/* * CDDL HEADER START * * The contents of this file are subject to the terms of the * Common Development and Distribution License (the "License"). * You may not use this file except in compliance with the License. * * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE * or http://www.opensolaris.org/os/licensing. * See the License for the specific language governing permissions * and limitations under the License. * * When distributing Covered Code, include this CDDL HEADER in each * file and include the License file at usr/src/OPENSOLARIS.LICENSE. * If applicable, add the following below this CDDL HEADER, with the * fields enclosed by brackets "[]" replaced with your own identifying * information: Portions Copyright [yyyy] [name of copyright owner] * * CDDL HEADER END */ /* * Copyright (c) 1999, 2010, Oracle and/or its affiliates. All rights reserved. */ /* * Copyright 2019 Joyent, Inc. */ /* * Libkvm Kernel Target * * The libkvm kernel target provides access to both crash dumps and live * kernels through /dev/ksyms and /dev/kmem, using the facilities provided by * the libkvm.so library. The target-specific data structures are shared * between this file (common code) and the ISA-dependent parts of the target, * and so they are defined in the mdb_kvm.h header. The target processes an * "executable" (/dev/ksyms or the unix.X file) which contains a primary * .symtab and .dynsym, and then also iterates over the krtld module chain in * the kernel in order to obtain a list of loaded modules and per-module symbol * tables. To improve startup performance, the per-module symbol tables are * instantiated on-the-fly whenever an address lookup falls within the text * section of a given module. The target also relies on services from the * mdb_ks (kernel support) module, which contains pieces of the implementation * that must be compiled against the kernel implementation. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define KT_RELOC_BUF(buf, obase, nbase) \ ((uintptr_t)(buf) - (uintptr_t)(obase) + (uintptr_t)(nbase)) #define KT_BAD_BUF(buf, base, size) \ ((uintptr_t)(buf) < (uintptr_t)(base) || \ ((uintptr_t)(buf) >= (uintptr_t)(base) + (uintptr_t)(size))) typedef struct kt_symarg { mdb_tgt_sym_f *sym_cb; /* Caller's callback function */ void *sym_data; /* Callback function argument */ uint_t sym_type; /* Symbol type/binding filter */ mdb_syminfo_t sym_info; /* Symbol id and table id */ const char *sym_obj; /* Containing object */ } kt_symarg_t; typedef struct kt_maparg { mdb_tgt_t *map_target; /* Target used for mapping iter */ mdb_tgt_map_f *map_cb; /* Caller's callback function */ void *map_data; /* Callback function argument */ } kt_maparg_t; static const char KT_MODULE[] = "mdb_ks"; static const char KT_CTFPARENT[] = "genunix"; static void (*print_buildversion)(void); static void kt_load_module(kt_data_t *kt, mdb_tgt_t *t, kt_module_t *km) { km->km_data = mdb_alloc(km->km_datasz, UM_SLEEP); (void) mdb_tgt_vread(t, km->km_data, km->km_datasz, km->km_symspace_va); km->km_symbuf = (void *) KT_RELOC_BUF(km->km_symtab_va, km->km_symspace_va, km->km_data); km->km_strtab = (char *) KT_RELOC_BUF(km->km_strtab_va, km->km_symspace_va, km->km_data); km->km_symtab = mdb_gelf_symtab_create_raw(&kt->k_file->gf_ehdr, &km->km_symtab_hdr, km->km_symbuf, &km->km_strtab_hdr, km->km_strtab, MDB_TGT_SYMTAB); } static void kt_load_modules(kt_data_t *kt, mdb_tgt_t *t) { char name[MAXNAMELEN]; uintptr_t addr, head; struct module kmod; struct modctl ctl; Shdr symhdr, strhdr; GElf_Sym sym; kt_module_t *km; if (mdb_tgt_lookup_by_name(t, MDB_TGT_OBJ_EXEC, "modules", &sym, NULL) == -1) { warn("failed to get 'modules' symbol"); return; } if (mdb_tgt_readsym(t, MDB_TGT_AS_VIRT, &ctl, sizeof (ctl), MDB_TGT_OBJ_EXEC, "modules") != sizeof (ctl)) { warn("failed to read 'modules' struct"); return; } addr = head = (uintptr_t)sym.st_value; do { if (addr == 0) break; /* Avoid spurious NULL pointers in list */ if (mdb_tgt_vread(t, &ctl, sizeof (ctl), addr) == -1) { warn("failed to read modctl at %p", (void *)addr); return; } if (ctl.mod_mp == NULL) continue; /* No associated krtld structure */ if (mdb_tgt_readstr(t, MDB_TGT_AS_VIRT, name, MAXNAMELEN, (uintptr_t)ctl.mod_modname) <= 0) { warn("failed to read module name at %p", (void *)ctl.mod_modname); continue; } mdb_dprintf(MDB_DBG_KMOD, "reading mod %s (%p)\n", name, (void *)addr); if (mdb_nv_lookup(&kt->k_modules, name) != NULL) { warn("skipping duplicate module '%s', id=%d\n", name, ctl.mod_id); continue; } if (mdb_tgt_vread(t, &kmod, sizeof (kmod), (uintptr_t)ctl.mod_mp) == -1) { warn("failed to read module at %p\n", (void *)ctl.mod_mp); continue; } if (kmod.symspace == NULL || kmod.symhdr == NULL || kmod.strhdr == NULL) { /* * If no buffer for the symbols has been allocated, * or the shdrs for .symtab and .strtab are missing, * then we're out of luck. */ continue; } if (mdb_tgt_vread(t, &symhdr, sizeof (Shdr), (uintptr_t)kmod.symhdr) == -1) { warn("failed to read .symtab header for '%s', id=%d", name, ctl.mod_id); continue; } if (mdb_tgt_vread(t, &strhdr, sizeof (Shdr), (uintptr_t)kmod.strhdr) == -1) { warn("failed to read .strtab header for '%s', id=%d", name, ctl.mod_id); continue; } /* * Now get clever: f(*^ing krtld didn't used to bother updating * its own kmod.symsize value. We know that prior to this bug * being fixed, symspace was a contiguous buffer containing * .symtab, .strtab, and the symbol hash table in that order. * So if symsize is zero, recompute it as the size of .symtab * plus the size of .strtab. We don't need to load the hash * table anyway since we re-hash all the symbols internally. */ if (kmod.symsize == 0) kmod.symsize = symhdr.sh_size + strhdr.sh_size; /* * Similar logic can be used to make educated guesses * at the values of kmod.symtbl and kmod.strings. */ if (kmod.symtbl == NULL) kmod.symtbl = kmod.symspace; if (kmod.strings == NULL) kmod.strings = kmod.symspace + symhdr.sh_size; /* * Make sure things seem reasonable before we proceed * to actually read and decipher the symspace. */ if (KT_BAD_BUF(kmod.symtbl, kmod.symspace, kmod.symsize) || KT_BAD_BUF(kmod.strings, kmod.symspace, kmod.symsize)) { warn("skipping module '%s', id=%d (corrupt symspace)\n", name, ctl.mod_id); continue; } km = mdb_zalloc(sizeof (kt_module_t), UM_SLEEP); km->km_name = strdup(name); (void) mdb_nv_insert(&kt->k_modules, km->km_name, NULL, (uintptr_t)km, MDB_NV_EXTNAME); km->km_datasz = kmod.symsize; km->km_symspace_va = (uintptr_t)kmod.symspace; km->km_symtab_va = (uintptr_t)kmod.symtbl; km->km_strtab_va = (uintptr_t)kmod.strings; km->km_symtab_hdr = symhdr; km->km_strtab_hdr = strhdr; km->km_text_va = (uintptr_t)kmod.text; km->km_text_size = kmod.text_size; km->km_data_va = (uintptr_t)kmod.data; km->km_data_size = kmod.data_size; km->km_bss_va = (uintptr_t)kmod.bss; km->km_bss_size = kmod.bss_size; if (kt->k_ctfvalid) { km->km_ctf_va = (uintptr_t)kmod.ctfdata; km->km_ctf_size = kmod.ctfsize; } /* * Add the module to the end of the list of modules in load- * dependency order. This is needed to load the corresponding * debugger modules in the same order for layering purposes. */ mdb_list_append(&kt->k_modlist, km); if (t->t_flags & MDB_TGT_F_PRELOAD) { mdb_iob_printf(mdb.m_out, " %s", name); mdb_iob_flush(mdb.m_out); kt_load_module(kt, t, km); } } while ((addr = (uintptr_t)ctl.mod_next) != head); } int kt_setflags(mdb_tgt_t *t, int flags) { int iochg = ((flags ^ t->t_flags) & MDB_TGT_F_ALLOWIO) && !mdb_prop_postmortem; int rwchg = (flags ^ t->t_flags) & MDB_TGT_F_RDWR; kt_data_t *kt = t->t_data; const char *kvmfile; void *cookie; int mode; if (!iochg && !rwchg) return (0); if (kt->k_xpv_domu) { warn("read-only target"); return (-1); } if (iochg) { kvmfile = (flags & MDB_TGT_F_ALLOWIO) ? "/dev/allkmem" : "/dev/kmem"; } else { kvmfile = kt->k_kvmfile; } mode = (flags & MDB_TGT_F_RDWR) ? O_RDWR : O_RDONLY; if ((cookie = kt->k_kb_ops->kb_open(kt->k_symfile, kvmfile, NULL, mode, mdb.m_pname)) == NULL) { /* We failed to re-open, so don't change t_flags */ warn("failed to re-open target"); return (-1); } /* * We successfully reopened the target, so update k_kvmfile. Also set * the RDWR and ALLOWIO bits in t_flags to match those in flags. */ (void) kt->k_kb_ops->kb_close(kt->k_cookie); kt->k_cookie = cookie; if (kvmfile != kt->k_kvmfile) { strfree(kt->k_kvmfile); kt->k_kvmfile = strdup(kvmfile); } t->t_flags = (t->t_flags & ~(MDB_TGT_F_RDWR | MDB_TGT_F_ALLOWIO)) | (flags & (MDB_TGT_F_RDWR | MDB_TGT_F_ALLOWIO)); return (0); } /* * Determine which PIDs (if any) have their pages saved in the dump. We * do this by looking for content flags in dump_flags in the header. These * flags, which won't be set in older dumps, tell us whether a single process * has had its pages included in the dump. If a single process has been * included, we need to get the PID for that process from the dump_pids * array in the dump. */ static int kt_find_dump_contents(kt_data_t *kt) { dumphdr_t *dh = kt->k_dumphdr; pid_t pid = -1; if (dh->dump_flags & DF_ALL) return (KT_DUMPCONTENT_ALL); if (dh->dump_flags & DF_CURPROC) { if ((pid = kt->k_dump_find_curproc()) == -1) return (KT_DUMPCONTENT_INVALID); else return (pid); } else { return (KT_DUMPCONTENT_KERNEL); } } static int kt_dump_contains_proc(mdb_tgt_t *t, void *context) { kt_data_t *kt = t->t_data; pid_t (*f_pid)(uintptr_t); pid_t reqpid; switch (kt->k_dumpcontent) { case KT_DUMPCONTENT_KERNEL: return (0); case KT_DUMPCONTENT_ALL: return (1); case KT_DUMPCONTENT_INVALID: goto procnotfound; default: f_pid = (pid_t (*)()) dlsym(RTLD_NEXT, "mdb_kproc_pid"); if (f_pid == NULL) goto procnotfound; reqpid = f_pid((uintptr_t)context); if (reqpid == -1) goto procnotfound; return (kt->k_dumpcontent == reqpid); } procnotfound: warn("unable to determine whether dump contains proc %p\n", context); return (1); } int kt_setcontext(mdb_tgt_t *t, void *context) { if (context != NULL) { const char *argv[2]; int argc = 0; mdb_tgt_t *ct; kt_data_t *kt = t->t_data; argv[argc++] = (const char *)context; argv[argc] = NULL; if (kt->k_dumphdr != NULL && !kt_dump_contains_proc(t, context)) { warn("dump does not contain pages for proc %p\n", context); return (-1); } if ((ct = mdb_tgt_create(mdb_kproc_tgt_create, t->t_flags, argc, argv)) == NULL) return (-1); mdb_printf("debugger context set to proc %p\n", context); mdb_tgt_activate(ct); } else mdb_printf("debugger context set to kernel\n"); return (0); } static int kt_stack(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv) { kt_data_t *kt = mdb.m_target->t_data; return (kt->k_dcmd_stack(addr, flags, argc, argv)); } static int kt_stackv(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv) { kt_data_t *kt = mdb.m_target->t_data; return (kt->k_dcmd_stackv(addr, flags, argc, argv)); } static int kt_stackr(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv) { kt_data_t *kt = mdb.m_target->t_data; return (kt->k_dcmd_stackr(addr, flags, argc, argv)); } static int kt_regs(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv) { kt_data_t *kt = mdb.m_target->t_data; if (argc != 0 || (flags & DCMD_ADDRSPEC)) return (DCMD_USAGE); addr = (uintptr_t)kt->k_regs; return (kt->k_dcmd_regs(addr, flags, argc, argv)); } #ifdef __x86 static int kt_cpustack(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv) { kt_data_t *kt = mdb.m_target->t_data; return (kt->k_dcmd_cpustack(addr, flags, argc, argv)); } static int kt_cpuregs(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv) { kt_data_t *kt = mdb.m_target->t_data; return (kt->k_dcmd_cpuregs(addr, flags, argc, argv)); } #endif /* __x86 */ /*ARGSUSED*/ static int kt_status_dcmd(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv) { kt_data_t *kt = mdb.m_target->t_data; struct utsname uts; bzero(&uts, sizeof (uts)); (void) strcpy(uts.nodename, "unknown machine"); (void) kt_uname(mdb.m_target, &uts); if (mdb_prop_postmortem) { mdb_printf("debugging %scrash dump %s (%d-bit) from %s\n", kt->k_xpv_domu ? "domain " : "", kt->k_kvmfile, (int)(sizeof (void *) * NBBY), uts.nodename); } else { mdb_printf("debugging live kernel (%d-bit) on %s\n", (int)(sizeof (void *) * NBBY), uts.nodename); } mdb_printf("operating system: %s %s (%s)\n", uts.release, uts.version, uts.machine); if (print_buildversion != NULL) print_buildversion(); if (kt->k_dumphdr) { dumphdr_t *dh = kt->k_dumphdr; mdb_printf("image uuid: %s\n", dh->dump_uuid[0] != '\0' ? dh->dump_uuid : "(not set)"); mdb_printf("panic message: %s\n", dh->dump_panicstring); kt->k_dump_print_content(dh, kt->k_dumpcontent); } else { char uuid[UUID_PRINTABLE_STRING_LENGTH]; if (mdb_readsym(uuid, sizeof (uuid), "dump_osimage_uuid") == sizeof (uuid) && uuid[sizeof (uuid) - 1] == '\0') { mdb_printf("image uuid: %s\n", uuid[0] != '\0' ? uuid : "(not set)"); } } return (DCMD_OK); } static const mdb_dcmd_t kt_dcmds[] = { { "$c", "?[cnt]", "print stack backtrace", kt_stack }, { "$C", "?[cnt]", "print stack backtrace", kt_stackv }, { "$r", NULL, "print general-purpose registers", kt_regs }, { "$?", NULL, "print status and registers", kt_regs }, { "regs", NULL, "print general-purpose registers", kt_regs }, { "stack", "?[cnt]", "print stack backtrace", kt_stack }, { "stackregs", "?", "print stack backtrace and registers", kt_stackr }, #ifdef __x86 { "cpustack", "?[-v] [-c cpuid] [cnt]", "print stack backtrace for a " "specific CPU", kt_cpustack }, { "cpuregs", "?[-c cpuid]", "print general-purpose registers for a " "specific CPU", kt_cpuregs }, #endif { "status", NULL, "print summary of current target", kt_status_dcmd }, { NULL } }; static uintmax_t reg_disc_get(const mdb_var_t *v) { mdb_tgt_t *t = MDB_NV_COOKIE(v); kt_data_t *kt = t->t_data; mdb_tgt_reg_t r = 0; (void) mdb_tgt_getareg(t, kt->k_tid, mdb_nv_get_name(v), &r); return (r); } static kt_module_t * kt_module_by_name(kt_data_t *kt, const char *name) { kt_module_t *km; for (km = mdb_list_next(&kt->k_modlist); km; km = mdb_list_next(km)) { if (strcmp(name, km->km_name) == 0) return (km); } return (NULL); } void kt_activate(mdb_tgt_t *t) { static const mdb_nv_disc_t reg_disc = { NULL, reg_disc_get }; kt_data_t *kt = t->t_data; void *sym; int oflag = 0; mdb_prop_postmortem = kt->k_xpv_domu || (kt->k_dumphdr != NULL); mdb_prop_kernel = TRUE; mdb_prop_datamodel = MDB_TGT_MODEL_NATIVE; if (kt->k_activated == FALSE) { struct utsname u1, u2; /* * If we're examining a crash dump, root is /, and uname(2) * does not match the utsname in the dump, issue a warning. * Note that we are assuming that the modules and macros in * /usr/lib are compiled against the kernel from uname -rv. */ if (mdb_prop_postmortem && strcmp(mdb.m_root, "/") == 0 && uname(&u1) >= 0 && kt_uname(t, &u2) >= 0 && (strcmp(u1.release, u2.release) || strcmp(u1.version, u2.version))) { mdb_warn("warning: dump is from %s %s %s; dcmds and " "macros may not match kernel implementation\n", u2.sysname, u2.release, u2.version); } if (mdb_module_load(KT_MODULE, MDB_MOD_GLOBAL) < 0) { warn("failed to load kernel support module -- " "some modules may not load\n"); } print_buildversion = (void (*)(void))dlsym(RTLD_NEXT, "mdb_print_buildversion"); if (mdb_prop_postmortem && kt->k_dumphdr != NULL) { sym = dlsym(RTLD_NEXT, "mdb_dump_print_content"); if (sym != NULL) kt->k_dump_print_content = (void (*)())sym; sym = dlsym(RTLD_NEXT, "mdb_dump_find_curproc"); if (sym != NULL) kt->k_dump_find_curproc = (int (*)())sym; kt->k_dumpcontent = kt_find_dump_contents(kt); } if (t->t_flags & MDB_TGT_F_PRELOAD) { oflag = mdb_iob_getflags(mdb.m_out) & MDB_IOB_PGENABLE; mdb_iob_clrflags(mdb.m_out, oflag); mdb_iob_puts(mdb.m_out, "Preloading module symbols: ["); mdb_iob_flush(mdb.m_out); } if (!(t->t_flags & MDB_TGT_F_NOLOAD)) { kt_load_modules(kt, t); /* * Determine where the CTF data for krtld is. If krtld * is rolled into unix, force load the MDB krtld * module. */ kt->k_rtld_name = "krtld"; if (kt_module_by_name(kt, "krtld") == NULL) { (void) mdb_module_load("krtld", MDB_MOD_SILENT); kt->k_rtld_name = "unix"; } } if (t->t_flags & MDB_TGT_F_PRELOAD) { mdb_iob_puts(mdb.m_out, " ]\n"); mdb_iob_setflags(mdb.m_out, oflag); } kt->k_activated = TRUE; } (void) mdb_tgt_register_dcmds(t, &kt_dcmds[0], MDB_MOD_FORCE); /* Export some of our registers as named variables */ mdb_tgt_register_regvars(t, kt->k_rds, ®_disc, MDB_NV_RDONLY); mdb_tgt_elf_export(kt->k_file); } void kt_deactivate(mdb_tgt_t *t) { kt_data_t *kt = t->t_data; const mdb_tgt_regdesc_t *rdp; const mdb_dcmd_t *dcp; for (rdp = kt->k_rds; rdp->rd_name != NULL; rdp++) { mdb_var_t *v; if (!(rdp->rd_flags & MDB_TGT_R_EXPORT)) continue; /* Didn't export register as a variable */ if ((v = mdb_nv_lookup(&mdb.m_nv, rdp->rd_name)) != NULL) { v->v_flags &= ~MDB_NV_PERSIST; mdb_nv_remove(&mdb.m_nv, v); } } for (dcp = &kt_dcmds[0]; dcp->dc_name != NULL; dcp++) { if (mdb_module_remove_dcmd(t->t_module, dcp->dc_name) == -1) warn("failed to remove dcmd %s", dcp->dc_name); } mdb_prop_postmortem = FALSE; mdb_prop_kernel = FALSE; mdb_prop_datamodel = MDB_TGT_MODEL_UNKNOWN; } /*ARGSUSED*/ const char * kt_name(mdb_tgt_t *t) { return ("kvm"); } const char * kt_platform(mdb_tgt_t *t) { kt_data_t *kt = t->t_data; return (kt->k_platform); } int kt_uname(mdb_tgt_t *t, struct utsname *utsp) { return (mdb_tgt_readsym(t, MDB_TGT_AS_VIRT, utsp, sizeof (struct utsname), MDB_TGT_OBJ_EXEC, "utsname")); } /*ARGSUSED*/ int kt_dmodel(mdb_tgt_t *t) { return (MDB_TGT_MODEL_NATIVE); } ssize_t kt_aread(mdb_tgt_t *t, mdb_tgt_as_t as, void *buf, size_t nbytes, mdb_tgt_addr_t addr) { kt_data_t *kt = t->t_data; ssize_t rval; if ((rval = kt->k_kb_ops->kb_aread(kt->k_cookie, addr, buf, nbytes, as)) == -1) return (set_errno(EMDB_NOMAP)); return (rval); } ssize_t kt_awrite(mdb_tgt_t *t, mdb_tgt_as_t as, const void *buf, size_t nbytes, mdb_tgt_addr_t addr) { kt_data_t *kt = t->t_data; ssize_t rval; if ((rval = kt->k_kb_ops->kb_awrite(kt->k_cookie, addr, buf, nbytes, as)) == -1) return (set_errno(EMDB_NOMAP)); return (rval); } ssize_t kt_vread(mdb_tgt_t *t, void *buf, size_t nbytes, uintptr_t addr) { kt_data_t *kt = t->t_data; ssize_t rval; if ((rval = kt->k_kb_ops->kb_kread(kt->k_cookie, addr, buf, nbytes)) == -1) return (set_errno(EMDB_NOMAP)); return (rval); } ssize_t kt_vwrite(mdb_tgt_t *t, const void *buf, size_t nbytes, uintptr_t addr) { kt_data_t *kt = t->t_data; ssize_t rval; if ((rval = kt->k_kb_ops->kb_kwrite(kt->k_cookie, addr, buf, nbytes)) == -1) return (set_errno(EMDB_NOMAP)); return (rval); } ssize_t kt_fread(mdb_tgt_t *t, void *buf, size_t nbytes, uintptr_t addr) { return (kt_vread(t, buf, nbytes, addr)); } ssize_t kt_fwrite(mdb_tgt_t *t, const void *buf, size_t nbytes, uintptr_t addr) { return (kt_vwrite(t, buf, nbytes, addr)); } ssize_t kt_pread(mdb_tgt_t *t, void *buf, size_t nbytes, physaddr_t addr) { kt_data_t *kt = t->t_data; ssize_t rval; if ((rval = kt->k_kb_ops->kb_pread(kt->k_cookie, addr, buf, nbytes)) == -1) return (set_errno(EMDB_NOMAP)); return (rval); } ssize_t kt_pwrite(mdb_tgt_t *t, const void *buf, size_t nbytes, physaddr_t addr) { kt_data_t *kt = t->t_data; ssize_t rval; if ((rval = kt->k_kb_ops->kb_pwrite(kt->k_cookie, addr, buf, nbytes)) == -1) return (set_errno(EMDB_NOMAP)); return (rval); } int kt_vtop(mdb_tgt_t *t, mdb_tgt_as_t as, uintptr_t va, physaddr_t *pap) { kt_data_t *kt = t->t_data; struct as *asp; physaddr_t pa; mdb_module_t *mod; mdb_var_t *v; int (*fptr)(uintptr_t, struct as *, physaddr_t *); switch ((uintptr_t)as) { case (uintptr_t)MDB_TGT_AS_PHYS: case (uintptr_t)MDB_TGT_AS_FILE: case (uintptr_t)MDB_TGT_AS_IO: return (set_errno(EINVAL)); case (uintptr_t)MDB_TGT_AS_VIRT: case (uintptr_t)MDB_TGT_AS_VIRT_I: case (uintptr_t)MDB_TGT_AS_VIRT_S: asp = kt->k_as; break; default: asp = (struct as *)as; } if ((pa = kt->k_kb_ops->kb_vtop(kt->k_cookie, asp, va)) != -1ULL) { *pap = pa; return (0); } if ((v = mdb_nv_lookup(&mdb.m_modules, "unix")) != NULL && (mod = mdb_nv_get_cookie(v)) != NULL) { fptr = (int (*)(uintptr_t, struct as *, physaddr_t *)) dlsym(mod->mod_hdl, "platform_vtop"); if ((fptr != NULL) && ((*fptr)(va, asp, pap) == 0)) return (0); } return (set_errno(EMDB_NOMAP)); } int kt_lookup_by_name(mdb_tgt_t *t, const char *obj, const char *name, GElf_Sym *symp, mdb_syminfo_t *sip) { kt_data_t *kt = t->t_data; kt_module_t *km, kmod; mdb_var_t *v; int n; /* * To simplify the implementation, we create a fake module on the stack * which is "prepended" to k_modlist and whose symtab is kt->k_symtab. */ kmod.km_symtab = kt->k_symtab; kmod.km_list.ml_next = mdb_list_next(&kt->k_modlist); switch ((uintptr_t)obj) { case (uintptr_t)MDB_TGT_OBJ_EXEC: km = &kmod; n = 1; break; case (uintptr_t)MDB_TGT_OBJ_EVERY: km = &kmod; n = mdb_nv_size(&kt->k_modules) + 1; break; case (uintptr_t)MDB_TGT_OBJ_RTLD: obj = kt->k_rtld_name; /*FALLTHRU*/ default: if ((v = mdb_nv_lookup(&kt->k_modules, obj)) == NULL) return (set_errno(EMDB_NOOBJ)); km = mdb_nv_get_cookie(v); n = 1; if (km->km_symtab == NULL) kt_load_module(kt, t, km); } for (; n > 0; n--, km = mdb_list_next(km)) { if (mdb_gelf_symtab_lookup_by_name(km->km_symtab, name, symp, &sip->sym_id) == 0) { sip->sym_table = MDB_TGT_SYMTAB; return (0); } } return (set_errno(EMDB_NOSYM)); } int kt_lookup_by_addr(mdb_tgt_t *t, uintptr_t addr, uint_t flags, char *buf, size_t nbytes, GElf_Sym *symp, mdb_syminfo_t *sip) { kt_data_t *kt = t->t_data; kt_module_t kmods[3], *kmods_begin = &kmods[0], *kmods_end; const char *name; kt_module_t *km = &kmods[0]; /* Point km at first fake module */ kt_module_t *sym_km = NULL; /* Module associated with best sym */ GElf_Sym sym; /* Best symbol found so far if !exact */ uint_t symid; /* ID of best symbol found so far */ /* * To simplify the implementation, we create fake modules on the stack * that are "prepended" to k_modlist and whose symtab is set to * each of three special symbol tables, in order of precedence. */ km->km_symtab = mdb.m_prsym; if (kt->k_symtab != NULL) { km->km_list.ml_next = (mdb_list_t *)(km + 1); km = mdb_list_next(km); km->km_symtab = kt->k_symtab; } if (kt->k_dynsym != NULL) { km->km_list.ml_next = (mdb_list_t *)(km + 1); km = mdb_list_next(km); km->km_symtab = kt->k_dynsym; } km->km_list.ml_next = mdb_list_next(&kt->k_modlist); kmods_end = km; /* * Now iterate over the list of fake and real modules. If the module * has no symbol table and the address is in the text section, * instantiate the module's symbol table. In exact mode, we can * jump to 'found' immediately if we match. Otherwise we continue * looking and improve our choice if we find a closer symbol. */ for (km = &kmods[0]; km != NULL; km = mdb_list_next(km)) { if (km->km_symtab == NULL && addr >= km->km_text_va && addr < km->km_text_va + km->km_text_size) kt_load_module(kt, t, km); if (mdb_gelf_symtab_lookup_by_addr(km->km_symtab, addr, flags, buf, nbytes, symp, &sip->sym_id) != 0 || symp->st_value == 0) continue; if (flags & MDB_TGT_SYM_EXACT) { sym_km = km; goto found; } if (sym_km == NULL || mdb_gelf_sym_closer(symp, &sym, addr)) { sym_km = km; sym = *symp; symid = sip->sym_id; } } if (sym_km == NULL) return (set_errno(EMDB_NOSYMADDR)); *symp = sym; /* Copy our best symbol into the caller's symbol */ sip->sym_id = symid; found: /* * Once we've found something, copy the final name into the caller's * buffer and prefix it with the load object name if appropriate. */ if (sym_km != NULL) { name = mdb_gelf_sym_name(sym_km->km_symtab, symp); if (sym_km < kmods_begin || sym_km > kmods_end) { (void) mdb_snprintf(buf, nbytes, "%s`%s", sym_km->km_name, name); } else if (nbytes > 0) { (void) strncpy(buf, name, nbytes); buf[nbytes - 1] = '\0'; } if (sym_km->km_symtab == mdb.m_prsym) sip->sym_table = MDB_TGT_PRVSYM; else sip->sym_table = MDB_TGT_SYMTAB; } else { sip->sym_table = MDB_TGT_SYMTAB; } return (0); } static int kt_symtab_func(void *data, const GElf_Sym *sym, const char *name, uint_t id) { kt_symarg_t *argp = data; if (mdb_tgt_sym_match(sym, argp->sym_type)) { argp->sym_info.sym_id = id; return (argp->sym_cb(argp->sym_data, sym, name, &argp->sym_info, argp->sym_obj)); } return (0); } static void kt_symtab_iter(mdb_gelf_symtab_t *gst, uint_t type, const char *obj, mdb_tgt_sym_f *cb, void *p) { kt_symarg_t arg; arg.sym_cb = cb; arg.sym_data = p; arg.sym_type = type; arg.sym_info.sym_table = gst->gst_tabid; arg.sym_obj = obj; mdb_gelf_symtab_iter(gst, kt_symtab_func, &arg); } int kt_symbol_iter(mdb_tgt_t *t, const char *obj, uint_t which, uint_t type, mdb_tgt_sym_f *cb, void *data) { kt_data_t *kt = t->t_data; kt_module_t *km; mdb_gelf_symtab_t *symtab = NULL; mdb_var_t *v; switch ((uintptr_t)obj) { case (uintptr_t)MDB_TGT_OBJ_EXEC: if (which == MDB_TGT_SYMTAB) symtab = kt->k_symtab; else symtab = kt->k_dynsym; break; case (uintptr_t)MDB_TGT_OBJ_EVERY: if (which == MDB_TGT_DYNSYM) { symtab = kt->k_dynsym; obj = MDB_TGT_OBJ_EXEC; break; } mdb_nv_rewind(&kt->k_modules); while ((v = mdb_nv_advance(&kt->k_modules)) != NULL) { km = mdb_nv_get_cookie(v); if (km->km_symtab == NULL) kt_load_module(kt, t, km); if (km->km_symtab != NULL) kt_symtab_iter(km->km_symtab, type, km->km_name, cb, data); } break; case (uintptr_t)MDB_TGT_OBJ_RTLD: obj = kt->k_rtld_name; /*FALLTHRU*/ default: v = mdb_nv_lookup(&kt->k_modules, obj); if (v == NULL) return (set_errno(EMDB_NOOBJ)); km = mdb_nv_get_cookie(v); if (km->km_symtab == NULL) kt_load_module(kt, t, km); symtab = km->km_symtab; } if (symtab) kt_symtab_iter(symtab, type, obj, cb, data); return (0); } static int kt_mapping_walk(uintptr_t addr, const void *data, kt_maparg_t *marg) { /* * This is a bit sketchy but avoids problematic compilation of this * target against the current VM implementation. Now that we have * vmem, we can make this less broken and more informative by changing * this code to invoke the vmem walker in the near future. */ const struct kt_seg { caddr_t s_base; size_t s_size; } *segp = (const struct kt_seg *)data; mdb_map_t map; GElf_Sym sym; mdb_syminfo_t info; map.map_base = (uintptr_t)segp->s_base; map.map_size = segp->s_size; map.map_flags = MDB_TGT_MAP_R | MDB_TGT_MAP_W | MDB_TGT_MAP_X; if (kt_lookup_by_addr(marg->map_target, addr, MDB_TGT_SYM_EXACT, map.map_name, MDB_TGT_MAPSZ, &sym, &info) == -1) { (void) mdb_iob_snprintf(map.map_name, MDB_TGT_MAPSZ, "%lr", addr); } return (marg->map_cb(marg->map_data, &map, map.map_name)); } int kt_mapping_iter(mdb_tgt_t *t, mdb_tgt_map_f *func, void *private) { kt_data_t *kt = t->t_data; kt_maparg_t m; m.map_target = t; m.map_cb = func; m.map_data = private; return (mdb_pwalk("seg", (mdb_walk_cb_t)kt_mapping_walk, &m, (uintptr_t)kt->k_as)); } static const mdb_map_t * kt_module_to_map(kt_module_t *km, mdb_map_t *map) { (void) strncpy(map->map_name, km->km_name, MDB_TGT_MAPSZ); map->map_name[MDB_TGT_MAPSZ - 1] = '\0'; map->map_base = km->km_text_va; map->map_size = km->km_text_size; map->map_flags = MDB_TGT_MAP_R | MDB_TGT_MAP_W | MDB_TGT_MAP_X; return (map); } int kt_object_iter(mdb_tgt_t *t, mdb_tgt_map_f *func, void *private) { kt_data_t *kt = t->t_data; kt_module_t *km; mdb_map_t m; for (km = mdb_list_next(&kt->k_modlist); km; km = mdb_list_next(km)) { if (func(private, kt_module_to_map(km, &m), km->km_name) == -1) break; } return (0); } const mdb_map_t * kt_addr_to_map(mdb_tgt_t *t, uintptr_t addr) { kt_data_t *kt = t->t_data; kt_module_t *km; for (km = mdb_list_next(&kt->k_modlist); km; km = mdb_list_next(km)) { if (addr - km->km_text_va < km->km_text_size || addr - km->km_data_va < km->km_data_size || addr - km->km_bss_va < km->km_bss_size) return (kt_module_to_map(km, &kt->k_map)); } (void) set_errno(EMDB_NOMAP); return (NULL); } const mdb_map_t * kt_name_to_map(mdb_tgt_t *t, const char *name) { kt_data_t *kt = t->t_data; kt_module_t *km; mdb_map_t m; /* * If name is MDB_TGT_OBJ_EXEC, return the first module on the list, * which will be unix since we keep k_modlist in load order. */ if (name == MDB_TGT_OBJ_EXEC) return (kt_module_to_map(mdb_list_next(&kt->k_modlist), &m)); if (name == MDB_TGT_OBJ_RTLD) name = kt->k_rtld_name; if ((km = kt_module_by_name(kt, name)) != NULL) return (kt_module_to_map(km, &m)); (void) set_errno(EMDB_NOOBJ); return (NULL); } static ctf_file_t * kt_load_ctfdata(mdb_tgt_t *t, kt_module_t *km) { kt_data_t *kt = t->t_data; int err; if (km->km_ctfp != NULL) return (km->km_ctfp); if (km->km_ctf_va == 0) { (void) set_errno(EMDB_NOCTF); return (NULL); } if (km->km_symtab == NULL) kt_load_module(t->t_data, t, km); if ((km->km_ctf_buf = mdb_alloc(km->km_ctf_size, UM_NOSLEEP)) == NULL) { warn("failed to allocate memory to load %s debugging " "information", km->km_name); return (NULL); } if (mdb_tgt_vread(t, km->km_ctf_buf, km->km_ctf_size, km->km_ctf_va) != km->km_ctf_size) { warn("failed to read %lu bytes of debug data for %s at %p", (ulong_t)km->km_ctf_size, km->km_name, (void *)km->km_ctf_va); mdb_free(km->km_ctf_buf, km->km_ctf_size); km->km_ctf_buf = NULL; return (NULL); } if ((km->km_ctfp = mdb_ctf_bufopen((const void *)km->km_ctf_buf, km->km_ctf_size, km->km_symbuf, &km->km_symtab_hdr, km->km_strtab, &km->km_strtab_hdr, &err)) == NULL) { mdb_free(km->km_ctf_buf, km->km_ctf_size); km->km_ctf_buf = NULL; (void) set_errno(ctf_to_errno(err)); return (NULL); } mdb_dprintf(MDB_DBG_KMOD, "loaded %lu bytes of CTF data for %s\n", (ulong_t)km->km_ctf_size, km->km_name); if (ctf_parent_name(km->km_ctfp) != NULL) { mdb_var_t *v; if ((v = mdb_nv_lookup(&kt->k_modules, ctf_parent_name(km->km_ctfp))) == NULL) { warn("failed to load CTF data for %s - parent %s not " "loaded\n", km->km_name, ctf_parent_name(km->km_ctfp)); } if (v != NULL) { kt_module_t *pm = mdb_nv_get_cookie(v); if (pm->km_ctfp == NULL) (void) kt_load_ctfdata(t, pm); if (pm->km_ctfp != NULL && ctf_import(km->km_ctfp, pm->km_ctfp) == CTF_ERR) { warn("failed to import parent types into " "%s: %s\n", km->km_name, ctf_errmsg(ctf_errno(km->km_ctfp))); } } } return (km->km_ctfp); } ctf_file_t * kt_addr_to_ctf(mdb_tgt_t *t, uintptr_t addr) { kt_data_t *kt = t->t_data; kt_module_t *km; for (km = mdb_list_next(&kt->k_modlist); km; km = mdb_list_next(km)) { if (addr - km->km_text_va < km->km_text_size || addr - km->km_data_va < km->km_data_size || addr - km->km_bss_va < km->km_bss_size) return (kt_load_ctfdata(t, km)); } (void) set_errno(EMDB_NOMAP); return (NULL); } ctf_file_t * kt_name_to_ctf(mdb_tgt_t *t, const char *name) { kt_data_t *kt = t->t_data; kt_module_t *km; if (name == MDB_TGT_OBJ_EXEC) name = KT_CTFPARENT; else if (name == MDB_TGT_OBJ_RTLD) name = kt->k_rtld_name; if ((km = kt_module_by_name(kt, name)) != NULL) return (kt_load_ctfdata(t, km)); (void) set_errno(EMDB_NOOBJ); return (NULL); } /*ARGSUSED*/ int kt_status(mdb_tgt_t *t, mdb_tgt_status_t *tsp) { kt_data_t *kt = t->t_data; bzero(tsp, sizeof (mdb_tgt_status_t)); tsp->st_state = (kt->k_xpv_domu || (kt->k_dumphdr != NULL)) ? MDB_TGT_DEAD : MDB_TGT_RUNNING; return (0); } static ssize_t kt_xd_dumphdr(mdb_tgt_t *t, void *buf, size_t nbytes) { kt_data_t *kt = t->t_data; if (buf == NULL && nbytes == 0) return (sizeof (dumphdr_t)); if (kt->k_dumphdr == NULL) return (set_errno(ENODATA)); nbytes = MIN(nbytes, sizeof (dumphdr_t)); bcopy(kt->k_dumphdr, buf, nbytes); return (nbytes); } void kt_destroy(mdb_tgt_t *t) { kt_data_t *kt = t->t_data; kt_module_t *km, *nkm; (void) mdb_module_unload(KT_MODULE, 0); if (kt->k_regs != NULL) mdb_free(kt->k_regs, kt->k_regsize); if (kt->k_symtab != NULL) mdb_gelf_symtab_destroy(kt->k_symtab); if (kt->k_dynsym != NULL) mdb_gelf_symtab_destroy(kt->k_dynsym); if (kt->k_dumphdr != NULL) mdb_free(kt->k_dumphdr, sizeof (dumphdr_t)); mdb_gelf_destroy(kt->k_file); (void) kt->k_kb_ops->kb_close(kt->k_cookie); for (km = mdb_list_next(&kt->k_modlist); km; km = nkm) { if (km->km_symtab) mdb_gelf_symtab_destroy(km->km_symtab); if (km->km_data) mdb_free(km->km_data, km->km_datasz); if (km->km_ctfp) ctf_close(km->km_ctfp); if (km->km_ctf_buf != NULL) mdb_free(km->km_ctf_buf, km->km_ctf_size); nkm = mdb_list_next(km); strfree(km->km_name); mdb_free(km, sizeof (kt_module_t)); } mdb_nv_destroy(&kt->k_modules); strfree(kt->k_kvmfile); if (kt->k_symfile != NULL) strfree(kt->k_symfile); mdb_free(kt, sizeof (kt_data_t)); } static int kt_data_stub(void) { return (-1); } int mdb_kvm_tgt_create(mdb_tgt_t *t, int argc, const char *argv[]) { kt_data_t *kt = mdb_zalloc(sizeof (kt_data_t), UM_SLEEP); mdb_kb_ops_t *kvm_kb_ops = libkvm_kb_ops(); int oflag = (t->t_flags & MDB_TGT_F_RDWR) ? O_RDWR : O_RDONLY; struct utsname uts; GElf_Sym sym; pgcnt_t pmem; if (argc == 2) { kt->k_symfile = strdup(argv[0]); kt->k_kvmfile = strdup(argv[1]); kt->k_cookie = kvm_kb_ops->kb_open(kt->k_symfile, kt->k_kvmfile, NULL, oflag, (char *)mdb.m_pname); if (kt->k_cookie == NULL) goto err; kt->k_xpv_domu = 0; kt->k_kb_ops = kvm_kb_ops; } else { #ifndef __x86 return (set_errno(EINVAL)); #else mdb_kb_ops_t *(*getops)(void); kt->k_symfile = NULL; kt->k_kvmfile = strdup(argv[0]); getops = (mdb_kb_ops_t *(*)())dlsym(RTLD_NEXT, "mdb_kb_ops"); /* * Load mdb_kb if it's not already loaded during * identification. */ if (getops == NULL) { (void) mdb_module_load("mdb_kb", MDB_MOD_GLOBAL | MDB_MOD_SILENT); getops = (mdb_kb_ops_t *(*)()) dlsym(RTLD_NEXT, "mdb_kb_ops"); } if (getops == NULL || (kt->k_kb_ops = getops()) == NULL) { warn("failed to load KVM backend ops\n"); goto err; } kt->k_cookie = kt->k_kb_ops->kb_open(NULL, kt->k_kvmfile, NULL, oflag, (char *)mdb.m_pname); if (kt->k_cookie == NULL) goto err; kt->k_xpv_domu = 1; #endif } if ((kt->k_fio = kt->k_kb_ops->kb_sym_io(kt->k_cookie, kt->k_symfile)) == NULL) goto err; if ((kt->k_file = mdb_gelf_create(kt->k_fio, ET_EXEC, GF_FILE)) == NULL) { mdb_io_destroy(kt->k_fio); goto err; } kt->k_symtab = mdb_gelf_symtab_create_file(kt->k_file, SHT_SYMTAB, MDB_TGT_SYMTAB); kt->k_dynsym = mdb_gelf_symtab_create_file(kt->k_file, SHT_DYNSYM, MDB_TGT_DYNSYM); if (mdb_gelf_symtab_lookup_by_name(kt->k_symtab, "kas", &sym, NULL) == -1) { warn("'kas' symbol is missing from kernel\n"); goto err; } kt->k_as = (struct as *)(uintptr_t)sym.st_value; if (mdb_gelf_symtab_lookup_by_name(kt->k_symtab, "platform", &sym, NULL) == -1) { warn("'platform' symbol is missing from kernel\n"); goto err; } if (kt->k_kb_ops->kb_kread(kt->k_cookie, sym.st_value, kt->k_platform, MAXNAMELEN) <= 0) { warn("failed to read 'platform' string from kernel"); goto err; } if (mdb_gelf_symtab_lookup_by_name(kt->k_symtab, "utsname", &sym, NULL) == -1) { warn("'utsname' symbol is missing from kernel\n"); goto err; } if (kt->k_kb_ops->kb_kread(kt->k_cookie, sym.st_value, &uts, sizeof (uts)) <= 0) { warn("failed to read 'utsname' struct from kernel"); goto err; } kt->k_dump_print_content = (void (*)())(uintptr_t)kt_data_stub; kt->k_dump_find_curproc = kt_data_stub; /* * We set k_ctfvalid based on the presence of the CTF vmem arena * symbol. The CTF members were added to the end of struct module at * the same time, so this allows us to know whether we can use them. */ if (mdb_gelf_symtab_lookup_by_name(kt->k_symtab, "ctf_arena", &sym, NULL) == 0 && !(mdb.m_flags & MDB_FL_NOCTF)) kt->k_ctfvalid = 1; (void) mdb_nv_create(&kt->k_modules, UM_SLEEP); t->t_pshandle = kt->k_cookie; t->t_data = kt; #if defined(__sparc) #if defined(__sparcv9) kt_sparcv9_init(t); #else kt_sparcv7_init(t); #endif #elif defined(__amd64) kt_amd64_init(t); #elif defined(__i386) kt_ia32_init(t); #else #error "unknown ISA" #endif /* * We read our representative thread ID (address) from the kernel's * global panic_thread. It will remain 0 if this is a live kernel. */ (void) mdb_tgt_readsym(t, MDB_TGT_AS_VIRT, &kt->k_tid, sizeof (void *), MDB_TGT_OBJ_EXEC, "panic_thread"); if ((mdb.m_flags & MDB_FL_ADB) && mdb_tgt_readsym(t, MDB_TGT_AS_VIRT, &pmem, sizeof (pmem), MDB_TGT_OBJ_EXEC, "physmem") == sizeof (pmem)) mdb_printf("physmem %lx\n", (ulong_t)pmem); /* * If this is not a live kernel or a hypervisor dump, read the dump * header. We don't have to sanity-check the header, as the open would * not have succeeded otherwise. */ if (!kt->k_xpv_domu && strcmp(kt->k_symfile, "/dev/ksyms") != 0) { mdb_io_t *vmcore; kt->k_dumphdr = mdb_alloc(sizeof (dumphdr_t), UM_SLEEP); if ((vmcore = mdb_fdio_create_path(NULL, kt->k_kvmfile, O_RDONLY, 0)) == NULL) { mdb_warn("failed to open %s", kt->k_kvmfile); goto err; } if (IOP_READ(vmcore, kt->k_dumphdr, sizeof (dumphdr_t)) != sizeof (dumphdr_t)) { mdb_warn("failed to read dump header"); mdb_io_destroy(vmcore); goto err; } mdb_io_destroy(vmcore); (void) mdb_tgt_xdata_insert(t, "dumphdr", "dump header structure", kt_xd_dumphdr); } return (0); err: if (kt->k_dumphdr != NULL) mdb_free(kt->k_dumphdr, sizeof (dumphdr_t)); if (kt->k_symtab != NULL) mdb_gelf_symtab_destroy(kt->k_symtab); if (kt->k_dynsym != NULL) mdb_gelf_symtab_destroy(kt->k_dynsym); if (kt->k_file != NULL) mdb_gelf_destroy(kt->k_file); if (kt->k_cookie != NULL) (void) kt->k_kb_ops->kb_close(kt->k_cookie); mdb_free(kt, sizeof (kt_data_t)); return (-1); } int mdb_kvm_is_dump(mdb_io_t *io) { dumphdr_t h; (void) IOP_SEEK(io, (off64_t)0L, SEEK_SET); return (IOP_READ(io, &h, sizeof (dumphdr_t)) == sizeof (dumphdr_t) && h.dump_magic == DUMP_MAGIC); } int mdb_kvm_is_compressed_dump(mdb_io_t *io) { dumphdr_t h; (void) IOP_SEEK(io, (off64_t)0L, SEEK_SET); return (IOP_READ(io, &h, sizeof (dumphdr_t)) == sizeof (dumphdr_t) && h.dump_magic == DUMP_MAGIC && (h.dump_flags & DF_COMPRESSED) != 0); }