xref: /illumos-gate/usr/src/cmd/mdb/intel/kmdb/kvm_isadep.c (revision 438b5f69eb4f998015cc0835f19f2f80663f2f53)
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 2007 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 #pragma ident	"%Z%%M%	%I%	%E% SMI"
27 
28 /*
29  * isa-dependent portions of the kmdb target
30  */
31 
32 #include <kmdb/kvm.h>
33 #include <kmdb/kvm_cpu.h>
34 #include <kmdb/kmdb_kdi.h>
35 #include <kmdb/kmdb_asmutil.h>
36 #include <mdb/mdb_debug.h>
37 #include <mdb/mdb_err.h>
38 #include <mdb/mdb_list.h>
39 #include <mdb/mdb_target_impl.h>
40 #include <mdb/mdb_isautil.h>
41 #include <mdb/mdb_kreg_impl.h>
42 #include <mdb/mdb.h>
43 
44 #include <sys/types.h>
45 #include <sys/frame.h>
46 #include <sys/trap.h>
47 #include <sys/bitmap.h>
48 #include <sys/pci_impl.h>
49 
50 /* Higher than the highest trap number for which we have a defined specifier */
51 #define	KMT_MAXTRAPNO	0x20
52 
53 #define	IOPORTLIMIT	0xffff	/* XXX find a new home for this */
54 
55 const char *
56 kmt_def_dismode(void)
57 {
58 #ifdef	__amd64
59 	return ("amd64");
60 #else
61 	return ("ia32");
62 #endif
63 }
64 
65 int
66 kmt_step_out_validate(mdb_tgt_t *t, uintptr_t pc)
67 {
68 	kmt_data_t *kmt = t->t_data;
69 	int i;
70 
71 	for (i = 0; i < sizeof (kmt->kmt_intrsyms) / sizeof (GElf_Sym); i++) {
72 		GElf_Sym *sym = (GElf_Sym *)&kmt->kmt_intrsyms + i;
73 
74 		if (pc >= sym->st_value && pc < sym->st_value + sym->st_size)
75 			return (0);
76 	}
77 
78 	return (1);
79 }
80 
81 /*
82  * Determine the return address for the current frame.
83  */
84 int
85 kmt_step_out(mdb_tgt_t *t, uintptr_t *p)
86 {
87 	mdb_instr_t instr;
88 	kreg_t pc, sp, fp;
89 
90 	(void) kmdb_dpi_get_register("pc", &pc);
91 	(void) kmdb_dpi_get_register("sp", &sp);
92 	(void) kmdb_dpi_get_register("fp", &fp);
93 
94 	if (mdb_tgt_vread(t, &instr, sizeof (mdb_instr_t), pc) !=
95 	    sizeof (mdb_instr_t))
96 		return (-1); /* errno is set for us */
97 
98 	if (!kmt_step_out_validate(t, pc))
99 		return (set_errno(EMDB_TGTNOTSUP));
100 
101 	return (mdb_isa_step_out(t, p, pc, fp, sp, instr));
102 }
103 
104 int
105 kmt_step_branch(mdb_tgt_t *t)
106 {
107 	kmt_data_t *kmt = t->t_data;
108 
109 	return (kmt_cpu_step_branch(t, kmt->kmt_cpu));
110 }
111 
112 /*
113  * Return the address of the next instruction following a call, or return -1
114  * and set errno to EAGAIN if the target should just single-step.
115  */
116 int
117 kmt_next(mdb_tgt_t *t, uintptr_t *p)
118 {
119 	kreg_t pc;
120 	mdb_instr_t instr;
121 
122 	(void) kmdb_dpi_get_register("pc", &pc);
123 
124 	if (mdb_tgt_vread(t, &instr, sizeof (mdb_instr_t), pc) !=
125 	    sizeof (mdb_instr_t))
126 		return (-1); /* errno is set for us */
127 
128 	return (mdb_isa_next(t, p, pc, instr));
129 }
130 
131 /*ARGSUSED*/
132 static int
133 kmt_stack_common(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv,
134     int cpuid, mdb_tgt_stack_f *func)
135 {
136 	const mdb_tgt_gregset_t *grp = NULL;
137 	mdb_tgt_gregset_t gregs;
138 	void *arg = (void *)(uintptr_t)mdb.m_nargs;
139 
140 	if (flags & DCMD_ADDRSPEC) {
141 		bzero(&gregs, sizeof (gregs));
142 		gregs.kregs[KREG_FP] = addr;
143 		grp = &gregs;
144 	} else
145 		grp = kmdb_dpi_get_gregs(cpuid);
146 
147 	if (grp == NULL) {
148 		warn("failed to retrieve registers for cpu %d", cpuid);
149 		return (DCMD_ERR);
150 	}
151 
152 	if (argc != 0) {
153 		if (argv->a_type == MDB_TYPE_CHAR || argc > 1)
154 			return (DCMD_USAGE);
155 
156 		if (argv->a_type == MDB_TYPE_STRING)
157 			arg = (void *)(uintptr_t)mdb_strtoull(argv->a_un.a_str);
158 		else
159 			arg = (void *)(uintptr_t)argv->a_un.a_val;
160 	}
161 
162 	(void) mdb_isa_kvm_stack_iter(mdb.m_target, grp, func, arg);
163 
164 	return (DCMD_OK);
165 }
166 
167 int
168 kmt_cpustack(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv,
169     int cpuid, int verbose)
170 {
171 	return (kmt_stack_common(addr, flags, argc, argv, cpuid,
172 	    (verbose ? mdb_isa_kvm_framev : mdb_isa_kvm_frame)));
173 }
174 
175 int
176 kmt_stack(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
177 {
178 	return (kmt_stack_common(addr, flags, argc, argv, DPI_MASTER_CPUID,
179 	    mdb_isa_kvm_frame));
180 }
181 
182 int
183 kmt_stackv(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
184 {
185 	return (kmt_stack_common(addr, flags, argc, argv, DPI_MASTER_CPUID,
186 	    mdb_isa_kvm_framev));
187 }
188 
189 int
190 kmt_stackr(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
191 {
192 	return (kmt_stack_common(addr, flags, argc, argv, DPI_MASTER_CPUID,
193 	    mdb_isa_kvm_framev));
194 }
195 
196 /*ARGSUSED*/
197 void
198 kmt_printregs(const mdb_tgt_gregset_t *gregs)
199 {
200 	mdb_isa_printregs(gregs);
201 }
202 
203 #define	IOCHECK_NOWARN	0
204 #define	IOCHECK_WARN	1
205 
206 static int
207 kmt_io_check(uint64_t nbytes, uintptr_t addr, int dowarn)
208 {
209 	if (addr > IOPORTLIMIT) {
210 		if (dowarn)
211 			warn("port address must be 0-%#x\n", IOPORTLIMIT);
212 		return (set_errno(EINVAL));
213 	}
214 
215 	if (nbytes != 1 && nbytes != 2 && nbytes != 4) {
216 		if (dowarn)
217 			warn("port access must be 1, 2, or 4 bytes\n");
218 		return (set_errno(EINVAL));
219 	}
220 
221 	if ((addr & (nbytes - 1)) != 0) {
222 		if (dowarn) {
223 			warn("address for %llu-byte access must be %llu-byte "
224 			    "aligned\n", (u_longlong_t)nbytes,
225 			    (u_longlong_t)nbytes);
226 		}
227 		return (set_errno(EINVAL));
228 	}
229 
230 	return (0);
231 }
232 
233 /*ARGSUSED1*/
234 int
235 kmt_in_dcmd(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
236 {
237 	uint64_t len = 0;
238 	uint32_t buf;
239 
240 	if (mdb_getopts(argc, argv,
241 	    'L', MDB_OPT_UINT64, &len,
242 	    NULL) != argc)
243 		return (DCMD_USAGE);
244 
245 	if (len == 0)
246 		len = mdb.m_dcount;
247 
248 	if (kmt_io_check(len, addr, IOCHECK_WARN) < 0)
249 		return (DCMD_ERR);
250 
251 	if (mdb_tgt_ioread(mdb.m_target, &buf, len, addr) < 0) {
252 		warn("failed to read from port 0x%llx", (u_longlong_t)addr);
253 		return (DCMD_ERR);
254 	}
255 
256 	mdb_printf("%x\n", buf);
257 
258 	return (DCMD_OK);
259 }
260 
261 static uint64_t
262 kmt_numarg(const mdb_arg_t *arg)
263 {
264 	if (arg->a_type == MDB_TYPE_STRING)
265 		return (mdb_strtoull(arg->a_un.a_str));
266 	else
267 		return (arg->a_un.a_val);
268 }
269 
270 /*ARGSUSED1*/
271 int
272 kmt_out_dcmd(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
273 {
274 	uint64_t len = 0;
275 	uint64_t val;
276 
277 	if (mdb_getopts(argc, argv,
278 	    'L', MDB_OPT_UINT64, &len,
279 	    NULL) != argc - 1)
280 		return (DCMD_USAGE);
281 
282 	if (len == 0)
283 		len = mdb.m_dcount;
284 
285 	argv += argc - 1;
286 	val = kmt_numarg(argv);
287 
288 	if (kmt_io_check(len, addr, IOCHECK_WARN) < 0)
289 		return (DCMD_ERR);
290 
291 	if (val > (1ULL << (len * NBBY)) - 1) {
292 		warn("value is out of range for port size\n");
293 		return (DCMD_ERR);
294 	}
295 
296 	if (mdb_tgt_iowrite(mdb.m_target, &val, len, addr) < 0) {
297 		warn("failed to write to port %llx", (u_longlong_t)addr);
298 		return (DCMD_ERR);
299 	}
300 
301 	return (DCMD_OK);
302 }
303 
304 static int
305 kmt_rwmsr(uint32_t addr, uint64_t *valp, void (*rw)(uint32_t, uint64_t *))
306 {
307 	jmp_buf pcb, *oldpcb = NULL;
308 
309 	if (setjmp(pcb) != 0) {
310 		kmdb_dpi_restore_fault_hdlr(oldpcb);
311 		return (-1); /* errno is set for us */
312 	}
313 
314 	oldpcb = kmdb_dpi_set_fault_hdlr(&pcb);
315 	rw(addr, valp);
316 	kmdb_dpi_restore_fault_hdlr(oldpcb);
317 
318 	return (0);
319 }
320 
321 /*ARGSUSED*/
322 int
323 kmt_rdmsr(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
324 {
325 	uint64_t val;
326 
327 	if (!(flags & DCMD_ADDRSPEC))
328 		return (DCMD_USAGE);
329 
330 	if (kmt_rwmsr(addr, &val, rdmsr) < 0) {
331 		warn("rdmsr failed");
332 		return (DCMD_ERR);
333 	}
334 
335 	mdb_printf("%llx\n", (u_longlong_t)val);
336 
337 	return (DCMD_OK);
338 }
339 
340 /*ARGSUSED*/
341 int
342 kmt_wrmsr(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
343 {
344 	uint64_t val;
345 
346 	if (!(flags & DCMD_ADDRSPEC) || argc != 1)
347 		return (DCMD_USAGE);
348 
349 	val = kmt_numarg(argv);
350 
351 	if (kmt_rwmsr(addr, &val, wrmsr)) {
352 		warn("wrmsr failed");
353 		return (DCMD_ERR);
354 	}
355 
356 	return (DCMD_OK);
357 }
358 
359 int
360 kmt_msr_validate(const kdi_msr_t *msr)
361 {
362 	uint64_t val;
363 
364 	for (/* */; msr->msr_num != 0; msr++) {
365 		if (kmt_rwmsr(msr->msr_num, &val, rdmsr) < 0)
366 			return (0);
367 	}
368 
369 	return (1);
370 }
371 
372 /*ARGSUSED*/
373 ssize_t
374 kmt_write(mdb_tgt_t *t, const void *buf, size_t nbytes, uintptr_t addr)
375 {
376 	if (!(t->t_flags & MDB_TGT_F_ALLOWIO) &&
377 	    (nbytes = kmdb_kdi_range_is_nontoxic(addr, nbytes, 1)) == 0)
378 		return (set_errno(EMDB_NOMAP));
379 
380 	/*
381 	 * No writes to user space are allowed.  If we were to allow it, we'd
382 	 * be in the unfortunate situation where kmdb could place a breakpoint
383 	 * on a userspace executable page; this dirty page would end up being
384 	 * flushed back to disk, incurring sadness when it's next executed.
385 	 * Besides, we can't allow trapping in from userspace anyway.
386 	 */
387 	if (addr < kmdb_kdi_get_userlimit())
388 		return (set_errno(EMDB_TGTNOTSUP));
389 
390 	return (kmt_rw(t, (void *)buf, nbytes, addr, kmt_writer));
391 }
392 
393 /*ARGSUSED*/
394 static ssize_t
395 kmt_iorw(mdb_tgt_t *t, void *buf, size_t nbytes, uint64_t addr,
396     void (*iorw)(void *, size_t, uintptr_t))
397 {
398 	jmp_buf pcb, *oldpcb = NULL;
399 
400 	if (kmt_io_check(nbytes, addr, IOCHECK_NOWARN) < 0)
401 		return (-1); /* errno is set for us */
402 
403 	if (setjmp(pcb) != 0) {
404 		kmdb_dpi_restore_fault_hdlr(oldpcb);
405 		return (-1); /* errno is set for us */
406 	}
407 
408 	oldpcb = kmdb_dpi_set_fault_hdlr(&pcb);
409 	iorw(buf, nbytes, addr);
410 	kmdb_dpi_restore_fault_hdlr(oldpcb);
411 
412 	return (nbytes);
413 }
414 
415 /*ARGSUSED*/
416 ssize_t
417 kmt_ioread(mdb_tgt_t *t, void *buf, size_t nbytes, uintptr_t addr)
418 {
419 	return (kmt_iorw(t, buf, nbytes, addr, kmt_in));
420 }
421 
422 /*ARGSUSED*/
423 ssize_t
424 kmt_iowrite(mdb_tgt_t *t, const void *buf, size_t nbytes, uintptr_t addr)
425 {
426 	return (kmt_iorw(t, (void *)buf, nbytes, addr, kmt_out));
427 }
428 
429 static int
430 kmt_pcicfg_common(uintptr_t off, uint32_t *valp, const mdb_arg_t *argv,
431     void (*rw)(void *, size_t, uintptr_t))
432 {
433 	uint32_t bus, dev, func;
434 	uint32_t addr;
435 
436 	bus = kmt_numarg(&argv[0]);
437 	dev = kmt_numarg(&argv[1]);
438 	func = kmt_numarg(&argv[2]);
439 
440 	if ((bus & 0xffff) != bus) {
441 		warn("invalid bus number (must be 0-0xffff)\n");
442 		return (DCMD_ERR);
443 	}
444 
445 	if ((dev & 0x1f) != dev) {
446 		warn("invalid device number (must be 0-0x1f)\n");
447 		return (DCMD_ERR);
448 	}
449 
450 	if ((func & 0x7) != func) {
451 		warn("invalid function number (must be 0-7)\n");
452 		return (DCMD_ERR);
453 	}
454 
455 	if ((off & 0xfc) != off) {
456 		warn("invalid register number (must be 0-0xff, and 4-byte "
457 		    "aligned\n");
458 		return (DCMD_ERR);
459 	}
460 
461 	addr = PCI_CADDR1(bus, dev, func, off);
462 
463 	if (kmt_iowrite(mdb.m_target, &addr, sizeof (addr), PCI_CONFADD) !=
464 	    sizeof (addr)) {
465 		warn("write of PCI_CONFADD failed");
466 		return (DCMD_ERR);
467 	}
468 
469 	if (kmt_iorw(mdb.m_target, valp, sizeof (*valp), PCI_CONFDATA, rw) !=
470 	    sizeof (*valp)) {
471 		warn("access to PCI_CONFDATA failed");
472 		return (DCMD_ERR);
473 	}
474 
475 	return (DCMD_OK);
476 }
477 
478 /*ARGSUSED*/
479 int
480 kmt_rdpcicfg(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
481 {
482 	uint32_t val;
483 
484 	if (argc != 3 || !(flags & DCMD_ADDRSPEC))
485 		return (DCMD_USAGE);
486 
487 	if (kmt_pcicfg_common(addr, &val, argv, kmt_in) != DCMD_OK)
488 		return (DCMD_ERR);
489 
490 	mdb_printf("%llx\n", (u_longlong_t)val);
491 
492 	return (DCMD_OK);
493 }
494 
495 /*ARGSUSED*/
496 int
497 kmt_wrpcicfg(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
498 {
499 	uint32_t val;
500 
501 	if (argc != 4 || !(flags & DCMD_ADDRSPEC))
502 		return (DCMD_USAGE);
503 
504 	val = (uint32_t)kmt_numarg(&argv[3]);
505 
506 	if (kmt_pcicfg_common(addr, &val, argv, kmt_out) != DCMD_OK)
507 		return (DCMD_ERR);
508 
509 	return (DCMD_OK);
510 }
511 
512 const char *
513 kmt_trapname(int trapnum)
514 {
515 	static char trapname[11];
516 
517 	switch (trapnum) {
518 	case T_ZERODIV:
519 		return ("division by zero (#de) trap");
520 	case T_SGLSTP:
521 		return ("single-step (#db) trap");
522 	case T_NMIFLT:
523 		return ("NMI");
524 	case T_BPTFLT:
525 		return ("breakpoint (#bp) trap");
526 	case T_ILLINST:
527 		return ("illegal instruction (#ud) trap");
528 	case T_SEGFLT:
529 		return ("segment not present (#np) trap");
530 	case T_STKFLT:
531 		return ("stack (#ss) trap");
532 	case T_GPFLT:
533 		return ("general protection (#gp) trap");
534 	case T_PGFLT:
535 		return ("page fault (#pf) trap");
536 	case T_ALIGNMENT:
537 		return ("alignment check (#ac) trap");
538 	case T_MCE:
539 		return ("machine check (#mc) trap");
540 	case T_SIMDFPE:
541 		return ("SSE/SSE2 (#xm) trap");
542 	case T_DBGENTR:
543 		return ("debugger entry trap");
544 	default:
545 		(void) mdb_snprintf(trapname, sizeof (trapname), "trap %#x",
546 		    trapnum);
547 		return (trapname);
548 	}
549 }
550 
551 void
552 kmt_init_isadep(mdb_tgt_t *t)
553 {
554 	kmt_data_t *kmt = t->t_data;
555 
556 	kmt->kmt_rds = mdb_isa_kregs;
557 
558 	kmt->kmt_trapmax = KMT_MAXTRAPNO;
559 	kmt->kmt_trapmap = mdb_zalloc(BT_SIZEOFMAP(kmt->kmt_trapmax), UM_SLEEP);
560 
561 	/* Traps for which we want to provide an explicit message */
562 	(void) mdb_tgt_add_fault(t, T_ZERODIV, MDB_TGT_SPEC_INTERNAL,
563 	    no_se_f, NULL);
564 	(void) mdb_tgt_add_fault(t, T_ILLINST, MDB_TGT_SPEC_INTERNAL,
565 	    no_se_f, NULL);
566 	(void) mdb_tgt_add_fault(t, T_SEGFLT, MDB_TGT_SPEC_INTERNAL,
567 	    no_se_f, NULL);
568 	(void) mdb_tgt_add_fault(t, T_STKFLT, MDB_TGT_SPEC_INTERNAL,
569 	    no_se_f, NULL);
570 	(void) mdb_tgt_add_fault(t, T_GPFLT, MDB_TGT_SPEC_INTERNAL,
571 	    no_se_f, NULL);
572 	(void) mdb_tgt_add_fault(t, T_PGFLT, MDB_TGT_SPEC_INTERNAL,
573 	    no_se_f, NULL);
574 	(void) mdb_tgt_add_fault(t, T_ALIGNMENT, MDB_TGT_SPEC_INTERNAL,
575 	    no_se_f, NULL);
576 	(void) mdb_tgt_add_fault(t, T_MCE, MDB_TGT_SPEC_INTERNAL,
577 	    no_se_f, NULL);
578 	(void) mdb_tgt_add_fault(t, T_SIMDFPE, MDB_TGT_SPEC_INTERNAL,
579 	    no_se_f, NULL);
580 
581 	/*
582 	 * Traps which will be handled elsewhere, and which therefore don't
583 	 * need the trap-based message.
584 	 */
585 	BT_SET(kmt->kmt_trapmap, T_SGLSTP);
586 	BT_SET(kmt->kmt_trapmap, T_BPTFLT);
587 	BT_SET(kmt->kmt_trapmap, T_DBGENTR);
588 
589 	/* Catch-all for traps not explicitly listed here */
590 	(void) mdb_tgt_add_fault(t, KMT_TRAP_NOTENUM, MDB_TGT_SPEC_INTERNAL,
591 	    no_se_f, NULL);
592 }
593 
594 void
595 kmt_startup_isadep(mdb_tgt_t *t)
596 {
597 	kmt_data_t *kmt = t->t_data;
598 
599 	/*
600 	 * The stack trace and ::step out code need to detect "interrupt"
601 	 * frames.  The heuristic they use to detect said frames requires the
602 	 * addresses of routines that can generate them.
603 	 */
604 	(void) mdb_tgt_lookup_by_name(t, MDB_TGT_OBJ_EXEC,
605 	    "cmnint", &kmt->kmt_intrsyms._kmt_cmnint, NULL);
606 	(void) mdb_tgt_lookup_by_name(t, MDB_TGT_OBJ_EXEC,
607 	    "cmntrap", &kmt->kmt_intrsyms._kmt_cmntrap, NULL);
608 	(void) mdb_tgt_lookup_by_name(t, MDB_TGT_OBJ_EXEC,
609 	    "sys_sysenter", &kmt->kmt_intrsyms._kmt_sysenter, NULL);
610 	(void) mdb_tgt_lookup_by_name(t, MDB_TGT_OBJ_EXEC,
611 	    "brand_sys_sysenter", &kmt->kmt_intrsyms._kmt_brand_sysenter, NULL);
612 #if defined(__amd64)
613 	(void) mdb_tgt_lookup_by_name(t, MDB_TGT_OBJ_EXEC,
614 	    "sys_syscall", &kmt->kmt_intrsyms._kmt_syscall, NULL);
615 	(void) mdb_tgt_lookup_by_name(t, MDB_TGT_OBJ_EXEC,
616 	    "brand_sys_syscall", &kmt->kmt_intrsyms._kmt_brand_syscall, NULL);
617 #endif
618 }
619