1 0 stevel /* 2 0 stevel * CDDL HEADER START 3 0 stevel * 4 0 stevel * The contents of this file are subject to the terms of the 5 5084 johnlev * Common Development and Distribution License (the "License"). 6 5084 johnlev * You may not use this file except in compliance with the License. 7 0 stevel * 8 0 stevel * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 0 stevel * or http://www.opensolaris.org/os/licensing. 10 0 stevel * See the License for the specific language governing permissions 11 0 stevel * and limitations under the License. 12 0 stevel * 13 0 stevel * When distributing Covered Code, include this CDDL HEADER in each 14 0 stevel * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 0 stevel * If applicable, add the following below this CDDL HEADER, with the 16 0 stevel * fields enclosed by brackets "[]" replaced with your own identifying 17 0 stevel * information: Portions Copyright [yyyy] [name of copyright owner] 18 0 stevel * 19 0 stevel * CDDL HEADER END 20 0 stevel */ 21 0 stevel /* 22 5084 johnlev * Copyright 2007 Sun Microsystems, Inc. All rights reserved. 23 0 stevel * Use is subject to license terms. 24 0 stevel */ 25 0 stevel 26 0 stevel #pragma ident "%Z%%M% %I% %E% SMI" 27 0 stevel 28 0 stevel #include <sys/types.h> 29 0 stevel #include <sys/reg.h> 30 0 stevel #include <sys/privregs.h> 31 0 stevel #include <sys/stack.h> 32 0 stevel #include <sys/frame.h> 33 0 stevel 34 0 stevel #include <mdb/mdb_ia32util.h> 35 0 stevel #include <mdb/mdb_target_impl.h> 36 0 stevel #include <mdb/mdb_kreg_impl.h> 37 0 stevel #include <mdb/mdb_debug.h> 38 0 stevel #include <mdb/mdb_modapi.h> 39 0 stevel #include <mdb/mdb_err.h> 40 0 stevel #include <mdb/mdb.h> 41 0 stevel 42 0 stevel /* 43 0 stevel * We also define an array of register names and their corresponding 44 0 stevel * array indices. This is used by the getareg and putareg entry points, 45 0 stevel * and also by our register variable discipline. 46 0 stevel */ 47 0 stevel const mdb_tgt_regdesc_t mdb_ia32_kregs[] = { 48 0 stevel { "savfp", KREG_SAVFP, MDB_TGT_R_EXPORT }, 49 0 stevel { "savpc", KREG_SAVPC, MDB_TGT_R_EXPORT }, 50 0 stevel { "eax", KREG_EAX, MDB_TGT_R_EXPORT }, 51 0 stevel { "ebx", KREG_EBX, MDB_TGT_R_EXPORT }, 52 0 stevel { "ecx", KREG_ECX, MDB_TGT_R_EXPORT }, 53 0 stevel { "edx", KREG_EDX, MDB_TGT_R_EXPORT }, 54 0 stevel { "esi", KREG_ESI, MDB_TGT_R_EXPORT }, 55 0 stevel { "edi", KREG_EDI, MDB_TGT_R_EXPORT }, 56 0 stevel { "ebp", KREG_EBP, MDB_TGT_R_EXPORT }, 57 0 stevel { "esp", KREG_ESP, MDB_TGT_R_EXPORT }, 58 0 stevel { "cs", KREG_CS, MDB_TGT_R_EXPORT }, 59 0 stevel { "ds", KREG_DS, MDB_TGT_R_EXPORT }, 60 0 stevel { "ss", KREG_SS, MDB_TGT_R_EXPORT }, 61 0 stevel { "es", KREG_ES, MDB_TGT_R_EXPORT }, 62 0 stevel { "fs", KREG_FS, MDB_TGT_R_EXPORT }, 63 0 stevel { "gs", KREG_GS, MDB_TGT_R_EXPORT }, 64 0 stevel { "eflags", KREG_EFLAGS, MDB_TGT_R_EXPORT }, 65 0 stevel { "eip", KREG_EIP, MDB_TGT_R_EXPORT }, 66 0 stevel { "uesp", KREG_UESP, MDB_TGT_R_EXPORT | MDB_TGT_R_PRIV }, 67 0 stevel { "trapno", KREG_TRAPNO, MDB_TGT_R_EXPORT | MDB_TGT_R_PRIV }, 68 0 stevel { "err", KREG_ERR, MDB_TGT_R_EXPORT | MDB_TGT_R_PRIV }, 69 0 stevel { NULL, 0, 0 } 70 0 stevel }; 71 0 stevel 72 0 stevel void 73 0 stevel mdb_ia32_printregs(const mdb_tgt_gregset_t *gregs) 74 0 stevel { 75 0 stevel const kreg_t *kregs = &gregs->kregs[0]; 76 0 stevel kreg_t eflags = kregs[KREG_EFLAGS]; 77 0 stevel 78 0 stevel mdb_printf("%%cs = 0x%04x\t\t%%eax = 0x%0?p %A\n", 79 0 stevel kregs[KREG_CS], kregs[KREG_EAX], kregs[KREG_EAX]); 80 0 stevel 81 0 stevel mdb_printf("%%ds = 0x%04x\t\t%%ebx = 0x%0?p %A\n", 82 0 stevel kregs[KREG_DS], kregs[KREG_EBX], kregs[KREG_EBX]); 83 0 stevel 84 0 stevel mdb_printf("%%ss = 0x%04x\t\t%%ecx = 0x%0?p %A\n", 85 0 stevel kregs[KREG_SS], kregs[KREG_ECX], kregs[KREG_ECX]); 86 0 stevel 87 0 stevel mdb_printf("%%es = 0x%04x\t\t%%edx = 0x%0?p %A\n", 88 0 stevel kregs[KREG_ES], kregs[KREG_EDX], kregs[KREG_EDX]); 89 0 stevel 90 0 stevel mdb_printf("%%fs = 0x%04x\t\t%%esi = 0x%0?p %A\n", 91 0 stevel kregs[KREG_FS], kregs[KREG_ESI], kregs[KREG_ESI]); 92 0 stevel 93 0 stevel mdb_printf("%%gs = 0x%04x\t\t%%edi = 0x%0?p %A\n\n", 94 0 stevel kregs[KREG_GS], kregs[KREG_EDI], kregs[KREG_EDI]); 95 0 stevel 96 0 stevel mdb_printf("%%eip = 0x%0?p %A\n", kregs[KREG_EIP], kregs[KREG_EIP]); 97 0 stevel mdb_printf("%%ebp = 0x%0?p\n", kregs[KREG_EBP]); 98 0 stevel mdb_printf("%%esp = 0x%0?p\n\n", kregs[KREG_ESP]); 99 0 stevel mdb_printf("%%eflags = 0x%08x\n", eflags); 100 0 stevel 101 0 stevel mdb_printf(" id=%u vip=%u vif=%u ac=%u vm=%u rf=%u nt=%u iopl=0x%x\n", 102 0 stevel (eflags & KREG_EFLAGS_ID_MASK) >> KREG_EFLAGS_ID_SHIFT, 103 0 stevel (eflags & KREG_EFLAGS_VIP_MASK) >> KREG_EFLAGS_VIP_SHIFT, 104 0 stevel (eflags & KREG_EFLAGS_VIF_MASK) >> KREG_EFLAGS_VIF_SHIFT, 105 0 stevel (eflags & KREG_EFLAGS_AC_MASK) >> KREG_EFLAGS_AC_SHIFT, 106 0 stevel (eflags & KREG_EFLAGS_VM_MASK) >> KREG_EFLAGS_VM_SHIFT, 107 0 stevel (eflags & KREG_EFLAGS_RF_MASK) >> KREG_EFLAGS_RF_SHIFT, 108 0 stevel (eflags & KREG_EFLAGS_NT_MASK) >> KREG_EFLAGS_NT_SHIFT, 109 0 stevel (eflags & KREG_EFLAGS_IOPL_MASK) >> KREG_EFLAGS_IOPL_SHIFT); 110 0 stevel 111 0 stevel mdb_printf(" status=<%s,%s,%s,%s,%s,%s,%s,%s,%s>\n\n", 112 0 stevel (eflags & KREG_EFLAGS_OF_MASK) ? "OF" : "of", 113 0 stevel (eflags & KREG_EFLAGS_DF_MASK) ? "DF" : "df", 114 0 stevel (eflags & KREG_EFLAGS_IF_MASK) ? "IF" : "if", 115 0 stevel (eflags & KREG_EFLAGS_TF_MASK) ? "TF" : "tf", 116 0 stevel (eflags & KREG_EFLAGS_SF_MASK) ? "SF" : "sf", 117 0 stevel (eflags & KREG_EFLAGS_ZF_MASK) ? "ZF" : "zf", 118 0 stevel (eflags & KREG_EFLAGS_AF_MASK) ? "AF" : "af", 119 0 stevel (eflags & KREG_EFLAGS_PF_MASK) ? "PF" : "pf", 120 0 stevel (eflags & KREG_EFLAGS_CF_MASK) ? "CF" : "cf"); 121 0 stevel 122 0 stevel #ifndef _KMDB 123 0 stevel mdb_printf(" %%uesp = 0x%0?x\n", kregs[KREG_UESP]); 124 0 stevel #endif 125 0 stevel mdb_printf("%%trapno = 0x%x\n", kregs[KREG_TRAPNO]); 126 0 stevel mdb_printf(" %%err = 0x%x\n", kregs[KREG_ERR]); 127 0 stevel } 128 0 stevel 129 0 stevel /* 130 0 stevel * Given a return address (%eip), determine the likely number of arguments 131 0 stevel * that were pushed on the stack prior to its execution. We do this by 132 0 stevel * expecting that a typical call sequence consists of pushing arguments on 133 0 stevel * the stack, executing a call instruction, and then performing an add 134 0 stevel * on %esp to restore it to the value prior to pushing the arguments for 135 0 stevel * the call. We attempt to detect such an add, and divide the addend 136 0 stevel * by the size of a word to determine the number of pushed arguments. 137 0 stevel */ 138 0 stevel static uint_t 139 0 stevel kvm_argcount(mdb_tgt_t *t, uintptr_t eip, ssize_t size) 140 0 stevel { 141 0 stevel uint8_t ins[6]; 142 0 stevel ulong_t n; 143 0 stevel 144 0 stevel enum { 145 0 stevel M_MODRM_ESP = 0xc4, /* Mod/RM byte indicates %esp */ 146 0 stevel M_ADD_IMM32 = 0x81, /* ADD imm32 to r/m32 */ 147 0 stevel M_ADD_IMM8 = 0x83 /* ADD imm8 to r/m32 */ 148 0 stevel }; 149 0 stevel 150 0 stevel if (mdb_tgt_vread(t, ins, sizeof (ins), eip) != sizeof (ins)) 151 0 stevel return (0); 152 0 stevel 153 0 stevel if (ins[1] != M_MODRM_ESP) 154 0 stevel return (0); 155 0 stevel 156 0 stevel switch (ins[0]) { 157 0 stevel case M_ADD_IMM32: 158 0 stevel n = ins[2] + (ins[3] << 8) + (ins[4] << 16) + (ins[5] << 24); 159 0 stevel break; 160 0 stevel 161 0 stevel case M_ADD_IMM8: 162 0 stevel n = ins[2]; 163 0 stevel break; 164 0 stevel 165 0 stevel default: 166 0 stevel n = 0; 167 0 stevel } 168 0 stevel 169 0 stevel return (MIN((ssize_t)n, size) / sizeof (long)); 170 0 stevel } 171 0 stevel 172 0 stevel int 173 0 stevel mdb_ia32_kvm_stack_iter(mdb_tgt_t *t, const mdb_tgt_gregset_t *gsp, 174 0 stevel mdb_tgt_stack_f *func, void *arg) 175 0 stevel { 176 0 stevel mdb_tgt_gregset_t gregs; 177 0 stevel kreg_t *kregs = &gregs.kregs[0]; 178 0 stevel int got_pc = (gsp->kregs[KREG_EIP] != 0); 179 0 stevel 180 0 stevel struct { 181 0 stevel uintptr_t fr_savfp; 182 0 stevel uintptr_t fr_savpc; 183 0 stevel long fr_argv[32]; 184 0 stevel } fr; 185 0 stevel 186 0 stevel uintptr_t fp = gsp->kregs[KREG_EBP]; 187 0 stevel uintptr_t pc = gsp->kregs[KREG_EIP]; 188 5084 johnlev uintptr_t lastfp; 189 0 stevel 190 0 stevel ssize_t size; 191 0 stevel uint_t argc; 192 5084 johnlev int detect_exception_frames = 0; 193 5084 johnlev #ifndef _KMDB 194 5084 johnlev int xp; 195 5084 johnlev 196 5084 johnlev if ((mdb_readsym(&xp, sizeof (xp), "xpv_panicking") != -1) && (xp > 0)) 197 5084 johnlev detect_exception_frames = 1; 198 5084 johnlev #endif 199 0 stevel 200 0 stevel bcopy(gsp, &gregs, sizeof (gregs)); 201 0 stevel 202 0 stevel while (fp != 0) { 203 0 stevel 204 0 stevel if (fp & (STACK_ALIGN - 1)) 205 0 stevel return (set_errno(EMDB_STKALIGN)); 206 0 stevel 207 0 stevel if ((size = mdb_tgt_vread(t, &fr, sizeof (fr), fp)) >= 208 0 stevel (ssize_t)(2 * sizeof (uintptr_t))) { 209 0 stevel size -= (ssize_t)(2 * sizeof (uintptr_t)); 210 0 stevel argc = kvm_argcount(t, fr.fr_savpc, size); 211 0 stevel } else { 212 0 stevel bzero(&fr, sizeof (fr)); 213 0 stevel argc = 0; 214 0 stevel } 215 0 stevel 216 0 stevel if (got_pc && func(arg, pc, argc, fr.fr_argv, &gregs) != 0) 217 0 stevel break; 218 0 stevel 219 0 stevel kregs[KREG_ESP] = kregs[KREG_EBP]; 220 0 stevel 221 5084 johnlev lastfp = fp; 222 5084 johnlev fp = fr.fr_savfp; 223 5084 johnlev /* 224 5084 johnlev * The Xen hypervisor marks a stack frame as belonging to 225 5084 johnlev * an exception by inverting the bits of the pointer to 226 5084 johnlev * that frame. We attempt to identify these frames by 227 5084 johnlev * inverting the pointer and seeing if it is within 0xfff 228 5084 johnlev * bytes of the last frame. 229 5084 johnlev */ 230 5084 johnlev if (detect_exception_frames) 231 5084 johnlev if ((fp != 0) && (fp < lastfp) && 232 5084 johnlev ((lastfp ^ ~fp) < 0xfff)) 233 5084 johnlev fp = ~fp; 234 5084 johnlev 235 5084 johnlev kregs[KREG_EBP] = fp; 236 0 stevel kregs[KREG_EIP] = pc = fr.fr_savpc; 237 0 stevel 238 0 stevel got_pc = (pc != 0); 239 0 stevel } 240 0 stevel 241 0 stevel return (0); 242 0 stevel } 243 0 stevel 244 0 stevel /* 245 0 stevel * Determine the return address for the current frame. Typically this is the 246 0 stevel * fr_savpc value from the current frame, but we also perform some special 247 0 stevel * handling to see if we are stopped on one of the first two instructions of a 248 0 stevel * typical function prologue, in which case %ebp will not be set up yet. 249 0 stevel */ 250 0 stevel int 251 0 stevel mdb_ia32_step_out(mdb_tgt_t *t, uintptr_t *p, kreg_t pc, kreg_t fp, kreg_t sp, 252 0 stevel mdb_instr_t curinstr) 253 0 stevel { 254 0 stevel struct frame fr; 255 0 stevel GElf_Sym s; 256 0 stevel char buf[1]; 257 0 stevel 258 0 stevel enum { 259 0 stevel M_PUSHL_EBP = 0x55, /* pushl %ebp */ 260 0 stevel M_MOVL_EBP = 0x8b /* movl %esp, %ebp */ 261 0 stevel }; 262 0 stevel 263 0 stevel if (mdb_tgt_lookup_by_addr(t, pc, MDB_TGT_SYM_FUZZY, 264 0 stevel buf, 0, &s, NULL) == 0) { 265 0 stevel if (pc == s.st_value && curinstr == M_PUSHL_EBP) 266 0 stevel fp = sp - 4; 267 0 stevel else if (pc == s.st_value + 1 && curinstr == M_MOVL_EBP) 268 0 stevel fp = sp; 269 0 stevel } 270 0 stevel 271 0 stevel if (mdb_tgt_vread(t, &fr, sizeof (fr), fp) == sizeof (fr)) { 272 0 stevel *p = fr.fr_savpc; 273 0 stevel return (0); 274 0 stevel } 275 0 stevel 276 0 stevel return (-1); /* errno is set for us */ 277 0 stevel } 278 0 stevel 279 0 stevel /* 280 0 stevel * Return the address of the next instruction following a call, or return -1 281 0 stevel * and set errno to EAGAIN if the target should just single-step. We perform 282 0 stevel * a bit of disassembly on the current instruction in order to determine if it 283 0 stevel * is a call and how many bytes should be skipped, depending on the exact form 284 0 stevel * of the call instruction that is being used. 285 0 stevel */ 286 0 stevel int 287 0 stevel mdb_ia32_next(mdb_tgt_t *t, uintptr_t *p, kreg_t pc, mdb_instr_t curinstr) 288 0 stevel { 289 0 stevel uint8_t m; 290 0 stevel 291 0 stevel enum { 292 0 stevel M_CALL_REL = 0xe8, /* call near with relative displacement */ 293 0 stevel M_CALL_REG = 0xff, /* call near indirect or call far register */ 294 0 stevel 295 0 stevel M_MODRM_MD = 0xc0, /* mask for Mod/RM byte Mod field */ 296 0 stevel M_MODRM_OP = 0x38, /* mask for Mod/RM byte opcode field */ 297 0 stevel M_MODRM_RM = 0x07, /* mask for Mod/RM byte R/M field */ 298 0 stevel 299 0 stevel M_MD_IND = 0x00, /* Mod code for [REG] */ 300 0 stevel M_MD_DSP8 = 0x40, /* Mod code for disp8[REG] */ 301 0 stevel M_MD_DSP32 = 0x80, /* Mod code for disp32[REG] */ 302 0 stevel M_MD_REG = 0xc0, /* Mod code for REG */ 303 0 stevel 304 0 stevel M_OP_IND = 0x10, /* Opcode for call near indirect */ 305 0 stevel M_RM_DSP32 = 0x05 /* R/M code for disp32 */ 306 0 stevel }; 307 0 stevel 308 0 stevel /* 309 0 stevel * If the opcode is a near call with relative displacement, assume the 310 0 stevel * displacement is a rel32 from the next instruction. 311 0 stevel */ 312 0 stevel if (curinstr == M_CALL_REL) { 313 0 stevel *p = pc + sizeof (mdb_instr_t) + sizeof (uint32_t); 314 0 stevel return (0); 315 0 stevel } 316 0 stevel 317 0 stevel /* 318 0 stevel * If the opcode is a call near indirect or call far register opcode, 319 0 stevel * read the subsequent Mod/RM byte to perform additional decoding. 320 0 stevel */ 321 0 stevel if (curinstr == M_CALL_REG) { 322 0 stevel if (mdb_tgt_vread(t, &m, sizeof (m), pc + 1) != sizeof (m)) 323 0 stevel return (-1); /* errno is set for us */ 324 0 stevel 325 0 stevel /* 326 0 stevel * If the Mod/RM opcode extension indicates a near indirect 327 0 stevel * call, then skip the appropriate number of additional 328 0 stevel * bytes depending on the addressing form that is used. 329 0 stevel */ 330 0 stevel if ((m & M_MODRM_OP) == M_OP_IND) { 331 0 stevel switch (m & M_MODRM_MD) { 332 0 stevel case M_MD_DSP8: 333 0 stevel *p = pc + 3; /* skip pr_instr, m, disp8 */ 334 0 stevel break; 335 0 stevel case M_MD_DSP32: 336 0 stevel *p = pc + 6; /* skip pr_instr, m, disp32 */ 337 0 stevel break; 338 0 stevel case M_MD_IND: 339 0 stevel if ((m & M_MODRM_RM) == M_RM_DSP32) { 340 0 stevel *p = pc + 6; 341 0 stevel break; /* skip pr_instr, m, disp32 */ 342 0 stevel } 343 0 stevel /* FALLTHRU */ 344 0 stevel case M_MD_REG: 345 0 stevel *p = pc + 2; /* skip pr_instr, m */ 346 0 stevel break; 347 0 stevel } 348 0 stevel return (0); 349 0 stevel } 350 0 stevel } 351 0 stevel 352 0 stevel return (set_errno(EAGAIN)); 353 0 stevel } 354 0 stevel 355 0 stevel /*ARGSUSED*/ 356 0 stevel int 357 0 stevel mdb_ia32_kvm_frame(void *arglim, uintptr_t pc, uint_t argc, const long *argv, 358 0 stevel const mdb_tgt_gregset_t *gregs) 359 0 stevel { 360 0 stevel argc = MIN(argc, (uint_t)arglim); 361 0 stevel mdb_printf("%a(", pc); 362 0 stevel 363 0 stevel if (argc != 0) { 364 0 stevel mdb_printf("%lr", *argv++); 365 0 stevel for (argc--; argc != 0; argc--) 366 0 stevel mdb_printf(", %lr", *argv++); 367 0 stevel } 368 0 stevel 369 0 stevel mdb_printf(")\n"); 370 0 stevel return (0); 371 0 stevel } 372 0 stevel 373 0 stevel int 374 0 stevel mdb_ia32_kvm_framev(void *arglim, uintptr_t pc, uint_t argc, const long *argv, 375 0 stevel const mdb_tgt_gregset_t *gregs) 376 0 stevel { 377 0 stevel argc = MIN(argc, (uint_t)arglim); 378 0 stevel mdb_printf("%0?lr %a(", gregs->kregs[KREG_EBP], pc); 379 0 stevel 380 0 stevel if (argc != 0) { 381 0 stevel mdb_printf("%lr", *argv++); 382 0 stevel for (argc--; argc != 0; argc--) 383 0 stevel mdb_printf(", %lr", *argv++); 384 0 stevel } 385 0 stevel 386 0 stevel mdb_printf(")\n"); 387 0 stevel return (0); 388 0 stevel } 389
Indexes created Thu Nov 26 20:23:21 UTC 2009
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