The Design and Implementation of the FreeBSD Operating System, Second Edition
Now available: The Design and Implementation of the FreeBSD Operating System (Second Edition)


[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]

FreeBSD/Linux Kernel Cross Reference
sys/gdb/gdb_main.c

Version: -  FREEBSD  -  FREEBSD-13-STABLE  -  FREEBSD-13-0  -  FREEBSD-12-STABLE  -  FREEBSD-12-0  -  FREEBSD-11-STABLE  -  FREEBSD-11-0  -  FREEBSD-10-STABLE  -  FREEBSD-10-0  -  FREEBSD-9-STABLE  -  FREEBSD-9-0  -  FREEBSD-8-STABLE  -  FREEBSD-8-0  -  FREEBSD-7-STABLE  -  FREEBSD-7-0  -  FREEBSD-6-STABLE  -  FREEBSD-6-0  -  FREEBSD-5-STABLE  -  FREEBSD-5-0  -  FREEBSD-4-STABLE  -  FREEBSD-3-STABLE  -  FREEBSD22  -  l41  -  OPENBSD  -  linux-2.6  -  MK84  -  PLAN9  -  xnu-8792 
SearchContext: -  none  -  3  -  10 

    1 /*-
    2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
    3  *
    4  * Copyright (c) 2004 Marcel Moolenaar
    5  * All rights reserved.
    6  *
    7  * Redistribution and use in source and binary forms, with or without
    8  * modification, are permitted provided that the following conditions
    9  * are met:
   10  *
   11  * 1. Redistributions of source code must retain the above copyright
   12  *    notice, this list of conditions and the following disclaimer.
   13  * 2. Redistributions in binary form must reproduce the above copyright
   14  *    notice, this list of conditions and the following disclaimer in the
   15  *    documentation and/or other materials provided with the distribution.
   16  *
   17  * THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS OR
   18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
   19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
   20  * IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY DIRECT, INDIRECT,
   21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
   22  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
   23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
   24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
   25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
   26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
   27  */
   28 
   29 #include <sys/cdefs.h>
   30 __FBSDID("$FreeBSD: releng/12.0/sys/gdb/gdb_main.c 326269 2017-11-27 15:16:59Z pfg $");
   31 
   32 #include <sys/param.h>
   33 #include <sys/systm.h>
   34 #include <sys/kdb.h>
   35 #include <sys/kernel.h>
   36 #include <sys/pcpu.h>
   37 #include <sys/proc.h>
   38 #include <sys/reboot.h>
   39 
   40 #include <machine/gdb_machdep.h>
   41 #include <machine/kdb.h>
   42 
   43 #include <gdb/gdb.h>
   44 #include <gdb/gdb_int.h>
   45 
   46 static dbbe_init_f gdb_init;
   47 static dbbe_trap_f gdb_trap;
   48 
   49 KDB_BACKEND(gdb, gdb_init, NULL, NULL, gdb_trap);
   50 
   51 static struct gdb_dbgport null_gdb_dbgport;
   52 DATA_SET(gdb_dbgport_set, null_gdb_dbgport);
   53 SET_DECLARE(gdb_dbgport_set, struct gdb_dbgport);
   54 
   55 struct gdb_dbgport *gdb_cur = NULL;
   56 int gdb_listening = 0;
   57 
   58 static unsigned char gdb_bindata[64];
   59 
   60 static int
   61 gdb_init(void)
   62 {
   63         struct gdb_dbgport *dp, **iter;
   64         int cur_pri, pri;
   65 
   66         gdb_cur = NULL;
   67         cur_pri = -1;
   68         SET_FOREACH(iter, gdb_dbgport_set) {
   69                 dp = *iter;
   70                 pri = (dp->gdb_probe != NULL) ? dp->gdb_probe() : -1;
   71                 dp->gdb_active = (pri >= 0) ? 0 : -1;
   72                 if (pri > cur_pri) {
   73                         cur_pri = pri;
   74                         gdb_cur = dp;
   75                 }
   76         }
   77         if (gdb_cur != NULL) {
   78                 printf("GDB: debug ports:");
   79                 SET_FOREACH(iter, gdb_dbgport_set) {
   80                         dp = *iter;
   81                         if (dp->gdb_active == 0)
   82                                 printf(" %s", dp->gdb_name);
   83                 }
   84                 printf("\n");
   85         } else
   86                 printf("GDB: no debug ports present\n");
   87         if (gdb_cur != NULL) {
   88                 gdb_cur->gdb_init();
   89                 printf("GDB: current port: %s\n", gdb_cur->gdb_name);
   90         }
   91         if (gdb_cur != NULL) {
   92                 cur_pri = (boothowto & RB_GDB) ? 2 : 0;
   93                 gdb_consinit();
   94         } else
   95                 cur_pri = -1;
   96         return (cur_pri);
   97 }
   98 
   99 static void
  100 gdb_do_mem_search(void)
  101 {
  102         size_t patlen;
  103         intmax_t addr, size;
  104         const unsigned char *found;
  105 
  106         if (gdb_rx_varhex(&addr) || gdb_rx_char() != ';' ||
  107             gdb_rx_varhex(&size) || gdb_rx_char() != ';' ||
  108             gdb_rx_bindata(gdb_bindata, sizeof(gdb_bindata), &patlen)) {
  109                 gdb_tx_err(EINVAL);
  110                 return;
  111         }
  112         if (gdb_search_mem((char *)(uintptr_t)addr, size, gdb_bindata,
  113             patlen, &found)) {
  114                 if (found == 0ULL)
  115                         gdb_tx_begin('');
  116                 else {
  117                         gdb_tx_begin('1');
  118                         gdb_tx_char(',');
  119                         gdb_tx_hex((intmax_t)(uintptr_t)found, 8);
  120                 }
  121                 gdb_tx_end();
  122         } else
  123                 gdb_tx_err(EIO);
  124 }
  125 
  126 static int
  127 gdb_trap(int type, int code)
  128 {
  129         jmp_buf jb;
  130         struct thread *thr_iter;
  131         void *prev_jb;
  132 
  133         prev_jb = kdb_jmpbuf(jb);
  134         if (setjmp(jb) != 0) {
  135                 printf("%s bailing, hopefully back to ddb!\n", __func__);
  136                 gdb_listening = 0;
  137                 (void)kdb_jmpbuf(prev_jb);
  138                 return (1);
  139         }
  140 
  141         gdb_listening = 0;
  142         /*
  143          * Send a T packet. We currently do not support watchpoints (the
  144          * awatch, rwatch or watch elements).
  145          */
  146         gdb_tx_begin('T');
  147         gdb_tx_hex(gdb_cpu_signal(type, code), 2);
  148         gdb_tx_varhex(GDB_REG_PC);
  149         gdb_tx_char(':');
  150         gdb_tx_reg(GDB_REG_PC);
  151         gdb_tx_char(';');
  152         gdb_tx_str("thread:");
  153         gdb_tx_varhex((long)kdb_thread->td_tid);
  154         gdb_tx_char(';');
  155         gdb_tx_end();                   /* XXX check error condition. */
  156 
  157         thr_iter = NULL;
  158         while (gdb_rx_begin() == 0) {
  159                 /* printf("GDB: got '%s'\n", gdb_rxp); */
  160                 switch (gdb_rx_char()) {
  161                 case '?':       /* Last signal. */
  162                         gdb_tx_begin('S');
  163                         gdb_tx_hex(gdb_cpu_signal(type, code), 2);
  164                         gdb_tx_end();
  165                         break;
  166                 case 'c': {     /* Continue. */
  167                         uintmax_t addr;
  168                         register_t pc;
  169                         if (!gdb_rx_varhex(&addr)) {
  170                                 pc = addr;
  171                                 gdb_cpu_setreg(GDB_REG_PC, &pc);
  172                         }
  173                         kdb_cpu_clear_singlestep();
  174                         gdb_listening = 1;
  175                         return (1);
  176                 }
  177                 case 'C': {     /* Continue with signal. */
  178                         uintmax_t addr, sig;
  179                         register_t pc;
  180                         if (!gdb_rx_varhex(&sig) && gdb_rx_char() == ';' &&
  181                             !gdb_rx_varhex(&addr)) {
  182                                 pc = addr;
  183                                 gdb_cpu_setreg(GDB_REG_PC, &pc);
  184                         }
  185                         kdb_cpu_clear_singlestep();
  186                         gdb_listening = 1;
  187                         return (1);
  188                 }
  189                 case 'D': {     /* Detach */
  190                         gdb_tx_ok();
  191                         kdb_cpu_clear_singlestep();
  192                         return (1);
  193                 }
  194                 case 'g': {     /* Read registers. */
  195                         size_t r;
  196                         gdb_tx_begin(0);
  197                         for (r = 0; r < GDB_NREGS; r++)
  198                                 gdb_tx_reg(r);
  199                         gdb_tx_end();
  200                         break;
  201                 }
  202                 case 'G':       /* Write registers. */
  203                         gdb_tx_err(0);
  204                         break;
  205                 case 'H': {     /* Set thread. */
  206                         intmax_t tid;
  207                         struct thread *thr;
  208                         gdb_rx_char();
  209                         if (gdb_rx_varhex(&tid)) {
  210                                 gdb_tx_err(EINVAL);
  211                                 break;
  212                         }
  213                         if (tid > 0) {
  214                                 thr = kdb_thr_lookup(tid);
  215                                 if (thr == NULL) {
  216                                         gdb_tx_err(ENOENT);
  217                                         break;
  218                                 }
  219                                 kdb_thr_select(thr);
  220                         }
  221                         gdb_tx_ok();
  222                         break;
  223                 }
  224                 case 'k':       /* Kill request. */
  225                         kdb_cpu_clear_singlestep();
  226                         gdb_listening = 1;
  227                         return (1);
  228                 case 'm': {     /* Read memory. */
  229                         uintmax_t addr, size;
  230                         if (gdb_rx_varhex(&addr) || gdb_rx_char() != ',' ||
  231                             gdb_rx_varhex(&size)) {
  232                                 gdb_tx_err(EINVAL);
  233                                 break;
  234                         }
  235                         gdb_tx_begin(0);
  236                         if (gdb_tx_mem((char *)(uintptr_t)addr, size))
  237                                 gdb_tx_end();
  238                         else
  239                                 gdb_tx_err(EIO);
  240                         break;
  241                 }
  242                 case 'M': {     /* Write memory. */
  243                         uintmax_t addr, size;
  244                         if (gdb_rx_varhex(&addr) || gdb_rx_char() != ',' ||
  245                             gdb_rx_varhex(&size) || gdb_rx_char() != ':') {
  246                                 gdb_tx_err(EINVAL);
  247                                 break;
  248                         }
  249                         if (gdb_rx_mem((char *)(uintptr_t)addr, size) == 0)
  250                                 gdb_tx_err(EIO);
  251                         else
  252                                 gdb_tx_ok();
  253                         break;
  254                 }
  255                 case 'P': {     /* Write register. */
  256                         char *val;
  257                         uintmax_t reg;
  258                         val = gdb_rxp;
  259                         if (gdb_rx_varhex(&reg) || gdb_rx_char() != '=' ||
  260                             !gdb_rx_mem(val, gdb_cpu_regsz(reg))) {
  261                                 gdb_tx_err(EINVAL);
  262                                 break;
  263                         }
  264                         gdb_cpu_setreg(reg, val);
  265                         gdb_tx_ok();
  266                         break;
  267                 }
  268                 case 'q':       /* General query. */
  269                         if (gdb_rx_equal("fThreadInfo")) {
  270                                 thr_iter = kdb_thr_first();
  271                                 gdb_tx_begin('m');
  272                                 gdb_tx_hex((long)thr_iter->td_tid, 8);
  273                                 gdb_tx_end();
  274                         } else if (gdb_rx_equal("sThreadInfo")) {
  275                                 if (thr_iter == NULL) {
  276                                         gdb_tx_err(ENXIO);
  277                                         break;
  278                                 }
  279                                 thr_iter = kdb_thr_next(thr_iter);
  280                                 if (thr_iter != NULL) {
  281                                         gdb_tx_begin('m');
  282                                         gdb_tx_hex((long)thr_iter->td_tid, 8);
  283                                         gdb_tx_end();
  284                                 } else {
  285                                         gdb_tx_begin('l');
  286                                         gdb_tx_end();
  287                                 }
  288                         } else if (gdb_rx_equal("Search:memory:")) {
  289                                 gdb_do_mem_search();
  290                         } else if (!gdb_cpu_query())
  291                                 gdb_tx_empty();
  292                         break;
  293                 case 's': {     /* Step. */
  294                         uintmax_t addr;
  295                         register_t pc;
  296                         if (!gdb_rx_varhex(&addr)) {
  297                                 pc = addr;
  298                                 gdb_cpu_setreg(GDB_REG_PC, &pc);
  299                         }
  300                         kdb_cpu_set_singlestep();
  301                         gdb_listening = 1;
  302                         return (1);
  303                 }
  304                 case 'S': {     /* Step with signal. */
  305                         uintmax_t addr, sig;
  306                         register_t pc;
  307                         if (!gdb_rx_varhex(&sig) && gdb_rx_char() == ';' &&
  308                             !gdb_rx_varhex(&addr)) {
  309                                 pc = addr;
  310                                 gdb_cpu_setreg(GDB_REG_PC, &pc);
  311                         }
  312                         kdb_cpu_set_singlestep();
  313                         gdb_listening = 1;
  314                         return (1);
  315                 }
  316                 case 'T': {     /* Thread alive. */
  317                         intmax_t tid;
  318                         if (gdb_rx_varhex(&tid)) {
  319                                 gdb_tx_err(EINVAL);
  320                                 break;
  321                         }
  322                         if (kdb_thr_lookup(tid) != NULL)
  323                                 gdb_tx_ok();
  324                         else
  325                                 gdb_tx_err(ENOENT);
  326                         break;
  327                 }
  328                 case -1:
  329                         /* Empty command. Treat as unknown command. */
  330                         /* FALLTHROUGH */
  331                 default:
  332                         /* Unknown command. Send empty response. */
  333                         gdb_tx_empty();
  334                         break;
  335                 }
  336         }
  337         (void)kdb_jmpbuf(prev_jb);
  338         return (0);
  339 }

Cache object: 075789de20a7ae7bf1d11d2952e3a8b9


[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]


This page is part of the FreeBSD/Linux Linux Kernel Cross-Reference, and was automatically generated using a modified version of the LXR engine.