1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 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("$FreeBSD$"); 31 32 #include <sys/param.h> 33 #include <sys/systm.h> 34 #include <sys/kdb.h> 35 #include <sys/kernel.h> 36 #include <sys/proc.h> 37 #include <sys/reg.h> 38 #include <sys/signal.h> 39 40 #include <machine/endian.h> 41 #include <machine/frame.h> 42 #include <machine/gdb_machdep.h> 43 #include <machine/pcb.h> 44 #include <machine/trap.h> 45 46 #include <gdb/gdb.h> 47 #include <gdb/gdb_int.h> 48 49 void * 50 gdb_cpu_getreg(int regnum, size_t *regsz) 51 { 52 static uint32_t _kcodesel = GSEL(GCODE_SEL, SEL_KPL); 53 static uint32_t _kdatasel = GSEL(GDATA_SEL, SEL_KPL); 54 static uint32_t _kprivsel = GSEL(GPRIV_SEL, SEL_KPL); 55 56 *regsz = gdb_cpu_regsz(regnum); 57 58 if (kdb_thread == curthread) { 59 switch (regnum) { 60 case 0: return (&kdb_frame->tf_eax); 61 case 1: return (&kdb_frame->tf_ecx); 62 case 2: return (&kdb_frame->tf_edx); 63 case 9: return (&kdb_frame->tf_eflags); 64 case 10: return (&kdb_frame->tf_cs); 65 case 12: return (&kdb_frame->tf_ds); 66 case 13: return (&kdb_frame->tf_es); 67 case 14: return (&kdb_frame->tf_fs); 68 } 69 } 70 switch (regnum) { 71 case 3: return (&kdb_thrctx->pcb_ebx); 72 case 4: return (&kdb_thrctx->pcb_esp); 73 case 5: return (&kdb_thrctx->pcb_ebp); 74 case 6: return (&kdb_thrctx->pcb_esi); 75 case 7: return (&kdb_thrctx->pcb_edi); 76 case 8: return (&kdb_thrctx->pcb_eip); 77 case 10: return (&_kcodesel); 78 case 11: return (&_kdatasel); 79 case 12: return (&_kdatasel); 80 case 13: return (&_kdatasel); 81 case 14: return (&_kprivsel); 82 case 15: return (&kdb_thrctx->pcb_gs); 83 } 84 return (NULL); 85 } 86 87 void 88 gdb_cpu_setreg(int regnum, void *val) 89 { 90 91 switch (regnum) { 92 case GDB_REG_PC: 93 kdb_thrctx->pcb_eip = *(register_t *)val; 94 if (kdb_thread == curthread) 95 kdb_frame->tf_eip = *(register_t *)val; 96 } 97 } 98 99 int 100 gdb_cpu_signal(int type, int code) 101 { 102 103 switch (type) { 104 case T_BPTFLT: return (SIGTRAP); 105 case T_ARITHTRAP: return (SIGFPE); 106 case T_PROTFLT: return (SIGSEGV); 107 case T_TRCTRAP: return (SIGTRAP); 108 case T_PAGEFLT: return (SIGSEGV); 109 case T_DIVIDE: return (SIGFPE); 110 case T_NMI: return (SIGTRAP); 111 case T_FPOPFLT: return (SIGILL); 112 case T_TSSFLT: return (SIGSEGV); 113 case T_SEGNPFLT: return (SIGSEGV); 114 case T_STKFLT: return (SIGSEGV); 115 case T_XMMFLT: return (SIGFPE); 116 } 117 return (SIGEMT); 118 } 119 120 void 121 gdb_cpu_stop_reason(int type, int code) 122 { 123 uintmax_t val; 124 125 val = 0; 126 if (type == T_TRCTRAP) { 127 /* NB: 'code' contains the value of dr6 at the trap. */ 128 if ((code & DBREG_DR6_B(0)) != 0) { 129 val = rdr0(); 130 } 131 if ((code & DBREG_DR6_B(1)) != 0) { 132 val = rdr1(); 133 } 134 if ((code & DBREG_DR6_B(2)) != 0) { 135 val = rdr2(); 136 } 137 if ((code & DBREG_DR6_B(3)) != 0) { 138 val = rdr3(); 139 } 140 141 /* 142 * TODO: validate the bits in DR7 to differentiate between a 143 * watchpoint trap and a hardware breakpoint trap (currently 144 * unsupported). 145 */ 146 if (val != 0) { 147 gdb_tx_str("watch:"); 148 gdb_tx_varhex(val); 149 gdb_tx_char(';'); 150 } 151 } 152 } 153