Root/drivers/misc/kgdbts.c

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
107#define v1printk(a...) do { \
108    if (verbose) \
109        printk(KERN_INFO a); \
110    } while (0)
111#define v2printk(a...) do { \
112    if (verbose > 1) \
113        printk(KERN_INFO a); \
114        touch_nmi_watchdog(); \
115    } while (0)
116#define eprintk(a...) do { \
117        printk(KERN_ERR a); \
118        WARN_ON(1); \
119    } while (0)
120#define MAX_CONFIG_LEN 40
121
122static struct kgdb_io kgdbts_io_ops;
123static char get_buf[BUFMAX];
124static int get_buf_cnt;
125static char put_buf[BUFMAX];
126static int put_buf_cnt;
127static char scratch_buf[BUFMAX];
128static int verbose;
129static int repeat_test;
130static int test_complete;
131static int send_ack;
132static int final_ack;
133static int force_hwbrks;
134static int hwbreaks_ok;
135static int hw_break_val;
136static int hw_break_val2;
137static int cont_instead_of_sstep;
138static unsigned long cont_thread_id;
139static unsigned long sstep_thread_id;
140#if defined(CONFIG_ARM) || defined(CONFIG_MIPS) || defined(CONFIG_SPARC)
141static int arch_needs_sstep_emulation = 1;
142#else
143static int arch_needs_sstep_emulation;
144#endif
145static unsigned long cont_addr;
146static unsigned long sstep_addr;
147static int restart_from_top_after_write;
148static int sstep_state;
149
150/* Storage for the registers, in GDB format. */
151static unsigned long kgdbts_gdb_regs[(NUMREGBYTES +
152                    sizeof(unsigned long) - 1) /
153                    sizeof(unsigned long)];
154static struct pt_regs kgdbts_regs;
155
156/* -1 = init not run yet, 0 = unconfigured, 1 = configured. */
157static int configured = -1;
158
159#ifdef CONFIG_KGDB_TESTS_BOOT_STRING
160static char config[MAX_CONFIG_LEN] = CONFIG_KGDB_TESTS_BOOT_STRING;
161#else
162static char config[MAX_CONFIG_LEN];
163#endif
164static struct kparam_string kps = {
165    .string = config,
166    .maxlen = MAX_CONFIG_LEN,
167};
168
169static void fill_get_buf(char *buf);
170
171struct test_struct {
172    char *get;
173    char *put;
174    void (*get_handler)(char *);
175    int (*put_handler)(char *, char *);
176};
177
178struct test_state {
179    char *name;
180    struct test_struct *tst;
181    int idx;
182    int (*run_test) (int, int);
183    int (*validate_put) (char *);
184};
185
186static struct test_state ts;
187
188static int kgdbts_unreg_thread(void *ptr)
189{
190    /* Wait until the tests are complete and then ungresiter the I/O
191     * driver.
192     */
193    while (!final_ack)
194        msleep_interruptible(1500);
195    /* Pause for any other threads to exit after final ack. */
196    msleep_interruptible(1000);
197    if (configured)
198        kgdb_unregister_io_module(&kgdbts_io_ops);
199    configured = 0;
200
201    return 0;
202}
203
204/* This is noinline such that it can be used for a single location to
205 * place a breakpoint
206 */
207static noinline void kgdbts_break_test(void)
208{
209    v2printk("kgdbts: breakpoint complete\n");
210}
211
212/* Lookup symbol info in the kernel */
213static unsigned long lookup_addr(char *arg)
214{
215    unsigned long addr = 0;
216
217    if (!strcmp(arg, "kgdbts_break_test"))
218        addr = (unsigned long)kgdbts_break_test;
219    else if (!strcmp(arg, "sys_open"))
220        addr = (unsigned long)do_sys_open;
221    else if (!strcmp(arg, "do_fork"))
222        addr = (unsigned long)do_fork;
223    else if (!strcmp(arg, "hw_break_val"))
224        addr = (unsigned long)&hw_break_val;
225    return addr;
226}
227
228static void break_helper(char *bp_type, char *arg, unsigned long vaddr)
229{
230    unsigned long addr;
231
232    if (arg)
233        addr = lookup_addr(arg);
234    else
235        addr = vaddr;
236
237    sprintf(scratch_buf, "%s,%lx,%i", bp_type, addr,
238        BREAK_INSTR_SIZE);
239    fill_get_buf(scratch_buf);
240}
241
242static void sw_break(char *arg)
243{
244    break_helper(force_hwbrks ? "Z1" : "Z0", arg, 0);
245}
246
247static void sw_rem_break(char *arg)
248{
249    break_helper(force_hwbrks ? "z1" : "z0", arg, 0);
250}
251
252static void hw_break(char *arg)
253{
254    break_helper("Z1", arg, 0);
255}
256
257static void hw_rem_break(char *arg)
258{
259    break_helper("z1", arg, 0);
260}
261
262static void hw_write_break(char *arg)
263{
264    break_helper("Z2", arg, 0);
265}
266
267static void hw_rem_write_break(char *arg)
268{
269    break_helper("z2", arg, 0);
270}
271
272static void hw_access_break(char *arg)
273{
274    break_helper("Z4", arg, 0);
275}
276
277static void hw_rem_access_break(char *arg)
278{
279    break_helper("z4", arg, 0);
280}
281
282static void hw_break_val_access(void)
283{
284    hw_break_val2 = hw_break_val;
285}
286
287static void hw_break_val_write(void)
288{
289    hw_break_val++;
290}
291
292static int get_thread_id_continue(char *put_str, char *arg)
293{
294    char *ptr = &put_str[11];
295
296    if (put_str[1] != 'T' || put_str[2] != '0')
297        return 1;
298    kgdb_hex2long(&ptr, &cont_thread_id);
299    return 0;
300}
301
302static int check_and_rewind_pc(char *put_str, char *arg)
303{
304    unsigned long addr = lookup_addr(arg);
305    unsigned long ip;
306    int offset = 0;
307
308    kgdb_hex2mem(&put_str[1], (char *)kgdbts_gdb_regs,
309         NUMREGBYTES);
310    gdb_regs_to_pt_regs(kgdbts_gdb_regs, &kgdbts_regs);
311    ip = instruction_pointer(&kgdbts_regs);
312    v2printk("Stopped at IP: %lx\n", ip);
313#ifdef GDB_ADJUSTS_BREAK_OFFSET
314    /* On some arches, a breakpoint stop requires it to be decremented */
315    if (addr + BREAK_INSTR_SIZE == ip)
316        offset = -BREAK_INSTR_SIZE;
317#endif
318
319    if (arch_needs_sstep_emulation && sstep_addr &&
320        ip + offset == sstep_addr &&
321        ((!strcmp(arg, "sys_open") || !strcmp(arg, "do_fork")))) {
322        /* This is special case for emulated single step */
323        v2printk("Emul: rewind hit single step bp\n");
324        restart_from_top_after_write = 1;
325    } else if (strcmp(arg, "silent") && ip + offset != addr) {
326        eprintk("kgdbts: BP mismatch %lx expected %lx\n",
327               ip + offset, addr);
328        return 1;
329    }
330    /* Readjust the instruction pointer if needed */
331    ip += offset;
332    cont_addr = ip;
333#ifdef GDB_ADJUSTS_BREAK_OFFSET
334    instruction_pointer_set(&kgdbts_regs, ip);
335#endif
336    return 0;
337}
338
339static int check_single_step(char *put_str, char *arg)
340{
341    unsigned long addr = lookup_addr(arg);
342    static int matched_id;
343
344    /*
345     * From an arch indepent point of view the instruction pointer
346     * should be on a different instruction
347     */
348    kgdb_hex2mem(&put_str[1], (char *)kgdbts_gdb_regs,
349         NUMREGBYTES);
350    gdb_regs_to_pt_regs(kgdbts_gdb_regs, &kgdbts_regs);
351    v2printk("Singlestep stopped at IP: %lx\n",
352           instruction_pointer(&kgdbts_regs));
353
354    if (sstep_thread_id != cont_thread_id) {
355        /*
356         * Ensure we stopped in the same thread id as before, else the
357         * debugger should continue until the original thread that was
358         * single stepped is scheduled again, emulating gdb's behavior.
359         */
360        v2printk("ThrID does not match: %lx\n", cont_thread_id);
361        if (arch_needs_sstep_emulation) {
362            if (matched_id &&
363                instruction_pointer(&kgdbts_regs) != addr)
364                goto continue_test;
365            matched_id++;
366            ts.idx -= 2;
367            sstep_state = 0;
368            return 0;
369        }
370        cont_instead_of_sstep = 1;
371        ts.idx -= 4;
372        return 0;
373    }
374continue_test:
375    matched_id = 0;
376    if (instruction_pointer(&kgdbts_regs) == addr) {
377        eprintk("kgdbts: SingleStep failed at %lx\n",
378               instruction_pointer(&kgdbts_regs));
379        return 1;
380    }
381
382    return 0;
383}
384
385static void write_regs(char *arg)
386{
387    memset(scratch_buf, 0, sizeof(scratch_buf));
388    scratch_buf[0] = 'G';
389    pt_regs_to_gdb_regs(kgdbts_gdb_regs, &kgdbts_regs);
390    kgdb_mem2hex((char *)kgdbts_gdb_regs, &scratch_buf[1], NUMREGBYTES);
391    fill_get_buf(scratch_buf);
392}
393
394static void skip_back_repeat_test(char *arg)
395{
396    int go_back = simple_strtol(arg, NULL, 10);
397
398    repeat_test--;
399    if (repeat_test <= 0)
400        ts.idx++;
401    else
402        ts.idx -= go_back;
403    fill_get_buf(ts.tst[ts.idx].get);
404}
405
406static int got_break(char *put_str, char *arg)
407{
408    test_complete = 1;
409    if (!strncmp(put_str+1, arg, 2)) {
410        if (!strncmp(arg, "T0", 2))
411            test_complete = 2;
412        return 0;
413    }
414    return 1;
415}
416
417static void get_cont_catch(char *arg)
418{
419    /* Always send detach because the test is completed at this point */
420    fill_get_buf("D");
421}
422
423static int put_cont_catch(char *put_str, char *arg)
424{
425    /* This is at the end of the test and we catch any and all input */
426    v2printk("kgdbts: cleanup task: %lx\n", sstep_thread_id);
427    ts.idx--;
428    return 0;
429}
430
431static int emul_reset(char *put_str, char *arg)
432{
433    if (strncmp(put_str, "$OK", 3))
434        return 1;
435    if (restart_from_top_after_write) {
436        restart_from_top_after_write = 0;
437        ts.idx = -1;
438    }
439    return 0;
440}
441
442static void emul_sstep_get(char *arg)
443{
444    if (!arch_needs_sstep_emulation) {
445        if (cont_instead_of_sstep) {
446            cont_instead_of_sstep = 0;
447            fill_get_buf("c");
448        } else {
449            fill_get_buf(arg);
450        }
451        return;
452    }
453    switch (sstep_state) {
454    case 0:
455        v2printk("Emulate single step\n");
456        /* Start by looking at the current PC */
457        fill_get_buf("g");
458        break;
459    case 1:
460        /* set breakpoint */
461        break_helper("Z0", NULL, sstep_addr);
462        break;
463    case 2:
464        /* Continue */
465        fill_get_buf("c");
466        break;
467    case 3:
468        /* Clear breakpoint */
469        break_helper("z0", NULL, sstep_addr);
470        break;
471    default:
472        eprintk("kgdbts: ERROR failed sstep get emulation\n");
473    }
474    sstep_state++;
475}
476
477static int emul_sstep_put(char *put_str, char *arg)
478{
479    if (!arch_needs_sstep_emulation) {
480        char *ptr = &put_str[11];
481        if (put_str[1] != 'T' || put_str[2] != '0')
482            return 1;
483        kgdb_hex2long(&ptr, &sstep_thread_id);
484        return 0;
485    }
486    switch (sstep_state) {
487    case 1:
488        /* validate the "g" packet to get the IP */
489        kgdb_hex2mem(&put_str[1], (char *)kgdbts_gdb_regs,
490             NUMREGBYTES);
491        gdb_regs_to_pt_regs(kgdbts_gdb_regs, &kgdbts_regs);
492        v2printk("Stopped at IP: %lx\n",
493             instruction_pointer(&kgdbts_regs));
494        /* Want to stop at IP + break instruction size by default */
495        sstep_addr = cont_addr + BREAK_INSTR_SIZE;
496        break;
497    case 2:
498        if (strncmp(put_str, "$OK", 3)) {
499            eprintk("kgdbts: failed sstep break set\n");
500            return 1;
501        }
502        break;
503    case 3:
504        if (strncmp(put_str, "$T0", 3)) {
505            eprintk("kgdbts: failed continue sstep\n");
506            return 1;
507        } else {
508            char *ptr = &put_str[11];
509            kgdb_hex2long(&ptr, &sstep_thread_id);
510        }
511        break;
512    case 4:
513        if (strncmp(put_str, "$OK", 3)) {
514            eprintk("kgdbts: failed sstep break unset\n");
515            return 1;
516        }
517        /* Single step is complete so continue on! */
518        sstep_state = 0;
519        return 0;
520    default:
521        eprintk("kgdbts: ERROR failed sstep put emulation\n");
522    }
523
524    /* Continue on the same test line until emulation is complete */
525    ts.idx--;
526    return 0;
527}
528
529static int final_ack_set(char *put_str, char *arg)
530{
531    if (strncmp(put_str+1, arg, 2))
532        return 1;
533    final_ack = 1;
534    return 0;
535}
536/*
537 * Test to plant a breakpoint and detach, which should clear out the
538 * breakpoint and restore the original instruction.
539 */
540static struct test_struct plant_and_detach_test[] = {
541    { "?", "S0*" }, /* Clear break points */
542    { "kgdbts_break_test", "OK", sw_break, }, /* set sw breakpoint */
543    { "D", "OK" }, /* Detach */
544    { "", "" },
545};
546
547/*
548 * Simple test to write in a software breakpoint, check for the
549 * correct stop location and detach.
550 */
551static struct test_struct sw_breakpoint_test[] = {
552    { "?", "S0*" }, /* Clear break points */
553    { "kgdbts_break_test", "OK", sw_break, }, /* set sw breakpoint */
554    { "c", "T0*", }, /* Continue */
555    { "g", "kgdbts_break_test", NULL, check_and_rewind_pc },
556    { "write", "OK", write_regs },
557    { "kgdbts_break_test", "OK", sw_rem_break }, /*remove breakpoint */
558    { "D", "OK" }, /* Detach */
559    { "D", "OK", NULL, got_break }, /* On success we made it here */
560    { "", "" },
561};
562
563/*
564 * Test a known bad memory read location to test the fault handler and
565 * read bytes 1-8 at the bad address
566 */
567static struct test_struct bad_read_test[] = {
568    { "?", "S0*" }, /* Clear break points */
569    { "m0,1", "E*" }, /* read 1 byte at address 1 */
570    { "m0,2", "E*" }, /* read 1 byte at address 2 */
571    { "m0,3", "E*" }, /* read 1 byte at address 3 */
572    { "m0,4", "E*" }, /* read 1 byte at address 4 */
573    { "m0,5", "E*" }, /* read 1 byte at address 5 */
574    { "m0,6", "E*" }, /* read 1 byte at address 6 */
575    { "m0,7", "E*" }, /* read 1 byte at address 7 */
576    { "m0,8", "E*" }, /* read 1 byte at address 8 */
577    { "D", "OK" }, /* Detach which removes all breakpoints and continues */
578    { "", "" },
579};
580
581/*
582 * Test for hitting a breakpoint, remove it, single step, plant it
583 * again and detach.
584 */
585static struct test_struct singlestep_break_test[] = {
586    { "?", "S0*" }, /* Clear break points */
587    { "kgdbts_break_test", "OK", sw_break, }, /* set sw breakpoint */
588    { "c", "T0*", NULL, get_thread_id_continue }, /* Continue */
589    { "kgdbts_break_test", "OK", sw_rem_break }, /*remove breakpoint */
590    { "g", "kgdbts_break_test", NULL, check_and_rewind_pc },
591    { "write", "OK", write_regs }, /* Write registers */
592    { "s", "T0*", emul_sstep_get, emul_sstep_put }, /* Single step */
593    { "g", "kgdbts_break_test", NULL, check_single_step },
594    { "kgdbts_break_test", "OK", sw_break, }, /* set sw breakpoint */
595    { "c", "T0*", }, /* Continue */
596    { "g", "kgdbts_break_test", NULL, check_and_rewind_pc },
597    { "write", "OK", write_regs }, /* Write registers */
598    { "D", "OK" }, /* Remove all breakpoints and continues */
599    { "", "" },
600};
601
602/*
603 * Test for hitting a breakpoint at do_fork for what ever the number
604 * of iterations required by the variable repeat_test.
605 */
606static struct test_struct do_fork_test[] = {
607    { "?", "S0*" }, /* Clear break points */
608    { "do_fork", "OK", sw_break, }, /* set sw breakpoint */
609    { "c", "T0*", NULL, get_thread_id_continue }, /* Continue */
610    { "do_fork", "OK", sw_rem_break }, /*remove breakpoint */
611    { "g", "do_fork", NULL, check_and_rewind_pc }, /* check location */
612    { "write", "OK", write_regs, emul_reset }, /* Write registers */
613    { "s", "T0*", emul_sstep_get, emul_sstep_put }, /* Single step */
614    { "g", "do_fork", NULL, check_single_step },
615    { "do_fork", "OK", sw_break, }, /* set sw breakpoint */
616    { "7", "T0*", skip_back_repeat_test }, /* Loop based on repeat_test */
617    { "D", "OK", NULL, final_ack_set }, /* detach and unregister I/O */
618    { "", "", get_cont_catch, put_cont_catch },
619};
620
621/* Test for hitting a breakpoint at sys_open for what ever the number
622 * of iterations required by the variable repeat_test.
623 */
624static struct test_struct sys_open_test[] = {
625    { "?", "S0*" }, /* Clear break points */
626    { "sys_open", "OK", sw_break, }, /* set sw breakpoint */
627    { "c", "T0*", NULL, get_thread_id_continue }, /* Continue */
628    { "sys_open", "OK", sw_rem_break }, /*remove breakpoint */
629    { "g", "sys_open", NULL, check_and_rewind_pc }, /* check location */
630    { "write", "OK", write_regs, emul_reset }, /* Write registers */
631    { "s", "T0*", emul_sstep_get, emul_sstep_put }, /* Single step */
632    { "g", "sys_open", NULL, check_single_step },
633    { "sys_open", "OK", sw_break, }, /* set sw breakpoint */
634    { "7", "T0*", skip_back_repeat_test }, /* Loop based on repeat_test */
635    { "D", "OK", NULL, final_ack_set }, /* detach and unregister I/O */
636    { "", "", get_cont_catch, put_cont_catch },
637};
638
639/*
640 * Test for hitting a simple hw breakpoint
641 */
642static struct test_struct hw_breakpoint_test[] = {
643    { "?", "S0*" }, /* Clear break points */
644    { "kgdbts_break_test", "OK", hw_break, }, /* set hw breakpoint */
645    { "c", "T0*", }, /* Continue */
646    { "g", "kgdbts_break_test", NULL, check_and_rewind_pc },
647    { "write", "OK", write_regs },
648    { "kgdbts_break_test", "OK", hw_rem_break }, /*remove breakpoint */
649    { "D", "OK" }, /* Detach */
650    { "D", "OK", NULL, got_break }, /* On success we made it here */
651    { "", "" },
652};
653
654/*
655 * Test for hitting a hw write breakpoint
656 */
657static struct test_struct hw_write_break_test[] = {
658    { "?", "S0*" }, /* Clear break points */
659    { "hw_break_val", "OK", hw_write_break, }, /* set hw breakpoint */
660    { "c", "T0*", NULL, got_break }, /* Continue */
661    { "g", "silent", NULL, check_and_rewind_pc },
662    { "write", "OK", write_regs },
663    { "hw_break_val", "OK", hw_rem_write_break }, /*remove breakpoint */
664    { "D", "OK" }, /* Detach */
665    { "D", "OK", NULL, got_break }, /* On success we made it here */
666    { "", "" },
667};
668
669/*
670 * Test for hitting a hw access breakpoint
671 */
672static struct test_struct hw_access_break_test[] = {
673    { "?", "S0*" }, /* Clear break points */
674    { "hw_break_val", "OK", hw_access_break, }, /* set hw breakpoint */
675    { "c", "T0*", NULL, got_break }, /* Continue */
676    { "g", "silent", NULL, check_and_rewind_pc },
677    { "write", "OK", write_regs },
678    { "hw_break_val", "OK", hw_rem_access_break }, /*remove breakpoint */
679    { "D", "OK" }, /* Detach */
680    { "D", "OK", NULL, got_break }, /* On success we made it here */
681    { "", "" },
682};
683
684/*
685 * Test for hitting a hw access breakpoint
686 */
687static struct test_struct nmi_sleep_test[] = {
688    { "?", "S0*" }, /* Clear break points */
689    { "c", "T0*", NULL, got_break }, /* Continue */
690    { "D", "OK" }, /* Detach */
691    { "D", "OK", NULL, got_break }, /* On success we made it here */
692    { "", "" },
693};
694
695static void fill_get_buf(char *buf)
696{
697    unsigned char checksum = 0;
698    int count = 0;
699    char ch;
700
701    strcpy(get_buf, "$");
702    strcat(get_buf, buf);
703    while ((ch = buf[count])) {
704        checksum += ch;
705        count++;
706    }
707    strcat(get_buf, "#");
708    get_buf[count + 2] = hex_asc_hi(checksum);
709    get_buf[count + 3] = hex_asc_lo(checksum);
710    get_buf[count + 4] = '\0';
711    v2printk("get%i: %s\n", ts.idx, get_buf);
712}
713
714static int validate_simple_test(char *put_str)
715{
716    char *chk_str;
717
718    if (ts.tst[ts.idx].put_handler)
719        return ts.tst[ts.idx].put_handler(put_str,
720            ts.tst[ts.idx].put);
721
722    chk_str = ts.tst[ts.idx].put;
723    if (*put_str == '$')
724        put_str++;
725
726    while (*chk_str != '\0' && *put_str != '\0') {
727        /* If someone does a * to match the rest of the string, allow
728         * it, or stop if the received string is complete.
729         */
730        if (*put_str == '#' || *chk_str == '*')
731            return 0;
732        if (*put_str != *chk_str)
733            return 1;
734
735        chk_str++;
736        put_str++;
737    }
738    if (*chk_str == '\0' && (*put_str == '\0' || *put_str == '#'))
739        return 0;
740
741    return 1;
742}
743
744static int run_simple_test(int is_get_char, int chr)
745{
746    int ret = 0;
747    if (is_get_char) {
748        /* Send an ACK on the get if a prior put completed and set the
749         * send ack variable
750         */
751        if (send_ack) {
752            send_ack = 0;
753            return '+';
754        }
755        /* On the first get char, fill the transmit buffer and then
756         * take from the get_string.
757         */
758        if (get_buf_cnt == 0) {
759            if (ts.tst[ts.idx].get_handler)
760                ts.tst[ts.idx].get_handler(ts.tst[ts.idx].get);
761            else
762                fill_get_buf(ts.tst[ts.idx].get);
763        }
764
765        if (get_buf[get_buf_cnt] == '\0') {
766            eprintk("kgdbts: ERROR GET: EOB on '%s' at %i\n",
767               ts.name, ts.idx);
768            get_buf_cnt = 0;
769            fill_get_buf("D");
770        }
771        ret = get_buf[get_buf_cnt];
772        get_buf_cnt++;
773        return ret;
774    }
775
776    /* This callback is a put char which is when kgdb sends data to
777     * this I/O module.
778     */
779    if (ts.tst[ts.idx].get[0] == '\0' && ts.tst[ts.idx].put[0] == '\0' &&
780        !ts.tst[ts.idx].get_handler) {
781        eprintk("kgdbts: ERROR: beyond end of test on"
782               " '%s' line %i\n", ts.name, ts.idx);
783        return 0;
784    }
785
786    if (put_buf_cnt >= BUFMAX) {
787        eprintk("kgdbts: ERROR: put buffer overflow on"
788               " '%s' line %i\n", ts.name, ts.idx);
789        put_buf_cnt = 0;
790        return 0;
791    }
792    /* Ignore everything until the first valid packet start '$' */
793    if (put_buf_cnt == 0 && chr != '$')
794        return 0;
795
796    put_buf[put_buf_cnt] = chr;
797    put_buf_cnt++;
798
799    /* End of packet == #XX so look for the '#' */
800    if (put_buf_cnt > 3 && put_buf[put_buf_cnt - 3] == '#') {
801        if (put_buf_cnt >= BUFMAX) {
802            eprintk("kgdbts: ERROR: put buffer overflow on"
803                " '%s' line %i\n", ts.name, ts.idx);
804            put_buf_cnt = 0;
805            return 0;
806        }
807        put_buf[put_buf_cnt] = '\0';
808        v2printk("put%i: %s\n", ts.idx, put_buf);
809        /* Trigger check here */
810        if (ts.validate_put && ts.validate_put(put_buf)) {
811            eprintk("kgdbts: ERROR PUT: end of test "
812               "buffer on '%s' line %i expected %s got %s\n",
813               ts.name, ts.idx, ts.tst[ts.idx].put, put_buf);
814        }
815        ts.idx++;
816        put_buf_cnt = 0;
817        get_buf_cnt = 0;
818        send_ack = 1;
819    }
820    return 0;
821}
822
823static void init_simple_test(void)
824{
825    memset(&ts, 0, sizeof(ts));
826    ts.run_test = run_simple_test;
827    ts.validate_put = validate_simple_test;
828}
829
830static void run_plant_and_detach_test(int is_early)
831{
832    char before[BREAK_INSTR_SIZE];
833    char after[BREAK_INSTR_SIZE];
834
835    probe_kernel_read(before, (char *)kgdbts_break_test,
836      BREAK_INSTR_SIZE);
837    init_simple_test();
838    ts.tst = plant_and_detach_test;
839    ts.name = "plant_and_detach_test";
840    /* Activate test with initial breakpoint */
841    if (!is_early)
842        kgdb_breakpoint();
843    probe_kernel_read(after, (char *)kgdbts_break_test,
844      BREAK_INSTR_SIZE);
845    if (memcmp(before, after, BREAK_INSTR_SIZE)) {
846        printk(KERN_CRIT "kgdbts: ERROR kgdb corrupted memory\n");
847        panic("kgdb memory corruption");
848    }
849
850    /* complete the detach test */
851    if (!is_early)
852        kgdbts_break_test();
853}
854
855static void run_breakpoint_test(int is_hw_breakpoint)
856{
857    test_complete = 0;
858    init_simple_test();
859    if (is_hw_breakpoint) {
860        ts.tst = hw_breakpoint_test;
861        ts.name = "hw_breakpoint_test";
862    } else {
863        ts.tst = sw_breakpoint_test;
864        ts.name = "sw_breakpoint_test";
865    }
866    /* Activate test with initial breakpoint */
867    kgdb_breakpoint();
868    /* run code with the break point in it */
869    kgdbts_break_test();
870    kgdb_breakpoint();
871
872    if (test_complete)
873        return;
874
875    eprintk("kgdbts: ERROR %s test failed\n", ts.name);
876    if (is_hw_breakpoint)
877        hwbreaks_ok = 0;
878}
879
880static void run_hw_break_test(int is_write_test)
881{
882    test_complete = 0;
883    init_simple_test();
884    if (is_write_test) {
885        ts.tst = hw_write_break_test;
886        ts.name = "hw_write_break_test";
887    } else {
888        ts.tst = hw_access_break_test;
889        ts.name = "hw_access_break_test";
890    }
891    /* Activate test with initial breakpoint */
892    kgdb_breakpoint();
893    hw_break_val_access();
894    if (is_write_test) {
895        if (test_complete == 2) {
896            eprintk("kgdbts: ERROR %s broke on access\n",
897                ts.name);
898            hwbreaks_ok = 0;
899        }
900        hw_break_val_write();
901    }
902    kgdb_breakpoint();
903
904    if (test_complete == 1)
905        return;
906
907    eprintk("kgdbts: ERROR %s test failed\n", ts.name);
908    hwbreaks_ok = 0;
909}
910
911static void run_nmi_sleep_test(int nmi_sleep)
912{
913    unsigned long flags;
914
915    init_simple_test();
916    ts.tst = nmi_sleep_test;
917    ts.name = "nmi_sleep_test";
918    /* Activate test with initial breakpoint */
919    kgdb_breakpoint();
920    local_irq_save(flags);
921    mdelay(nmi_sleep*1000);
922    touch_nmi_watchdog();
923    local_irq_restore(flags);
924    if (test_complete != 2)
925        eprintk("kgdbts: ERROR nmi_test did not hit nmi\n");
926    kgdb_breakpoint();
927    if (test_complete == 1)
928        return;
929
930    eprintk("kgdbts: ERROR %s test failed\n", ts.name);
931}
932
933static void run_bad_read_test(void)
934{
935    init_simple_test();
936    ts.tst = bad_read_test;
937    ts.name = "bad_read_test";
938    /* Activate test with initial breakpoint */
939    kgdb_breakpoint();
940}
941
942static void run_do_fork_test(void)
943{
944    init_simple_test();
945    ts.tst = do_fork_test;
946    ts.name = "do_fork_test";
947    /* Activate test with initial breakpoint */
948    kgdb_breakpoint();
949}
950
951static void run_sys_open_test(void)
952{
953    init_simple_test();
954    ts.tst = sys_open_test;
955    ts.name = "sys_open_test";
956    /* Activate test with initial breakpoint */
957    kgdb_breakpoint();
958}
959
960static void run_singlestep_break_test(void)
961{
962    init_simple_test();
963    ts.tst = singlestep_break_test;
964    ts.name = "singlestep_breakpoint_test";
965    /* Activate test with initial breakpoint */
966    kgdb_breakpoint();
967    kgdbts_break_test();
968    kgdbts_break_test();
969}
970
971static void kgdbts_run_tests(void)
972{
973    char *ptr;
974    int fork_test = 0;
975    int do_sys_open_test = 0;
976    int sstep_test = 1000;
977    int nmi_sleep = 0;
978    int i;
979
980    ptr = strchr(config, 'F');
981    if (ptr)
982        fork_test = simple_strtol(ptr + 1, NULL, 10);
983    ptr = strchr(config, 'S');
984    if (ptr)
985        do_sys_open_test = simple_strtol(ptr + 1, NULL, 10);
986    ptr = strchr(config, 'N');
987    if (ptr)
988        nmi_sleep = simple_strtol(ptr+1, NULL, 10);
989    ptr = strchr(config, 'I');
990    if (ptr)
991        sstep_test = simple_strtol(ptr+1, NULL, 10);
992
993    /* All HW break point tests */
994    if (arch_kgdb_ops.flags & KGDB_HW_BREAKPOINT) {
995        hwbreaks_ok = 1;
996        v1printk("kgdbts:RUN hw breakpoint test\n");
997        run_breakpoint_test(1);
998        v1printk("kgdbts:RUN hw write breakpoint test\n");
999        run_hw_break_test(1);
1000        v1printk("kgdbts:RUN access write breakpoint test\n");
1001        run_hw_break_test(0);
1002    }
1003
1004    /* required internal KGDB tests */
1005    v1printk("kgdbts:RUN plant and detach test\n");
1006    run_plant_and_detach_test(0);
1007    v1printk("kgdbts:RUN sw breakpoint test\n");
1008    run_breakpoint_test(0);
1009    v1printk("kgdbts:RUN bad memory access test\n");
1010    run_bad_read_test();
1011    v1printk("kgdbts:RUN singlestep test %i iterations\n", sstep_test);
1012    for (i = 0; i < sstep_test; i++) {
1013        run_singlestep_break_test();
1014        if (i % 100 == 0)
1015            v1printk("kgdbts:RUN singlestep [%i/%i]\n",
1016                 i, sstep_test);
1017    }
1018
1019    /* ===Optional tests=== */
1020
1021    if (nmi_sleep) {
1022        v1printk("kgdbts:RUN NMI sleep %i seconds test\n", nmi_sleep);
1023        run_nmi_sleep_test(nmi_sleep);
1024    }
1025
1026    /* If the do_fork test is run it will be the last test that is
1027     * executed because a kernel thread will be spawned at the very
1028     * end to unregister the debug hooks.
1029     */
1030    if (fork_test) {
1031        repeat_test = fork_test;
1032        printk(KERN_INFO "kgdbts:RUN do_fork for %i breakpoints\n",
1033            repeat_test);
1034        kthread_run(kgdbts_unreg_thread, NULL, "kgdbts_unreg");
1035        run_do_fork_test();
1036        return;
1037    }
1038
1039    /* If the sys_open test is run it will be the last test that is
1040     * executed because a kernel thread will be spawned at the very
1041     * end to unregister the debug hooks.
1042     */
1043    if (do_sys_open_test) {
1044        repeat_test = do_sys_open_test;
1045        printk(KERN_INFO "kgdbts:RUN sys_open for %i breakpoints\n",
1046            repeat_test);
1047        kthread_run(kgdbts_unreg_thread, NULL, "kgdbts_unreg");
1048        run_sys_open_test();
1049        return;
1050    }
1051    /* Shutdown and unregister */
1052    kgdb_unregister_io_module(&kgdbts_io_ops);
1053    configured = 0;
1054}
1055
1056static int kgdbts_option_setup(char *opt)
1057{
1058    if (strlen(opt) >= MAX_CONFIG_LEN) {
1059        printk(KERN_ERR "kgdbts: config string too long\n");
1060        return -ENOSPC;
1061    }
1062    strcpy(config, opt);
1063
1064    verbose = 0;
1065    if (strstr(config, "V1"))
1066        verbose = 1;
1067    if (strstr(config, "V2"))
1068        verbose = 2;
1069
1070    return 0;
1071}
1072
1073__setup("kgdbts=", kgdbts_option_setup);
1074
1075static int configure_kgdbts(void)
1076{
1077    int err = 0;
1078
1079    if (!strlen(config) || isspace(config[0]))
1080        goto noconfig;
1081    err = kgdbts_option_setup(config);
1082    if (err)
1083        goto noconfig;
1084
1085    final_ack = 0;
1086    run_plant_and_detach_test(1);
1087
1088    err = kgdb_register_io_module(&kgdbts_io_ops);
1089    if (err) {
1090        configured = 0;
1091        return err;
1092    }
1093    configured = 1;
1094    kgdbts_run_tests();
1095
1096    return err;
1097
1098noconfig:
1099    config[0] = 0;
1100    configured = 0;
1101
1102    return err;
1103}
1104
1105static int __init init_kgdbts(void)
1106{
1107    /* Already configured? */
1108    if (configured == 1)
1109        return 0;
1110
1111    return configure_kgdbts();
1112}
1113
1114static 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
1124static void kgdbts_put_char(u8 chr)
1125{
1126    if (ts.run_test)
1127        ts.run_test(0, chr);
1128}
1129
1130static int param_set_kgdbts_var(const char *kmessage, struct kernel_param *kp)
1131{
1132    int 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 (config[len - 1] == '\n')
1153        config[len - 1] = '\0';
1154
1155    /* Go and configure with the new params. */
1156    return configure_kgdbts();
1157}
1158
1159static 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
1166static 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
1173static 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
1181module_init(init_kgdbts);
1182module_param_call(kgdbts, param_set_kgdbts_var, param_get_string, &kps, 0644);
1183MODULE_PARM_DESC(kgdbts, "<A|V1|V2>[F#|S#][N#]");
1184MODULE_DESCRIPTION("KGDB Test Suite");
1185MODULE_LICENSE("GPL");
1186MODULE_AUTHOR("Wind River Systems, Inc.");
1187
1188

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