_off)
110 set var $pid_task = 0 110 set var $pid_task = 0
111 111
112 while ($next_t != $init_t) 112 while ($next_t != $init_t)
113 set $next_t=(struct task_struc 113 set $next_t=(struct task_struct *)$next_t
114 114
115 if ($next_t.pid == $pid) 115 if ($next_t.pid == $pid)
116 set $pid_task = $next_ 116 set $pid_task = $next_t
117 end 117 end
118 118
119 set $next_th=(((char *)$next_t 119 set $next_th=(((char *)$next_t->thread_group.next) - $pid_off)
120 while ($next_th != $next_t) 120 while ($next_th != $next_t)
121 set $next_th=(struct t 121 set $next_th=(struct task_struct *)$next_th
122 if ($next_th.pid == $p 122 if ($next_th.pid == $pid)
123 set $pid_task 123 set $pid_task = $next_th
124 end 124 end
125 set $next_th=(((char * 125 set $next_th=(((char *)$next_th->thread_group.next) - $pid_off)
126 end 126 end
127 set $next_t=(char *)($next_t-> 127 set $next_t=(char *)($next_t->tasks.next) - $tasks_off
128 end 128 end
129 129
130 btthreadstack $pid_task 130 btthreadstack $pid_task
131 end 131 end
132 document btpid 132 document btpid
133 backtrace of pid 133 backtrace of pid
134 end 134 end
135 135
136 136
137 define trapinfo 137 define trapinfo
138 set var $pid = $arg0 138 set var $pid = $arg0
139 set $tasks_off=((size_t)&((struct task 139 set $tasks_off=((size_t)&((struct task_struct *)0)->tasks)
140 set $pid_off=((size_t)&((struct task_s 140 set $pid_off=((size_t)&((struct task_struct *)0)->thread_group.next)
141 set $init_t=&init_task 141 set $init_t=&init_task
142 set $next_t=(((char *)($init_t->tasks) 142 set $next_t=(((char *)($init_t->tasks).next) - $tasks_off)
143 set var $pid_task = 0 143 set var $pid_task = 0
144 144
145 while ($next_t != $init_t) 145 while ($next_t != $init_t)
146 set $next_t=(struct task_struc 146 set $next_t=(struct task_struct *)$next_t
147 147
148 if ($next_t.pid == $pid) 148 if ($next_t.pid == $pid)
149 set $pid_task = $next_ 149 set $pid_task = $next_t
150 end 150 end
151 151
152 set $next_th=(((char *)$next_t 152 set $next_th=(((char *)$next_t->thread_group.next) - $pid_off)
153 while ($next_th != $next_t) 153 while ($next_th != $next_t)
154 set $next_th=(struct t 154 set $next_th=(struct task_struct *)$next_th
155 if ($next_th.pid == $p 155 if ($next_th.pid == $pid)
156 set $pid_task 156 set $pid_task = $next_th
157 end 157 end
158 set $next_th=(((char * 158 set $next_th=(((char *)$next_th->thread_group.next) - $pid_off)
159 end 159 end
160 set $next_t=(char *)($next_t-> 160 set $next_t=(char *)($next_t->tasks.next) - $tasks_off
161 end 161 end
162 162
163 printf "Trapno %ld, cr2 0x%lx, error_c 163 printf "Trapno %ld, cr2 0x%lx, error_code %ld\n", $pid_task.thread.trap_no, \
164 $pid_task.thre 164 $pid_task.thread.cr2, $pid_task.thread.error_code
165 165
166 end 166 end
167 document trapinfo 167 document trapinfo
168 Run info threads and lookup pid of thr 168 Run info threads and lookup pid of thread #1
169 'trapinfo <pid>' will tell you by whic 169 'trapinfo <pid>' will tell you by which trap & possibly
170 address the kernel panicked. 170 address the kernel panicked.
171 end 171 end
172 172
173 define dump_record 173 define dump_record
174 set var $desc = $arg0 174 set var $desc = $arg0
175 set var $info = $arg1 175 set var $info = $arg1
176 if ($argc > 2) 176 if ($argc > 2)
177 set var $prev_flags = $arg2 177 set var $prev_flags = $arg2
178 else 178 else
179 set var $prev_flags = 0 179 set var $prev_flags = 0
180 end 180 end
181 181
182 set var $prefix = 1 182 set var $prefix = 1
183 set var $newline = 1 183 set var $newline = 1
184 184
185 set var $begin = $desc->text_blk_lpos. 185 set var $begin = $desc->text_blk_lpos.begin % (1U << prb->text_data_ring.size_bits)
186 set var $next = $desc->text_blk_lpos.n 186 set var $next = $desc->text_blk_lpos.next % (1U << prb->text_data_ring.size_bits)
187 187
188 # handle data-less record 188 # handle data-less record
189 if ($begin & 1) 189 if ($begin & 1)
190 set var $text_len = 0 190 set var $text_len = 0
191 set var $log = "" 191 set var $log = ""
192 else 192 else
193 # handle wrapping data block 193 # handle wrapping data block
194 if ($begin > $next) 194 if ($begin > $next)
195 set var $begin = 0 195 set var $begin = 0
196 end 196 end
197 197
198 # skip over descriptor id 198 # skip over descriptor id
199 set var $begin = $begin + size 199 set var $begin = $begin + sizeof(long)
200 200
201 # handle truncated message 201 # handle truncated message
202 if ($next - $begin < $info->te 202 if ($next - $begin < $info->text_len)
203 set var $text_len = $n 203 set var $text_len = $next - $begin
204 else 204 else
205 set var $text_len = $i 205 set var $text_len = $info->text_len
206 end 206 end
207 207
208 set var $log = &prb->text_data 208 set var $log = &prb->text_data_ring.data[$begin]
209 end 209 end
210 210
211 # prev & LOG_CONT && !(info->flags & L 211 # prev & LOG_CONT && !(info->flags & LOG_PREIX)
212 if (($prev_flags & 8) && !($info->flag 212 if (($prev_flags & 8) && !($info->flags & 4))
213 set var $prefix = 0 213 set var $prefix = 0
214 end 214 end
215 215
216 # info->flags & LOG_CONT 216 # info->flags & LOG_CONT
217 if ($info->flags & 8) 217 if ($info->flags & 8)
218 # (prev & LOG_CONT && !(prev & 218 # (prev & LOG_CONT && !(prev & LOG_NEWLINE))
219 if (($prev_flags & 8) && !($pr 219 if (($prev_flags & 8) && !($prev_flags & 2))
220 set var $prefix = 0 220 set var $prefix = 0
221 end 221 end
222 # (!(info->flags & LOG_NEWLINE 222 # (!(info->flags & LOG_NEWLINE))
223 if (!($info->flags & 2)) 223 if (!($info->flags & 2))
224 set var $newline = 0 224 set var $newline = 0
225 end 225 end
226 end 226 end
227 227
228 if ($prefix) 228 if ($prefix)
229 printf "[%5lu.%06lu] ", $info- 229 printf "[%5lu.%06lu] ", $info->ts_nsec / 1000000000, $info->ts_nsec % 1000000000
230 end 230 end
231 if ($text_len) 231 if ($text_len)
232 eval "printf \"%%%d.%ds\", $lo 232 eval "printf \"%%%d.%ds\", $log", $text_len, $text_len
233 end 233 end
234 if ($newline) 234 if ($newline)
235 printf "\n" 235 printf "\n"
236 end 236 end
237 237
238 # handle dictionary data 238 # handle dictionary data
239 239
240 set var $dict = &$info->dev_info.subsy 240 set var $dict = &$info->dev_info.subsystem[0]
241 set var $dict_len = sizeof($info->dev_ 241 set var $dict_len = sizeof($info->dev_info.subsystem)
242 if ($dict[0] != '\0') 242 if ($dict[0] != '\0')
243 printf " SUBSYSTEM=" 243 printf " SUBSYSTEM="
244 set var $idx = 0 244 set var $idx = 0
245 while ($idx < $dict_len) 245 while ($idx < $dict_len)
246 set var $c = $dict[$id 246 set var $c = $dict[$idx]
247 if ($c == '\0') 247 if ($c == '\0')
248 loop_break 248 loop_break
249 else 249 else
250 if ($c < ' ' | 250 if ($c < ' ' || $c >= 127 || $c == '\\')
251 printf 251 printf "\\x%02x", $c
252 else 252 else
253 printf 253 printf "%c", $c
254 end 254 end
255 end 255 end
256 set var $idx = $idx + 256 set var $idx = $idx + 1
257 end 257 end
258 printf "\n" 258 printf "\n"
259 end 259 end
260 260
261 set var $dict = &$info->dev_info.devic 261 set var $dict = &$info->dev_info.device[0]
262 set var $dict_len = sizeof($info->dev_ 262 set var $dict_len = sizeof($info->dev_info.device)
263 if ($dict[0] != '\0') 263 if ($dict[0] != '\0')
264 printf " DEVICE=" 264 printf " DEVICE="
265 set var $idx = 0 265 set var $idx = 0
266 while ($idx < $dict_len) 266 while ($idx < $dict_len)
267 set var $c = $dict[$id 267 set var $c = $dict[$idx]
268 if ($c == '\0') 268 if ($c == '\0')
269 loop_break 269 loop_break
270 else 270 else
271 if ($c < ' ' | 271 if ($c < ' ' || $c >= 127 || $c == '\\')
272 printf 272 printf "\\x%02x", $c
273 else 273 else
274 printf 274 printf "%c", $c
275 end 275 end
276 end 276 end
277 set var $idx = $idx + 277 set var $idx = $idx + 1
278 end 278 end
279 printf "\n" 279 printf "\n"
280 end 280 end
281 end 281 end
282 document dump_record 282 document dump_record
283 Dump a single record. The first parame 283 Dump a single record. The first parameter is the descriptor,
284 the second parameter is the info, the 284 the second parameter is the info, the third parameter is
285 optional and specifies the previous re 285 optional and specifies the previous record's flags, used for
286 properly formatting continued lines. 286 properly formatting continued lines.
287 end 287 end
288 288
289 define dmesg 289 define dmesg
290 # definitions from kernel/printk/print 290 # definitions from kernel/printk/printk_ringbuffer.h
291 set var $desc_committed = 1 291 set var $desc_committed = 1
292 set var $desc_finalized = 2 292 set var $desc_finalized = 2
293 set var $desc_sv_bits = sizeof(long) * 293 set var $desc_sv_bits = sizeof(long) * 8
294 set var $desc_flags_shift = $desc_sv_b 294 set var $desc_flags_shift = $desc_sv_bits - 2
295 set var $desc_flags_mask = 3 << $desc_ 295 set var $desc_flags_mask = 3 << $desc_flags_shift
296 set var $id_mask = ~$desc_flags_mask 296 set var $id_mask = ~$desc_flags_mask
297 297
298 set var $desc_count = 1U << prb->desc_ 298 set var $desc_count = 1U << prb->desc_ring.count_bits
299 set var $prev_flags = 0 299 set var $prev_flags = 0
300 300
301 set var $id = prb->desc_ring.tail_id.c 301 set var $id = prb->desc_ring.tail_id.counter
302 set var $end_id = prb->desc_ring.head_ 302 set var $end_id = prb->desc_ring.head_id.counter
303 303
304 while (1) 304 while (1)
305 set var $desc = &prb->desc_rin 305 set var $desc = &prb->desc_ring.descs[$id % $desc_count]
306 set var $info = &prb->desc_rin 306 set var $info = &prb->desc_ring.infos[$id % $desc_count]
307 307
308 # skip non-committed record 308 # skip non-committed record
309 set var $state = 3 & ($desc->s 309 set var $state = 3 & ($desc->state_var.counter >> $desc_flags_shift)
310 if ($state == $desc_committed 310 if ($state == $desc_committed || $state == $desc_finalized)
311 dump_record $desc $inf 311 dump_record $desc $info $prev_flags
312 set var $prev_flags = 312 set var $prev_flags = $info->flags
313 end 313 end
314 314
315 if ($id == $end_id) 315 if ($id == $end_id)
316 loop_break 316 loop_break
317 end 317 end
318 set var $id = ($id + 1) & $id_ 318 set var $id = ($id + 1) & $id_mask
319 end 319 end
320 end 320 end
321 document dmesg 321 document dmesg
322 print the kernel ring buffer 322 print the kernel ring buffer
323 end 323 end
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