xref: /titanic_41/usr/src/cmd/mdb/i86pc/modules/unix/unix.c (revision fd9ee8b58485b20072eeef1310a88ff348d5e7fa)
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 (c) 1999, 2010, Oracle and/or its affiliates. All rights reserved.
23  */
24 
25 #include <mdb/mdb_modapi.h>
26 #include <mdb/mdb_ctf.h>
27 #include <sys/cpuvar.h>
28 #include <sys/systm.h>
29 #include <sys/traptrace.h>
30 #include <sys/x_call.h>
31 #include <sys/xc_levels.h>
32 #include <sys/avintr.h>
33 #include <sys/systm.h>
34 #include <sys/trap.h>
35 #include <sys/mutex.h>
36 #include <sys/mutex_impl.h>
37 #include "i86mmu.h"
38 #include <sys/apix.h>
39 
40 #define	TT_HDLR_WIDTH	17
41 
42 
43 /* apix only */
44 static apix_impl_t *d_apixs[NCPU];
45 static int use_apix = 0;
46 
47 static int
48 ttrace_ttr_size_check(void)
49 {
50 	mdb_ctf_id_t ttrtid;
51 	ssize_t ttr_size;
52 
53 	if (mdb_ctf_lookup_by_name("trap_trace_rec_t", &ttrtid) != 0 ||
54 	    mdb_ctf_type_resolve(ttrtid, &ttrtid) != 0) {
55 		mdb_warn("failed to determine size of trap_trace_rec_t; "
56 		    "non-TRAPTRACE kernel?\n");
57 		return (0);
58 	}
59 
60 	if ((ttr_size = mdb_ctf_type_size(ttrtid)) !=
61 	    sizeof (trap_trace_rec_t)) {
62 		/*
63 		 * On Intel machines, this will happen when TTR_STACK_DEPTH
64 		 * is changed.  This code could be smarter, and could
65 		 * dynamically adapt to different depths, but not until a
66 		 * need for such adaptation is demonstrated.
67 		 */
68 		mdb_warn("size of trap_trace_rec_t (%d bytes) doesn't "
69 		    "match expected %d\n", ttr_size, sizeof (trap_trace_rec_t));
70 		return (0);
71 	}
72 
73 	return (1);
74 }
75 
76 int
77 ttrace_walk_init(mdb_walk_state_t *wsp)
78 {
79 	trap_trace_ctl_t *ttcp;
80 	size_t ttc_size = sizeof (trap_trace_ctl_t) * NCPU;
81 	int i;
82 
83 	if (!ttrace_ttr_size_check())
84 		return (WALK_ERR);
85 
86 	ttcp = mdb_zalloc(ttc_size, UM_SLEEP);
87 
88 	if (wsp->walk_addr != NULL) {
89 		mdb_warn("ttrace only supports global walks\n");
90 		return (WALK_ERR);
91 	}
92 
93 	if (mdb_readsym(ttcp, ttc_size, "trap_trace_ctl") == -1) {
94 		mdb_warn("symbol 'trap_trace_ctl' not found; "
95 		    "non-TRAPTRACE kernel?\n");
96 		mdb_free(ttcp, ttc_size);
97 		return (WALK_ERR);
98 	}
99 
100 	/*
101 	 * We'll poach the ttc_current pointer (which isn't used for
102 	 * anything) to store a pointer to our current TRAPTRACE record.
103 	 * This allows us to only keep the array of trap_trace_ctl structures
104 	 * as our walker state (ttc_current may be the only kernel data
105 	 * structure member added exclusively to make writing the mdb walker
106 	 * a little easier).
107 	 */
108 	for (i = 0; i < NCPU; i++) {
109 		trap_trace_ctl_t *ttc = &ttcp[i];
110 
111 		if (ttc->ttc_first == NULL)
112 			continue;
113 
114 		/*
115 		 * Assign ttc_current to be the last completed record.
116 		 * Note that the error checking (i.e. in the ttc_next ==
117 		 * ttc_first case) is performed in the step function.
118 		 */
119 		ttc->ttc_current = ttc->ttc_next - sizeof (trap_trace_rec_t);
120 	}
121 
122 	wsp->walk_data = ttcp;
123 	return (WALK_NEXT);
124 }
125 
126 int
127 ttrace_walk_step(mdb_walk_state_t *wsp)
128 {
129 	trap_trace_ctl_t *ttcp = wsp->walk_data, *ttc, *latest_ttc;
130 	trap_trace_rec_t rec;
131 	int rval, i, recsize = sizeof (trap_trace_rec_t);
132 	hrtime_t latest = 0;
133 
134 	/*
135 	 * Loop through the CPUs, looking for the latest trap trace record
136 	 * (we want to walk through the trap trace records in reverse
137 	 * chronological order).
138 	 */
139 	for (i = 0; i < NCPU; i++) {
140 		ttc = &ttcp[i];
141 
142 		if (ttc->ttc_current == NULL)
143 			continue;
144 
145 		if (ttc->ttc_current < ttc->ttc_first)
146 			ttc->ttc_current = ttc->ttc_limit - recsize;
147 
148 		if (mdb_vread(&rec, sizeof (rec), ttc->ttc_current) == -1) {
149 			mdb_warn("couldn't read rec at %p", ttc->ttc_current);
150 			return (WALK_ERR);
151 		}
152 
153 		if (rec.ttr_stamp > latest) {
154 			latest = rec.ttr_stamp;
155 			latest_ttc = ttc;
156 		}
157 	}
158 
159 	if (latest == 0)
160 		return (WALK_DONE);
161 
162 	ttc = latest_ttc;
163 
164 	if (mdb_vread(&rec, sizeof (rec), ttc->ttc_current) == -1) {
165 		mdb_warn("couldn't read rec at %p", ttc->ttc_current);
166 		return (WALK_ERR);
167 	}
168 
169 	rval = wsp->walk_callback(ttc->ttc_current, &rec, wsp->walk_cbdata);
170 
171 	if (ttc->ttc_current == ttc->ttc_next)
172 		ttc->ttc_current = NULL;
173 	else
174 		ttc->ttc_current -= sizeof (trap_trace_rec_t);
175 
176 	return (rval);
177 }
178 
179 void
180 ttrace_walk_fini(mdb_walk_state_t *wsp)
181 {
182 	mdb_free(wsp->walk_data, sizeof (trap_trace_ctl_t) * NCPU);
183 }
184 
185 static int
186 ttrace_syscall(trap_trace_rec_t *rec)
187 {
188 	GElf_Sym sym;
189 	int sysnum = rec->ttr_sysnum;
190 	uintptr_t addr;
191 	struct sysent sys;
192 
193 	mdb_printf("%-3x", sysnum);
194 
195 	if (rec->ttr_sysnum > NSYSCALL) {
196 		mdb_printf(" %-*d", TT_HDLR_WIDTH, rec->ttr_sysnum);
197 		return (0);
198 	}
199 
200 	if (mdb_lookup_by_name("sysent", &sym) == -1) {
201 		mdb_warn("\ncouldn't find 'sysent'");
202 		return (-1);
203 	}
204 
205 	addr = (uintptr_t)sym.st_value + sysnum * sizeof (struct sysent);
206 
207 	if (addr >= (uintptr_t)sym.st_value + sym.st_size) {
208 		mdb_warn("\nsysnum %d out-of-range\n", sysnum);
209 		return (-1);
210 	}
211 
212 	if (mdb_vread(&sys, sizeof (sys), addr) == -1) {
213 		mdb_warn("\nfailed to read sysent at %p", addr);
214 		return (-1);
215 	}
216 
217 	mdb_printf(" %-*a", TT_HDLR_WIDTH, sys.sy_callc);
218 
219 	return (0);
220 }
221 
222 static int
223 ttrace_interrupt(trap_trace_rec_t *rec)
224 {
225 	GElf_Sym sym;
226 	uintptr_t addr;
227 	struct av_head hd;
228 	struct autovec av;
229 
230 	switch (rec->ttr_regs.r_trapno) {
231 	case T_SOFTINT:
232 		mdb_printf("%-3s %-*s", "-", TT_HDLR_WIDTH, "(fakesoftint)");
233 		return (0);
234 	default:
235 		break;
236 	}
237 
238 	mdb_printf("%-3x ", rec->ttr_vector);
239 
240 	if (mdb_lookup_by_name("autovect", &sym) == -1) {
241 		mdb_warn("\ncouldn't find 'autovect'");
242 		return (-1);
243 	}
244 
245 	addr = (uintptr_t)sym.st_value +
246 	    rec->ttr_vector * sizeof (struct av_head);
247 
248 	if (addr >= (uintptr_t)sym.st_value + sym.st_size) {
249 		mdb_warn("\nav_head for vec %x is corrupt\n", rec->ttr_vector);
250 		return (-1);
251 	}
252 
253 	if (mdb_vread(&hd, sizeof (hd), addr) == -1) {
254 		mdb_warn("\ncouldn't read av_head for vec %x", rec->ttr_vector);
255 		return (-1);
256 	}
257 
258 	if (hd.avh_link == NULL) {
259 		if (rec->ttr_ipl == XC_CPUPOKE_PIL)
260 			mdb_printf("%-*s", TT_HDLR_WIDTH, "(cpupoke)");
261 		else
262 			mdb_printf("%-*s", TT_HDLR_WIDTH, "(spurious)");
263 	} else {
264 		if (mdb_vread(&av, sizeof (av), (uintptr_t)hd.avh_link) == -1) {
265 			mdb_warn("couldn't read autovec at %p",
266 			    (uintptr_t)hd.avh_link);
267 		}
268 
269 		mdb_printf("%-*a", TT_HDLR_WIDTH, av.av_vector);
270 	}
271 
272 	return (0);
273 }
274 
275 static int
276 ttrace_apix_interrupt(trap_trace_rec_t *rec)
277 {
278 	struct autovec av;
279 	apix_impl_t apix;
280 	apix_vector_t apix_vector;
281 
282 	switch (rec->ttr_regs.r_trapno) {
283 	case T_SOFTINT:
284 		mdb_printf("%-3s %-*s", "-", TT_HDLR_WIDTH, "(fakesoftint)");
285 		return (0);
286 	default:
287 		break;
288 	}
289 
290 	mdb_printf("%-3x ", rec->ttr_vector);
291 
292 	/* Read the per CPU apix entry */
293 	if (mdb_vread(&apix, sizeof (apix_impl_t),
294 	    (uintptr_t)d_apixs[rec->ttr_cpuid]) == -1) {
295 		mdb_warn("\ncouldn't read apix[%d]", rec->ttr_cpuid);
296 		return (-1);
297 	}
298 	if (mdb_vread(&apix_vector, sizeof (apix_vector_t),
299 	    (uintptr_t)apix.x_vectbl[rec->ttr_vector]) == -1) {
300 		mdb_warn("\ncouldn't read apix_vector_t[%d]", rec->ttr_vector);
301 		return (-1);
302 	}
303 	if (apix_vector.v_share == 0) {
304 		if (rec->ttr_ipl == XC_CPUPOKE_PIL)
305 			mdb_printf("%-*s", TT_HDLR_WIDTH, "(cpupoke)");
306 		else
307 			mdb_printf("%-*s", TT_HDLR_WIDTH, "(spurious)");
308 	} else {
309 		if (mdb_vread(&av, sizeof (struct autovec),
310 		    (uintptr_t)(apix_vector.v_autovect)) == -1) {
311 			mdb_warn("couldn't read autovec at %p",
312 			    (uintptr_t)apix_vector.v_autovect);
313 		}
314 
315 		mdb_printf("%-*a", TT_HDLR_WIDTH, av.av_vector);
316 	}
317 
318 	return (0);
319 }
320 
321 
322 static struct {
323 	int tt_trapno;
324 	char *tt_name;
325 } ttrace_traps[] = {
326 	{ T_ZERODIV,	"divide-error" },
327 	{ T_SGLSTP,	"debug-exception" },
328 	{ T_NMIFLT,	"nmi-interrupt" },
329 	{ T_BPTFLT,	"breakpoint" },
330 	{ T_OVFLW,	"into-overflow" },
331 	{ T_BOUNDFLT,	"bound-exceeded" },
332 	{ T_ILLINST,	"invalid-opcode" },
333 	{ T_NOEXTFLT,	"device-not-avail" },
334 	{ T_DBLFLT,	"double-fault" },
335 	{ T_EXTOVRFLT,	"segment-overrun" },
336 	{ T_TSSFLT,	"invalid-tss" },
337 	{ T_SEGFLT,	"segment-not-pres" },
338 	{ T_STKFLT,	"stack-fault" },
339 	{ T_GPFLT,	"general-protectn" },
340 	{ T_PGFLT,	"page-fault" },
341 	{ T_EXTERRFLT,	"error-fault" },
342 	{ T_ALIGNMENT,	"alignment-check" },
343 	{ T_MCE,	"machine-check" },
344 	{ T_SIMDFPE,	"sse-exception" },
345 
346 	{ T_DBGENTR,	"debug-enter" },
347 	{ T_FASTTRAP,	"fasttrap-0xd2" },
348 	{ T_SYSCALLINT,	"syscall-0x91" },
349 	{ T_DTRACE_RET,	"dtrace-ret" },
350 	{ T_SOFTINT,	"softint" },
351 	{ T_INTERRUPT,	"interrupt" },
352 	{ T_FAULT,	"fault" },
353 	{ T_AST,	"ast" },
354 	{ T_SYSCALL,	"syscall" },
355 
356 	{ 0,		NULL }
357 };
358 
359 static int
360 ttrace_trap(trap_trace_rec_t *rec)
361 {
362 	int i;
363 
364 	if (rec->ttr_regs.r_trapno == T_AST)
365 		mdb_printf("%-3s ", "-");
366 	else
367 		mdb_printf("%-3x ", rec->ttr_regs.r_trapno);
368 
369 	for (i = 0; ttrace_traps[i].tt_name != NULL; i++) {
370 		if (rec->ttr_regs.r_trapno == ttrace_traps[i].tt_trapno)
371 			break;
372 	}
373 
374 	if (ttrace_traps[i].tt_name == NULL)
375 		mdb_printf("%-*s", TT_HDLR_WIDTH, "(unknown)");
376 	else
377 		mdb_printf("%-*s", TT_HDLR_WIDTH, ttrace_traps[i].tt_name);
378 
379 	return (0);
380 }
381 
382 static void
383 ttrace_intr_detail(trap_trace_rec_t *rec)
384 {
385 	mdb_printf("\tirq %x ipl %d oldpri %d basepri %d\n", rec->ttr_vector,
386 	    rec->ttr_ipl, rec->ttr_pri, rec->ttr_spl);
387 }
388 
389 static struct {
390 	uchar_t t_marker;
391 	char *t_name;
392 	int (*t_hdlr)(trap_trace_rec_t *);
393 } ttrace_hdlr[] = {
394 	{ TT_SYSCALL, "sysc", ttrace_syscall },
395 	{ TT_SYSENTER, "syse", ttrace_syscall },
396 	{ TT_SYSC, "asys", ttrace_syscall },
397 	{ TT_SYSC64, "sc64", ttrace_syscall },
398 	{ TT_INTERRUPT, "intr", ttrace_interrupt },
399 	{ TT_TRAP, "trap", ttrace_trap },
400 	{ TT_EVENT, "evnt", ttrace_trap },
401 	{ 0, NULL, NULL }
402 };
403 
404 typedef struct ttrace_dcmd {
405 	processorid_t ttd_cpu;
406 	uint_t ttd_extended;
407 	trap_trace_ctl_t ttd_ttc[NCPU];
408 } ttrace_dcmd_t;
409 
410 #if defined(__amd64)
411 
412 #define	DUMP(reg) #reg, regs->r_##reg
413 #define	THREEREGS	"         %3s: %16lx %3s: %16lx %3s: %16lx\n"
414 
415 static void
416 ttrace_dumpregs(trap_trace_rec_t *rec)
417 {
418 	struct regs *regs = &rec->ttr_regs;
419 
420 	mdb_printf(THREEREGS, DUMP(rdi), DUMP(rsi), DUMP(rdx));
421 	mdb_printf(THREEREGS, DUMP(rcx), DUMP(r8), DUMP(r9));
422 	mdb_printf(THREEREGS, DUMP(rax), DUMP(rbx), DUMP(rbp));
423 	mdb_printf(THREEREGS, DUMP(r10), DUMP(r11), DUMP(r12));
424 	mdb_printf(THREEREGS, DUMP(r13), DUMP(r14), DUMP(r15));
425 	mdb_printf(THREEREGS, DUMP(ds), DUMP(es), DUMP(fs));
426 	mdb_printf(THREEREGS, DUMP(gs), "trp", regs->r_trapno, DUMP(err));
427 	mdb_printf(THREEREGS, DUMP(rip), DUMP(cs), DUMP(rfl));
428 	mdb_printf(THREEREGS, DUMP(rsp), DUMP(ss), "cr2", rec->ttr_cr2);
429 	mdb_printf("\n");
430 }
431 
432 #else
433 
434 #define	DUMP(reg) #reg, regs->r_##reg
435 #define	FOURREGS	"         %3s: %08x %3s: %08x %3s: %08x %3s: %08x\n"
436 
437 static void
438 ttrace_dumpregs(trap_trace_rec_t *rec)
439 {
440 	struct regs *regs = &rec->ttr_regs;
441 
442 	mdb_printf(FOURREGS, DUMP(gs), DUMP(fs), DUMP(es), DUMP(ds));
443 	mdb_printf(FOURREGS, DUMP(edi), DUMP(esi), DUMP(ebp), DUMP(esp));
444 	mdb_printf(FOURREGS, DUMP(ebx), DUMP(edx), DUMP(ecx), DUMP(eax));
445 	mdb_printf(FOURREGS, "trp", regs->r_trapno, DUMP(err),
446 	    DUMP(pc), DUMP(cs));
447 	mdb_printf(FOURREGS, DUMP(efl), "usp", regs->r_uesp, DUMP(ss),
448 	    "cr2", rec->ttr_cr2);
449 	mdb_printf("\n");
450 }
451 
452 #endif	/* __amd64 */
453 
454 int
455 ttrace_walk(uintptr_t addr, trap_trace_rec_t *rec, ttrace_dcmd_t *dcmd)
456 {
457 	struct regs *regs = &rec->ttr_regs;
458 	processorid_t cpu = -1, i;
459 
460 	for (i = 0; i < NCPU; i++) {
461 		if (addr >= dcmd->ttd_ttc[i].ttc_first &&
462 		    addr < dcmd->ttd_ttc[i].ttc_limit) {
463 			cpu = i;
464 			break;
465 		}
466 	}
467 
468 	if (cpu == -1) {
469 		mdb_warn("couldn't find %p in any trap trace ctl\n", addr);
470 		return (WALK_ERR);
471 	}
472 
473 	if (dcmd->ttd_cpu != -1 && cpu != dcmd->ttd_cpu)
474 		return (WALK_NEXT);
475 
476 	mdb_printf("%3d %15llx ", cpu, rec->ttr_stamp);
477 
478 	for (i = 0; ttrace_hdlr[i].t_hdlr != NULL; i++) {
479 		if (rec->ttr_marker != ttrace_hdlr[i].t_marker)
480 			continue;
481 		mdb_printf("%4s ", ttrace_hdlr[i].t_name);
482 		if (ttrace_hdlr[i].t_hdlr(rec) == -1)
483 			return (WALK_ERR);
484 	}
485 
486 	mdb_printf(" %a\n", regs->r_pc);
487 
488 	if (dcmd->ttd_extended == FALSE)
489 		return (WALK_NEXT);
490 
491 	if (rec->ttr_marker == TT_INTERRUPT)
492 		ttrace_intr_detail(rec);
493 	else
494 		ttrace_dumpregs(rec);
495 
496 	if (rec->ttr_sdepth > 0) {
497 		for (i = 0; i < rec->ttr_sdepth; i++) {
498 			if (i >= TTR_STACK_DEPTH) {
499 				mdb_printf("%17s*** invalid ttr_sdepth (is %d, "
500 				    "should be <= %d)\n", " ", rec->ttr_sdepth,
501 				    TTR_STACK_DEPTH);
502 				break;
503 			}
504 
505 			mdb_printf("%17s %a()\n", " ", rec->ttr_stack[i]);
506 		}
507 		mdb_printf("\n");
508 	}
509 
510 	return (WALK_NEXT);
511 }
512 
513 int
514 ttrace(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
515 {
516 	ttrace_dcmd_t dcmd;
517 	trap_trace_ctl_t *ttc = dcmd.ttd_ttc;
518 	trap_trace_rec_t rec;
519 	size_t ttc_size = sizeof (trap_trace_ctl_t) * NCPU;
520 
521 	if (!ttrace_ttr_size_check())
522 		return (WALK_ERR);
523 
524 	bzero(&dcmd, sizeof (dcmd));
525 	dcmd.ttd_cpu = -1;
526 	dcmd.ttd_extended = FALSE;
527 
528 	if (mdb_readsym(ttc, ttc_size, "trap_trace_ctl") == -1) {
529 		mdb_warn("symbol 'trap_trace_ctl' not found; "
530 		    "non-TRAPTRACE kernel?\n");
531 		return (DCMD_ERR);
532 	}
533 
534 	if (mdb_getopts(argc, argv,
535 	    'x', MDB_OPT_SETBITS, TRUE, &dcmd.ttd_extended, NULL) != argc)
536 		return (DCMD_USAGE);
537 
538 	if (DCMD_HDRSPEC(flags)) {
539 		mdb_printf("%3s %15s %4s %2s %-*s%s\n", "CPU",
540 		    "TIMESTAMP", "TYPE", "Vec", TT_HDLR_WIDTH, "HANDLER",
541 		    " EIP");
542 	}
543 
544 	if (flags & DCMD_ADDRSPEC) {
545 		if (addr >= NCPU) {
546 			if (mdb_vread(&rec, sizeof (rec), addr) == -1) {
547 				mdb_warn("couldn't read trap trace record "
548 				    "at %p", addr);
549 				return (DCMD_ERR);
550 			}
551 
552 			if (ttrace_walk(addr, &rec, &dcmd) == WALK_ERR)
553 				return (DCMD_ERR);
554 
555 			return (DCMD_OK);
556 		}
557 		dcmd.ttd_cpu = addr;
558 	}
559 
560 	if (mdb_readvar(&use_apix, "apix_enable") == -1) {
561 		mdb_warn("failed to read apix_enable");
562 		use_apix = 0;
563 	}
564 
565 	if (use_apix) {
566 		if (mdb_readvar(&d_apixs, "apixs") == -1) {
567 			mdb_warn("\nfailed to read apixs.");
568 			return (DCMD_ERR);
569 		}
570 		/* change to apix ttrace interrupt handler */
571 		ttrace_hdlr[4].t_hdlr = ttrace_apix_interrupt;
572 	}
573 
574 	if (mdb_walk("ttrace", (mdb_walk_cb_t)ttrace_walk, &dcmd) == -1) {
575 		mdb_warn("couldn't walk 'ttrace'");
576 		return (DCMD_ERR);
577 	}
578 
579 	return (DCMD_OK);
580 }
581 
582 /*ARGSUSED*/
583 int
584 mutex_owner_init(mdb_walk_state_t *wsp)
585 {
586 	return (WALK_NEXT);
587 }
588 
589 int
590 mutex_owner_step(mdb_walk_state_t *wsp)
591 {
592 	uintptr_t addr = wsp->walk_addr;
593 	mutex_impl_t mtx;
594 	uintptr_t owner;
595 	kthread_t thr;
596 
597 	if (mdb_vread(&mtx, sizeof (mtx), addr) == -1)
598 		return (WALK_ERR);
599 
600 	if (!MUTEX_TYPE_ADAPTIVE(&mtx))
601 		return (WALK_DONE);
602 
603 	if ((owner = (uintptr_t)MUTEX_OWNER(&mtx)) == NULL)
604 		return (WALK_DONE);
605 
606 	if (mdb_vread(&thr, sizeof (thr), owner) != -1)
607 		(void) wsp->walk_callback(owner, &thr, wsp->walk_cbdata);
608 
609 	return (WALK_DONE);
610 }
611 
612 static void
613 gate_desc_dump(gate_desc_t *gate, const char *label, int header)
614 {
615 	const char *lastnm;
616 	uint_t lastval;
617 	char type[4];
618 
619 	switch (gate->sgd_type) {
620 	case SDT_SYSIGT:
621 		strcpy(type, "int");
622 		break;
623 	case SDT_SYSTGT:
624 		strcpy(type, "trp");
625 		break;
626 	case SDT_SYSTASKGT:
627 		strcpy(type, "tsk");
628 		break;
629 	default:
630 		(void) mdb_snprintf(type, sizeof (type), "%3x", gate->sgd_type);
631 	}
632 
633 #if defined(__amd64)
634 	lastnm = "IST";
635 	lastval = gate->sgd_ist;
636 #else
637 	lastnm = "STK";
638 	lastval = gate->sgd_stkcpy;
639 #endif
640 
641 	if (header) {
642 		mdb_printf("%*s%<u>%-30s%</u> %<u>%-4s%</u> %<u>%3s%</u> "
643 		    "%<u>%1s%</u> %<u>%3s%</u> %<u>%3s%</u>\n", strlen(label),
644 		    "", "HANDLER", "SEL", "DPL", "P", "TYP", lastnm);
645 	}
646 
647 	mdb_printf("%s", label);
648 
649 	if (gate->sgd_type == SDT_SYSTASKGT)
650 		mdb_printf("%-30s ", "-");
651 	else
652 		mdb_printf("%-30a ", GATESEG_GETOFFSET(gate));
653 
654 	mdb_printf("%4x  %d  %c %3s %2x\n", gate->sgd_selector,
655 	    gate->sgd_dpl, (gate->sgd_p ? '+' : ' '), type, lastval);
656 }
657 
658 /*ARGSUSED*/
659 static int
660 gate_desc(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
661 {
662 	gate_desc_t gate;
663 
664 	if (argc != 0 || !(flags & DCMD_ADDRSPEC))
665 		return (DCMD_USAGE);
666 
667 	if (mdb_vread(&gate, sizeof (gate_desc_t), addr) !=
668 	    sizeof (gate_desc_t)) {
669 		mdb_warn("failed to read gate descriptor at %p\n", addr);
670 		return (DCMD_ERR);
671 	}
672 
673 	gate_desc_dump(&gate, "", DCMD_HDRSPEC(flags));
674 
675 	return (DCMD_OK);
676 }
677 
678 /*ARGSUSED*/
679 static int
680 idt(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
681 {
682 	int i;
683 
684 	if (!(flags & DCMD_ADDRSPEC)) {
685 		GElf_Sym idt0_va;
686 		gate_desc_t *idt0;
687 
688 		if (mdb_lookup_by_name("idt0", &idt0_va) < 0) {
689 			mdb_warn("failed to find VA of idt0");
690 			return (DCMD_ERR);
691 		}
692 
693 		addr = idt0_va.st_value;
694 		if (mdb_vread(&idt0, sizeof (idt0), addr) != sizeof (idt0)) {
695 			mdb_warn("failed to read idt0 at %p\n", addr);
696 			return (DCMD_ERR);
697 		}
698 
699 		addr = (uintptr_t)idt0;
700 	}
701 
702 	for (i = 0; i < NIDT; i++, addr += sizeof (gate_desc_t)) {
703 		gate_desc_t gate;
704 		char label[6];
705 
706 		if (mdb_vread(&gate, sizeof (gate_desc_t), addr) !=
707 		    sizeof (gate_desc_t)) {
708 			mdb_warn("failed to read gate descriptor at %p\n",
709 			    addr);
710 			return (DCMD_ERR);
711 		}
712 
713 		(void) mdb_snprintf(label, sizeof (label), "%3d: ", i);
714 		gate_desc_dump(&gate, label, i == 0);
715 	}
716 
717 	return (DCMD_OK);
718 }
719 
720 static void
721 htables_help(void)
722 {
723 	mdb_printf(
724 	    "Given a (hat_t *), generates the list of all (htable_t *)s\n"
725 	    "that correspond to that address space\n");
726 }
727 
728 static void
729 report_maps_help(void)
730 {
731 	mdb_printf(
732 	    "Given a PFN, report HAT structures that map the page, or use\n"
733 	    "the page as a pagetable.\n"
734 	    "\n"
735 	    "-m Interpret the PFN as an MFN (machine frame number)\n");
736 }
737 
738 static void
739 ptable_help(void)
740 {
741 	mdb_printf(
742 	    "Given a PFN holding a page table, print its contents, and\n"
743 	    "the address of the corresponding htable structure.\n"
744 	    "\n"
745 	    "-m Interpret the PFN as an MFN (machine frame number)\n");
746 }
747 
748 static const mdb_dcmd_t dcmds[] = {
749 	{ "gate_desc", ":", "dump a gate descriptor", gate_desc },
750 	{ "idt", ":[-v]", "dump an IDT", idt },
751 	{ "ttrace", "[-x]", "dump trap trace buffers", ttrace },
752 	{ "vatopfn", ":[-a as]", "translate address to physical page",
753 	    va2pfn_dcmd },
754 	{ "report_maps", ":[-m]",
755 	    "Given PFN, report mappings / page table usage",
756 	    report_maps_dcmd, report_maps_help },
757 	{ "htables", "", "Given hat_t *, lists all its htable_t * values",
758 	    htables_dcmd, htables_help },
759 	{ "ptable", ":[-m]", "Given PFN, dump contents of a page table",
760 	    ptable_dcmd, ptable_help },
761 	{ "pte", ":[-p XXXXX] [-l N]", "print human readable page table entry",
762 	    pte_dcmd },
763 	{ "pfntomfn", ":", "convert physical page to hypervisor machine page",
764 	    pfntomfn_dcmd },
765 	{ "mfntopfn", ":", "convert hypervisor machine page to physical page",
766 	    mfntopfn_dcmd },
767 	{ "memseg_list", ":", "show memseg list", memseg_list },
768 	{ NULL }
769 };
770 
771 static const mdb_walker_t walkers[] = {
772 	{ "ttrace", "walks trap trace buffers in reverse chronological order",
773 		ttrace_walk_init, ttrace_walk_step, ttrace_walk_fini },
774 	{ "mutex_owner", "walks the owner of a mutex",
775 		mutex_owner_init, mutex_owner_step },
776 	{ "memseg", "walk the memseg structures",
777 		memseg_walk_init, memseg_walk_step, memseg_walk_fini },
778 	{ NULL }
779 };
780 
781 static const mdb_modinfo_t modinfo = { MDB_API_VERSION, dcmds, walkers };
782 
783 const mdb_modinfo_t *
784 _mdb_init(void)
785 {
786 	return (&modinfo);
787 }
788 
789 void
790 _mdb_fini(void)
791 {
792 	free_mmu();
793 }
794