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) 2012, 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 { NULL, 0, 0 }
137 };
138
139 void
140 mdb_amd64_printregs(const mdb_tgt_gregset_t *gregs)
141 {
142 const kreg_t *kregs = &gregs->kregs[0];
143 kreg_t rflags = kregs[KREG_RFLAGS];
144
145 #define GETREG2(x) ((uintptr_t)kregs[(x)]), ((uintptr_t)kregs[(x)])
146
147 mdb_printf("%%rax = 0x%0?p %15A %%r9 = 0x%0?p %A\n",
148 GETREG2(KREG_RAX), GETREG2(KREG_R9));
149 mdb_printf("%%rbx = 0x%0?p %15A %%r10 = 0x%0?p %A\n",
150 GETREG2(KREG_RBX), GETREG2(KREG_R10));
151 mdb_printf("%%rcx = 0x%0?p %15A %%r11 = 0x%0?p %A\n",
152 GETREG2(KREG_RCX), GETREG2(KREG_R11));
153 mdb_printf("%%rdx = 0x%0?p %15A %%r12 = 0x%0?p %A\n",
154 GETREG2(KREG_RDX), GETREG2(KREG_R12));
155 mdb_printf("%%rsi = 0x%0?p %15A %%r13 = 0x%0?p %A\n",
156 GETREG2(KREG_RSI), GETREG2(KREG_R13));
157 mdb_printf("%%rdi = 0x%0?p %15A %%r14 = 0x%0?p %A\n",
158 GETREG2(KREG_RDI), GETREG2(KREG_R14));
159 mdb_printf("%%r8 = 0x%0?p %15A %%r15 = 0x%0?p %A\n\n",
160 GETREG2(KREG_R8), GETREG2(KREG_R15));
161
162 mdb_printf("%%rip = 0x%0?p %A\n", GETREG2(KREG_RIP));
163 mdb_printf("%%rbp = 0x%0?p\n", kregs[KREG_RBP]);
164 mdb_printf("%%rsp = 0x%0?p\n", kregs[KREG_RSP]);
165
166 mdb_printf("%%rflags = 0x%08x\n", rflags);
167
168 mdb_printf(" id=%u vip=%u vif=%u ac=%u vm=%u rf=%u nt=%u iopl=0x%x\n",
169 (rflags & KREG_EFLAGS_ID_MASK) >> KREG_EFLAGS_ID_SHIFT,
170 (rflags & KREG_EFLAGS_VIP_MASK) >> KREG_EFLAGS_VIP_SHIFT,
171 (rflags & KREG_EFLAGS_VIF_MASK) >> KREG_EFLAGS_VIF_SHIFT,
172 (rflags & KREG_EFLAGS_AC_MASK) >> KREG_EFLAGS_AC_SHIFT,
173 (rflags & KREG_EFLAGS_VM_MASK) >> KREG_EFLAGS_VM_SHIFT,
174 (rflags & KREG_EFLAGS_RF_MASK) >> KREG_EFLAGS_RF_SHIFT,
175 (rflags & KREG_EFLAGS_NT_MASK) >> KREG_EFLAGS_NT_SHIFT,
176 (rflags & KREG_EFLAGS_IOPL_MASK) >> KREG_EFLAGS_IOPL_SHIFT);
177
178 mdb_printf(" status=<%s,%s,%s,%s,%s,%s,%s,%s,%s>\n\n",
179 (rflags & KREG_EFLAGS_OF_MASK) ? "OF" : "of",
180 (rflags & KREG_EFLAGS_DF_MASK) ? "DF" : "df",
181 (rflags & KREG_EFLAGS_IF_MASK) ? "IF" : "if",
182 (rflags & KREG_EFLAGS_TF_MASK) ? "TF" : "tf",
183 (rflags & KREG_EFLAGS_SF_MASK) ? "SF" : "sf",
184 (rflags & KREG_EFLAGS_ZF_MASK) ? "ZF" : "zf",
185 (rflags & KREG_EFLAGS_AF_MASK) ? "AF" : "af",
186 (rflags & KREG_EFLAGS_PF_MASK) ? "PF" : "pf",
187 (rflags & KREG_EFLAGS_CF_MASK) ? "CF" : "cf");
188
189 mdb_printf("%24s%%cs = 0x%04x\t%%ds = 0x%04x\t%%es = 0x%04x\n",
190 " ", kregs[KREG_CS], kregs[KREG_DS], kregs[KREG_ES]);
191
192 mdb_printf("%%trapno = 0x%x\t\t%%fs = 0x%04x\t%%gs = 0x%04x\n",
193 kregs[KREG_TRAPNO], (kregs[KREG_FS] & 0xffff),
194 (kregs[KREG_GS] & 0xffff));
195 mdb_printf(" %%err = 0x%x\n", kregs[KREG_ERR]);
196 }
197
198 int
199 mdb_amd64_kvm_stack_iter(mdb_tgt_t *t, const mdb_tgt_gregset_t *gsp,
200 mdb_tgt_stack_f *func, void *arg)
201 {
202 mdb_tgt_gregset_t gregs;
203 kreg_t *kregs = &gregs.kregs[0];
204 int got_pc = (gsp->kregs[KREG_RIP] != 0);
205 uint_t argc, reg_argc;
206 long fr_argv[32];
207 int start_index; /* index to save_instr where to start comparison */
208 int err;
209 int i;
210
211 struct {
212 uintptr_t fr_savfp;
213 uintptr_t fr_savpc;
214 } fr;
215
216 uintptr_t fp = gsp->kregs[KREG_RBP];
217 uintptr_t pc = gsp->kregs[KREG_RIP];
218 uintptr_t lastfp = 0;
219
220 ssize_t size;
221 ssize_t insnsize;
222 uint8_t ins[SAVEARGS_INSN_SEQ_LEN];
223
224 GElf_Sym s;
225 mdb_syminfo_t sip;
226 mdb_ctf_funcinfo_t mfp;
227 int xpv_panic = 0;
228 #ifndef _KMDB
229 int xp;
230
231 if ((mdb_readsym(&xp, sizeof (xp), "xpv_panicking") != -1) && (xp > 0))
232 xpv_panic = 1;
233 #endif
234
235 bcopy(gsp, &gregs, sizeof (gregs));
236
237 while (fp != 0) {
238 int args_style = 0;
239
240 /*
241 * Ensure progress (increasing fp), and prevent
242 * endless loop with the same FP.
243 */
244 if (fp <= lastfp) {
245 err = EMDB_STKFRAME;
246 goto badfp;
247 }
248 if (mdb_tgt_vread(t, &fr, sizeof (fr), fp) != sizeof (fr)) {
249 err = EMDB_NOMAP;
250 goto badfp;
251 }
252
253 if ((mdb_tgt_lookup_by_addr(t, pc, MDB_TGT_SYM_FUZZY,
254 NULL, 0, &s, &sip) == 0) &&
255 (mdb_ctf_func_info(&s, &sip, &mfp) == 0)) {
256 int return_type = mdb_ctf_type_kind(mfp.mtf_return);
257 mdb_ctf_id_t args_types[5];
258
259 argc = mfp.mtf_argc;
260
261 /*
262 * If the function returns a structure or union
263 * greater than 16 bytes in size %rdi contains the
264 * address in which to store the return value rather
265 * than for an argument.
266 */
267 if ((return_type == CTF_K_STRUCT ||
268 return_type == CTF_K_UNION) &&
269 mdb_ctf_type_size(mfp.mtf_return) > 16)
270 start_index = 1;
271 else
272 start_index = 0;
273
274 /*
275 * If any of the first 5 arguments are a structure
276 * less than 16 bytes in size, it will be passed
277 * spread across two argument registers, and we will
278 * not cope.
279 */
280 if (mdb_ctf_func_args(&mfp, 5, args_types) == CTF_ERR)
281 argc = 0;
282
283 for (i = 0; i < MIN(5, argc); i++) {
284 int t = mdb_ctf_type_kind(args_types[i]);
285
286 if (((t == CTF_K_STRUCT) ||
287 (t == CTF_K_UNION)) &&
288 mdb_ctf_type_size(args_types[i]) <= 16) {
289 argc = 0;
290 break;
291 }
292 }
293 } else {
294 argc = 0;
295 }
296
297 /*
298 * The number of instructions to search for argument saving is
299 * limited such that only instructions prior to %pc are
300 * considered such that we never read arguments from a
301 * function where the saving code has not in fact yet
302 * executed.
303 */
304 insnsize = MIN(MIN(s.st_size, SAVEARGS_INSN_SEQ_LEN),
305 pc - s.st_value);
306
307 if (mdb_tgt_vread(t, ins, insnsize, s.st_value) != insnsize)
308 argc = 0;
309
310 if ((argc != 0) &&
311 ((args_style = saveargs_has_args(ins, insnsize, argc,
312 start_index)) != SAVEARGS_NO_ARGS)) {
313 /* Up to 6 arguments are passed via registers */
314 reg_argc = MIN((6 - start_index), mfp.mtf_argc);
315 size = reg_argc * sizeof (long);
316
317 /*
318 * If Studio pushed a structure return address as an
319 * argument, we need to read one more argument than
320 * actually exists (the addr) to make everything line
321 * up.
322 */
323 if (args_style == SAVEARGS_STRUCT_ARGS)
324 size += sizeof (long);
325
326 if (mdb_tgt_vread(t, fr_argv, size, (fp - size))
327 != size)
328 return (-1); /* errno has been set for us */
329
330 /*
331 * Arrange the arguments in the right order for
332 * printing.
333 */
334 for (i = 0; i < (reg_argc / 2); i++) {
335 long t = fr_argv[i];
336
337 fr_argv[i] = fr_argv[reg_argc - i - 1];
338 fr_argv[reg_argc - i - 1] = t;
339 }
340
341 if (argc > reg_argc) {
342 size = MIN((argc - reg_argc) * sizeof (long),
343 sizeof (fr_argv) -
344 (reg_argc * sizeof (long)));
345
346 if (mdb_tgt_vread(t, &fr_argv[reg_argc], size,
347 fp + sizeof (fr)) != size)
348 return (-1); /* errno has been set */
349 }
350 } else {
351 argc = 0;
352 }
353
354 if (got_pc && func(arg, pc, argc, fr_argv, &gregs) != 0)
355 break;
356
357 kregs[KREG_RSP] = kregs[KREG_RBP];
358
359 lastfp = fp;
360 fp = fr.fr_savfp;
361 /*
362 * The Xen hypervisor marks a stack frame as belonging to
363 * an exception by inverting the bits of the pointer to
364 * that frame. We attempt to identify these frames by
365 * inverting the pointer and seeing if it is within 0xfff
366 * bytes of the last frame.
367 */
368 if (xpv_panic)
369 if ((fp != 0) && (fp < lastfp) &&
370 ((lastfp ^ ~fp) < 0xfff))
371 fp = ~fp;
372
373 kregs[KREG_RBP] = fp;
374 kregs[KREG_RIP] = pc = fr.fr_savpc;
375
376 got_pc = (pc != 0);
377 }
378
379 return (0);
380
381 badfp:
382 mdb_printf("%p [%s]", fp, mdb_strerror(err));
383 return (set_errno(err));
384 }
385
386 /*
387 * Determine the return address for the current frame. Typically this is the
388 * fr_savpc value from the current frame, but we also perform some special
389 * handling to see if we are stopped on one of the first two instructions of
390 * a typical function prologue, in which case %rbp will not be set up yet.
391 */
392 int
393 mdb_amd64_step_out(mdb_tgt_t *t, uintptr_t *p, kreg_t pc, kreg_t fp, kreg_t sp,
394 mdb_instr_t curinstr)
395 {
396 struct frame fr;
397 GElf_Sym s;
398 char buf[1];
399
400 enum {
401 M_PUSHQ_RBP = 0x55, /* pushq %rbp */
402 M_REX_W = 0x48, /* REX prefix with only W set */
403 M_MOVL_RBP = 0x8b /* movq %rsp, %rbp with prefix */
404 };
405
406 if (mdb_tgt_lookup_by_addr(t, pc, MDB_TGT_SYM_FUZZY,
407 buf, 0, &s, NULL) == 0) {
408 if (pc == s.st_value && curinstr == M_PUSHQ_RBP)
409 fp = sp - 8;
410 else if (pc == s.st_value + 1 && curinstr == M_REX_W) {
411 if (mdb_tgt_vread(t, &curinstr, sizeof (curinstr),
412 pc + 1) == sizeof (curinstr) && curinstr ==
413 M_MOVL_RBP)
414 fp = sp;
415 }
416 }
417
418 if (mdb_tgt_vread(t, &fr, sizeof (fr), fp) == sizeof (fr)) {
419 *p = fr.fr_savpc;
420 return (0);
421 }
422
423 return (-1); /* errno is set for us */
424 }
425
426 /*ARGSUSED*/
427 int
428 mdb_amd64_next(mdb_tgt_t *t, uintptr_t *p, kreg_t pc, mdb_instr_t curinstr)
429 {
430 mdb_tgt_addr_t npc;
431 mdb_tgt_addr_t callpc;
432
433 enum {
434 M_CALL_REL = 0xe8, /* call near with relative displacement */
435 M_CALL_REG = 0xff, /* call near indirect or call far register */
436
437 M_REX_LO = 0x40,
438 M_REX_HI = 0x4f
439 };
440
441 /*
442 * If the opcode is a near call with relative displacement, assume the
443 * displacement is a rel32 from the next instruction.
444 */
445 if (curinstr == M_CALL_REL) {
446 *p = pc + sizeof (mdb_instr_t) + sizeof (uint32_t);
447 return (0);
448 }
449
450 /* Skip the rex prefix, if any */
451 callpc = pc;
452 while (curinstr >= M_REX_LO && curinstr <= M_REX_HI) {
453 if (mdb_tgt_vread(t, &curinstr, sizeof (curinstr), ++callpc) !=
454 sizeof (curinstr))
455 return (-1); /* errno is set for us */
456 }
457
458 if (curinstr != M_CALL_REG) {
459 /* It's not a call */
460 return (set_errno(EAGAIN));
461 }
462
463 if ((npc = mdb_dis_nextins(mdb.m_disasm, t, MDB_TGT_AS_VIRT, pc)) == pc)
464 return (-1); /* errno is set for us */
465
466 *p = npc;
467 return (0);
468 }
469
470 /*ARGSUSED*/
471 int
472 mdb_amd64_kvm_frame(void *arglim, uintptr_t pc, uint_t argc, const long *argv,
473 const mdb_tgt_gregset_t *gregs)
474 {
475 argc = MIN(argc, (uintptr_t)arglim);
476 mdb_printf("%a(", pc);
477
478 if (argc != 0) {
479 mdb_printf("%lr", *argv++);
480 for (argc--; argc != 0; argc--)
481 mdb_printf(", %lr", *argv++);
482 }
483
484 mdb_printf(")\n");
485 return (0);
486 }
487
488 int
489 mdb_amd64_kvm_framev(void *arglim, uintptr_t pc, uint_t argc, const long *argv,
490 const mdb_tgt_gregset_t *gregs)
491 {
492 /*
493 * Historically adb limited stack trace argument display to a fixed-
494 * size number of arguments since no symbolic debugging info existed.
495 * On amd64 we can detect the true number of saved arguments so only
496 * respect an arglim of zero; otherwise display the entire argv[].
497 */
498 if (arglim == 0)
499 argc = 0;
500
501 mdb_printf("%0?lr %a(", gregs->kregs[KREG_RBP], pc);
502
503 if (argc != 0) {
504 mdb_printf("%lr", *argv++);
505 for (argc--; argc != 0; argc--)
506 mdb_printf(", %lr", *argv++);
507 }
508
509 mdb_printf(")\n");
510 return (0);
511 }