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 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_kreg_impl.h>
50 #include <mdb/mdb_isautil.h>
51 #include <mdb/mdb_amd64util.h>
52 #include <mdb/kvm_isadep.h>
53 #include <mdb/mdb_kvm.h>
54 #include <mdb/mdb_err.h>
55 #include <mdb/mdb_debug.h>
56 #include <mdb/mdb.h>
57
58 /*ARGSUSED*/
59 int
kt_regs(uintptr_t addr,uint_t flags,int argc,const mdb_arg_t * argv)60 kt_regs(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
61 {
62 mdb_amd64_printregs((const mdb_tgt_gregset_t *)addr);
63 return (DCMD_OK);
64 }
65
66 static int
kt_stack_common(uintptr_t addr,uint_t flags,int argc,const mdb_arg_t * argv,mdb_tgt_stack_f * func)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 *)(uintptr_t)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_RBP] = 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 *)mdb_strtoull(argv->a_un.a_str);
87 else
88 arg = (void *)argv->a_un.a_val;
89 }
90
91 (void) mdb_amd64_kvm_stack_iter(mdb.m_target, grp, func, arg);
92 return (DCMD_OK);
93 }
94
95 int
kt_stack(uintptr_t addr,uint_t flags,int argc,const mdb_arg_t * argv)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_amd64_kvm_frame));
99 }
100
101 int
kt_stackv(uintptr_t addr,uint_t flags,int argc,const mdb_arg_t * argv)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_amd64_kvm_framev));
105 }
106
107 const mdb_tgt_ops_t kt_amd64_ops = {
108 .t_setflags = kt_setflags,
109 .t_setcontext = kt_setcontext,
110 .t_activate = kt_activate,
111 .t_deactivate = kt_deactivate,
112 .t_periodic = (void (*)())(uintptr_t)mdb_tgt_nop,
113 .t_destroy = kt_destroy,
114 .t_name = kt_name,
115 .t_isa = (const char *(*)())mdb_conf_isa,
116 .t_platform = kt_platform,
117 .t_uname = kt_uname,
118 .t_dmodel = kt_dmodel,
119 .t_aread = kt_aread,
120 .t_awrite = kt_awrite,
121 .t_vread = kt_vread,
122 .t_vwrite = kt_vwrite,
123 .t_pread = kt_pread,
124 .t_pwrite = kt_pwrite,
125 .t_fread = kt_fread,
126 .t_fwrite = kt_fwrite,
127 .t_ioread = (ssize_t (*)())mdb_tgt_notsup,
128 .t_iowrite = (ssize_t (*)())mdb_tgt_notsup,
129 .t_vtop = kt_vtop,
130 .t_lookup_by_name = kt_lookup_by_name,
131 .t_lookup_by_addr = kt_lookup_by_addr,
132 .t_symbol_iter = kt_symbol_iter,
133 .t_mapping_iter = kt_mapping_iter,
134 .t_object_iter = kt_object_iter,
135 .t_addr_to_map = kt_addr_to_map,
136 .t_name_to_map = kt_name_to_map,
137 .t_addr_to_ctf = kt_addr_to_ctf,
138 .t_name_to_ctf = kt_name_to_ctf,
139 .t_status = kt_status,
140 .t_run = (int (*)())(uintptr_t)mdb_tgt_notsup,
141 .t_step = (int (*)())(uintptr_t)mdb_tgt_notsup,
142 .t_step_out = (int (*)())(uintptr_t)mdb_tgt_notsup,
143 .t_next = (int (*)())(uintptr_t)mdb_tgt_notsup,
144 .t_cont = (int (*)())(uintptr_t)mdb_tgt_notsup,
145 .t_signal = (int (*)())(uintptr_t)mdb_tgt_notsup,
146 .t_add_vbrkpt = (int (*)())(uintptr_t)mdb_tgt_null,
147 .t_add_sbrkpt = (int (*)())(uintptr_t)mdb_tgt_null,
148 .t_add_pwapt = (int (*)())(uintptr_t)mdb_tgt_null,
149 .t_add_vwapt = (int (*)())(uintptr_t)mdb_tgt_null,
150 .t_add_iowapt = (int (*)())(uintptr_t)mdb_tgt_null,
151 .t_add_sysenter = (int (*)())(uintptr_t)mdb_tgt_null,
152 .t_add_sysexit = (int (*)())(uintptr_t)mdb_tgt_null,
153 .t_add_signal = (int (*)())(uintptr_t)mdb_tgt_null,
154 .t_add_fault = (int (*)())(uintptr_t)mdb_tgt_null,
155 .t_getareg = kt_getareg,
156 .t_putareg = kt_putareg,
157 .t_stack_iter = mdb_amd64_kvm_stack_iter,
158 .t_auxv = (int (*)())(uintptr_t)mdb_tgt_notsup,
159 .t_thread_name = (int (*)())(uintptr_t)mdb_tgt_notsup,
160 };
161
162 void
kt_regs_to_kregs(struct regs * regs,mdb_tgt_gregset_t * gregs)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_RDI] = regs->r_rdi;
168 gregs->kregs[KREG_RSI] = regs->r_rsi;
169 gregs->kregs[KREG_RDX] = regs->r_rdx;
170 gregs->kregs[KREG_RCX] = regs->r_rcx;
171 gregs->kregs[KREG_R8] = regs->r_r8;
172 gregs->kregs[KREG_R9] = regs->r_r9;
173 gregs->kregs[KREG_RAX] = regs->r_rax;
174 gregs->kregs[KREG_RBX] = regs->r_rbx;
175 gregs->kregs[KREG_RBP] = regs->r_rbp;
176 gregs->kregs[KREG_R10] = regs->r_r10;
177 gregs->kregs[KREG_R11] = regs->r_r11;
178 gregs->kregs[KREG_R12] = regs->r_r12;
179 gregs->kregs[KREG_R13] = regs->r_r13;
180 gregs->kregs[KREG_R14] = regs->r_r14;
181 gregs->kregs[KREG_R15] = regs->r_r15;
182 gregs->kregs[KREG_DS] = regs->r_ds;
183 gregs->kregs[KREG_ES] = regs->r_es;
184 gregs->kregs[KREG_FS] = regs->r_fs;
185 gregs->kregs[KREG_GS] = regs->r_gs;
186 gregs->kregs[KREG_TRAPNO] = regs->r_trapno;
187 gregs->kregs[KREG_ERR] = regs->r_err;
188 gregs->kregs[KREG_RIP] = regs->r_rip;
189 gregs->kregs[KREG_CS] = regs->r_cs;
190 gregs->kregs[KREG_RFLAGS] = regs->r_rfl;
191 gregs->kregs[KREG_RSP] = regs->r_rsp;
192 gregs->kregs[KREG_SS] = regs->r_ss;
193 }
194
195 void
kt_amd64_init(mdb_tgt_t * t)196 kt_amd64_init(mdb_tgt_t *t)
197 {
198 kt_data_t *kt = t->t_data;
199 panic_data_t pd;
200 struct regs regs;
201 uintptr_t addr;
202
203 /*
204 * Initialize the machine-dependent parts of the kernel target
205 * structure. Once this is complete and we fill in the ops
206 * vector, the target is now fully constructed and we can use
207 * the target API itself to perform the rest of our initialization.
208 */
209 kt->k_rds = mdb_amd64_kregs;
210 kt->k_regs = mdb_zalloc(sizeof (mdb_tgt_gregset_t), UM_SLEEP);
211 kt->k_regsize = sizeof (mdb_tgt_gregset_t);
212 kt->k_dcmd_regs = kt_regs;
213 kt->k_dcmd_stack = kt_stack;
214 kt->k_dcmd_stackv = kt_stackv;
215 kt->k_dcmd_stackr = kt_stackv;
216 kt->k_dcmd_cpustack = kt_cpustack;
217 kt->k_dcmd_cpuregs = kt_cpuregs;
218
219 t->t_ops = &kt_amd64_ops;
220
221 (void) mdb_dis_select("amd64");
222
223 /*
224 * Lookup the symbols corresponding to subroutines in locore.s where
225 * we expect a saved regs structure to be pushed on the stack. When
226 * performing stack tracebacks we will attempt to detect interrupt
227 * frames by comparing the %eip value to these symbols.
228 */
229 (void) mdb_tgt_lookup_by_name(t, MDB_TGT_OBJ_EXEC,
230 "cmnint", &kt->k_intr_sym, NULL);
231
232 (void) mdb_tgt_lookup_by_name(t, MDB_TGT_OBJ_EXEC,
233 "cmntrap", &kt->k_trap_sym, NULL);
234
235 /*
236 * Don't attempt to load any thread or register information if
237 * we're examining the live operating system.
238 */
239 if (kt->k_symfile != NULL && strcmp(kt->k_symfile, "/dev/ksyms") == 0)
240 return;
241
242 /*
243 * If the panicbuf symbol is present and we can consume a panicbuf
244 * header of the appropriate version from this address, then we can
245 * initialize our current register set based on its contents.
246 * Prior to the re-structuring of panicbuf, our only register data
247 * was the panic_regs label_t, into which a setjmp() was performed,
248 * or the panic_reg register pointer, which was only non-zero if
249 * the system panicked as a result of a trap calling die().
250 */
251 if (mdb_tgt_readsym(t, MDB_TGT_AS_VIRT, &pd, sizeof (pd),
252 MDB_TGT_OBJ_EXEC, "panicbuf") == sizeof (pd) &&
253 pd.pd_version == PANICBUFVERS) {
254
255 size_t pd_size = MIN(PANICBUFSIZE, pd.pd_msgoff);
256 panic_data_t *pdp = mdb_zalloc(pd_size, UM_SLEEP);
257 uint_t i, n;
258
259 (void) mdb_tgt_readsym(t, MDB_TGT_AS_VIRT, pdp, pd_size,
260 MDB_TGT_OBJ_EXEC, "panicbuf");
261
262 n = (pd_size - (sizeof (panic_data_t) -
263 sizeof (panic_nv_t))) / sizeof (panic_nv_t);
264
265 for (i = 0; i < n; i++) {
266 (void) kt_putareg(t, kt->k_tid,
267 pdp->pd_nvdata[i].pnv_name,
268 pdp->pd_nvdata[i].pnv_value);
269 }
270
271 mdb_free(pdp, pd_size);
272
273 return;
274 };
275
276 if (mdb_tgt_readsym(t, MDB_TGT_AS_VIRT, &addr, sizeof (addr),
277 MDB_TGT_OBJ_EXEC, "panic_reg") == sizeof (addr) && addr != 0 &&
278 mdb_tgt_vread(t, ®s, sizeof (regs), addr) == sizeof (regs)) {
279 kt_regs_to_kregs(®s, kt->k_regs);
280 return;
281 }
282
283 /*
284 * If we can't read any panic regs, then our final try is for any CPU
285 * context that may have been stored (for example, in Xen core dumps).
286 */
287 if (kt_kvmregs(t, 0, kt->k_regs) == 0)
288 return;
289
290 warn("failed to read panicbuf and panic_reg -- "
291 "current register set will be unavailable\n");
292 }
293