1 /* 2 * x86 gdb server stub 3 * 4 * Copyright (c) 2003-2005 Fabrice Bellard 5 * Copyright (c) 2013 SUSE LINUX Products GmbH 6 * 7 * This library is free software; you can redistribute it and/or 8 * modify it under the terms of the GNU Lesser General Public 9 * License as published by the Free Software Foundation; either 10 * version 2 of the License, or (at your option) any later version. 11 * 12 * This library is distributed in the hope that it will be useful, 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 15 * Lesser General Public License for more details. 16 * 17 * You should have received a copy of the GNU Lesser General Public 18 * License along with this library; if not, see <http://www.gnu.org/licenses/>. 19 */ 20 #include "qemu/osdep.h" 21 #include "cpu.h" 22 #include "exec/gdbstub.h" 23 24 #ifdef TARGET_X86_64 25 static const int gpr_map[16] = { 26 R_EAX, R_EBX, R_ECX, R_EDX, R_ESI, R_EDI, R_EBP, R_ESP, 27 8, 9, 10, 11, 12, 13, 14, 15 28 }; 29 #else 30 #define gpr_map gpr_map32 31 #endif 32 static const int gpr_map32[8] = { 0, 1, 2, 3, 4, 5, 6, 7 }; 33 34 /* 35 * Keep these in sync with assignment to 36 * gdb_num_core_regs in target/i386/cpu.c 37 * and with the machine description 38 */ 39 40 /* 41 * SEG: 6 segments, plus fs_base, gs_base, kernel_gs_base 42 */ 43 44 /* 45 * general regs -----> 8 or 16 46 */ 47 #define IDX_NB_IP 1 48 #define IDX_NB_FLAGS 1 49 #define IDX_NB_SEG (6 + 3) 50 #define IDX_NB_CTL 6 51 #define IDX_NB_FP 16 52 /* 53 * fpu regs ----------> 8 or 16 54 */ 55 #define IDX_NB_MXCSR 1 56 /* 57 * total ----> 8+1+1+9+6+16+8+1=50 or 16+1+1+9+6+16+16+1=66 58 */ 59 60 #define IDX_IP_REG CPU_NB_REGS 61 #define IDX_FLAGS_REG (IDX_IP_REG + IDX_NB_IP) 62 #define IDX_SEG_REGS (IDX_FLAGS_REG + IDX_NB_FLAGS) 63 #define IDX_CTL_REGS (IDX_SEG_REGS + IDX_NB_SEG) 64 #define IDX_FP_REGS (IDX_CTL_REGS + IDX_NB_CTL) 65 #define IDX_XMM_REGS (IDX_FP_REGS + IDX_NB_FP) 66 #define IDX_MXCSR_REG (IDX_XMM_REGS + CPU_NB_REGS) 67 68 #define IDX_CTL_CR0_REG (IDX_CTL_REGS + 0) 69 #define IDX_CTL_CR2_REG (IDX_CTL_REGS + 1) 70 #define IDX_CTL_CR3_REG (IDX_CTL_REGS + 2) 71 #define IDX_CTL_CR4_REG (IDX_CTL_REGS + 3) 72 #define IDX_CTL_CR8_REG (IDX_CTL_REGS + 4) 73 #define IDX_CTL_EFER_REG (IDX_CTL_REGS + 5) 74 75 #ifdef TARGET_X86_64 76 #define GDB_FORCE_64 1 77 #else 78 #define GDB_FORCE_64 0 79 #endif 80 81 82 int x86_cpu_gdb_read_register(CPUState *cs, uint8_t *mem_buf, int n) 83 { 84 X86CPU *cpu = X86_CPU(cs); 85 CPUX86State *env = &cpu->env; 86 87 uint64_t tpr; 88 89 /* N.B. GDB can't deal with changes in registers or sizes in the middle 90 of a session. So if we're in 32-bit mode on a 64-bit cpu, still act 91 as if we're on a 64-bit cpu. */ 92 93 if (n < CPU_NB_REGS) { 94 if (TARGET_LONG_BITS == 64) { 95 if (env->hflags & HF_CS64_MASK) { 96 return gdb_get_reg64(mem_buf, env->regs[gpr_map[n]]); 97 } else if (n < CPU_NB_REGS32) { 98 return gdb_get_reg64(mem_buf, 99 env->regs[gpr_map[n]] & 0xffffffffUL); 100 } else { 101 memset(mem_buf, 0, sizeof(target_ulong)); 102 return sizeof(target_ulong); 103 } 104 } else { 105 return gdb_get_reg32(mem_buf, env->regs[gpr_map32[n]]); 106 } 107 } else if (n >= IDX_FP_REGS && n < IDX_FP_REGS + 8) { 108 #ifdef USE_X86LDOUBLE 109 /* FIXME: byteswap float values - after fixing fpregs layout. */ 110 memcpy(mem_buf, &env->fpregs[n - IDX_FP_REGS], 10); 111 #else 112 memset(mem_buf, 0, 10); 113 #endif 114 return 10; 115 } else if (n >= IDX_XMM_REGS && n < IDX_XMM_REGS + CPU_NB_REGS) { 116 n -= IDX_XMM_REGS; 117 if (n < CPU_NB_REGS32 || TARGET_LONG_BITS == 64) { 118 stq_p(mem_buf, env->xmm_regs[n].ZMM_Q(0)); 119 stq_p(mem_buf + 8, env->xmm_regs[n].ZMM_Q(1)); 120 return 16; 121 } 122 } else { 123 switch (n) { 124 case IDX_IP_REG: 125 if (TARGET_LONG_BITS == 64) { 126 if (env->hflags & HF_CS64_MASK) { 127 return gdb_get_reg64(mem_buf, env->eip); 128 } else { 129 return gdb_get_reg64(mem_buf, env->eip & 0xffffffffUL); 130 } 131 } else { 132 return gdb_get_reg32(mem_buf, env->eip); 133 } 134 case IDX_FLAGS_REG: 135 return gdb_get_reg32(mem_buf, env->eflags); 136 137 case IDX_SEG_REGS: 138 return gdb_get_reg32(mem_buf, env->segs[R_CS].selector); 139 case IDX_SEG_REGS + 1: 140 return gdb_get_reg32(mem_buf, env->segs[R_SS].selector); 141 case IDX_SEG_REGS + 2: 142 return gdb_get_reg32(mem_buf, env->segs[R_DS].selector); 143 case IDX_SEG_REGS + 3: 144 return gdb_get_reg32(mem_buf, env->segs[R_ES].selector); 145 case IDX_SEG_REGS + 4: 146 return gdb_get_reg32(mem_buf, env->segs[R_FS].selector); 147 case IDX_SEG_REGS + 5: 148 return gdb_get_reg32(mem_buf, env->segs[R_GS].selector); 149 150 case IDX_SEG_REGS + 6: 151 if ((env->hflags & HF_CS64_MASK) || GDB_FORCE_64) { 152 return gdb_get_reg64(mem_buf, env->segs[R_FS].base); 153 } 154 return gdb_get_reg32(mem_buf, env->segs[R_FS].base); 155 156 case IDX_SEG_REGS + 7: 157 if ((env->hflags & HF_CS64_MASK) || GDB_FORCE_64) { 158 return gdb_get_reg64(mem_buf, env->segs[R_GS].base); 159 } 160 return gdb_get_reg32(mem_buf, env->segs[R_GS].base); 161 162 case IDX_SEG_REGS + 8: 163 #ifdef TARGET_X86_64 164 if ((env->hflags & HF_CS64_MASK) || GDB_FORCE_64) { 165 return gdb_get_reg64(mem_buf, env->kernelgsbase); 166 } 167 return gdb_get_reg32(mem_buf, env->kernelgsbase); 168 #else 169 return gdb_get_reg32(mem_buf, 0); 170 #endif 171 172 case IDX_FP_REGS + 8: 173 return gdb_get_reg32(mem_buf, env->fpuc); 174 case IDX_FP_REGS + 9: 175 return gdb_get_reg32(mem_buf, (env->fpus & ~0x3800) | 176 (env->fpstt & 0x7) << 11); 177 case IDX_FP_REGS + 10: 178 return gdb_get_reg32(mem_buf, 0); /* ftag */ 179 case IDX_FP_REGS + 11: 180 return gdb_get_reg32(mem_buf, 0); /* fiseg */ 181 case IDX_FP_REGS + 12: 182 return gdb_get_reg32(mem_buf, 0); /* fioff */ 183 case IDX_FP_REGS + 13: 184 return gdb_get_reg32(mem_buf, 0); /* foseg */ 185 case IDX_FP_REGS + 14: 186 return gdb_get_reg32(mem_buf, 0); /* fooff */ 187 case IDX_FP_REGS + 15: 188 return gdb_get_reg32(mem_buf, 0); /* fop */ 189 190 case IDX_MXCSR_REG: 191 return gdb_get_reg32(mem_buf, env->mxcsr); 192 193 case IDX_CTL_CR0_REG: 194 if ((env->hflags & HF_CS64_MASK) || GDB_FORCE_64) { 195 return gdb_get_reg64(mem_buf, env->cr[0]); 196 } 197 return gdb_get_reg32(mem_buf, env->cr[0]); 198 199 case IDX_CTL_CR2_REG: 200 if ((env->hflags & HF_CS64_MASK) || GDB_FORCE_64) { 201 return gdb_get_reg64(mem_buf, env->cr[2]); 202 } 203 return gdb_get_reg32(mem_buf, env->cr[2]); 204 205 case IDX_CTL_CR3_REG: 206 if ((env->hflags & HF_CS64_MASK) || GDB_FORCE_64) { 207 return gdb_get_reg64(mem_buf, env->cr[3]); 208 } 209 return gdb_get_reg32(mem_buf, env->cr[3]); 210 211 case IDX_CTL_CR4_REG: 212 if ((env->hflags & HF_CS64_MASK) || GDB_FORCE_64) { 213 return gdb_get_reg64(mem_buf, env->cr[4]); 214 } 215 return gdb_get_reg32(mem_buf, env->cr[4]); 216 217 case IDX_CTL_CR8_REG: 218 #ifdef CONFIG_SOFTMMU 219 tpr = cpu_get_apic_tpr(cpu->apic_state); 220 #else 221 tpr = 0; 222 #endif 223 if ((env->hflags & HF_CS64_MASK) || GDB_FORCE_64) { 224 return gdb_get_reg64(mem_buf, tpr); 225 } 226 return gdb_get_reg32(mem_buf, tpr); 227 228 case IDX_CTL_EFER_REG: 229 if ((env->hflags & HF_CS64_MASK) || GDB_FORCE_64) { 230 return gdb_get_reg64(mem_buf, env->efer); 231 } 232 return gdb_get_reg32(mem_buf, env->efer); 233 } 234 } 235 return 0; 236 } 237 238 static int x86_cpu_gdb_load_seg(X86CPU *cpu, int sreg, uint8_t *mem_buf) 239 { 240 CPUX86State *env = &cpu->env; 241 uint16_t selector = ldl_p(mem_buf); 242 243 if (selector != env->segs[sreg].selector) { 244 #if defined(CONFIG_USER_ONLY) 245 cpu_x86_load_seg(env, sreg, selector); 246 #else 247 unsigned int limit, flags; 248 target_ulong base; 249 250 if (!(env->cr[0] & CR0_PE_MASK) || (env->eflags & VM_MASK)) { 251 int dpl = (env->eflags & VM_MASK) ? 3 : 0; 252 base = selector << 4; 253 limit = 0xffff; 254 flags = DESC_P_MASK | DESC_S_MASK | DESC_W_MASK | 255 DESC_A_MASK | (dpl << DESC_DPL_SHIFT); 256 } else { 257 if (!cpu_x86_get_descr_debug(env, selector, &base, &limit, 258 &flags)) { 259 return 4; 260 } 261 } 262 cpu_x86_load_seg_cache(env, sreg, selector, base, limit, flags); 263 #endif 264 } 265 return 4; 266 } 267 268 int x86_cpu_gdb_write_register(CPUState *cs, uint8_t *mem_buf, int n) 269 { 270 X86CPU *cpu = X86_CPU(cs); 271 CPUX86State *env = &cpu->env; 272 uint32_t tmp; 273 274 /* N.B. GDB can't deal with changes in registers or sizes in the middle 275 of a session. So if we're in 32-bit mode on a 64-bit cpu, still act 276 as if we're on a 64-bit cpu. */ 277 278 if (n < CPU_NB_REGS) { 279 if (TARGET_LONG_BITS == 64) { 280 if (env->hflags & HF_CS64_MASK) { 281 env->regs[gpr_map[n]] = ldtul_p(mem_buf); 282 } else if (n < CPU_NB_REGS32) { 283 env->regs[gpr_map[n]] = ldtul_p(mem_buf) & 0xffffffffUL; 284 } 285 return sizeof(target_ulong); 286 } else if (n < CPU_NB_REGS32) { 287 n = gpr_map32[n]; 288 env->regs[n] &= ~0xffffffffUL; 289 env->regs[n] |= (uint32_t)ldl_p(mem_buf); 290 return 4; 291 } 292 } else if (n >= IDX_FP_REGS && n < IDX_FP_REGS + 8) { 293 #ifdef USE_X86LDOUBLE 294 /* FIXME: byteswap float values - after fixing fpregs layout. */ 295 memcpy(&env->fpregs[n - IDX_FP_REGS], mem_buf, 10); 296 #endif 297 return 10; 298 } else if (n >= IDX_XMM_REGS && n < IDX_XMM_REGS + CPU_NB_REGS) { 299 n -= IDX_XMM_REGS; 300 if (n < CPU_NB_REGS32 || TARGET_LONG_BITS == 64) { 301 env->xmm_regs[n].ZMM_Q(0) = ldq_p(mem_buf); 302 env->xmm_regs[n].ZMM_Q(1) = ldq_p(mem_buf + 8); 303 return 16; 304 } 305 } else { 306 switch (n) { 307 case IDX_IP_REG: 308 if (TARGET_LONG_BITS == 64) { 309 if (env->hflags & HF_CS64_MASK) { 310 env->eip = ldq_p(mem_buf); 311 } else { 312 env->eip = ldq_p(mem_buf) & 0xffffffffUL; 313 } 314 return 8; 315 } else { 316 env->eip &= ~0xffffffffUL; 317 env->eip |= (uint32_t)ldl_p(mem_buf); 318 return 4; 319 } 320 case IDX_FLAGS_REG: 321 env->eflags = ldl_p(mem_buf); 322 return 4; 323 324 case IDX_SEG_REGS: 325 return x86_cpu_gdb_load_seg(cpu, R_CS, mem_buf); 326 case IDX_SEG_REGS + 1: 327 return x86_cpu_gdb_load_seg(cpu, R_SS, mem_buf); 328 case IDX_SEG_REGS + 2: 329 return x86_cpu_gdb_load_seg(cpu, R_DS, mem_buf); 330 case IDX_SEG_REGS + 3: 331 return x86_cpu_gdb_load_seg(cpu, R_ES, mem_buf); 332 case IDX_SEG_REGS + 4: 333 return x86_cpu_gdb_load_seg(cpu, R_FS, mem_buf); 334 case IDX_SEG_REGS + 5: 335 return x86_cpu_gdb_load_seg(cpu, R_GS, mem_buf); 336 337 case IDX_SEG_REGS + 6: 338 if (env->hflags & HF_CS64_MASK) { 339 env->segs[R_FS].base = ldq_p(mem_buf); 340 return 8; 341 } 342 env->segs[R_FS].base = ldl_p(mem_buf); 343 return 4; 344 345 case IDX_SEG_REGS + 7: 346 if (env->hflags & HF_CS64_MASK) { 347 env->segs[R_GS].base = ldq_p(mem_buf); 348 return 8; 349 } 350 env->segs[R_GS].base = ldl_p(mem_buf); 351 return 4; 352 353 case IDX_SEG_REGS + 8: 354 #ifdef TARGET_X86_64 355 if (env->hflags & HF_CS64_MASK) { 356 env->kernelgsbase = ldq_p(mem_buf); 357 return 8; 358 } 359 env->kernelgsbase = ldl_p(mem_buf); 360 #endif 361 return 4; 362 363 case IDX_FP_REGS + 8: 364 cpu_set_fpuc(env, ldl_p(mem_buf)); 365 return 4; 366 case IDX_FP_REGS + 9: 367 tmp = ldl_p(mem_buf); 368 env->fpstt = (tmp >> 11) & 7; 369 env->fpus = tmp & ~0x3800; 370 return 4; 371 case IDX_FP_REGS + 10: /* ftag */ 372 return 4; 373 case IDX_FP_REGS + 11: /* fiseg */ 374 return 4; 375 case IDX_FP_REGS + 12: /* fioff */ 376 return 4; 377 case IDX_FP_REGS + 13: /* foseg */ 378 return 4; 379 case IDX_FP_REGS + 14: /* fooff */ 380 return 4; 381 case IDX_FP_REGS + 15: /* fop */ 382 return 4; 383 384 case IDX_MXCSR_REG: 385 cpu_set_mxcsr(env, ldl_p(mem_buf)); 386 return 4; 387 388 case IDX_CTL_CR0_REG: 389 if (env->hflags & HF_CS64_MASK) { 390 cpu_x86_update_cr0(env, ldq_p(mem_buf)); 391 return 8; 392 } 393 cpu_x86_update_cr0(env, ldl_p(mem_buf)); 394 return 4; 395 396 case IDX_CTL_CR2_REG: 397 if (env->hflags & HF_CS64_MASK) { 398 env->cr[2] = ldq_p(mem_buf); 399 return 8; 400 } 401 env->cr[2] = ldl_p(mem_buf); 402 return 4; 403 404 case IDX_CTL_CR3_REG: 405 if (env->hflags & HF_CS64_MASK) { 406 cpu_x86_update_cr3(env, ldq_p(mem_buf)); 407 return 8; 408 } 409 cpu_x86_update_cr3(env, ldl_p(mem_buf)); 410 return 4; 411 412 case IDX_CTL_CR4_REG: 413 if (env->hflags & HF_CS64_MASK) { 414 cpu_x86_update_cr4(env, ldq_p(mem_buf)); 415 return 8; 416 } 417 cpu_x86_update_cr4(env, ldl_p(mem_buf)); 418 return 4; 419 420 case IDX_CTL_CR8_REG: 421 if (env->hflags & HF_CS64_MASK) { 422 #ifdef CONFIG_SOFTMMU 423 cpu_set_apic_tpr(cpu->apic_state, ldq_p(mem_buf)); 424 #endif 425 return 8; 426 } 427 #ifdef CONFIG_SOFTMMU 428 cpu_set_apic_tpr(cpu->apic_state, ldl_p(mem_buf)); 429 #endif 430 return 4; 431 432 case IDX_CTL_EFER_REG: 433 if (env->hflags & HF_CS64_MASK) { 434 cpu_load_efer(env, ldq_p(mem_buf)); 435 return 8; 436 } 437 cpu_load_efer(env, ldl_p(mem_buf)); 438 return 4; 439 440 } 441 } 442 /* Unrecognised register. */ 443 return 0; 444 } 445