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 2025 Oxide Computer Company
27 */
28
29 /*
30 * Libkvm Kernel Target Intel 64-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/reg.h>
38 #include <sys/frame.h>
39 #include <sys/stack.h>
40 #include <sys/sysmacros.h>
41 #include <sys/panic.h>
42 #include <sys/privregs.h>
43 #include <strings.h>
44
45 #include <mdb/mdb_target_impl.h>
46 #include <mdb/mdb_disasm.h>
47 #include <mdb/mdb_modapi.h>
48 #include <mdb/mdb_conf.h>
49 #include <mdb/mdb_stack.h>
50 #include <mdb/mdb_kreg_impl.h>
51 #include <mdb/mdb_stack.h>
52 #include <mdb/mdb_isautil.h>
53 #include <mdb/mdb_amd64util.h>
54 #include <mdb/kvm_isadep.h>
55 #include <mdb/mdb_kvm.h>
56 #include <mdb/mdb_err.h>
57 #include <mdb/mdb_debug.h>
58 #include <mdb/mdb.h>
59
60 /*ARGSUSED*/
61 int
kt_regs(uintptr_t addr,uint_t flags,int argc,const mdb_arg_t * argv)62 kt_regs(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
63 {
64 mdb_amd64_printregs((const mdb_tgt_gregset_t *)addr);
65 return (DCMD_OK);
66 }
67
68 static int
kt_stack_common(uintptr_t addr,uint_t flags,int argc,const mdb_arg_t * argv,mdb_stack_frame_flags_t sflags,mdb_tgt_stack_f * func)69 kt_stack_common(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv,
70 mdb_stack_frame_flags_t sflags, mdb_tgt_stack_f *func)
71 {
72 mdb_tgt_t *t = mdb.m_target;
73 kt_data_t *kt = t->t_data;
74 mdb_tgt_gregset_t gregs, *grp;
75 mdb_stack_frame_hdl_t *hdl;
76 uint_t arglim = mdb.m_nargs;
77 int i;
78
79 if (flags & DCMD_ADDRSPEC) {
80 bzero(&gregs, sizeof (gregs));
81 gregs.kregs[KREG_RBP] = addr;
82 grp = &gregs;
83 } else {
84 grp = kt->k_regs;
85 }
86
87 i = mdb_getopts(argc, argv,
88 'n', MDB_OPT_SETBITS, MSF_ADDR, &sflags,
89 's', MDB_OPT_SETBITS, MSF_SIZES, &sflags,
90 't', MDB_OPT_SETBITS, MSF_TYPES, &sflags,
91 'v', MDB_OPT_SETBITS, MSF_VERBOSE, &sflags,
92 NULL);
93
94 argc -= i;
95 argv += i;
96
97 if (argc != 0) {
98 if (argv->a_type == MDB_TYPE_CHAR || argc > 1)
99 return (DCMD_USAGE);
100
101 arglim = mdb_argtoull(argv);
102 }
103
104 if ((hdl = mdb_stack_frame_init(t, arglim, sflags)) == NULL) {
105 mdb_warn("failed to init stack frame\n");
106 return (DCMD_ERR);
107 }
108
109 (void) mdb_amd64_kvm_stack_iter(t, grp, func, (void *)hdl);
110 return (DCMD_OK);
111 }
112
113 int
kt_stack(uintptr_t addr,uint_t flags,int argc,const mdb_arg_t * argv)114 kt_stack(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
115 {
116 return (kt_stack_common(addr, flags, argc, argv, 0,
117 mdb_amd64_kvm_frame));
118 }
119
120 int
kt_stackv(uintptr_t addr,uint_t flags,int argc,const mdb_arg_t * argv)121 kt_stackv(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
122 {
123 return (kt_stack_common(addr, flags, argc, argv,
124 MSF_VERBOSE, mdb_amd64_kvm_frame));
125 }
126
127 const mdb_tgt_ops_t kt_amd64_ops = {
128 .t_setflags = kt_setflags,
129 .t_setcontext = kt_setcontext,
130 .t_activate = kt_activate,
131 .t_deactivate = kt_deactivate,
132 .t_periodic = (void (*)())(uintptr_t)mdb_tgt_nop,
133 .t_destroy = kt_destroy,
134 .t_name = kt_name,
135 .t_isa = (const char *(*)())mdb_conf_isa,
136 .t_platform = kt_platform,
137 .t_uname = kt_uname,
138 .t_dmodel = kt_dmodel,
139 .t_aread = kt_aread,
140 .t_awrite = kt_awrite,
141 .t_vread = kt_vread,
142 .t_vwrite = kt_vwrite,
143 .t_pread = kt_pread,
144 .t_pwrite = kt_pwrite,
145 .t_fread = kt_fread,
146 .t_fwrite = kt_fwrite,
147 .t_ioread = (ssize_t (*)())mdb_tgt_notsup,
148 .t_iowrite = (ssize_t (*)())mdb_tgt_notsup,
149 .t_vtop = kt_vtop,
150 .t_lookup_by_name = kt_lookup_by_name,
151 .t_lookup_by_addr = kt_lookup_by_addr,
152 .t_symbol_iter = kt_symbol_iter,
153 .t_mapping_iter = kt_mapping_iter,
154 .t_object_iter = kt_object_iter,
155 .t_addr_to_map = kt_addr_to_map,
156 .t_name_to_map = kt_name_to_map,
157 .t_addr_to_ctf = kt_addr_to_ctf,
158 .t_name_to_ctf = kt_name_to_ctf,
159 .t_status = kt_status,
160 .t_run = (int (*)())(uintptr_t)mdb_tgt_notsup,
161 .t_step = (int (*)())(uintptr_t)mdb_tgt_notsup,
162 .t_step_out = (int (*)())(uintptr_t)mdb_tgt_notsup,
163 .t_next = (int (*)())(uintptr_t)mdb_tgt_notsup,
164 .t_cont = (int (*)())(uintptr_t)mdb_tgt_notsup,
165 .t_signal = (int (*)())(uintptr_t)mdb_tgt_notsup,
166 .t_add_vbrkpt = (int (*)())(uintptr_t)mdb_tgt_null,
167 .t_add_sbrkpt = (int (*)())(uintptr_t)mdb_tgt_null,
168 .t_add_pwapt = (int (*)())(uintptr_t)mdb_tgt_null,
169 .t_add_vwapt = (int (*)())(uintptr_t)mdb_tgt_null,
170 .t_add_iowapt = (int (*)())(uintptr_t)mdb_tgt_null,
171 .t_add_sysenter = (int (*)())(uintptr_t)mdb_tgt_null,
172 .t_add_sysexit = (int (*)())(uintptr_t)mdb_tgt_null,
173 .t_add_signal = (int (*)())(uintptr_t)mdb_tgt_null,
174 .t_add_fault = (int (*)())(uintptr_t)mdb_tgt_null,
175 .t_getareg = kt_getareg,
176 .t_putareg = kt_putareg,
177 .t_stack_iter = mdb_amd64_kvm_stack_iter,
178 .t_auxv = (int (*)())(uintptr_t)mdb_tgt_notsup,
179 .t_thread_name = (int (*)())(uintptr_t)mdb_tgt_notsup,
180 };
181
182 void
kt_regs_to_kregs(struct regs * regs,mdb_tgt_gregset_t * gregs)183 kt_regs_to_kregs(struct regs *regs, mdb_tgt_gregset_t *gregs)
184 {
185 gregs->kregs[KREG_SAVFP] = regs->r_savfp;
186 gregs->kregs[KREG_SAVPC] = regs->r_savpc;
187 gregs->kregs[KREG_RDI] = regs->r_rdi;
188 gregs->kregs[KREG_RSI] = regs->r_rsi;
189 gregs->kregs[KREG_RDX] = regs->r_rdx;
190 gregs->kregs[KREG_RCX] = regs->r_rcx;
191 gregs->kregs[KREG_R8] = regs->r_r8;
192 gregs->kregs[KREG_R9] = regs->r_r9;
193 gregs->kregs[KREG_RAX] = regs->r_rax;
194 gregs->kregs[KREG_RBX] = regs->r_rbx;
195 gregs->kregs[KREG_RBP] = regs->r_rbp;
196 gregs->kregs[KREG_R10] = regs->r_r10;
197 gregs->kregs[KREG_R11] = regs->r_r11;
198 gregs->kregs[KREG_R12] = regs->r_r12;
199 gregs->kregs[KREG_R13] = regs->r_r13;
200 gregs->kregs[KREG_R14] = regs->r_r14;
201 gregs->kregs[KREG_R15] = regs->r_r15;
202 gregs->kregs[KREG_DS] = regs->r_ds;
203 gregs->kregs[KREG_ES] = regs->r_es;
204 gregs->kregs[KREG_FS] = regs->r_fs;
205 gregs->kregs[KREG_GS] = regs->r_gs;
206 gregs->kregs[KREG_TRAPNO] = regs->r_trapno;
207 gregs->kregs[KREG_ERR] = regs->r_err;
208 gregs->kregs[KREG_RIP] = regs->r_rip;
209 gregs->kregs[KREG_CS] = regs->r_cs;
210 gregs->kregs[KREG_RFLAGS] = regs->r_rfl;
211 gregs->kregs[KREG_RSP] = regs->r_rsp;
212 gregs->kregs[KREG_SS] = regs->r_ss;
213 }
214
215 void
kt_amd64_init(mdb_tgt_t * t)216 kt_amd64_init(mdb_tgt_t *t)
217 {
218 kt_data_t *kt = t->t_data;
219 panic_data_t pd;
220 struct regs regs;
221 uintptr_t addr;
222
223 /*
224 * Initialize the machine-dependent parts of the kernel target
225 * structure. Once this is complete and we fill in the ops
226 * vector, the target is now fully constructed and we can use
227 * the target API itself to perform the rest of our initialization.
228 */
229 kt->k_rds = mdb_amd64_kregs;
230 kt->k_regs = mdb_zalloc(sizeof (mdb_tgt_gregset_t), UM_SLEEP);
231 kt->k_regsize = sizeof (mdb_tgt_gregset_t);
232 kt->k_dcmd_regs = kt_regs;
233 kt->k_dcmd_stack = kt_stack;
234 kt->k_dcmd_stackv = kt_stackv;
235 kt->k_dcmd_stackr = kt_stackv;
236 kt->k_dcmd_cpustack = kt_cpustack;
237 kt->k_dcmd_cpuregs = kt_cpuregs;
238
239 t->t_ops = &kt_amd64_ops;
240
241 (void) mdb_dis_select("amd64");
242
243 /*
244 * Lookup the symbols corresponding to subroutines in locore.s where
245 * we expect a saved regs structure to be pushed on the stack. When
246 * performing stack tracebacks we will attempt to detect interrupt
247 * frames by comparing the %eip value to these symbols.
248 */
249 (void) mdb_tgt_lookup_by_name(t, MDB_TGT_OBJ_EXEC,
250 "cmnint", &kt->k_intr_sym, NULL);
251
252 (void) mdb_tgt_lookup_by_name(t, MDB_TGT_OBJ_EXEC,
253 "cmntrap", &kt->k_trap_sym, NULL);
254
255 /*
256 * Don't attempt to load any thread or register information if
257 * we're examining the live operating system.
258 */
259 if (kt->k_symfile != NULL && strcmp(kt->k_symfile, "/dev/ksyms") == 0)
260 return;
261
262 /*
263 * If the panicbuf symbol is present and we can consume a panicbuf
264 * header of the appropriate version from this address, then we can
265 * initialize our current register set based on its contents.
266 * Prior to the re-structuring of panicbuf, our only register data
267 * was the panic_regs label_t, into which a setjmp() was performed,
268 * or the panic_reg register pointer, which was only non-zero if
269 * the system panicked as a result of a trap calling die().
270 */
271 if (mdb_tgt_readsym(t, MDB_TGT_AS_VIRT, &pd, sizeof (pd),
272 MDB_TGT_OBJ_EXEC, "panicbuf") == sizeof (pd) &&
273 pd.pd_version == PANICBUFVERS) {
274
275 size_t pd_size = MIN(PANICBUFSIZE, pd.pd_msgoff);
276 panic_data_t *pdp = mdb_zalloc(pd_size, UM_SLEEP);
277 uint_t i, n;
278
279 (void) mdb_tgt_readsym(t, MDB_TGT_AS_VIRT, pdp, pd_size,
280 MDB_TGT_OBJ_EXEC, "panicbuf");
281
282 n = (pd_size - (sizeof (panic_data_t) -
283 sizeof (panic_nv_t))) / sizeof (panic_nv_t);
284
285 for (i = 0; i < n; i++) {
286 (void) kt_putareg(t, kt->k_tid,
287 pdp->pd_nvdata[i].pnv_name,
288 pdp->pd_nvdata[i].pnv_value);
289 }
290
291 mdb_free(pdp, pd_size);
292
293 return;
294 };
295
296 if (mdb_tgt_readsym(t, MDB_TGT_AS_VIRT, &addr, sizeof (addr),
297 MDB_TGT_OBJ_EXEC, "panic_reg") == sizeof (addr) && addr != 0 &&
298 mdb_tgt_vread(t, ®s, sizeof (regs), addr) == sizeof (regs)) {
299 kt_regs_to_kregs(®s, kt->k_regs);
300 return;
301 }
302
303 /*
304 * If we can't read any panic regs, then our final try is for any CPU
305 * context that may have been stored (for example, in Xen core dumps).
306 */
307 if (kt_kvmregs(t, 0, kt->k_regs) == 0)
308 return;
309
310 warn("failed to read panicbuf and panic_reg -- "
311 "current register set will be unavailable\n");
312 }
313