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 */
27
28 /*
29 * Libkvm Kernel Target SPARC v7 component
30 *
31 * This file provides the ISA-dependent portion of the libkvm kernel target.
32 * For more details on the implementation refer to mdb_kvm.c.
33 */
34
35 #include <sys/types.h>
36 #include <sys/machtypes.h>
37 #include <sys/regset.h>
38 #include <sys/frame.h>
39 #include <sys/stack.h>
40 #include <sys/sysmacros.h>
41 #include <sys/panic.h>
42 #include <strings.h>
43
44 #include <mdb/mdb_target_impl.h>
45 #include <mdb/mdb_disasm.h>
46 #include <mdb/mdb_modapi.h>
47 #include <mdb/mdb_conf.h>
48 #include <mdb/mdb_kreg.h>
49 #include <mdb/mdb_kvm.h>
50 #include <mdb/mdb_err.h>
51 #include <mdb/mdb_debug.h>
52 #include <mdb/mdb.h>
53
54 /*
55 * The mdb_tgt_gregset type is opaque to callers of the target interface
56 * and to our own target common code. We now can define it explicitly.
57 */
58 struct mdb_tgt_gregset {
59 kreg_t kregs[KREG_NGREG];
60 };
61
62 /*
63 * We also define an array of register names and their corresponding
64 * array indices. This is used by the getareg and putareg entry points,
65 * and also by our register variable discipline.
66 */
67 static const mdb_tgt_regdesc_t kt_sparcv7_regs[] = {
68 { "g0", KREG_G0, MDB_TGT_R_EXPORT },
69 { "g1", KREG_G1, MDB_TGT_R_EXPORT },
70 { "g2", KREG_G2, MDB_TGT_R_EXPORT },
71 { "g3", KREG_G3, MDB_TGT_R_EXPORT },
72 { "g4", KREG_G4, MDB_TGT_R_EXPORT },
73 { "g5", KREG_G5, MDB_TGT_R_EXPORT },
74 { "g6", KREG_G6, MDB_TGT_R_EXPORT },
75 { "g7", KREG_G7, MDB_TGT_R_EXPORT },
76 { "o0", KREG_O0, MDB_TGT_R_EXPORT },
77 { "o1", KREG_O1, MDB_TGT_R_EXPORT },
78 { "o2", KREG_O2, MDB_TGT_R_EXPORT },
79 { "o3", KREG_O3, MDB_TGT_R_EXPORT },
80 { "o4", KREG_O4, MDB_TGT_R_EXPORT },
81 { "o5", KREG_O5, MDB_TGT_R_EXPORT },
82 { "o6", KREG_O6, MDB_TGT_R_EXPORT },
83 { "o7", KREG_O7, MDB_TGT_R_EXPORT },
84 { "l0", KREG_L0, MDB_TGT_R_EXPORT },
85 { "l1", KREG_L1, MDB_TGT_R_EXPORT },
86 { "l2", KREG_L2, MDB_TGT_R_EXPORT },
87 { "l3", KREG_L3, MDB_TGT_R_EXPORT },
88 { "l4", KREG_L4, MDB_TGT_R_EXPORT },
89 { "l5", KREG_L5, MDB_TGT_R_EXPORT },
90 { "l6", KREG_L6, MDB_TGT_R_EXPORT },
91 { "l7", KREG_L7, MDB_TGT_R_EXPORT },
92 { "i0", KREG_I0, MDB_TGT_R_EXPORT },
93 { "i1", KREG_I1, MDB_TGT_R_EXPORT },
94 { "i2", KREG_I2, MDB_TGT_R_EXPORT },
95 { "i3", KREG_I3, MDB_TGT_R_EXPORT },
96 { "i4", KREG_I4, MDB_TGT_R_EXPORT },
97 { "i5", KREG_I5, MDB_TGT_R_EXPORT },
98 { "i6", KREG_I6, MDB_TGT_R_EXPORT },
99 { "i7", KREG_I7, MDB_TGT_R_EXPORT },
100 { "psr", KREG_PSR, MDB_TGT_R_EXPORT },
101 { "pc", KREG_PC, MDB_TGT_R_EXPORT },
102 { "npc", KREG_NPC, MDB_TGT_R_EXPORT },
103 { "y", KREG_Y, 0 },
104 { "wim", KREG_WIM, MDB_TGT_R_EXPORT | MDB_TGT_R_PRIV },
105 { "tbr", KREG_TBR, MDB_TGT_R_EXPORT | MDB_TGT_R_PRIV },
106 { "sp", KREG_SP, MDB_TGT_R_EXPORT | MDB_TGT_R_ALIAS },
107 { "fp", KREG_FP, MDB_TGT_R_EXPORT | MDB_TGT_R_ALIAS },
108 { NULL, 0, 0 }
109 };
110
111 static int
112 kt_getareg(mdb_tgt_t *t, mdb_tgt_tid_t tid,
113 const char *rname, mdb_tgt_reg_t *rp)
114 {
115 const mdb_tgt_regdesc_t *rdp;
116 kt_data_t *kt = t->t_data;
117
118 if (tid != kt->k_tid)
119 return (set_errno(EMDB_NOREGS));
120
121 for (rdp = kt->k_rds; rdp->rd_name != NULL; rdp++) {
122 if (strcmp(rname, rdp->rd_name) == 0) {
123 *rp = kt->k_regs->kregs[rdp->rd_num];
124 return (0);
125 }
126 }
127
128 return (set_errno(EMDB_BADREG));
129 }
130
131 static int
132 kt_putareg(mdb_tgt_t *t, mdb_tgt_tid_t tid, const char *rname, mdb_tgt_reg_t r)
133 {
134 const mdb_tgt_regdesc_t *rdp;
135 kt_data_t *kt = t->t_data;
136
137 if (tid != kt->k_tid)
138 return (set_errno(EMDB_NOREGS));
139
140 for (rdp = kt->k_rds; rdp->rd_name != NULL; rdp++) {
141 if (strcmp(rname, rdp->rd_name) == 0) {
142 kt->k_regs->kregs[rdp->rd_num] = r;
143 return (0);
144 }
145 }
146
147 return (set_errno(EMDB_BADREG));
148 }
149
150 static int
151 kt_stack_iter(mdb_tgt_t *t, const mdb_tgt_gregset_t *gsp,
152 mdb_tgt_stack_f *func, void *arg)
153 {
154 mdb_tgt_gregset_t gregs;
155 kreg_t *kregs = &gregs.kregs[0];
156 int got_pc = (gsp->kregs[KREG_PC] != 0);
157
158 struct rwindow rwin;
159 uintptr_t sp;
160 long argv[6];
161 int i;
162
163 bcopy(gsp, &gregs, sizeof (gregs));
164
165 for (;;) {
166 for (i = 0; i < 6; i++)
167 argv[i] = kregs[KREG_I0 + i];
168
169 if (got_pc && func(arg, kregs[KREG_PC], 6, argv, &gregs) != 0)
170 break;
171
172 kregs[KREG_PC] = kregs[KREG_I7];
173 kregs[KREG_NPC] = kregs[KREG_PC] + 4;
174
175 bcopy(&kregs[KREG_I0], &kregs[KREG_O0], 8 * sizeof (kreg_t));
176 got_pc |= (kregs[KREG_PC] != 0);
177
178 if ((sp = kregs[KREG_FP]) == 0)
179 break; /* Stop if we're at the end of the stack */
180
181 if (sp & (STACK_ALIGN - 1))
182 return (set_errno(EMDB_STKALIGN));
183
184 if (mdb_tgt_vread(t, &rwin, sizeof (rwin), sp) != sizeof (rwin))
185 return (-1); /* Failed to read frame */
186
187 for (i = 0; i < 8; i++)
188 kregs[KREG_L0 + i] = (uintptr_t)rwin.rw_local[i];
189 for (i = 0; i < 8; i++)
190 kregs[KREG_I0 + i] = (uintptr_t)rwin.rw_in[i];
191 }
192
193 return (0);
194 }
195
196 /*ARGSUSED*/
197 static int
198 kt_regs(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
199 {
200 mdb_tgt_gregset_t *k_regs = (mdb_tgt_gregset_t *)addr;
201 const kreg_t *kregs = &k_regs->kregs[0];
202
203 if (argc != 0 || (flags & DCMD_ADDRSPEC))
204 return (DCMD_USAGE);
205
206 #define GETREG2(x) ((uintptr_t)kregs[(x)]), ((uintptr_t)kregs[(x)])
207
208 mdb_printf("%%g0 = 0x%0?p %15A %%l0 = 0x%0?p %A\n",
209 GETREG2(KREG_G0), GETREG2(KREG_L0));
210
211 mdb_printf("%%g1 = 0x%0?p %15A %%l1 = 0x%0?p %A\n",
212 GETREG2(KREG_G1), GETREG2(KREG_L1));
213
214 mdb_printf("%%g2 = 0x%0?p %15A %%l2 = 0x%0?p %A\n",
215 GETREG2(KREG_G2), GETREG2(KREG_L2));
216
217 mdb_printf("%%g3 = 0x%0?p %15A %%l3 = 0x%0?p %A\n",
218 GETREG2(KREG_G3), GETREG2(KREG_L3));
219
220 mdb_printf("%%g4 = 0x%0?p %15A %%l4 = 0x%0?p %A\n",
221 GETREG2(KREG_G4), GETREG2(KREG_L4));
222
223 mdb_printf("%%g5 = 0x%0?p %15A %%l5 = 0x%0?p %A\n",
224 GETREG2(KREG_G5), GETREG2(KREG_L5));
225
226 mdb_printf("%%g6 = 0x%0?p %15A %%l6 = 0x%0?p %A\n",
227 GETREG2(KREG_G6), GETREG2(KREG_L6));
228
229 mdb_printf("%%g7 = 0x%0?p %15A %%l7 = 0x%0?p %A\n\n",
230 GETREG2(KREG_G7), GETREG2(KREG_L7));
231
232 mdb_printf("%%o0 = 0x%0?p %15A %%i0 = 0x%0?p %A\n",
233 GETREG2(KREG_O0), GETREG2(KREG_I0));
234
235 mdb_printf("%%o1 = 0x%0?p %15A %%i1 = 0x%0?p %A\n",
236 GETREG2(KREG_O1), GETREG2(KREG_I1));
237
238 mdb_printf("%%o2 = 0x%0?p %15A %%i2 = 0x%0?p %A\n",
239 GETREG2(KREG_O2), GETREG2(KREG_I2));
240
241 mdb_printf("%%o3 = 0x%0?p %15A %%i3 = 0x%0?p %A\n",
242 GETREG2(KREG_O3), GETREG2(KREG_I3));
243
244 mdb_printf("%%o4 = 0x%0?p %15A %%i4 = 0x%0?p %A\n",
245 GETREG2(KREG_O4), GETREG2(KREG_I4));
246
247 mdb_printf("%%o5 = 0x%0?p %15A %%i5 = 0x%0?p %A\n",
248 GETREG2(KREG_O5), GETREG2(KREG_I5));
249
250 mdb_printf("%%o6 = 0x%0?p %15A %%i6 = 0x%0?p %A\n",
251 GETREG2(KREG_O6), GETREG2(KREG_I6));
252
253 mdb_printf("%%o7 = 0x%0?p %15A %%i7 = 0x%0?p %A\n\n",
254 GETREG2(KREG_O7), GETREG2(KREG_I7));
255
256 mdb_printf(" %%psr = 0x%08x impl=0x%x ver=0x%x icc=%c%c%c%c\n"
257 " ec=%u ef=%u pil=%u s=%u ps=%u et=%u cwp=0x%x\n",
258 kregs[KREG_PSR],
259 (kregs[KREG_PSR] & KREG_PSR_IMPL_MASK) >> KREG_PSR_IMPL_SHIFT,
260 (kregs[KREG_PSR] & KREG_PSR_VER_MASK) >> KREG_PSR_VER_SHIFT,
261 (kregs[KREG_PSR] & KREG_PSR_ICC_N_MASK) ? 'N' : 'n',
262 (kregs[KREG_PSR] & KREG_PSR_ICC_Z_MASK) ? 'Z' : 'z',
263 (kregs[KREG_PSR] & KREG_PSR_ICC_V_MASK) ? 'V' : 'v',
264 (kregs[KREG_PSR] & KREG_PSR_ICC_C_MASK) ? 'C' : 'c',
265 kregs[KREG_PSR] & KREG_PSR_EC_MASK,
266 kregs[KREG_PSR] & KREG_PSR_EF_MASK,
267 (kregs[KREG_PSR] & KREG_PSR_PIL_MASK) >> KREG_PSR_PIL_SHIFT,
268 kregs[KREG_PSR] & KREG_PSR_S_MASK,
269 kregs[KREG_PSR] & KREG_PSR_PS_MASK,
270 kregs[KREG_PSR] & KREG_PSR_ET_MASK,
271 (kregs[KREG_PSR] & KREG_PSR_CWP_MASK) >> KREG_PSR_CWP_SHIFT);
272
273 mdb_printf(" %%y = 0x%0?p\n", kregs[KREG_Y]);
274
275 mdb_printf(" %%pc = 0x%0?p %A\n", GETREG2(KREG_PC));
276 mdb_printf(" %%npc = 0x%0?p %A\n", GETREG2(KREG_NPC));
277
278 mdb_printf(" %%sp = 0x%0?p\n", kregs[KREG_SP]);
279 mdb_printf(" %%fp = 0x%0?p\n\n", kregs[KREG_FP]);
280
281 mdb_printf(" %%wim = 0x%08lx\n", kregs[KREG_WIM]);
282 mdb_printf(" %%tbr = 0x%08lx\n", kregs[KREG_TBR]);
283
284 return (DCMD_OK);
285 }
286
287 /*ARGSUSED*/
288 static int
289 kt_frame(void *arglim, uintptr_t pc, uint_t argc, const long *argv,
290 const mdb_tgt_gregset_t *gregs)
291 {
292 argc = MIN(argc, (uint_t)arglim);
293 mdb_printf("%a(", pc);
294
295 if (argc != 0) {
296 mdb_printf("%lr", *argv++);
297 for (argc--; argc != 0; argc--)
298 mdb_printf(", %lr", *argv++);
299 }
300
301 mdb_printf(")\n");
302 return (0);
303 }
304
305 static int
306 kt_framev(void *arglim, uintptr_t pc, uint_t argc, const long *argv,
307 const mdb_tgt_gregset_t *gregs)
308 {
309 argc = MIN(argc, (uint_t)arglim);
310 mdb_printf("%0?lr %a(", gregs->kregs[KREG_SP], pc);
311
312 if (argc != 0) {
313 mdb_printf("%lr", *argv++);
314 for (argc--; argc != 0; argc--)
315 mdb_printf(", %lr", *argv++);
316 }
317
318 mdb_printf(")\n");
319 return (0);
320 }
321
322 static int
323 kt_stack_common(uintptr_t addr, uint_t flags, int argc,
324 const mdb_arg_t *argv, mdb_tgt_stack_f *func)
325 {
326 kt_data_t *kt = mdb.m_target->t_data;
327 void *arg = (void *)mdb.m_nargs;
328 mdb_tgt_gregset_t gregs, *grp;
329
330 if (flags & DCMD_ADDRSPEC) {
331 bzero(&gregs, sizeof (gregs));
332 gregs.kregs[KREG_FP] = addr;
333 grp = &gregs;
334 } else
335 grp = kt->k_regs;
336
337 if (argc != 0) {
338 if (argv->a_type == MDB_TYPE_CHAR || argc > 1)
339 return (DCMD_USAGE);
340
341 if (argv->a_type == MDB_TYPE_STRING)
342 arg = (void *)(uint_t)mdb_strtoull(argv->a_un.a_str);
343 else
344 arg = (void *)(uint_t)argv->a_un.a_val;
345 }
346
347 (void) kt_stack_iter(mdb.m_target, grp, func, arg);
348 return (DCMD_OK);
349 }
350
351 static int
352 kt_stack(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
353 {
354 return (kt_stack_common(addr, flags, argc, argv, kt_frame));
355 }
356
357 static int
358 kt_stackv(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
359 {
360 return (kt_stack_common(addr, flags, argc, argv, kt_framev));
361 }
362
363 /*ARGSUSED*/
364 static int
365 kt_notsup(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
366 {
367 errno = EMDB_TGTNOTSUP;
368 return (DCMD_ERR);
369 }
370
371 const mdb_tgt_ops_t kt_sparcv7_ops = {
372 kt_setflags, /* t_setflags */
373 kt_setcontext, /* t_setcontext */
374 kt_activate, /* t_activate */
375 kt_deactivate, /* t_deactivate */
376 (void (*)()) mdb_tgt_nop, /* t_periodic */
377 kt_destroy, /* t_destroy */
378 kt_name, /* t_name */
379 (const char *(*)()) mdb_conf_isa, /* t_isa */
380 kt_platform, /* t_platform */
381 kt_uname, /* t_uname */
382 kt_dmodel, /* t_dmodel */
383 kt_aread, /* t_aread */
384 kt_awrite, /* t_awrite */
385 kt_vread, /* t_vread */
386 kt_vwrite, /* t_vwrite */
387 kt_pread, /* t_pread */
388 kt_pwrite, /* t_pwrite */
389 kt_fread, /* t_fread */
390 kt_fwrite, /* t_fwrite */
391 (ssize_t (*)()) mdb_tgt_notsup, /* t_ioread */
392 (ssize_t (*)()) mdb_tgt_notsup, /* t_iowrite */
393 kt_vtop, /* t_vtop */
394 kt_lookup_by_name, /* t_lookup_by_name */
395 kt_lookup_by_addr, /* t_lookup_by_addr */
396 kt_symbol_iter, /* t_symbol_iter */
397 kt_mapping_iter, /* t_mapping_iter */
398 kt_object_iter, /* t_object_iter */
399 kt_addr_to_map, /* t_addr_to_map */
400 kt_name_to_map, /* t_name_to_map */
401 kt_addr_to_ctf, /* t_addr_to_ctf */
402 kt_name_to_ctf, /* t_name_to_ctf */
403 kt_status, /* t_status */
404 (int (*)()) mdb_tgt_notsup, /* t_run */
405 (int (*)()) mdb_tgt_notsup, /* t_step */
406 (int (*)()) mdb_tgt_notsup, /* t_step_out */
407 (int (*)()) mdb_tgt_notsup, /* t_next */
408 (int (*)()) mdb_tgt_notsup, /* t_cont */
409 (int (*)()) mdb_tgt_notsup, /* t_signal */
410 (int (*)()) mdb_tgt_null, /* t_add_vbrkpt */
411 (int (*)()) mdb_tgt_null, /* t_add_sbrkpt */
412 (int (*)()) mdb_tgt_null, /* t_add_pwapt */
413 (int (*)()) mdb_tgt_null, /* t_add_vwapt */
414 (int (*)()) mdb_tgt_null, /* t_add_iowapt */
415 (int (*)()) mdb_tgt_null, /* t_add_sysenter */
416 (int (*)()) mdb_tgt_null, /* t_add_sysexit */
417 (int (*)()) mdb_tgt_null, /* t_add_signal */
418 (int (*)()) mdb_tgt_null, /* t_add_fault */
419 kt_getareg, /* t_getareg */
420 kt_putareg, /* t_putareg */
421 kt_stack_iter, /* t_stack_iter */
422 (int (*)()) mdb_tgt_notsup /* t_auxv */
423 };
424
425 void
426 kt_sparcv7_init(mdb_tgt_t *t)
427 {
428 kt_data_t *kt = t->t_data;
429
430 struct rwindow rwin;
431 panic_data_t pd;
432 label_t label;
433 kreg_t *kregs;
434
435 /*
436 * Initialize the machine-dependent parts of the kernel target
437 * structure. Once this is complete and we fill in the ops
438 * vector, the target is now fully constructed and we can use
439 * the target API itself to perform the rest of our initialization.
440 */
441 kt->k_rds = kt_sparcv7_regs;
442 kt->k_regs = mdb_zalloc(sizeof (mdb_tgt_gregset_t), UM_SLEEP);
443 kt->k_regsize = sizeof (mdb_tgt_gregset_t);
444 kt->k_dcmd_regs = kt_regs;
445 kt->k_dcmd_stack = kt_stack;
446 kt->k_dcmd_stackv = kt_stackv;
447 kt->k_dcmd_stackr = kt_stackv;
448 kt->k_dcmd_cpustack = kt_notsup;
449 kt->k_dcmd_cpuregs = kt_notsup;
450
451 t->t_ops = &kt_sparcv7_ops;
452 kregs = kt->k_regs->kregs;
453
454 (void) mdb_dis_select("v8");
455
456 /*
457 * Don't attempt to load any thread or register information if
458 * we're examining the live operating system.
459 */
460 if (strcmp(kt->k_symfile, "/dev/ksyms") == 0)
461 return;
462
463 /*
464 * If the panicbuf symbol is present and we can consume a panicbuf
465 * header of the appropriate version from this address, then
466 * we can initialize our current register set based on its contents:
467 */
468 if (mdb_tgt_readsym(t, MDB_TGT_AS_VIRT, &pd, sizeof (pd),
469 MDB_TGT_OBJ_EXEC, "panicbuf") == sizeof (pd) &&
470 pd.pd_version == PANICBUFVERS) {
471
472 size_t pd_size = MIN(PANICBUFSIZE, pd.pd_msgoff);
473 panic_data_t *pdp = mdb_zalloc(pd_size, UM_SLEEP);
474 uint_t i, n;
475
476 (void) mdb_tgt_readsym(t, MDB_TGT_AS_VIRT, pdp, pd_size,
477 MDB_TGT_OBJ_EXEC, "panicbuf");
478
479 n = (pd_size - (sizeof (panic_data_t) -
480 sizeof (panic_nv_t))) / sizeof (panic_nv_t);
481
482 for (i = 0; i < n; i++) {
483 (void) kt_putareg(t, kt->k_tid,
484 pdp->pd_nvdata[i].pnv_name,
485 pdp->pd_nvdata[i].pnv_value);
486 }
487
488 mdb_free(pdp, pd_size);
489 }
490
491 /*
492 * Prior to the re-structuring of panicbuf, our only register data
493 * was the panic_regs label_t, into which a setjmp() was performed.
494 */
495 if (kregs[KREG_PC] == 0 && kregs[KREG_SP] == 0 &&
496 mdb_tgt_readsym(t, MDB_TGT_AS_VIRT, &label, sizeof (label),
497 MDB_TGT_OBJ_EXEC, "panic_regs") == sizeof (label)) {
498
499 kregs[KREG_PC] = label.val[0];
500 kregs[KREG_SP] = label.val[1];
501 }
502
503 /*
504 * If we can read a saved register window from the stack at %sp,
505 * we can also fill in the locals and inputs.
506 */
507 if (kregs[KREG_SP] != 0 && mdb_tgt_vread(t, &rwin, sizeof (rwin),
508 kregs[KREG_SP]) == sizeof (rwin)) {
509
510 kregs[KREG_L0] = rwin.rw_local[0];
511 kregs[KREG_L1] = rwin.rw_local[1];
512 kregs[KREG_L2] = rwin.rw_local[2];
513 kregs[KREG_L3] = rwin.rw_local[3];
514 kregs[KREG_L4] = rwin.rw_local[4];
515 kregs[KREG_L5] = rwin.rw_local[5];
516 kregs[KREG_L6] = rwin.rw_local[6];
517 kregs[KREG_L7] = rwin.rw_local[7];
518
519 kregs[KREG_I0] = rwin.rw_in[0];
520 kregs[KREG_I1] = rwin.rw_in[1];
521 kregs[KREG_I2] = rwin.rw_in[2];
522 kregs[KREG_I3] = rwin.rw_in[3];
523 kregs[KREG_I4] = rwin.rw_in[4];
524 kregs[KREG_I5] = rwin.rw_in[5];
525 kregs[KREG_I6] = rwin.rw_in[6];
526 kregs[KREG_I7] = rwin.rw_in[7];
527
528 } else if (kregs[KREG_SP] != 0) {
529 warn("failed to read rwindow at %p -- current "
530 "frame inputs will be unavailable\n",
531 (void *)kregs[KREG_SP]);
532 }
533 }