1 /*
2 * kgdbts is a test suite for kgdb for the sole purpose of validating
3 * that key pieces of the kgdb internals are working properly such as
4 * HW/SW breakpoints, single stepping, and NMI.
5 *
6 * Created by: Jason Wessel <jason.wessel@windriver.com>
7 *
8 * Copyright (c) 2008 Wind River Systems, Inc.
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License version 2 as
12 * published by the Free Software Foundation.
13 *
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
17 * See the GNU General Public License for more details.
18 *
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
22 */
23 /* Information about the kgdb test suite.
24 * -------------------------------------
25 *
26 * The kgdb test suite is designed as a KGDB I/O module which
27 * simulates the communications that a debugger would have with kgdb.
28 * The tests are broken up in to a line by line and referenced here as
29 * a "get" which is kgdb requesting input and "put" which is kgdb
30 * sending a response.
31 *
32 * The kgdb suite can be invoked from the kernel command line
33 * arguments system or executed dynamically at run time. The test
34 * suite uses the variable "kgdbts" to obtain the information about
35 * which tests to run and to configure the verbosity level. The
36 * following are the various characters you can use with the kgdbts=
37 * line:
38 *
39 * When using the "kgdbts=" you only choose one of the following core
40 * test types:
41 * A = Run all the core tests silently
42 * V1 = Run all the core tests with minimal output
43 * V2 = Run all the core tests in debug mode
44 *
45 * You can also specify optional tests:
46 * N## = Go to sleep with interrupts of for ## seconds
47 * to test the HW NMI watchdog
48 * F## = Break at do_fork for ## iterations
49 * S## = Break at sys_open for ## iterations
50 * I## = Run the single step test ## iterations
51 *
52 * NOTE: that the do_fork and sys_open tests are mutually exclusive.
53 *
54 * To invoke the kgdb test suite from boot you use a kernel start
55 * argument as follows:
56 * kgdbts=V1 kgdbwait
57 * Or if you wanted to perform the NMI test for 6 seconds and do_fork
58 * test for 100 forks, you could use:
59 * kgdbts=V1N6F100 kgdbwait
60 *
61 * The test suite can also be invoked at run time with:
62 * echo kgdbts=V1N6F100 > /sys/module/kgdbts/parameters/kgdbts
63 * Or as another example:
64 * echo kgdbts=V2 > /sys/module/kgdbts/parameters/kgdbts
65 *
66 * When developing a new kgdb arch specific implementation or
67 * using these tests for the purpose of regression testing,
68 * several invocations are required.
69 *
70 * 1) Boot with the test suite enabled by using the kernel arguments
71 * "kgdbts=V1F100 kgdbwait"
72 * ## If kgdb arch specific implementation has NMI use
73 * "kgdbts=V1N6F100
74 *
75 * 2) After the system boot run the basic test.
76 * echo kgdbts=V1 > /sys/module/kgdbts/parameters/kgdbts
77 *
78 * 3) Run the concurrency tests. It is best to use n+1
79 * while loops where n is the number of cpus you have
80 * in your system. The example below uses only two
81 * loops.
82 *
83 * ## This tests break points on sys_open
84 * while [ 1 ] ; do find / > /dev/null 2>&1 ; done &
85 * while [ 1 ] ; do find / > /dev/null 2>&1 ; done &
86 * echo kgdbts=V1S10000 > /sys/module/kgdbts/parameters/kgdbts
87 * fg # and hit control-c
88 * fg # and hit control-c
89 * ## This tests break points on do_fork
90 * while [ 1 ] ; do date > /dev/null ; done &
91 * while [ 1 ] ; do date > /dev/null ; done &
92 * echo kgdbts=V1F1000 > /sys/module/kgdbts/parameters/kgdbts
93 * fg # and hit control-c
94 *
95 */
96
97 #include <linux/kernel.h>
98 #include <linux/kgdb.h>
99 #include <linux/ctype.h>
100 #include <linux/uaccess.h>
101 #include <linux/syscalls.h>
102 #include <linux/nmi.h>
103 #include <linux/delay.h>
104 #include <linux/kthread.h>
105 #include <linux/module.h>
106 #include <asm/sections.h>
107
108 #define v1printk(a...) do { \
109 if (verbose) \
110 printk(KERN_INFO a); \
111 } while (0)
112 #define v2printk(a...) do { \
113 if (verbose > 1) { \
114 printk(KERN_INFO a); \
115 } \
116 touch_nmi_watchdog(); \
117 } while (0)
118 #define eprintk(a...) do { \
119 printk(KERN_ERR a); \
120 WARN_ON(1); \
121 } while (0)
122 #define MAX_CONFIG_LEN 40
123
124 static struct kgdb_io kgdbts_io_ops;
125 static char get_buf[BUFMAX];
126 static int get_buf_cnt;
127 static char put_buf[BUFMAX];
128 static int put_buf_cnt;
129 static char scratch_buf[BUFMAX];
130 static int verbose;
131 static int repeat_test;
132 static int test_complete;
133 static int send_ack;
134 static int final_ack;
135 static int force_hwbrks;
136 static int hwbreaks_ok;
137 static int hw_break_val;
138 static int hw_break_val2;
139 static int cont_instead_of_sstep;
140 static unsigned long cont_thread_id;
141 static unsigned long sstep_thread_id;
142 #if defined(CONFIG_ARM) || defined(CONFIG_MIPS) || defined(CONFIG_SPARC)
143 static int arch_needs_sstep_emulation = 1;
144 #else
145 static int arch_needs_sstep_emulation;
146 #endif
147 static unsigned long cont_addr;
148 static unsigned long sstep_addr;
149 static int restart_from_top_after_write;
150 static int sstep_state;
151
152 /* Storage for the registers, in GDB format. */
153 static unsigned long kgdbts_gdb_regs[(NUMREGBYTES +
154 sizeof(unsigned long) - 1) /
155 sizeof(unsigned long)];
156 static struct pt_regs kgdbts_regs;
157
158 /* -1 = init not run yet, 0 = unconfigured, 1 = configured. */
159 static int configured = -1;
160
161 #ifdef CONFIG_KGDB_TESTS_BOOT_STRING
162 static char config[MAX_CONFIG_LEN] = CONFIG_KGDB_TESTS_BOOT_STRING;
163 #else
164 static char config[MAX_CONFIG_LEN];
165 #endif
166 static struct kparam_string kps = {
167 .string = config,
168 .maxlen = MAX_CONFIG_LEN,
169 };
170
171 static void fill_get_buf(char *buf);
172
173 struct test_struct {
174 char *get;
175 char *put;
176 void (*get_handler)(char *);
177 int (*put_handler)(char *, char *);
178 };
179
180 struct test_state {
181 char *name;
182 struct test_struct *tst;
183 int idx;
184 int (*run_test) (int, int);
185 int (*validate_put) (char *);
186 };
187
188 static struct test_state ts;
189
kgdbts_unreg_thread(void * ptr)190 static int kgdbts_unreg_thread(void *ptr)
191 {
192 /* Wait until the tests are complete and then ungresiter the I/O
193 * driver.
194 */
195 while (!final_ack)
196 msleep_interruptible(1500);
197 /* Pause for any other threads to exit after final ack. */
198 msleep_interruptible(1000);
199 if (configured)
200 kgdb_unregister_io_module(&kgdbts_io_ops);
201 configured = 0;
202
203 return 0;
204 }
205
206 /* This is noinline such that it can be used for a single location to
207 * place a breakpoint
208 */
kgdbts_break_test(void)209 static noinline void kgdbts_break_test(void)
210 {
211 v2printk("kgdbts: breakpoint complete\n");
212 }
213
214 /* Lookup symbol info in the kernel */
lookup_addr(char * arg)215 static unsigned long lookup_addr(char *arg)
216 {
217 unsigned long addr = 0;
218
219 if (!strcmp(arg, "kgdbts_break_test"))
220 addr = (unsigned long)kgdbts_break_test;
221 else if (!strcmp(arg, "sys_open"))
222 addr = (unsigned long)do_sys_open;
223 else if (!strcmp(arg, "do_fork"))
224 addr = (unsigned long)_do_fork;
225 else if (!strcmp(arg, "hw_break_val"))
226 addr = (unsigned long)&hw_break_val;
227 addr = (unsigned long) dereference_function_descriptor((void *)addr);
228 return addr;
229 }
230
break_helper(char * bp_type,char * arg,unsigned long vaddr)231 static void break_helper(char *bp_type, char *arg, unsigned long vaddr)
232 {
233 unsigned long addr;
234
235 if (arg)
236 addr = lookup_addr(arg);
237 else
238 addr = vaddr;
239
240 sprintf(scratch_buf, "%s,%lx,%i", bp_type, addr,
241 BREAK_INSTR_SIZE);
242 fill_get_buf(scratch_buf);
243 }
244
sw_break(char * arg)245 static void sw_break(char *arg)
246 {
247 break_helper(force_hwbrks ? "Z1" : "Z0", arg, 0);
248 }
249
sw_rem_break(char * arg)250 static void sw_rem_break(char *arg)
251 {
252 break_helper(force_hwbrks ? "z1" : "z0", arg, 0);
253 }
254
hw_break(char * arg)255 static void hw_break(char *arg)
256 {
257 break_helper("Z1", arg, 0);
258 }
259
hw_rem_break(char * arg)260 static void hw_rem_break(char *arg)
261 {
262 break_helper("z1", arg, 0);
263 }
264
hw_write_break(char * arg)265 static void hw_write_break(char *arg)
266 {
267 break_helper("Z2", arg, 0);
268 }
269
hw_rem_write_break(char * arg)270 static void hw_rem_write_break(char *arg)
271 {
272 break_helper("z2", arg, 0);
273 }
274
hw_access_break(char * arg)275 static void hw_access_break(char *arg)
276 {
277 break_helper("Z4", arg, 0);
278 }
279
hw_rem_access_break(char * arg)280 static void hw_rem_access_break(char *arg)
281 {
282 break_helper("z4", arg, 0);
283 }
284
hw_break_val_access(void)285 static void hw_break_val_access(void)
286 {
287 hw_break_val2 = hw_break_val;
288 }
289
hw_break_val_write(void)290 static void hw_break_val_write(void)
291 {
292 hw_break_val++;
293 }
294
get_thread_id_continue(char * put_str,char * arg)295 static int get_thread_id_continue(char *put_str, char *arg)
296 {
297 char *ptr = &put_str[11];
298
299 if (put_str[1] != 'T' || put_str[2] != '0')
300 return 1;
301 kgdb_hex2long(&ptr, &cont_thread_id);
302 return 0;
303 }
304
check_and_rewind_pc(char * put_str,char * arg)305 static int check_and_rewind_pc(char *put_str, char *arg)
306 {
307 unsigned long addr = lookup_addr(arg);
308 unsigned long ip;
309 int offset = 0;
310
311 kgdb_hex2mem(&put_str[1], (char *)kgdbts_gdb_regs,
312 NUMREGBYTES);
313 gdb_regs_to_pt_regs(kgdbts_gdb_regs, &kgdbts_regs);
314 ip = instruction_pointer(&kgdbts_regs);
315 v2printk("Stopped at IP: %lx\n", ip);
316 #ifdef GDB_ADJUSTS_BREAK_OFFSET
317 /* On some arches, a breakpoint stop requires it to be decremented */
318 if (addr + BREAK_INSTR_SIZE == ip)
319 offset = -BREAK_INSTR_SIZE;
320 #endif
321
322 if (arch_needs_sstep_emulation && sstep_addr &&
323 ip + offset == sstep_addr &&
324 ((!strcmp(arg, "sys_open") || !strcmp(arg, "do_fork")))) {
325 /* This is special case for emulated single step */
326 v2printk("Emul: rewind hit single step bp\n");
327 restart_from_top_after_write = 1;
328 } else if (strcmp(arg, "silent") && ip + offset != addr) {
329 eprintk("kgdbts: BP mismatch %lx expected %lx\n",
330 ip + offset, addr);
331 return 1;
332 }
333 /* Readjust the instruction pointer if needed */
334 ip += offset;
335 cont_addr = ip;
336 #ifdef GDB_ADJUSTS_BREAK_OFFSET
337 instruction_pointer_set(&kgdbts_regs, ip);
338 #endif
339 return 0;
340 }
341
check_single_step(char * put_str,char * arg)342 static int check_single_step(char *put_str, char *arg)
343 {
344 unsigned long addr = lookup_addr(arg);
345 static int matched_id;
346
347 /*
348 * From an arch indepent point of view the instruction pointer
349 * should be on a different instruction
350 */
351 kgdb_hex2mem(&put_str[1], (char *)kgdbts_gdb_regs,
352 NUMREGBYTES);
353 gdb_regs_to_pt_regs(kgdbts_gdb_regs, &kgdbts_regs);
354 v2printk("Singlestep stopped at IP: %lx\n",
355 instruction_pointer(&kgdbts_regs));
356
357 if (sstep_thread_id != cont_thread_id) {
358 /*
359 * Ensure we stopped in the same thread id as before, else the
360 * debugger should continue until the original thread that was
361 * single stepped is scheduled again, emulating gdb's behavior.
362 */
363 v2printk("ThrID does not match: %lx\n", cont_thread_id);
364 if (arch_needs_sstep_emulation) {
365 if (matched_id &&
366 instruction_pointer(&kgdbts_regs) != addr)
367 goto continue_test;
368 matched_id++;
369 ts.idx -= 2;
370 sstep_state = 0;
371 return 0;
372 }
373 cont_instead_of_sstep = 1;
374 ts.idx -= 4;
375 return 0;
376 }
377 continue_test:
378 matched_id = 0;
379 if (instruction_pointer(&kgdbts_regs) == addr) {
380 eprintk("kgdbts: SingleStep failed at %lx\n",
381 instruction_pointer(&kgdbts_regs));
382 return 1;
383 }
384
385 return 0;
386 }
387
write_regs(char * arg)388 static void write_regs(char *arg)
389 {
390 memset(scratch_buf, 0, sizeof(scratch_buf));
391 scratch_buf[0] = 'G';
392 pt_regs_to_gdb_regs(kgdbts_gdb_regs, &kgdbts_regs);
393 kgdb_mem2hex((char *)kgdbts_gdb_regs, &scratch_buf[1], NUMREGBYTES);
394 fill_get_buf(scratch_buf);
395 }
396
skip_back_repeat_test(char * arg)397 static void skip_back_repeat_test(char *arg)
398 {
399 int go_back = simple_strtol(arg, NULL, 10);
400
401 repeat_test--;
402 if (repeat_test <= 0)
403 ts.idx++;
404 else
405 ts.idx -= go_back;
406 fill_get_buf(ts.tst[ts.idx].get);
407 }
408
got_break(char * put_str,char * arg)409 static int got_break(char *put_str, char *arg)
410 {
411 test_complete = 1;
412 if (!strncmp(put_str+1, arg, 2)) {
413 if (!strncmp(arg, "T0", 2))
414 test_complete = 2;
415 return 0;
416 }
417 return 1;
418 }
419
get_cont_catch(char * arg)420 static void get_cont_catch(char *arg)
421 {
422 /* Always send detach because the test is completed at this point */
423 fill_get_buf("D");
424 }
425
put_cont_catch(char * put_str,char * arg)426 static int put_cont_catch(char *put_str, char *arg)
427 {
428 /* This is at the end of the test and we catch any and all input */
429 v2printk("kgdbts: cleanup task: %lx\n", sstep_thread_id);
430 ts.idx--;
431 return 0;
432 }
433
emul_reset(char * put_str,char * arg)434 static int emul_reset(char *put_str, char *arg)
435 {
436 if (strncmp(put_str, "$OK", 3))
437 return 1;
438 if (restart_from_top_after_write) {
439 restart_from_top_after_write = 0;
440 ts.idx = -1;
441 }
442 return 0;
443 }
444
emul_sstep_get(char * arg)445 static void emul_sstep_get(char *arg)
446 {
447 if (!arch_needs_sstep_emulation) {
448 if (cont_instead_of_sstep) {
449 cont_instead_of_sstep = 0;
450 fill_get_buf("c");
451 } else {
452 fill_get_buf(arg);
453 }
454 return;
455 }
456 switch (sstep_state) {
457 case 0:
458 v2printk("Emulate single step\n");
459 /* Start by looking at the current PC */
460 fill_get_buf("g");
461 break;
462 case 1:
463 /* set breakpoint */
464 break_helper("Z0", NULL, sstep_addr);
465 break;
466 case 2:
467 /* Continue */
468 fill_get_buf("c");
469 break;
470 case 3:
471 /* Clear breakpoint */
472 break_helper("z0", NULL, sstep_addr);
473 break;
474 default:
475 eprintk("kgdbts: ERROR failed sstep get emulation\n");
476 }
477 sstep_state++;
478 }
479
emul_sstep_put(char * put_str,char * arg)480 static int emul_sstep_put(char *put_str, char *arg)
481 {
482 if (!arch_needs_sstep_emulation) {
483 char *ptr = &put_str[11];
484 if (put_str[1] != 'T' || put_str[2] != '0')
485 return 1;
486 kgdb_hex2long(&ptr, &sstep_thread_id);
487 return 0;
488 }
489 switch (sstep_state) {
490 case 1:
491 /* validate the "g" packet to get the IP */
492 kgdb_hex2mem(&put_str[1], (char *)kgdbts_gdb_regs,
493 NUMREGBYTES);
494 gdb_regs_to_pt_regs(kgdbts_gdb_regs, &kgdbts_regs);
495 v2printk("Stopped at IP: %lx\n",
496 instruction_pointer(&kgdbts_regs));
497 /* Want to stop at IP + break instruction size by default */
498 sstep_addr = cont_addr + BREAK_INSTR_SIZE;
499 break;
500 case 2:
501 if (strncmp(put_str, "$OK", 3)) {
502 eprintk("kgdbts: failed sstep break set\n");
503 return 1;
504 }
505 break;
506 case 3:
507 if (strncmp(put_str, "$T0", 3)) {
508 eprintk("kgdbts: failed continue sstep\n");
509 return 1;
510 } else {
511 char *ptr = &put_str[11];
512 kgdb_hex2long(&ptr, &sstep_thread_id);
513 }
514 break;
515 case 4:
516 if (strncmp(put_str, "$OK", 3)) {
517 eprintk("kgdbts: failed sstep break unset\n");
518 return 1;
519 }
520 /* Single step is complete so continue on! */
521 sstep_state = 0;
522 return 0;
523 default:
524 eprintk("kgdbts: ERROR failed sstep put emulation\n");
525 }
526
527 /* Continue on the same test line until emulation is complete */
528 ts.idx--;
529 return 0;
530 }
531
final_ack_set(char * put_str,char * arg)532 static int final_ack_set(char *put_str, char *arg)
533 {
534 if (strncmp(put_str+1, arg, 2))
535 return 1;
536 final_ack = 1;
537 return 0;
538 }
539 /*
540 * Test to plant a breakpoint and detach, which should clear out the
541 * breakpoint and restore the original instruction.
542 */
543 static struct test_struct plant_and_detach_test[] = {
544 { "?", "S0*" }, /* Clear break points */
545 { "kgdbts_break_test", "OK", sw_break, }, /* set sw breakpoint */
546 { "D", "OK" }, /* Detach */
547 { "", "" },
548 };
549
550 /*
551 * Simple test to write in a software breakpoint, check for the
552 * correct stop location and detach.
553 */
554 static struct test_struct sw_breakpoint_test[] = {
555 { "?", "S0*" }, /* Clear break points */
556 { "kgdbts_break_test", "OK", sw_break, }, /* set sw breakpoint */
557 { "c", "T0*", }, /* Continue */
558 { "g", "kgdbts_break_test", NULL, check_and_rewind_pc },
559 { "write", "OK", write_regs },
560 { "kgdbts_break_test", "OK", sw_rem_break }, /*remove breakpoint */
561 { "D", "OK" }, /* Detach */
562 { "D", "OK", NULL, got_break }, /* On success we made it here */
563 { "", "" },
564 };
565
566 /*
567 * Test a known bad memory read location to test the fault handler and
568 * read bytes 1-8 at the bad address
569 */
570 static struct test_struct bad_read_test[] = {
571 { "?", "S0*" }, /* Clear break points */
572 { "m0,1", "E*" }, /* read 1 byte at address 1 */
573 { "m0,2", "E*" }, /* read 1 byte at address 2 */
574 { "m0,3", "E*" }, /* read 1 byte at address 3 */
575 { "m0,4", "E*" }, /* read 1 byte at address 4 */
576 { "m0,5", "E*" }, /* read 1 byte at address 5 */
577 { "m0,6", "E*" }, /* read 1 byte at address 6 */
578 { "m0,7", "E*" }, /* read 1 byte at address 7 */
579 { "m0,8", "E*" }, /* read 1 byte at address 8 */
580 { "D", "OK" }, /* Detach which removes all breakpoints and continues */
581 { "", "" },
582 };
583
584 /*
585 * Test for hitting a breakpoint, remove it, single step, plant it
586 * again and detach.
587 */
588 static struct test_struct singlestep_break_test[] = {
589 { "?", "S0*" }, /* Clear break points */
590 { "kgdbts_break_test", "OK", sw_break, }, /* set sw breakpoint */
591 { "c", "T0*", NULL, get_thread_id_continue }, /* Continue */
592 { "kgdbts_break_test", "OK", sw_rem_break }, /*remove breakpoint */
593 { "g", "kgdbts_break_test", NULL, check_and_rewind_pc },
594 { "write", "OK", write_regs }, /* Write registers */
595 { "s", "T0*", emul_sstep_get, emul_sstep_put }, /* Single step */
596 { "g", "kgdbts_break_test", NULL, check_single_step },
597 { "kgdbts_break_test", "OK", sw_break, }, /* set sw breakpoint */
598 { "c", "T0*", }, /* Continue */
599 { "g", "kgdbts_break_test", NULL, check_and_rewind_pc },
600 { "write", "OK", write_regs }, /* Write registers */
601 { "D", "OK" }, /* Remove all breakpoints and continues */
602 { "", "" },
603 };
604
605 /*
606 * Test for hitting a breakpoint at do_fork for what ever the number
607 * of iterations required by the variable repeat_test.
608 */
609 static struct test_struct do_fork_test[] = {
610 { "?", "S0*" }, /* Clear break points */
611 { "do_fork", "OK", sw_break, }, /* set sw breakpoint */
612 { "c", "T0*", NULL, get_thread_id_continue }, /* Continue */
613 { "do_fork", "OK", sw_rem_break }, /*remove breakpoint */
614 { "g", "do_fork", NULL, check_and_rewind_pc }, /* check location */
615 { "write", "OK", write_regs, emul_reset }, /* Write registers */
616 { "s", "T0*", emul_sstep_get, emul_sstep_put }, /* Single step */
617 { "g", "do_fork", NULL, check_single_step },
618 { "do_fork", "OK", sw_break, }, /* set sw breakpoint */
619 { "7", "T0*", skip_back_repeat_test }, /* Loop based on repeat_test */
620 { "D", "OK", NULL, final_ack_set }, /* detach and unregister I/O */
621 { "", "", get_cont_catch, put_cont_catch },
622 };
623
624 /* Test for hitting a breakpoint at sys_open for what ever the number
625 * of iterations required by the variable repeat_test.
626 */
627 static struct test_struct sys_open_test[] = {
628 { "?", "S0*" }, /* Clear break points */
629 { "sys_open", "OK", sw_break, }, /* set sw breakpoint */
630 { "c", "T0*", NULL, get_thread_id_continue }, /* Continue */
631 { "sys_open", "OK", sw_rem_break }, /*remove breakpoint */
632 { "g", "sys_open", NULL, check_and_rewind_pc }, /* check location */
633 { "write", "OK", write_regs, emul_reset }, /* Write registers */
634 { "s", "T0*", emul_sstep_get, emul_sstep_put }, /* Single step */
635 { "g", "sys_open", NULL, check_single_step },
636 { "sys_open", "OK", sw_break, }, /* set sw breakpoint */
637 { "7", "T0*", skip_back_repeat_test }, /* Loop based on repeat_test */
638 { "D", "OK", NULL, final_ack_set }, /* detach and unregister I/O */
639 { "", "", get_cont_catch, put_cont_catch },
640 };
641
642 /*
643 * Test for hitting a simple hw breakpoint
644 */
645 static struct test_struct hw_breakpoint_test[] = {
646 { "?", "S0*" }, /* Clear break points */
647 { "kgdbts_break_test", "OK", hw_break, }, /* set hw breakpoint */
648 { "c", "T0*", }, /* Continue */
649 { "g", "kgdbts_break_test", NULL, check_and_rewind_pc },
650 { "write", "OK", write_regs },
651 { "kgdbts_break_test", "OK", hw_rem_break }, /*remove breakpoint */
652 { "D", "OK" }, /* Detach */
653 { "D", "OK", NULL, got_break }, /* On success we made it here */
654 { "", "" },
655 };
656
657 /*
658 * Test for hitting a hw write breakpoint
659 */
660 static struct test_struct hw_write_break_test[] = {
661 { "?", "S0*" }, /* Clear break points */
662 { "hw_break_val", "OK", hw_write_break, }, /* set hw breakpoint */
663 { "c", "T0*", NULL, got_break }, /* Continue */
664 { "g", "silent", NULL, check_and_rewind_pc },
665 { "write", "OK", write_regs },
666 { "hw_break_val", "OK", hw_rem_write_break }, /*remove breakpoint */
667 { "D", "OK" }, /* Detach */
668 { "D", "OK", NULL, got_break }, /* On success we made it here */
669 { "", "" },
670 };
671
672 /*
673 * Test for hitting a hw access breakpoint
674 */
675 static struct test_struct hw_access_break_test[] = {
676 { "?", "S0*" }, /* Clear break points */
677 { "hw_break_val", "OK", hw_access_break, }, /* set hw breakpoint */
678 { "c", "T0*", NULL, got_break }, /* Continue */
679 { "g", "silent", NULL, check_and_rewind_pc },
680 { "write", "OK", write_regs },
681 { "hw_break_val", "OK", hw_rem_access_break }, /*remove breakpoint */
682 { "D", "OK" }, /* Detach */
683 { "D", "OK", NULL, got_break }, /* On success we made it here */
684 { "", "" },
685 };
686
687 /*
688 * Test for hitting a hw access breakpoint
689 */
690 static struct test_struct nmi_sleep_test[] = {
691 { "?", "S0*" }, /* Clear break points */
692 { "c", "T0*", NULL, got_break }, /* Continue */
693 { "D", "OK" }, /* Detach */
694 { "D", "OK", NULL, got_break }, /* On success we made it here */
695 { "", "" },
696 };
697
fill_get_buf(char * buf)698 static void fill_get_buf(char *buf)
699 {
700 unsigned char checksum = 0;
701 int count = 0;
702 char ch;
703
704 strcpy(get_buf, "$");
705 strcat(get_buf, buf);
706 while ((ch = buf[count])) {
707 checksum += ch;
708 count++;
709 }
710 strcat(get_buf, "#");
711 get_buf[count + 2] = hex_asc_hi(checksum);
712 get_buf[count + 3] = hex_asc_lo(checksum);
713 get_buf[count + 4] = '\0';
714 v2printk("get%i: %s\n", ts.idx, get_buf);
715 }
716
validate_simple_test(char * put_str)717 static int validate_simple_test(char *put_str)
718 {
719 char *chk_str;
720
721 if (ts.tst[ts.idx].put_handler)
722 return ts.tst[ts.idx].put_handler(put_str,
723 ts.tst[ts.idx].put);
724
725 chk_str = ts.tst[ts.idx].put;
726 if (*put_str == '$')
727 put_str++;
728
729 while (*chk_str != '\0' && *put_str != '\0') {
730 /* If someone does a * to match the rest of the string, allow
731 * it, or stop if the received string is complete.
732 */
733 if (*put_str == '#' || *chk_str == '*')
734 return 0;
735 if (*put_str != *chk_str)
736 return 1;
737
738 chk_str++;
739 put_str++;
740 }
741 if (*chk_str == '\0' && (*put_str == '\0' || *put_str == '#'))
742 return 0;
743
744 return 1;
745 }
746
run_simple_test(int is_get_char,int chr)747 static int run_simple_test(int is_get_char, int chr)
748 {
749 int ret = 0;
750 if (is_get_char) {
751 /* Send an ACK on the get if a prior put completed and set the
752 * send ack variable
753 */
754 if (send_ack) {
755 send_ack = 0;
756 return '+';
757 }
758 /* On the first get char, fill the transmit buffer and then
759 * take from the get_string.
760 */
761 if (get_buf_cnt == 0) {
762 if (ts.tst[ts.idx].get_handler)
763 ts.tst[ts.idx].get_handler(ts.tst[ts.idx].get);
764 else
765 fill_get_buf(ts.tst[ts.idx].get);
766 }
767
768 if (get_buf[get_buf_cnt] == '\0') {
769 eprintk("kgdbts: ERROR GET: EOB on '%s' at %i\n",
770 ts.name, ts.idx);
771 get_buf_cnt = 0;
772 fill_get_buf("D");
773 }
774 ret = get_buf[get_buf_cnt];
775 get_buf_cnt++;
776 return ret;
777 }
778
779 /* This callback is a put char which is when kgdb sends data to
780 * this I/O module.
781 */
782 if (ts.tst[ts.idx].get[0] == '\0' && ts.tst[ts.idx].put[0] == '\0' &&
783 !ts.tst[ts.idx].get_handler) {
784 eprintk("kgdbts: ERROR: beyond end of test on"
785 " '%s' line %i\n", ts.name, ts.idx);
786 return 0;
787 }
788
789 if (put_buf_cnt >= BUFMAX) {
790 eprintk("kgdbts: ERROR: put buffer overflow on"
791 " '%s' line %i\n", ts.name, ts.idx);
792 put_buf_cnt = 0;
793 return 0;
794 }
795 /* Ignore everything until the first valid packet start '$' */
796 if (put_buf_cnt == 0 && chr != '$')
797 return 0;
798
799 put_buf[put_buf_cnt] = chr;
800 put_buf_cnt++;
801
802 /* End of packet == #XX so look for the '#' */
803 if (put_buf_cnt > 3 && put_buf[put_buf_cnt - 3] == '#') {
804 if (put_buf_cnt >= BUFMAX) {
805 eprintk("kgdbts: ERROR: put buffer overflow on"
806 " '%s' line %i\n", ts.name, ts.idx);
807 put_buf_cnt = 0;
808 return 0;
809 }
810 put_buf[put_buf_cnt] = '\0';
811 v2printk("put%i: %s\n", ts.idx, put_buf);
812 /* Trigger check here */
813 if (ts.validate_put && ts.validate_put(put_buf)) {
814 eprintk("kgdbts: ERROR PUT: end of test "
815 "buffer on '%s' line %i expected %s got %s\n",
816 ts.name, ts.idx, ts.tst[ts.idx].put, put_buf);
817 }
818 ts.idx++;
819 put_buf_cnt = 0;
820 get_buf_cnt = 0;
821 send_ack = 1;
822 }
823 return 0;
824 }
825
init_simple_test(void)826 static void init_simple_test(void)
827 {
828 memset(&ts, 0, sizeof(ts));
829 ts.run_test = run_simple_test;
830 ts.validate_put = validate_simple_test;
831 }
832
run_plant_and_detach_test(int is_early)833 static void run_plant_and_detach_test(int is_early)
834 {
835 char before[BREAK_INSTR_SIZE];
836 char after[BREAK_INSTR_SIZE];
837
838 probe_kernel_read(before, (char *)kgdbts_break_test,
839 BREAK_INSTR_SIZE);
840 init_simple_test();
841 ts.tst = plant_and_detach_test;
842 ts.name = "plant_and_detach_test";
843 /* Activate test with initial breakpoint */
844 if (!is_early)
845 kgdb_breakpoint();
846 probe_kernel_read(after, (char *)kgdbts_break_test,
847 BREAK_INSTR_SIZE);
848 if (memcmp(before, after, BREAK_INSTR_SIZE)) {
849 printk(KERN_CRIT "kgdbts: ERROR kgdb corrupted memory\n");
850 panic("kgdb memory corruption");
851 }
852
853 /* complete the detach test */
854 if (!is_early)
855 kgdbts_break_test();
856 }
857
run_breakpoint_test(int is_hw_breakpoint)858 static void run_breakpoint_test(int is_hw_breakpoint)
859 {
860 test_complete = 0;
861 init_simple_test();
862 if (is_hw_breakpoint) {
863 ts.tst = hw_breakpoint_test;
864 ts.name = "hw_breakpoint_test";
865 } else {
866 ts.tst = sw_breakpoint_test;
867 ts.name = "sw_breakpoint_test";
868 }
869 /* Activate test with initial breakpoint */
870 kgdb_breakpoint();
871 /* run code with the break point in it */
872 kgdbts_break_test();
873 kgdb_breakpoint();
874
875 if (test_complete)
876 return;
877
878 eprintk("kgdbts: ERROR %s test failed\n", ts.name);
879 if (is_hw_breakpoint)
880 hwbreaks_ok = 0;
881 }
882
run_hw_break_test(int is_write_test)883 static void run_hw_break_test(int is_write_test)
884 {
885 test_complete = 0;
886 init_simple_test();
887 if (is_write_test) {
888 ts.tst = hw_write_break_test;
889 ts.name = "hw_write_break_test";
890 } else {
891 ts.tst = hw_access_break_test;
892 ts.name = "hw_access_break_test";
893 }
894 /* Activate test with initial breakpoint */
895 kgdb_breakpoint();
896 hw_break_val_access();
897 if (is_write_test) {
898 if (test_complete == 2) {
899 eprintk("kgdbts: ERROR %s broke on access\n",
900 ts.name);
901 hwbreaks_ok = 0;
902 }
903 hw_break_val_write();
904 }
905 kgdb_breakpoint();
906
907 if (test_complete == 1)
908 return;
909
910 eprintk("kgdbts: ERROR %s test failed\n", ts.name);
911 hwbreaks_ok = 0;
912 }
913
run_nmi_sleep_test(int nmi_sleep)914 static void run_nmi_sleep_test(int nmi_sleep)
915 {
916 unsigned long flags;
917
918 init_simple_test();
919 ts.tst = nmi_sleep_test;
920 ts.name = "nmi_sleep_test";
921 /* Activate test with initial breakpoint */
922 kgdb_breakpoint();
923 local_irq_save(flags);
924 mdelay(nmi_sleep*1000);
925 touch_nmi_watchdog();
926 local_irq_restore(flags);
927 if (test_complete != 2)
928 eprintk("kgdbts: ERROR nmi_test did not hit nmi\n");
929 kgdb_breakpoint();
930 if (test_complete == 1)
931 return;
932
933 eprintk("kgdbts: ERROR %s test failed\n", ts.name);
934 }
935
run_bad_read_test(void)936 static void run_bad_read_test(void)
937 {
938 init_simple_test();
939 ts.tst = bad_read_test;
940 ts.name = "bad_read_test";
941 /* Activate test with initial breakpoint */
942 kgdb_breakpoint();
943 }
944
run_do_fork_test(void)945 static void run_do_fork_test(void)
946 {
947 init_simple_test();
948 ts.tst = do_fork_test;
949 ts.name = "do_fork_test";
950 /* Activate test with initial breakpoint */
951 kgdb_breakpoint();
952 }
953
run_sys_open_test(void)954 static void run_sys_open_test(void)
955 {
956 init_simple_test();
957 ts.tst = sys_open_test;
958 ts.name = "sys_open_test";
959 /* Activate test with initial breakpoint */
960 kgdb_breakpoint();
961 }
962
run_singlestep_break_test(void)963 static void run_singlestep_break_test(void)
964 {
965 init_simple_test();
966 ts.tst = singlestep_break_test;
967 ts.name = "singlestep_breakpoint_test";
968 /* Activate test with initial breakpoint */
969 kgdb_breakpoint();
970 kgdbts_break_test();
971 kgdbts_break_test();
972 }
973
kgdbts_run_tests(void)974 static void kgdbts_run_tests(void)
975 {
976 char *ptr;
977 int fork_test = 0;
978 int do_sys_open_test = 0;
979 int sstep_test = 1000;
980 int nmi_sleep = 0;
981 int i;
982
983 verbose = 0;
984 if (strstr(config, "V1"))
985 verbose = 1;
986 if (strstr(config, "V2"))
987 verbose = 2;
988
989 ptr = strchr(config, 'F');
990 if (ptr)
991 fork_test = simple_strtol(ptr + 1, NULL, 10);
992 ptr = strchr(config, 'S');
993 if (ptr)
994 do_sys_open_test = simple_strtol(ptr + 1, NULL, 10);
995 ptr = strchr(config, 'N');
996 if (ptr)
997 nmi_sleep = simple_strtol(ptr+1, NULL, 10);
998 ptr = strchr(config, 'I');
999 if (ptr)
1000 sstep_test = simple_strtol(ptr+1, NULL, 10);
1001
1002 /* All HW break point tests */
1003 if (arch_kgdb_ops.flags & KGDB_HW_BREAKPOINT) {
1004 hwbreaks_ok = 1;
1005 v1printk("kgdbts:RUN hw breakpoint test\n");
1006 run_breakpoint_test(1);
1007 v1printk("kgdbts:RUN hw write breakpoint test\n");
1008 run_hw_break_test(1);
1009 v1printk("kgdbts:RUN access write breakpoint test\n");
1010 run_hw_break_test(0);
1011 }
1012
1013 /* required internal KGDB tests */
1014 v1printk("kgdbts:RUN plant and detach test\n");
1015 run_plant_and_detach_test(0);
1016 v1printk("kgdbts:RUN sw breakpoint test\n");
1017 run_breakpoint_test(0);
1018 v1printk("kgdbts:RUN bad memory access test\n");
1019 run_bad_read_test();
1020 v1printk("kgdbts:RUN singlestep test %i iterations\n", sstep_test);
1021 for (i = 0; i < sstep_test; i++) {
1022 run_singlestep_break_test();
1023 if (i % 100 == 0)
1024 v1printk("kgdbts:RUN singlestep [%i/%i]\n",
1025 i, sstep_test);
1026 }
1027
1028 /* ===Optional tests=== */
1029
1030 if (nmi_sleep) {
1031 v1printk("kgdbts:RUN NMI sleep %i seconds test\n", nmi_sleep);
1032 run_nmi_sleep_test(nmi_sleep);
1033 }
1034
1035 /* If the do_fork test is run it will be the last test that is
1036 * executed because a kernel thread will be spawned at the very
1037 * end to unregister the debug hooks.
1038 */
1039 if (fork_test) {
1040 repeat_test = fork_test;
1041 printk(KERN_INFO "kgdbts:RUN do_fork for %i breakpoints\n",
1042 repeat_test);
1043 kthread_run(kgdbts_unreg_thread, NULL, "kgdbts_unreg");
1044 run_do_fork_test();
1045 return;
1046 }
1047
1048 /* If the sys_open test is run it will be the last test that is
1049 * executed because a kernel thread will be spawned at the very
1050 * end to unregister the debug hooks.
1051 */
1052 if (do_sys_open_test) {
1053 repeat_test = do_sys_open_test;
1054 printk(KERN_INFO "kgdbts:RUN sys_open for %i breakpoints\n",
1055 repeat_test);
1056 kthread_run(kgdbts_unreg_thread, NULL, "kgdbts_unreg");
1057 run_sys_open_test();
1058 return;
1059 }
1060 /* Shutdown and unregister */
1061 kgdb_unregister_io_module(&kgdbts_io_ops);
1062 configured = 0;
1063 }
1064
kgdbts_option_setup(char * opt)1065 static int kgdbts_option_setup(char *opt)
1066 {
1067 if (strlen(opt) >= MAX_CONFIG_LEN) {
1068 printk(KERN_ERR "kgdbts: config string too long\n");
1069 return -ENOSPC;
1070 }
1071 strcpy(config, opt);
1072 return 0;
1073 }
1074
1075 __setup("kgdbts=", kgdbts_option_setup);
1076
configure_kgdbts(void)1077 static int configure_kgdbts(void)
1078 {
1079 int err = 0;
1080
1081 if (!strlen(config) || isspace(config[0]))
1082 goto noconfig;
1083
1084 final_ack = 0;
1085 run_plant_and_detach_test(1);
1086
1087 err = kgdb_register_io_module(&kgdbts_io_ops);
1088 if (err) {
1089 configured = 0;
1090 return err;
1091 }
1092 configured = 1;
1093 kgdbts_run_tests();
1094
1095 return err;
1096
1097 noconfig:
1098 config[0] = 0;
1099 configured = 0;
1100
1101 return err;
1102 }
1103
init_kgdbts(void)1104 static int __init init_kgdbts(void)
1105 {
1106 /* Already configured? */
1107 if (configured == 1)
1108 return 0;
1109
1110 return configure_kgdbts();
1111 }
1112 device_initcall(init_kgdbts);
1113
kgdbts_get_char(void)1114 static int kgdbts_get_char(void)
1115 {
1116 int val = 0;
1117
1118 if (ts.run_test)
1119 val = ts.run_test(1, 0);
1120
1121 return val;
1122 }
1123
kgdbts_put_char(u8 chr)1124 static void kgdbts_put_char(u8 chr)
1125 {
1126 if (ts.run_test)
1127 ts.run_test(0, chr);
1128 }
1129
param_set_kgdbts_var(const char * kmessage,struct kernel_param * kp)1130 static int param_set_kgdbts_var(const char *kmessage, struct kernel_param *kp)
1131 {
1132 size_t len = strlen(kmessage);
1133
1134 if (len >= MAX_CONFIG_LEN) {
1135 printk(KERN_ERR "kgdbts: config string too long\n");
1136 return -ENOSPC;
1137 }
1138
1139 /* Only copy in the string if the init function has not run yet */
1140 if (configured < 0) {
1141 strcpy(config, kmessage);
1142 return 0;
1143 }
1144
1145 if (configured == 1) {
1146 printk(KERN_ERR "kgdbts: ERROR: Already configured and running.\n");
1147 return -EBUSY;
1148 }
1149
1150 strcpy(config, kmessage);
1151 /* Chop out \n char as a result of echo */
1152 if (len && config[len - 1] == '\n')
1153 config[len - 1] = '\0';
1154
1155 /* Go and configure with the new params. */
1156 return configure_kgdbts();
1157 }
1158
kgdbts_pre_exp_handler(void)1159 static void kgdbts_pre_exp_handler(void)
1160 {
1161 /* Increment the module count when the debugger is active */
1162 if (!kgdb_connected)
1163 try_module_get(THIS_MODULE);
1164 }
1165
kgdbts_post_exp_handler(void)1166 static void kgdbts_post_exp_handler(void)
1167 {
1168 /* decrement the module count when the debugger detaches */
1169 if (!kgdb_connected)
1170 module_put(THIS_MODULE);
1171 }
1172
1173 static struct kgdb_io kgdbts_io_ops = {
1174 .name = "kgdbts",
1175 .read_char = kgdbts_get_char,
1176 .write_char = kgdbts_put_char,
1177 .pre_exception = kgdbts_pre_exp_handler,
1178 .post_exception = kgdbts_post_exp_handler,
1179 };
1180
1181 /*
1182 * not really modular, but the easiest way to keep compat with existing
1183 * bootargs behaviour is to continue using module_param here.
1184 */
1185 module_param_call(kgdbts, param_set_kgdbts_var, param_get_string, &kps, 0644);
1186 MODULE_PARM_DESC(kgdbts, "<A|V1|V2>[F#|S#][N#]");
1187