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("$FreeBSD$"); 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/cpufunc.h> 41 #include <machine/frame.h> 42 #include <machine/gdb_machdep.h> 43 #include <machine/md_var.h> 44 #include <machine/pcb.h> 45 #include <machine/psl.h> 46 #include <machine/specialreg.h> 47 #include <machine/trap.h> 48 #include <machine/frame.h> 49 #include <machine/endian.h> 50 51 #include <gdb/gdb.h> 52 #include <gdb/gdb_int.h> 53 54 void * 55 gdb_cpu_getreg(int regnum, size_t *regsz) 56 { 57 static uint32_t _kcodesel = GSEL(GCODE_SEL, SEL_KPL); 58 static uint32_t _kdatasel = GSEL(GDATA_SEL, SEL_KPL); 59 60 *regsz = gdb_cpu_regsz(regnum); 61 62 if (kdb_thread == curthread) { 63 switch (regnum) { 64 case GDB_REG_RAX: return (&kdb_frame->tf_rax); 65 case GDB_REG_RCX: return (&kdb_frame->tf_rcx); 66 case GDB_REG_RDX: return (&kdb_frame->tf_rdx); 67 case GDB_REG_RSI: return (&kdb_frame->tf_rsi); 68 case GDB_REG_RDI: return (&kdb_frame->tf_rdi); 69 case GDB_REG_R8: return (&kdb_frame->tf_r8); 70 case GDB_REG_R9: return (&kdb_frame->tf_r9); 71 case GDB_REG_R10: return (&kdb_frame->tf_r10); 72 case GDB_REG_R11: return (&kdb_frame->tf_r11); 73 case GDB_REG_RFLAGS: return (&kdb_frame->tf_rflags); 74 case GDB_REG_CS: return (&kdb_frame->tf_cs); 75 case GDB_REG_SS: return (&kdb_frame->tf_ss); 76 } 77 } 78 switch (regnum) { 79 case GDB_REG_RBX: return (&kdb_thrctx->pcb_rbx); 80 case GDB_REG_RBP: return (&kdb_thrctx->pcb_rbp); 81 case GDB_REG_RSP: return (&kdb_thrctx->pcb_rsp); 82 case GDB_REG_R12: return (&kdb_thrctx->pcb_r12); 83 case GDB_REG_R13: return (&kdb_thrctx->pcb_r13); 84 case GDB_REG_R14: return (&kdb_thrctx->pcb_r14); 85 case GDB_REG_R15: return (&kdb_thrctx->pcb_r15); 86 case GDB_REG_PC: return (&kdb_thrctx->pcb_rip); 87 case GDB_REG_CS: return (&_kcodesel); 88 case GDB_REG_SS: return (&_kdatasel); 89 } 90 return (NULL); 91 } 92 93 void 94 gdb_cpu_setreg(int regnum, void *val) 95 { 96 register_t regval = *(register_t *)val; 97 98 /* 99 * Write registers to the trapframe and pcb, if applicable. 100 * Some scratch registers are not tracked by the pcb. 101 */ 102 if (kdb_thread == curthread) { 103 switch (regnum) { 104 case GDB_REG_RAX: kdb_frame->tf_rax = regval; break; 105 case GDB_REG_RBX: kdb_frame->tf_rbx = regval; break; 106 case GDB_REG_RCX: kdb_frame->tf_rcx = regval; break; 107 case GDB_REG_RDX: kdb_frame->tf_rdx = regval; break; 108 case GDB_REG_RSI: kdb_frame->tf_rsi = regval; break; 109 case GDB_REG_RDI: kdb_frame->tf_rdi = regval; break; 110 case GDB_REG_RBP: kdb_frame->tf_rbp = regval; break; 111 case GDB_REG_RSP: kdb_frame->tf_rsp = regval; break; 112 case GDB_REG_R8: kdb_frame->tf_r8 = regval; break; 113 case GDB_REG_R9: kdb_frame->tf_r9 = regval; break; 114 case GDB_REG_R10: kdb_frame->tf_r10 = regval; break; 115 case GDB_REG_R11: kdb_frame->tf_r11 = regval; break; 116 case GDB_REG_R12: kdb_frame->tf_r12 = regval; break; 117 case GDB_REG_R13: kdb_frame->tf_r13 = regval; break; 118 case GDB_REG_R14: kdb_frame->tf_r14 = regval; break; 119 case GDB_REG_R15: kdb_frame->tf_r15 = regval; break; 120 case GDB_REG_PC: kdb_frame->tf_rip = regval; break; 121 } 122 } 123 switch (regnum) { 124 case GDB_REG_RBX: kdb_thrctx->pcb_rbx = regval; break; 125 case GDB_REG_RBP: kdb_thrctx->pcb_rbp = regval; break; 126 case GDB_REG_RSP: kdb_thrctx->pcb_rsp = regval; break; 127 case GDB_REG_R12: kdb_thrctx->pcb_r12 = regval; break; 128 case GDB_REG_R13: kdb_thrctx->pcb_r13 = regval; break; 129 case GDB_REG_R14: kdb_thrctx->pcb_r14 = regval; break; 130 case GDB_REG_R15: kdb_thrctx->pcb_r15 = regval; break; 131 case GDB_REG_PC: kdb_thrctx->pcb_rip = regval; break; 132 } 133 } 134 135 int 136 gdb_cpu_signal(int type, int code) 137 { 138 139 switch (type) { 140 case T_BPTFLT: return (SIGTRAP); 141 case T_ARITHTRAP: return (SIGFPE); 142 case T_PROTFLT: return (SIGSEGV); 143 case T_TRCTRAP: return (SIGTRAP); 144 case T_PAGEFLT: return (SIGSEGV); 145 case T_DIVIDE: return (SIGFPE); 146 case T_NMI: return (SIGTRAP); 147 case T_FPOPFLT: return (SIGILL); 148 case T_TSSFLT: return (SIGSEGV); 149 case T_SEGNPFLT: return (SIGSEGV); 150 case T_STKFLT: return (SIGSEGV); 151 case T_XMMFLT: return (SIGFPE); 152 } 153 return (SIGEMT); 154 } 155 156 void 157 gdb_cpu_stop_reason(int type, int code) 158 { 159 uintmax_t val; 160 161 val = 0; 162 if (type == T_TRCTRAP) { 163 /* NB: 'code' contains the value of dr6 at the trap. */ 164 if ((code & DBREG_DR6_B(0)) != 0) { 165 val = rdr0(); 166 } 167 if ((code & DBREG_DR6_B(1)) != 0) { 168 val = rdr1(); 169 } 170 if ((code & DBREG_DR6_B(2)) != 0) { 171 val = rdr2(); 172 } 173 if ((code & DBREG_DR6_B(3)) != 0) { 174 val = rdr3(); 175 } 176 177 /* 178 * TODO: validate the bits in DR7 to differentiate between a 179 * watchpoint trap and a hardware breakpoint trap (currently 180 * unsupported). 181 */ 182 if (val != 0) { 183 gdb_tx_str("watch:"); 184 gdb_tx_varhex(val); 185 gdb_tx_char(';'); 186 } 187 } 188 } 189 190 void * 191 gdb_begin_write(void) 192 { 193 194 return (disable_wp() ? &gdb_begin_write : NULL); 195 } 196 197 void 198 gdb_end_write(void *arg) 199 { 200 201 restore_wp(arg != NULL); 202 } 203