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 /*
23 * Copyright 2007 Sun Microsystems, Inc. All rights reserved.
24 * Use is subject to license terms.
25 */
26 /*
27 * Copyright (c) 2018, Joyent, Inc. All rights reserved.
28 * Copyright 2014 Nexenta Systems, Inc. All rights reserved.
29 * Copyright (c) 2013 by Delphix. All rights reserved.
30 */
31
32 #include <sys/types.h>
33 #include <sys/reg.h>
34 #include <sys/privregs.h>
35 #include <sys/stack.h>
36 #include <sys/frame.h>
37
38 #include <mdb/mdb_target_impl.h>
39 #include <mdb/mdb_kreg_impl.h>
40 #include <mdb/mdb_debug.h>
41 #include <mdb/mdb_modapi.h>
42 #include <mdb/mdb_amd64util.h>
43 #include <mdb/mdb_ctf.h>
44 #include <mdb/mdb_err.h>
45 #include <mdb/mdb.h>
46
47 #include <saveargs.h>
48
49 /*
50 * This array is used by the getareg and putareg entry points, and also by our
51 * register variable discipline.
52 */
53
54 const mdb_tgt_regdesc_t mdb_amd64_kregs[] = {
55 { "savfp", KREG_SAVFP, MDB_TGT_R_EXPORT },
56 { "savpc", KREG_SAVPC, MDB_TGT_R_EXPORT },
57 { "rdi", KREG_RDI, MDB_TGT_R_EXPORT },
58 { "edi", KREG_RDI, MDB_TGT_R_EXPORT | MDB_TGT_R_32 },
59 { "di", KREG_RDI, MDB_TGT_R_EXPORT | MDB_TGT_R_16 },
60 { "dil", KREG_RDI, MDB_TGT_R_EXPORT | MDB_TGT_R_8L },
61 { "rsi", KREG_RSI, MDB_TGT_R_EXPORT },
62 { "esi", KREG_RSI, MDB_TGT_R_EXPORT | MDB_TGT_R_32 },
63 { "si", KREG_RSI, MDB_TGT_R_EXPORT | MDB_TGT_R_16 },
64 { "sil", KREG_RSI, MDB_TGT_R_EXPORT | MDB_TGT_R_8L },
65 { "rdx", KREG_RDX, MDB_TGT_R_EXPORT },
66 { "edx", KREG_RDX, MDB_TGT_R_EXPORT | MDB_TGT_R_32 },
67 { "dx", KREG_RDX, MDB_TGT_R_EXPORT | MDB_TGT_R_16 },
68 { "dh", KREG_RDX, MDB_TGT_R_EXPORT | MDB_TGT_R_8H },
69 { "dl", KREG_RDX, MDB_TGT_R_EXPORT | MDB_TGT_R_8L },
70 { "rcx", KREG_RCX, MDB_TGT_R_EXPORT },
71 { "ecx", KREG_RCX, MDB_TGT_R_EXPORT | MDB_TGT_R_32 },
72 { "cx", KREG_RCX, MDB_TGT_R_EXPORT | MDB_TGT_R_16 },
73 { "ch", KREG_RCX, MDB_TGT_R_EXPORT | MDB_TGT_R_8H },
74 { "cl", KREG_RCX, MDB_TGT_R_EXPORT | MDB_TGT_R_8L },
75 { "r8", KREG_R8, MDB_TGT_R_EXPORT },
76 { "r8d", KREG_R8, MDB_TGT_R_EXPORT | MDB_TGT_R_32 },
77 { "r8w", KREG_R8, MDB_TGT_R_EXPORT | MDB_TGT_R_16 },
78 { "r8l", KREG_R8, MDB_TGT_R_EXPORT | MDB_TGT_R_8L },
79 { "r9", KREG_R9, MDB_TGT_R_EXPORT },
80 { "r9d", KREG_R8, MDB_TGT_R_EXPORT | MDB_TGT_R_32 },
81 { "r9w", KREG_R8, MDB_TGT_R_EXPORT | MDB_TGT_R_16 },
82 { "r9l", KREG_R8, MDB_TGT_R_EXPORT | MDB_TGT_R_8L },
83 { "rax", KREG_RAX, MDB_TGT_R_EXPORT },
84 { "eax", KREG_RAX, MDB_TGT_R_EXPORT | MDB_TGT_R_32 },
85 { "ax", KREG_RAX, MDB_TGT_R_EXPORT | MDB_TGT_R_16 },
86 { "ah", KREG_RAX, MDB_TGT_R_EXPORT | MDB_TGT_R_8H },
87 { "al", KREG_RAX, MDB_TGT_R_EXPORT | MDB_TGT_R_8L },
88 { "rbx", KREG_RBX, MDB_TGT_R_EXPORT },
89 { "ebx", KREG_RBX, MDB_TGT_R_EXPORT | MDB_TGT_R_32 },
90 { "bx", KREG_RBX, MDB_TGT_R_EXPORT | MDB_TGT_R_16 },
91 { "bh", KREG_RBX, MDB_TGT_R_EXPORT | MDB_TGT_R_8H },
92 { "bl", KREG_RBX, MDB_TGT_R_EXPORT | MDB_TGT_R_8L },
93 { "rbp", KREG_RBP, MDB_TGT_R_EXPORT },
94 { "ebp", KREG_RBP, MDB_TGT_R_EXPORT | MDB_TGT_R_32 },
95 { "bp", KREG_RBP, MDB_TGT_R_EXPORT | MDB_TGT_R_16 },
96 { "bpl", KREG_RBP, MDB_TGT_R_EXPORT | MDB_TGT_R_8L },
97 { "r10", KREG_R10, MDB_TGT_R_EXPORT },
98 { "r10d", KREG_R10, MDB_TGT_R_EXPORT | MDB_TGT_R_32 },
99 { "r10w", KREG_R10, MDB_TGT_R_EXPORT | MDB_TGT_R_16 },
100 { "r10l", KREG_R10, MDB_TGT_R_EXPORT | MDB_TGT_R_8L },
101 { "r11", KREG_R11, MDB_TGT_R_EXPORT },
102 { "r11d", KREG_R11, MDB_TGT_R_EXPORT | MDB_TGT_R_32 },
103 { "r11w", KREG_R11, MDB_TGT_R_EXPORT | MDB_TGT_R_16 },
104 { "r11l", KREG_R11, MDB_TGT_R_EXPORT | MDB_TGT_R_8L },
105 { "r12", KREG_R12, MDB_TGT_R_EXPORT },
106 { "r12d", KREG_R12, MDB_TGT_R_EXPORT | MDB_TGT_R_32 },
107 { "r12w", KREG_R12, MDB_TGT_R_EXPORT | MDB_TGT_R_16 },
108 { "r12l", KREG_R12, MDB_TGT_R_EXPORT | MDB_TGT_R_8L },
109 { "r13", KREG_R13, MDB_TGT_R_EXPORT },
110 { "r13d", KREG_R13, MDB_TGT_R_EXPORT | MDB_TGT_R_32 },
111 { "r13w", KREG_R13, MDB_TGT_R_EXPORT | MDB_TGT_R_16 },
112 { "r13l", KREG_R13, MDB_TGT_R_EXPORT | MDB_TGT_R_8L },
113 { "r14", KREG_R14, MDB_TGT_R_EXPORT },
114 { "r14d", KREG_R14, MDB_TGT_R_EXPORT | MDB_TGT_R_32 },
115 { "r14w", KREG_R14, MDB_TGT_R_EXPORT | MDB_TGT_R_16 },
116 { "r14l", KREG_R14, MDB_TGT_R_EXPORT | MDB_TGT_R_8L },
117 { "r15", KREG_R15, MDB_TGT_R_EXPORT },
118 { "r15d", KREG_R15, MDB_TGT_R_EXPORT | MDB_TGT_R_32 },
119 { "r15w", KREG_R15, MDB_TGT_R_EXPORT | MDB_TGT_R_16 },
120 { "r15l", KREG_R15, MDB_TGT_R_EXPORT | MDB_TGT_R_8L },
121 { "ds", KREG_DS, MDB_TGT_R_EXPORT },
122 { "es", KREG_ES, MDB_TGT_R_EXPORT },
123 { "fs", KREG_FS, MDB_TGT_R_EXPORT },
124 { "gs", KREG_GS, MDB_TGT_R_EXPORT },
125 { "trapno", KREG_TRAPNO, MDB_TGT_R_EXPORT | MDB_TGT_R_PRIV },
126 { "err", KREG_ERR, MDB_TGT_R_EXPORT | MDB_TGT_R_PRIV },
127 { "rip", KREG_RIP, MDB_TGT_R_EXPORT },
128 { "cs", KREG_CS, MDB_TGT_R_EXPORT },
129 { "rflags", KREG_RFLAGS, MDB_TGT_R_EXPORT },
130 { "eflags", KREG_RFLAGS, MDB_TGT_R_EXPORT | MDB_TGT_R_32 },
131 { "rsp", KREG_RSP, MDB_TGT_R_EXPORT },
132 { "esp", KREG_RSP, MDB_TGT_R_EXPORT | MDB_TGT_R_32 },
133 { "sp", KREG_RSP, MDB_TGT_R_EXPORT | MDB_TGT_R_16 },
134 { "spl", KREG_RSP, MDB_TGT_R_EXPORT | MDB_TGT_R_8L },
135 { "ss", KREG_SS, MDB_TGT_R_EXPORT },
136 { "gsbase", KREG_GSBASE, MDB_TGT_R_EXPORT },
137 { "kgsbase", KREG_KGSBASE, MDB_TGT_R_EXPORT },
138 { "cr2", KREG_CR2, MDB_TGT_R_EXPORT },
139 { "cr3", KREG_CR3, MDB_TGT_R_EXPORT },
140 { NULL, 0, 0 }
141 };
142
143 void
144 mdb_amd64_printregs(const mdb_tgt_gregset_t *gregs)
145 {
146 const kreg_t *kregs = &gregs->kregs[0];
147 kreg_t rflags = kregs[KREG_RFLAGS];
148
149 #define GETREG2(x) ((uintptr_t)kregs[(x)]), ((uintptr_t)kregs[(x)])
150
151 mdb_printf("%%rax = 0x%0?p %15A %%r9 = 0x%0?p %A\n",
152 GETREG2(KREG_RAX), GETREG2(KREG_R9));
153 mdb_printf("%%rbx = 0x%0?p %15A %%r10 = 0x%0?p %A\n",
154 GETREG2(KREG_RBX), GETREG2(KREG_R10));
155 mdb_printf("%%rcx = 0x%0?p %15A %%r11 = 0x%0?p %A\n",
156 GETREG2(KREG_RCX), GETREG2(KREG_R11));
157 mdb_printf("%%rdx = 0x%0?p %15A %%r12 = 0x%0?p %A\n",
158 GETREG2(KREG_RDX), GETREG2(KREG_R12));
159 mdb_printf("%%rsi = 0x%0?p %15A %%r13 = 0x%0?p %A\n",
160 GETREG2(KREG_RSI), GETREG2(KREG_R13));
161 mdb_printf("%%rdi = 0x%0?p %15A %%r14 = 0x%0?p %A\n",
162 GETREG2(KREG_RDI), GETREG2(KREG_R14));
163 mdb_printf("%%r8 = 0x%0?p %15A %%r15 = 0x%0?p %A\n\n",
164 GETREG2(KREG_R8), GETREG2(KREG_R15));
165
166 mdb_printf("%%rip = 0x%0?p %A\n", GETREG2(KREG_RIP));
167 mdb_printf("%%rbp = 0x%0?p\n", kregs[KREG_RBP]);
168 mdb_printf("%%rsp = 0x%0?p\n", kregs[KREG_RSP]);
169
170 mdb_printf("%%rflags = 0x%08x\n", rflags);
171
172 mdb_printf(" id=%u vip=%u vif=%u ac=%u vm=%u rf=%u nt=%u iopl=0x%x\n",
173 (rflags & KREG_EFLAGS_ID_MASK) >> KREG_EFLAGS_ID_SHIFT,
174 (rflags & KREG_EFLAGS_VIP_MASK) >> KREG_EFLAGS_VIP_SHIFT,
175 (rflags & KREG_EFLAGS_VIF_MASK) >> KREG_EFLAGS_VIF_SHIFT,
176 (rflags & KREG_EFLAGS_AC_MASK) >> KREG_EFLAGS_AC_SHIFT,
177 (rflags & KREG_EFLAGS_VM_MASK) >> KREG_EFLAGS_VM_SHIFT,
178 (rflags & KREG_EFLAGS_RF_MASK) >> KREG_EFLAGS_RF_SHIFT,
179 (rflags & KREG_EFLAGS_NT_MASK) >> KREG_EFLAGS_NT_SHIFT,
180 (rflags & KREG_EFLAGS_IOPL_MASK) >> KREG_EFLAGS_IOPL_SHIFT);
181
182 mdb_printf(" status=<%s,%s,%s,%s,%s,%s,%s,%s,%s>\n\n",
183 (rflags & KREG_EFLAGS_OF_MASK) ? "OF" : "of",
184 (rflags & KREG_EFLAGS_DF_MASK) ? "DF" : "df",
185 (rflags & KREG_EFLAGS_IF_MASK) ? "IF" : "if",
186 (rflags & KREG_EFLAGS_TF_MASK) ? "TF" : "tf",
187 (rflags & KREG_EFLAGS_SF_MASK) ? "SF" : "sf",
188 (rflags & KREG_EFLAGS_ZF_MASK) ? "ZF" : "zf",
189 (rflags & KREG_EFLAGS_AF_MASK) ? "AF" : "af",
190 (rflags & KREG_EFLAGS_PF_MASK) ? "PF" : "pf",
191 (rflags & KREG_EFLAGS_CF_MASK) ? "CF" : "cf");
192
193 mdb_printf("%%cs = 0x%04x\t%%ds = 0x%04x\t"
194 "%%es = 0x%04x\t%%fs = 0x%04x\n", kregs[KREG_CS], kregs[KREG_DS],
195 kregs[KREG_ES], kregs[KREG_FS] & 0xffff);
196 mdb_printf("%%gs = 0x%04x\t%%gsbase = 0x%lx\t%%kgsbase = 0x%lx\n",
197 kregs[KREG_GS] & 0xffff, kregs[KREG_GSBASE], kregs[KREG_KGSBASE]);
198 mdb_printf("%%trapno = 0x%x\t%%err = 0x%x\t%%cr2 = 0x%lx\t"
199 "%%cr3 = 0x%lx\n", kregs[KREG_TRAPNO], kregs[KREG_ERR],
200 kregs[KREG_CR2], kregs[KREG_CR3]);
201 }
202
203 int
204 mdb_amd64_kvm_stack_iter(mdb_tgt_t *t, const mdb_tgt_gregset_t *gsp,
205 mdb_tgt_stack_f *func, void *arg)
206 {
207 mdb_tgt_gregset_t gregs;
208 kreg_t *kregs = &gregs.kregs[0];
209 int got_pc = (gsp->kregs[KREG_RIP] != 0);
210 uint_t argc, reg_argc;
211 long fr_argv[32];
212 int start_index; /* index to save_instr where to start comparison */
213 int err;
214 int i;
215
216 struct fr {
217 uintptr_t fr_savfp;
218 uintptr_t fr_savpc;
219 } fr;
220
221 uintptr_t fp = gsp->kregs[KREG_RBP];
222 uintptr_t pc = gsp->kregs[KREG_RIP];
223 uintptr_t lastfp = 0;
224
225 ssize_t size;
226 ssize_t insnsize;
227 uint8_t ins[SAVEARGS_INSN_SEQ_LEN];
228
229 GElf_Sym s;
230 mdb_syminfo_t sip;
231 mdb_ctf_funcinfo_t mfp;
232 int xpv_panic = 0;
233 int advance_tortoise = 1;
234 uintptr_t tortoise_fp = 0;
235 #ifndef _KMDB
236 int xp;
237
238 if ((mdb_readsym(&xp, sizeof (xp), "xpv_panicking") != -1) && (xp > 0))
239 xpv_panic = 1;
240 #endif
241
242 bcopy(gsp, &gregs, sizeof (gregs));
243
244 while (fp != 0) {
245 int args_style = 0;
246
247 if (mdb_tgt_vread(t, &fr, sizeof (fr), fp) != sizeof (fr)) {
248 err = EMDB_NOMAP;
249 goto badfp;
250 }
251
252 if (tortoise_fp == 0) {
253 tortoise_fp = fp;
254 } else {
255 /*
256 * Advance tortoise_fp every other frame, so we detect
257 * cycles with Floyd's tortoise/hare.
258 */
259 if (advance_tortoise != 0) {
260 struct fr tfr;
261
262 if (mdb_tgt_vread(t, &tfr, sizeof (tfr),
263 tortoise_fp) != sizeof (tfr)) {
264 err = EMDB_NOMAP;
265 goto badfp;
266 }
267
268 tortoise_fp = tfr.fr_savfp;
269 }
270
271 if (fp == tortoise_fp) {
272 err = EMDB_STKFRAME;
273 goto badfp;
274 }
275 }
276
277 advance_tortoise = !advance_tortoise;
278
279 if ((mdb_tgt_lookup_by_addr(t, pc, MDB_TGT_SYM_FUZZY,
280 NULL, 0, &s, &sip) == 0) &&
281 (mdb_ctf_func_info(&s, &sip, &mfp) == 0)) {
282 int return_type = mdb_ctf_type_kind(mfp.mtf_return);
283 mdb_ctf_id_t args_types[5];
284
285 argc = mfp.mtf_argc;
286
287 /*
288 * If the function returns a structure or union
289 * greater than 16 bytes in size %rdi contains the
290 * address in which to store the return value rather
291 * than for an argument.
292 */
293 if ((return_type == CTF_K_STRUCT ||
294 return_type == CTF_K_UNION) &&
295 mdb_ctf_type_size(mfp.mtf_return) > 16)
296 start_index = 1;
297 else
298 start_index = 0;
299
300 /*
301 * If any of the first 5 arguments are a structure
302 * less than 16 bytes in size, it will be passed
303 * spread across two argument registers, and we will
304 * not cope.
305 */
306 if (mdb_ctf_func_args(&mfp, 5, args_types) == CTF_ERR)
307 argc = 0;
308
309 for (i = 0; i < MIN(5, argc); i++) {
310 int t = mdb_ctf_type_kind(args_types[i]);
311
312 if (((t == CTF_K_STRUCT) ||
313 (t == CTF_K_UNION)) &&
314 mdb_ctf_type_size(args_types[i]) <= 16) {
315 argc = 0;
316 break;
317 }
318 }
319 } else {
320 argc = 0;
321 }
322
323 /*
324 * The number of instructions to search for argument saving is
325 * limited such that only instructions prior to %pc are
326 * considered such that we never read arguments from a
327 * function where the saving code has not in fact yet
328 * executed.
329 */
330 insnsize = MIN(MIN(s.st_size, SAVEARGS_INSN_SEQ_LEN),
331 pc - s.st_value);
332
333 if (mdb_tgt_vread(t, ins, insnsize, s.st_value) != insnsize)
334 argc = 0;
335
336 if ((argc != 0) &&
337 ((args_style = saveargs_has_args(ins, insnsize, argc,
338 start_index)) != SAVEARGS_NO_ARGS)) {
339 /* Up to 6 arguments are passed via registers */
340 reg_argc = MIN((6 - start_index), mfp.mtf_argc);
341 size = reg_argc * sizeof (long);
342
343 /*
344 * If Studio pushed a structure return address as an
345 * argument, we need to read one more argument than
346 * actually exists (the addr) to make everything line
347 * up.
348 */
349 if (args_style == SAVEARGS_STRUCT_ARGS)
350 size += sizeof (long);
351
352 if (mdb_tgt_vread(t, fr_argv, size, (fp - size))
353 != size)
354 return (-1); /* errno has been set for us */
355
356 /*
357 * Arrange the arguments in the right order for
358 * printing.
359 */
360 for (i = 0; i < (reg_argc / 2); i++) {
361 long t = fr_argv[i];
362
363 fr_argv[i] = fr_argv[reg_argc - i - 1];
364 fr_argv[reg_argc - i - 1] = t;
365 }
366
367 if (argc > reg_argc) {
368 size = MIN((argc - reg_argc) * sizeof (long),
369 sizeof (fr_argv) -
370 (reg_argc * sizeof (long)));
371
372 if (mdb_tgt_vread(t, &fr_argv[reg_argc], size,
373 fp + sizeof (fr)) != size)
374 return (-1); /* errno has been set */
375 }
376 } else {
377 argc = 0;
378 }
379
380 if (got_pc && func(arg, pc, argc, fr_argv, &gregs) != 0)
381 break;
382
383 kregs[KREG_RSP] = kregs[KREG_RBP];
384
385 lastfp = fp;
386 fp = fr.fr_savfp;
387 /*
388 * The Xen hypervisor marks a stack frame as belonging to
389 * an exception by inverting the bits of the pointer to
390 * that frame. We attempt to identify these frames by
391 * inverting the pointer and seeing if it is within 0xfff
392 * bytes of the last frame.
393 */
394 if (xpv_panic)
395 if ((fp != 0) && (fp < lastfp) &&
396 ((lastfp ^ ~fp) < 0xfff))
397 fp = ~fp;
398
399 kregs[KREG_RBP] = fp;
400 kregs[KREG_RIP] = pc = fr.fr_savpc;
401
402 got_pc = (pc != 0);
403 }
404
405 return (0);
406
407 badfp:
408 mdb_printf("%p [%s]", fp, mdb_strerror(err));
409 return (set_errno(err));
410 }
411
412 /*
413 * Determine the return address for the current frame. Typically this is the
414 * fr_savpc value from the current frame, but we also perform some special
415 * handling to see if we are stopped on one of the first two instructions of
416 * a typical function prologue, in which case %rbp will not be set up yet.
417 */
418 int
419 mdb_amd64_step_out(mdb_tgt_t *t, uintptr_t *p, kreg_t pc, kreg_t fp, kreg_t sp,
420 mdb_instr_t curinstr)
421 {
422 struct frame fr;
423 GElf_Sym s;
424 char buf[1];
425
426 enum {
427 M_PUSHQ_RBP = 0x55, /* pushq %rbp */
428 M_REX_W = 0x48, /* REX prefix with only W set */
429 M_MOVL_RBP = 0x8b /* movq %rsp, %rbp with prefix */
430 };
431
432 if (mdb_tgt_lookup_by_addr(t, pc, MDB_TGT_SYM_FUZZY,
433 buf, 0, &s, NULL) == 0) {
434 if (pc == s.st_value && curinstr == M_PUSHQ_RBP)
435 fp = sp - 8;
436 else if (pc == s.st_value + 1 && curinstr == M_REX_W) {
437 if (mdb_tgt_vread(t, &curinstr, sizeof (curinstr),
438 pc + 1) == sizeof (curinstr) && curinstr ==
439 M_MOVL_RBP)
440 fp = sp;
441 }
442 }
443
444 if (mdb_tgt_vread(t, &fr, sizeof (fr), fp) == sizeof (fr)) {
445 *p = fr.fr_savpc;
446 return (0);
447 }
448
449 return (-1); /* errno is set for us */
450 }
451
452 /*ARGSUSED*/
453 int
454 mdb_amd64_next(mdb_tgt_t *t, uintptr_t *p, kreg_t pc, mdb_instr_t curinstr)
455 {
456 mdb_tgt_addr_t npc;
457 mdb_tgt_addr_t callpc;
458
459 enum {
460 M_CALL_REL = 0xe8, /* call near with relative displacement */
461 M_CALL_REG = 0xff, /* call near indirect or call far register */
462
463 M_REX_LO = 0x40,
464 M_REX_HI = 0x4f
465 };
466
467 /*
468 * If the opcode is a near call with relative displacement, assume the
469 * displacement is a rel32 from the next instruction.
470 */
471 if (curinstr == M_CALL_REL) {
472 *p = pc + sizeof (mdb_instr_t) + sizeof (uint32_t);
473 return (0);
474 }
475
476 /* Skip the rex prefix, if any */
477 callpc = pc;
478 while (curinstr >= M_REX_LO && curinstr <= M_REX_HI) {
479 if (mdb_tgt_vread(t, &curinstr, sizeof (curinstr), ++callpc) !=
480 sizeof (curinstr))
481 return (-1); /* errno is set for us */
482 }
483
484 if (curinstr != M_CALL_REG) {
485 /* It's not a call */
486 return (set_errno(EAGAIN));
487 }
488
489 if ((npc = mdb_dis_nextins(mdb.m_disasm, t, MDB_TGT_AS_VIRT, pc)) == pc)
490 return (-1); /* errno is set for us */
491
492 *p = npc;
493 return (0);
494 }
495
496 /*ARGSUSED*/
497 int
498 mdb_amd64_kvm_frame(void *arglim, uintptr_t pc, uint_t argc, const long *argv,
499 const mdb_tgt_gregset_t *gregs)
500 {
501 argc = MIN(argc, (uintptr_t)arglim);
502 mdb_printf("%a(", pc);
503
504 if (argc != 0) {
505 mdb_printf("%lr", *argv++);
506 for (argc--; argc != 0; argc--)
507 mdb_printf(", %lr", *argv++);
508 }
509
510 mdb_printf(")\n");
511 return (0);
512 }
513
514 int
515 mdb_amd64_kvm_framev(void *arglim, uintptr_t pc, uint_t argc, const long *argv,
516 const mdb_tgt_gregset_t *gregs)
517 {
518 /*
519 * Historically adb limited stack trace argument display to a fixed-
520 * size number of arguments since no symbolic debugging info existed.
521 * On amd64 we can detect the true number of saved arguments so only
522 * respect an arglim of zero; otherwise display the entire argv[].
523 */
524 if (arglim == 0)
525 argc = 0;
526
527 mdb_printf("%0?lr %a(", gregs->kregs[KREG_RBP], pc);
528
529 if (argc != 0) {
530 mdb_printf("%lr", *argv++);
531 for (argc--; argc != 0; argc--)
532 mdb_printf(", %lr", *argv++);
533 }
534
535 mdb_printf(")\n");
536 return (0);
537 }