1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 /* 22 * Copyright 2008 Sun Microsystems, Inc. All rights reserved. 23 * Use is subject to license terms. 24 * 25 * Copyright 2018 Joyent, Inc. 26 * Copyright 2024 Oxide Computer Company 27 */ 28 29 /* 30 * Libkvm Kernel Target Intel 32-bit component 31 * 32 * This file provides the ISA-dependent portion of the libkvm kernel target. 33 * For more details on the implementation refer to mdb_kvm.c. 34 */ 35 36 #include <sys/types.h> 37 #include <sys/regset.h> 38 #include <sys/frame.h> 39 #include <sys/stack.h> 40 #include <sys/sysmacros.h> 41 #include <sys/panic.h> 42 #include <strings.h> 43 44 #include <mdb/mdb_target_impl.h> 45 #include <mdb/mdb_disasm.h> 46 #include <mdb/mdb_modapi.h> 47 #include <mdb/mdb_conf.h> 48 #include <mdb/mdb_kreg_impl.h> 49 #include <mdb/mdb_isautil.h> 50 #include <mdb/mdb_ia32util.h> 51 #include <mdb/kvm_isadep.h> 52 #include <mdb/mdb_kvm.h> 53 #include <mdb/mdb_err.h> 54 #include <mdb/mdb_debug.h> 55 #include <mdb/mdb.h> 56 57 58 /*ARGSUSED*/ 59 int 60 kt_regs(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv) 61 { 62 mdb_ia32_printregs((const mdb_tgt_gregset_t *)addr); 63 return (DCMD_OK); 64 } 65 66 static int 67 kt_stack_common(uintptr_t addr, uint_t flags, int argc, 68 const mdb_arg_t *argv, mdb_tgt_stack_f *func) 69 { 70 kt_data_t *kt = mdb.m_target->t_data; 71 void *arg = (void *)mdb.m_nargs; 72 mdb_tgt_gregset_t gregs, *grp; 73 74 if (flags & DCMD_ADDRSPEC) { 75 bzero(&gregs, sizeof (gregs)); 76 gregs.kregs[KREG_EBP] = addr; 77 grp = &gregs; 78 } else 79 grp = kt->k_regs; 80 81 if (argc != 0) { 82 if (argv->a_type == MDB_TYPE_CHAR || argc > 1) 83 return (DCMD_USAGE); 84 85 if (argv->a_type == MDB_TYPE_STRING) 86 arg = (void *)(uint_t)mdb_strtoull(argv->a_un.a_str); 87 else 88 arg = (void *)(uint_t)argv->a_un.a_val; 89 } 90 91 (void) mdb_ia32_kvm_stack_iter(mdb.m_target, grp, func, arg); 92 return (DCMD_OK); 93 } 94 95 int 96 kt_stack(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv) 97 { 98 return (kt_stack_common(addr, flags, argc, argv, mdb_ia32_kvm_frame)); 99 } 100 101 int 102 kt_stackv(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv) 103 { 104 return (kt_stack_common(addr, flags, argc, argv, mdb_ia32_kvm_framev)); 105 } 106 107 const mdb_tgt_ops_t kt_ia32_ops = { 108 kt_setflags, /* t_setflags */ 109 kt_setcontext, /* t_setcontext */ 110 kt_activate, /* t_activate */ 111 kt_deactivate, /* t_deactivate */ 112 (void (*)())(uintptr_t)mdb_tgt_nop, /* t_periodic */ 113 kt_destroy, /* t_destroy */ 114 kt_name, /* t_name */ 115 (const char *(*)())mdb_conf_isa, /* t_isa */ 116 kt_platform, /* t_platform */ 117 kt_uname, /* t_uname */ 118 kt_dmodel, /* t_dmodel */ 119 kt_aread, /* t_aread */ 120 kt_awrite, /* t_awrite */ 121 kt_vread, /* t_vread */ 122 kt_vwrite, /* t_vwrite */ 123 kt_pread, /* t_pread */ 124 kt_pwrite, /* t_pwrite */ 125 kt_fread, /* t_fread */ 126 kt_fwrite, /* t_fwrite */ 127 (ssize_t (*)())mdb_tgt_notsup, /* t_ioread */ 128 (ssize_t (*)())mdb_tgt_notsup, /* t_iowrite */ 129 kt_vtop, /* t_vtop */ 130 kt_lookup_by_name, /* t_lookup_by_name */ 131 kt_lookup_by_addr, /* t_lookup_by_addr */ 132 kt_symbol_iter, /* t_symbol_iter */ 133 kt_mapping_iter, /* t_mapping_iter */ 134 kt_object_iter, /* t_object_iter */ 135 kt_addr_to_map, /* t_addr_to_map */ 136 kt_name_to_map, /* t_name_to_map */ 137 kt_addr_to_ctf, /* t_addr_to_ctf */ 138 kt_name_to_ctf, /* t_name_to_ctf */ 139 kt_status, /* t_status */ 140 (int (*)())mdb_tgt_notsup, /* t_run */ 141 (int (*)())mdb_tgt_notsup, /* t_step */ 142 (int (*)())mdb_tgt_notsup, /* t_step_out */ 143 (int (*)())mdb_tgt_notsup, /* t_next */ 144 (int (*)())mdb_tgt_notsup, /* t_cont */ 145 (int (*)())mdb_tgt_notsup, /* t_signal */ 146 (int (*)())(uintptr_t)mdb_tgt_null, /* t_add_vbrkpt */ 147 (int (*)())(uintptr_t)mdb_tgt_null, /* t_add_sbrkpt */ 148 (int (*)())(uintptr_t)mdb_tgt_null, /* t_add_pwapt */ 149 (int (*)())(uintptr_t)mdb_tgt_null, /* t_add_vwapt */ 150 (int (*)())(uintptr_t)mdb_tgt_null, /* t_add_iowapt */ 151 (int (*)())(uintptr_t)mdb_tgt_null, /* t_add_sysenter */ 152 (int (*)())(uintptr_t)mdb_tgt_null, /* t_add_sysexit */ 153 (int (*)())(uintptr_t)mdb_tgt_null, /* t_add_signal */ 154 (int (*)())(uintptr_t)mdb_tgt_null, /* t_add_fault */ 155 kt_getareg, /* t_getareg */ 156 kt_putareg, /* t_putareg */ 157 mdb_ia32_kvm_stack_iter, /* t_stack_iter */ 158 (int (*)())mdb_tgt_notsup, /* t_auxv */ 159 (int (*)())(uintptr_t)mdb_tgt_notsup /* t_thread_name */ 160 }; 161 162 void 163 kt_regs_to_kregs(struct regs *regs, mdb_tgt_gregset_t *gregs) 164 { 165 gregs->kregs[KREG_SAVFP] = regs->r_savfp; 166 gregs->kregs[KREG_SAVPC] = regs->r_savpc; 167 gregs->kregs[KREG_EAX] = regs->r_eax; 168 gregs->kregs[KREG_EBX] = regs->r_ebx; 169 gregs->kregs[KREG_ECX] = regs->r_ecx; 170 gregs->kregs[KREG_EDX] = regs->r_edx; 171 gregs->kregs[KREG_ESI] = regs->r_esi; 172 gregs->kregs[KREG_EDI] = regs->r_edi; 173 gregs->kregs[KREG_EBP] = regs->r_ebp; 174 gregs->kregs[KREG_ESP] = regs->r_esp; 175 gregs->kregs[KREG_CS] = regs->r_cs; 176 gregs->kregs[KREG_DS] = regs->r_ds; 177 gregs->kregs[KREG_SS] = regs->r_ss; 178 gregs->kregs[KREG_ES] = regs->r_es; 179 gregs->kregs[KREG_FS] = regs->r_fs; 180 gregs->kregs[KREG_GS] = regs->r_gs; 181 gregs->kregs[KREG_EFLAGS] = regs->r_efl; 182 gregs->kregs[KREG_EIP] = regs->r_eip; 183 gregs->kregs[KREG_UESP] = regs->r_uesp; 184 gregs->kregs[KREG_TRAPNO] = regs->r_trapno; 185 gregs->kregs[KREG_ERR] = regs->r_err; 186 } 187 188 void 189 kt_ia32_init(mdb_tgt_t *t) 190 { 191 kt_data_t *kt = t->t_data; 192 panic_data_t pd; 193 label_t label; 194 struct regs regs; 195 kreg_t *kregs; 196 uintptr_t addr; 197 198 /* 199 * Initialize the machine-dependent parts of the kernel target 200 * structure. Once this is complete and we fill in the ops 201 * vector, the target is now fully constructed and we can use 202 * the target API itself to perform the rest of our initialization. 203 */ 204 kt->k_rds = mdb_ia32_kregs; 205 kt->k_regs = mdb_zalloc(sizeof (mdb_tgt_gregset_t), UM_SLEEP); 206 kt->k_regsize = sizeof (mdb_tgt_gregset_t); 207 kt->k_dcmd_regs = kt_regs; 208 kt->k_dcmd_stack = kt_stack; 209 kt->k_dcmd_stackv = kt_stackv; 210 kt->k_dcmd_stackr = kt_stackv; 211 kt->k_dcmd_cpustack = kt_cpustack; 212 kt->k_dcmd_cpuregs = kt_cpuregs; 213 214 t->t_ops = &kt_ia32_ops; 215 kregs = kt->k_regs->kregs; 216 217 (void) mdb_dis_select("ia32"); 218 219 /* 220 * Lookup the symbols corresponding to subroutines in locore.s where 221 * we expect a saved regs structure to be pushed on the stack. When 222 * performing stack tracebacks we will attempt to detect interrupt 223 * frames by comparing the %eip value to these symbols. 224 */ 225 (void) mdb_tgt_lookup_by_name(t, MDB_TGT_OBJ_EXEC, 226 "cmnint", &kt->k_intr_sym, NULL); 227 228 (void) mdb_tgt_lookup_by_name(t, MDB_TGT_OBJ_EXEC, 229 "cmntrap", &kt->k_trap_sym, NULL); 230 231 /* 232 * Don't attempt to load any thread or register information if 233 * we're examining the live operating system. 234 */ 235 if (kt->k_symfile != NULL && strcmp(kt->k_symfile, "/dev/ksyms") == 0) 236 return; 237 238 /* 239 * If the panicbuf symbol is present and we can consume a panicbuf 240 * header of the appropriate version from this address, then we can 241 * initialize our current register set based on its contents. 242 * Prior to the re-structuring of panicbuf, our only register data 243 * was the panic_regs label_t, into which a setjmp() was performed, 244 * or the panic_reg register pointer, which was only non-zero if 245 * the system panicked as a result of a trap calling die(). 246 */ 247 if (mdb_tgt_readsym(t, MDB_TGT_AS_VIRT, &pd, sizeof (pd), 248 MDB_TGT_OBJ_EXEC, "panicbuf") == sizeof (pd) && 249 pd.pd_version == PANICBUFVERS) { 250 251 size_t pd_size = MIN(PANICBUFSIZE, pd.pd_msgoff); 252 panic_data_t *pdp = mdb_zalloc(pd_size, UM_SLEEP); 253 uint_t i, n; 254 255 (void) mdb_tgt_readsym(t, MDB_TGT_AS_VIRT, pdp, pd_size, 256 MDB_TGT_OBJ_EXEC, "panicbuf"); 257 258 n = (pd_size - (sizeof (panic_data_t) - 259 sizeof (panic_nv_t))) / sizeof (panic_nv_t); 260 261 for (i = 0; i < n; i++) { 262 (void) kt_putareg(t, kt->k_tid, 263 pdp->pd_nvdata[i].pnv_name, 264 pdp->pd_nvdata[i].pnv_value); 265 } 266 267 mdb_free(pdp, pd_size); 268 269 return; 270 } 271 272 if (mdb_tgt_readsym(t, MDB_TGT_AS_VIRT, &addr, sizeof (addr), 273 MDB_TGT_OBJ_EXEC, "panic_reg") == sizeof (addr) && addr != 0 && 274 mdb_tgt_vread(t, ®s, sizeof (regs), addr) == sizeof (regs)) { 275 kt_regs_to_kregs(®s, kt->k_regs); 276 return; 277 } 278 279 /* 280 * If we can't read any panic regs, then our penultimate try is for any 281 * CPU context that may have been stored (for example, in Xen core 282 * dumps). As this can only succeed for kernels with the above 283 * methods available, we let it over-ride the older panic_regs method, 284 * which will always manage to read the label_t, even if there's 285 * nothing useful there. 286 */ 287 if (kt_kvmregs(t, 0, kt->k_regs) == 0) 288 return; 289 290 if (mdb_tgt_readsym(t, MDB_TGT_AS_VIRT, &label, sizeof (label), 291 MDB_TGT_OBJ_EXEC, "panic_regs") == sizeof (label)) { 292 kregs[KREG_EDI] = label.val[0]; 293 kregs[KREG_ESI] = label.val[1]; 294 kregs[KREG_EBX] = label.val[2]; 295 kregs[KREG_EBP] = label.val[3]; 296 kregs[KREG_ESP] = label.val[4]; 297 kregs[KREG_EIP] = label.val[5]; 298 return; 299 } 300 301 warn("failed to read panicbuf, panic_reg and panic_regs -- " 302 "current register set will be unavailable\n"); 303 } 304