xref: /titanic_44/usr/src/cmd/mdb/intel/mdb/kvm_amd64dep.c (revision 40e5e17b3361b3eea56a9723071c406894a20b78)
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  * Libkvm Kernel Target Intel 64-bit 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/reg.h>
37 #include <sys/frame.h>
38 #include <sys/stack.h>
39 #include <sys/sysmacros.h>
40 #include <sys/panic.h>
41 #include <sys/privregs.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_impl.h>
49 #include <mdb/mdb_amd64util.h>
50 #include <mdb/mdb_kvm.h>
51 #include <mdb/mdb_err.h>
52 #include <mdb/mdb_debug.h>
53 #include <mdb/mdb.h>
54 
55 static int
56 kt_getareg(mdb_tgt_t *t, mdb_tgt_tid_t tid,
57     const char *rname, mdb_tgt_reg_t *rp)
58 {
59 	const mdb_tgt_regdesc_t *rdp;
60 	kt_data_t *kt = t->t_data;
61 
62 	if (tid != kt->k_tid)
63 		return (set_errno(EMDB_NOREGS));
64 
65 	for (rdp = kt->k_rds; rdp->rd_name != NULL; rdp++) {
66 		if (strcmp(rname, rdp->rd_name) == 0) {
67 			*rp = kt->k_regs->kregs[rdp->rd_num];
68 			return (0);
69 		}
70 	}
71 
72 	return (set_errno(EMDB_BADREG));
73 }
74 
75 static int
76 kt_putareg(mdb_tgt_t *t, mdb_tgt_tid_t tid, const char *rname, mdb_tgt_reg_t r)
77 {
78 	const mdb_tgt_regdesc_t *rdp;
79 	kt_data_t *kt = t->t_data;
80 
81 	if (tid != kt->k_tid)
82 		return (set_errno(EMDB_NOREGS));
83 
84 	for (rdp = kt->k_rds; rdp->rd_name != NULL; rdp++) {
85 		if (strcmp(rname, rdp->rd_name) == 0) {
86 			kt->k_regs->kregs[rdp->rd_num] = (kreg_t)r;
87 			return (0);
88 		}
89 	}
90 
91 	return (set_errno(EMDB_BADREG));
92 }
93 
94 /*ARGSUSED*/
95 int
96 kt_regs(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
97 {
98 	kt_data_t *kt = mdb.m_target->t_data;
99 
100 	if (argc != 0 || (flags & DCMD_ADDRSPEC))
101 		return (DCMD_USAGE);
102 
103 	mdb_amd64_printregs(kt->k_regs);
104 
105 	return (DCMD_OK);
106 }
107 
108 /*
109  * Return a flag indicating if the specified %eip is likely to have an
110  * interrupt frame on the stack.  We do this by comparing the address to the
111  * range of addresses spanned by several well-known routines, and looking
112  * to see if the next and previous %ebp values are "far" apart.  Sigh.
113  */
114 int
115 mdb_kvm_intrframe(mdb_tgt_t *t, uintptr_t pc, uintptr_t fp,
116     uintptr_t prevfp)
117 {
118 	kt_data_t *kt = t->t_data;
119 
120 	return ((pc >= kt->k_intr_sym.st_value &&
121 	    (pc < kt->k_intr_sym.st_value + kt->k_intr_sym.st_size)) ||
122 	    (pc >= kt->k_trap_sym.st_value &&
123 	    (pc < kt->k_trap_sym.st_value + kt->k_trap_sym.st_size)) ||
124 	    (fp >= prevfp + 0x2000) || (fp <= prevfp - 0x2000));
125 }
126 
127 static int
128 kt_stack_common(uintptr_t addr, uint_t flags, int argc,
129     const mdb_arg_t *argv, mdb_tgt_stack_f *func)
130 {
131 	kt_data_t *kt = mdb.m_target->t_data;
132 	void *arg = (void *)(uintptr_t)mdb.m_nargs;
133 	mdb_tgt_gregset_t gregs, *grp;
134 
135 	if (flags & DCMD_ADDRSPEC) {
136 		bzero(&gregs, sizeof (gregs));
137 		gregs.kregs[KREG_RBP] = addr;
138 		grp = &gregs;
139 	} else
140 		grp = kt->k_regs;
141 
142 	if (argc != 0) {
143 		if (argv->a_type == MDB_TYPE_CHAR || argc > 1)
144 			return (DCMD_USAGE);
145 
146 		if (argv->a_type == MDB_TYPE_STRING)
147 			arg = (void *)mdb_strtoull(argv->a_un.a_str);
148 		else
149 			arg = (void *)argv->a_un.a_val;
150 	}
151 
152 	(void) mdb_amd64_kvm_stack_iter(mdb.m_target, grp, func, arg);
153 	return (DCMD_OK);
154 }
155 
156 static int
157 kt_stack(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
158 {
159 	return (kt_stack_common(addr, flags, argc, argv, mdb_amd64_kvm_frame));
160 }
161 
162 static int
163 kt_stackv(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
164 {
165 	return (kt_stack_common(addr, flags, argc, argv, mdb_amd64_kvm_framev));
166 }
167 
168 const mdb_tgt_ops_t kt_amd64_ops = {
169 	kt_setflags,				/* t_setflags */
170 	kt_setcontext,				/* t_setcontext */
171 	kt_activate,				/* t_activate */
172 	kt_deactivate,				/* t_deactivate */
173 	(void (*)()) mdb_tgt_nop,		/* t_periodic */
174 	kt_destroy,				/* t_destroy */
175 	kt_name,				/* t_name */
176 	(const char *(*)()) mdb_conf_isa,	/* t_isa */
177 	kt_platform,				/* t_platform */
178 	kt_uname,				/* t_uname */
179 	kt_dmodel,				/* t_dmodel */
180 	kt_aread,				/* t_aread */
181 	kt_awrite,				/* t_awrite */
182 	kt_vread,				/* t_vread */
183 	kt_vwrite,				/* t_vwrite */
184 	kt_pread,				/* t_pread */
185 	kt_pwrite,				/* t_pwrite */
186 	kt_fread,				/* t_fread */
187 	kt_fwrite,				/* t_fwrite */
188 	(ssize_t (*)()) mdb_tgt_notsup,		/* t_ioread */
189 	(ssize_t (*)()) mdb_tgt_notsup,		/* t_iowrite */
190 	kt_vtop,				/* t_vtop */
191 	kt_lookup_by_name,			/* t_lookup_by_name */
192 	kt_lookup_by_addr,			/* t_lookup_by_addr */
193 	kt_symbol_iter,				/* t_symbol_iter */
194 	kt_mapping_iter,			/* t_mapping_iter */
195 	kt_object_iter,				/* t_object_iter */
196 	kt_addr_to_map,				/* t_addr_to_map */
197 	kt_name_to_map,				/* t_name_to_map */
198 	kt_addr_to_ctf,				/* t_addr_to_ctf */
199 	kt_name_to_ctf,				/* t_name_to_ctf */
200 	kt_status,				/* t_status */
201 	(int (*)()) mdb_tgt_notsup,		/* t_run */
202 	(int (*)()) mdb_tgt_notsup,		/* t_step */
203 	(int (*)()) mdb_tgt_notsup,		/* t_step_out */
204 	(int (*)()) mdb_tgt_notsup,		/* t_step_branch */
205 	(int (*)()) mdb_tgt_notsup,		/* t_next */
206 	(int (*)()) mdb_tgt_notsup,		/* t_cont */
207 	(int (*)()) mdb_tgt_notsup,		/* t_signal */
208 	(int (*)()) mdb_tgt_null,		/* t_add_vbrkpt */
209 	(int (*)()) mdb_tgt_null,		/* t_add_sbrkpt */
210 	(int (*)()) mdb_tgt_null,		/* t_add_pwapt */
211 	(int (*)()) mdb_tgt_null,		/* t_add_vwapt */
212 	(int (*)()) mdb_tgt_null,		/* t_add_iowapt */
213 	(int (*)()) mdb_tgt_null,		/* t_add_sysenter */
214 	(int (*)()) mdb_tgt_null,		/* t_add_sysexit */
215 	(int (*)()) mdb_tgt_null,		/* t_add_signal */
216 	(int (*)()) mdb_tgt_null,		/* t_add_fault */
217 	kt_getareg,				/* t_getareg */
218 	kt_putareg,				/* t_putareg */
219 	mdb_amd64_kvm_stack_iter,		/* t_stack_iter */
220 };
221 
222 void
223 kt_amd64_init(mdb_tgt_t *t)
224 {
225 	kt_data_t *kt = t->t_data;
226 
227 	panic_data_t pd;
228 	kreg_t *kregs;
229 	struct regs regs;
230 	uintptr_t addr;
231 
232 	/*
233 	 * Initialize the machine-dependent parts of the kernel target
234 	 * structure.  Once this is complete and we fill in the ops
235 	 * vector, the target is now fully constructed and we can use
236 	 * the target API itself to perform the rest of our initialization.
237 	 */
238 	kt->k_rds = mdb_amd64_kregs;
239 	kt->k_regs = mdb_zalloc(sizeof (mdb_tgt_gregset_t), UM_SLEEP);
240 	kt->k_regsize = sizeof (mdb_tgt_gregset_t);
241 	kt->k_dcmd_regs = kt_regs;
242 	kt->k_dcmd_stack = kt_stack;
243 	kt->k_dcmd_stackv = kt_stackv;
244 	kt->k_dcmd_stackr = kt_stackv;
245 
246 	t->t_ops = &kt_amd64_ops;
247 	kregs = kt->k_regs->kregs;
248 
249 	(void) mdb_dis_select("amd64");
250 
251 	/*
252 	 * Lookup the symbols corresponding to subroutines in locore.s where
253 	 * we expect a saved regs structure to be pushed on the stack.  When
254 	 * performing stack tracebacks we will attempt to detect interrupt
255 	 * frames by comparing the %eip value to these symbols.
256 	 */
257 	(void) mdb_tgt_lookup_by_name(t, MDB_TGT_OBJ_EXEC,
258 	    "cmnint", &kt->k_intr_sym, NULL);
259 
260 	(void) mdb_tgt_lookup_by_name(t, MDB_TGT_OBJ_EXEC,
261 	    "cmntrap", &kt->k_trap_sym, NULL);
262 
263 	/*
264 	 * Don't attempt to load any thread or register information if
265 	 * we're examining the live operating system.
266 	 */
267 	if (strcmp(kt->k_symfile, "/dev/ksyms") == 0)
268 		return;
269 
270 	/*
271 	 * If the panicbuf symbol is present and we can consume a panicbuf
272 	 * header of the appropriate version from this address, then we can
273 	 * initialize our current register set based on its contents.
274 	 * Prior to the re-structuring of panicbuf, our only register data
275 	 * was the panic_regs label_t, into which a setjmp() was performed,
276 	 * or the panic_reg register pointer, which was only non-zero if
277 	 * the system panicked as a result of a trap calling die().
278 	 */
279 	if (mdb_tgt_readsym(t, MDB_TGT_AS_VIRT, &pd, sizeof (pd),
280 	    MDB_TGT_OBJ_EXEC, "panicbuf") == sizeof (pd) &&
281 	    pd.pd_version == PANICBUFVERS) {
282 
283 		size_t pd_size = MIN(PANICBUFSIZE, pd.pd_msgoff);
284 		panic_data_t *pdp = mdb_zalloc(pd_size, UM_SLEEP);
285 		uint_t i, n;
286 
287 		(void) mdb_tgt_readsym(t, MDB_TGT_AS_VIRT, pdp, pd_size,
288 		    MDB_TGT_OBJ_EXEC, "panicbuf");
289 
290 		n = (pd_size - (sizeof (panic_data_t) -
291 		    sizeof (panic_nv_t))) / sizeof (panic_nv_t);
292 
293 		for (i = 0; i < n; i++) {
294 			(void) kt_putareg(t, kt->k_tid,
295 			    pdp->pd_nvdata[i].pnv_name,
296 			    pdp->pd_nvdata[i].pnv_value);
297 		}
298 
299 		mdb_free(pdp, pd_size);
300 
301 	} else if (mdb_tgt_readsym(t, MDB_TGT_AS_VIRT, &addr, sizeof (addr),
302 	    MDB_TGT_OBJ_EXEC, "panic_reg") == sizeof (addr) && addr != NULL &&
303 	    mdb_tgt_vread(t, &regs, sizeof (regs), addr) == sizeof (regs)) {
304 
305 		kregs[KREG_SAVFP] = regs.r_savfp;
306 		kregs[KREG_SAVPC] = regs.r_savpc;
307 		kregs[KREG_RDI] = regs.r_rdi;
308 		kregs[KREG_RSI] = regs.r_rsi;
309 		kregs[KREG_RDX] = regs.r_rdx;
310 		kregs[KREG_RCX] = regs.r_rcx;
311 		kregs[KREG_R8] = regs.r_r8;
312 		kregs[KREG_R9] = regs.r_r9;
313 		kregs[KREG_RAX] = regs.r_rax;
314 		kregs[KREG_RBX] = regs.r_rbx;
315 		kregs[KREG_RBP] = regs.r_rbp;
316 		kregs[KREG_R10] = regs.r_r10;
317 		kregs[KREG_R11] = regs.r_r11;
318 		kregs[KREG_R12] = regs.r_r12;
319 		kregs[KREG_R13] = regs.r_r13;
320 		kregs[KREG_R14] = regs.r_r14;
321 		kregs[KREG_R15] = regs.r_r15;
322 		kregs[KREG_DS] = regs.r_ds;
323 		kregs[KREG_ES] = regs.r_es;
324 		kregs[KREG_FS] = regs.r_fs;
325 		kregs[KREG_GS] = regs.r_gs;
326 		kregs[KREG_TRAPNO] = regs.r_trapno;
327 		kregs[KREG_ERR] = regs.r_err;
328 		kregs[KREG_RIP] = regs.r_rip;
329 		kregs[KREG_CS] = regs.r_cs;
330 		kregs[KREG_RFLAGS] = regs.r_rfl;
331 		kregs[KREG_RSP] = regs.r_rsp;
332 		kregs[KREG_SS] = regs.r_ss;
333 
334 	} else {
335 		warn("failed to read panicbuf and panic_reg -- "
336 		    "current register set will be unavailable\n");
337 	}
338 }
339