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