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 Intel 32-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/regset.h>
37#include <sys/frame.h>
38#include <sys/stack.h>
39#include <sys/sysmacros.h>
40#include <sys/panic.h>
41#include <strings.h>
42
43#include <mdb/mdb_target_impl.h>
44#include <mdb/mdb_disasm.h>
45#include <mdb/mdb_modapi.h>
46#include <mdb/mdb_conf.h>
47#include <mdb/mdb_kreg_impl.h>
48#include <mdb/mdb_isautil.h>
49#include <mdb/mdb_ia32util.h>
50#include <mdb/kvm_isadep.h>
51#include <mdb/mdb_kvm.h>
52#include <mdb/mdb_err.h>
53#include <mdb/mdb_debug.h>
54#include <mdb/mdb.h>
55
56
57/*ARGSUSED*/
58int
59kt_regs(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
60{
61	mdb_ia32_printregs((const mdb_tgt_gregset_t *)addr);
62	return (DCMD_OK);
63}
64
65static int
66kt_stack_common(uintptr_t addr, uint_t flags, int argc,
67    const mdb_arg_t *argv, mdb_tgt_stack_f *func)
68{
69	kt_data_t *kt = mdb.m_target->t_data;
70	void *arg = (void *)mdb.m_nargs;
71	mdb_tgt_gregset_t gregs, *grp;
72
73	if (flags & DCMD_ADDRSPEC) {
74		bzero(&gregs, sizeof (gregs));
75		gregs.kregs[KREG_EBP] = addr;
76		grp = &gregs;
77	} else
78		grp = kt->k_regs;
79
80	if (argc != 0) {
81		if (argv->a_type == MDB_TYPE_CHAR || argc > 1)
82			return (DCMD_USAGE);
83
84		if (argv->a_type == MDB_TYPE_STRING)
85			arg = (void *)(uint_t)mdb_strtoull(argv->a_un.a_str);
86		else
87			arg = (void *)(uint_t)argv->a_un.a_val;
88	}
89
90	(void) mdb_ia32_kvm_stack_iter(mdb.m_target, grp, func, arg);
91	return (DCMD_OK);
92}
93
94int
95kt_stack(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
96{
97	return (kt_stack_common(addr, flags, argc, argv, mdb_ia32_kvm_frame));
98}
99
100int
101kt_stackv(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
102{
103	return (kt_stack_common(addr, flags, argc, argv, mdb_ia32_kvm_framev));
104}
105
106const mdb_tgt_ops_t kt_ia32_ops = {
107	kt_setflags,				/* t_setflags */
108	kt_setcontext,				/* t_setcontext */
109	kt_activate,				/* t_activate */
110	kt_deactivate,				/* t_deactivate */
111	(void (*)())(uintptr_t) mdb_tgt_nop,	/* t_periodic */
112	kt_destroy,				/* t_destroy */
113	kt_name,				/* t_name */
114	(const char *(*)()) mdb_conf_isa,	/* t_isa */
115	kt_platform,				/* t_platform */
116	kt_uname,				/* t_uname */
117	kt_dmodel,				/* t_dmodel */
118	kt_aread,				/* t_aread */
119	kt_awrite,				/* t_awrite */
120	kt_vread,				/* t_vread */
121	kt_vwrite,				/* t_vwrite */
122	kt_pread,				/* t_pread */
123	kt_pwrite,				/* t_pwrite */
124	kt_fread,				/* t_fread */
125	kt_fwrite,				/* t_fwrite */
126	(ssize_t (*)()) mdb_tgt_notsup,		/* t_ioread */
127	(ssize_t (*)()) mdb_tgt_notsup,		/* t_iowrite */
128	kt_vtop,				/* t_vtop */
129	kt_lookup_by_name,			/* t_lookup_by_name */
130	kt_lookup_by_addr,			/* t_lookup_by_addr */
131	kt_symbol_iter,				/* t_symbol_iter */
132	kt_mapping_iter,			/* t_mapping_iter */
133	kt_object_iter,				/* t_object_iter */
134	kt_addr_to_map,				/* t_addr_to_map */
135	kt_name_to_map,				/* t_name_to_map */
136	kt_addr_to_ctf,				/* t_addr_to_ctf */
137	kt_name_to_ctf,				/* t_name_to_ctf */
138	kt_status,				/* t_status */
139	(int (*)()) mdb_tgt_notsup,		/* t_run */
140	(int (*)()) mdb_tgt_notsup,		/* t_step */
141	(int (*)()) mdb_tgt_notsup,		/* t_step_out */
142	(int (*)()) mdb_tgt_notsup,		/* t_next */
143	(int (*)()) mdb_tgt_notsup,		/* t_cont */
144	(int (*)()) mdb_tgt_notsup,		/* t_signal */
145	(int (*)())(uintptr_t) mdb_tgt_null,	/* t_add_vbrkpt */
146	(int (*)())(uintptr_t) mdb_tgt_null,	/* t_add_sbrkpt */
147	(int (*)())(uintptr_t) mdb_tgt_null,	/* t_add_pwapt */
148	(int (*)())(uintptr_t) mdb_tgt_null,	/* t_add_vwapt */
149	(int (*)())(uintptr_t) mdb_tgt_null,	/* t_add_iowapt */
150	(int (*)())(uintptr_t) mdb_tgt_null,	/* t_add_sysenter */
151	(int (*)())(uintptr_t) mdb_tgt_null,	/* t_add_sysexit */
152	(int (*)())(uintptr_t) mdb_tgt_null,	/* t_add_signal */
153	(int (*)())(uintptr_t) mdb_tgt_null,	/* t_add_fault */
154	kt_getareg,				/* t_getareg */
155	kt_putareg,				/* t_putareg */
156	mdb_ia32_kvm_stack_iter,		/* t_stack_iter */
157	(int (*)()) mdb_tgt_notsup		/* t_auxv */
158};
159
160void
161kt_regs_to_kregs(struct regs *regs, mdb_tgt_gregset_t *gregs)
162{
163	gregs->kregs[KREG_SAVFP] = regs->r_savfp;
164	gregs->kregs[KREG_SAVPC] = regs->r_savpc;
165	gregs->kregs[KREG_EAX] = regs->r_eax;
166	gregs->kregs[KREG_EBX] = regs->r_ebx;
167	gregs->kregs[KREG_ECX] = regs->r_ecx;
168	gregs->kregs[KREG_EDX] = regs->r_edx;
169	gregs->kregs[KREG_ESI] = regs->r_esi;
170	gregs->kregs[KREG_EDI] = regs->r_edi;
171	gregs->kregs[KREG_EBP] = regs->r_ebp;
172	gregs->kregs[KREG_ESP] = regs->r_esp;
173	gregs->kregs[KREG_CS] = regs->r_cs;
174	gregs->kregs[KREG_DS] = regs->r_ds;
175	gregs->kregs[KREG_SS] = regs->r_ss;
176	gregs->kregs[KREG_ES] = regs->r_es;
177	gregs->kregs[KREG_FS] = regs->r_fs;
178	gregs->kregs[KREG_GS] = regs->r_gs;
179	gregs->kregs[KREG_EFLAGS] = regs->r_efl;
180	gregs->kregs[KREG_EIP] = regs->r_eip;
181	gregs->kregs[KREG_UESP] = regs->r_uesp;
182	gregs->kregs[KREG_TRAPNO] = regs->r_trapno;
183	gregs->kregs[KREG_ERR] = regs->r_err;
184}
185
186void
187kt_ia32_init(mdb_tgt_t *t)
188{
189	kt_data_t *kt = t->t_data;
190	panic_data_t pd;
191	label_t label;
192	struct regs regs;
193	kreg_t *kregs;
194	uintptr_t addr;
195
196	/*
197	 * Initialize the machine-dependent parts of the kernel target
198	 * structure.  Once this is complete and we fill in the ops
199	 * vector, the target is now fully constructed and we can use
200	 * the target API itself to perform the rest of our initialization.
201	 */
202	kt->k_rds = mdb_ia32_kregs;
203	kt->k_regs = mdb_zalloc(sizeof (mdb_tgt_gregset_t), UM_SLEEP);
204	kt->k_regsize = sizeof (mdb_tgt_gregset_t);
205	kt->k_dcmd_regs = kt_regs;
206	kt->k_dcmd_stack = kt_stack;
207	kt->k_dcmd_stackv = kt_stackv;
208	kt->k_dcmd_stackr = kt_stackv;
209	kt->k_dcmd_cpustack = kt_cpustack;
210	kt->k_dcmd_cpuregs = kt_cpuregs;
211
212	t->t_ops = &kt_ia32_ops;
213	kregs = kt->k_regs->kregs;
214
215	(void) mdb_dis_select("ia32");
216
217	/*
218	 * Lookup the symbols corresponding to subroutines in locore.s where
219	 * we expect a saved regs structure to be pushed on the stack.  When
220	 * performing stack tracebacks we will attempt to detect interrupt
221	 * frames by comparing the %eip value to these symbols.
222	 */
223	(void) mdb_tgt_lookup_by_name(t, MDB_TGT_OBJ_EXEC,
224	    "cmnint", &kt->k_intr_sym, NULL);
225
226	(void) mdb_tgt_lookup_by_name(t, MDB_TGT_OBJ_EXEC,
227	    "cmntrap", &kt->k_trap_sym, NULL);
228
229	/*
230	 * Don't attempt to load any thread or register information if
231	 * we're examining the live operating system.
232	 */
233	if (kt->k_symfile != NULL && strcmp(kt->k_symfile, "/dev/ksyms") == 0)
234		return;
235
236	/*
237	 * If the panicbuf symbol is present and we can consume a panicbuf
238	 * header of the appropriate version from this address, then we can
239	 * initialize our current register set based on its contents.
240	 * Prior to the re-structuring of panicbuf, our only register data
241	 * was the panic_regs label_t, into which a setjmp() was performed,
242	 * or the panic_reg register pointer, which was only non-zero if
243	 * the system panicked as a result of a trap calling die().
244	 */
245	if (mdb_tgt_readsym(t, MDB_TGT_AS_VIRT, &pd, sizeof (pd),
246	    MDB_TGT_OBJ_EXEC, "panicbuf") == sizeof (pd) &&
247	    pd.pd_version == PANICBUFVERS) {
248
249		size_t pd_size = MIN(PANICBUFSIZE, pd.pd_msgoff);
250		panic_data_t *pdp = mdb_zalloc(pd_size, UM_SLEEP);
251		uint_t i, n;
252
253		(void) mdb_tgt_readsym(t, MDB_TGT_AS_VIRT, pdp, pd_size,
254		    MDB_TGT_OBJ_EXEC, "panicbuf");
255
256		n = (pd_size - (sizeof (panic_data_t) -
257		    sizeof (panic_nv_t))) / sizeof (panic_nv_t);
258
259		for (i = 0; i < n; i++) {
260			(void) kt_putareg(t, kt->k_tid,
261			    pdp->pd_nvdata[i].pnv_name,
262			    pdp->pd_nvdata[i].pnv_value);
263		}
264
265		mdb_free(pdp, pd_size);
266
267		return;
268	}
269
270	if (mdb_tgt_readsym(t, MDB_TGT_AS_VIRT, &addr, sizeof (addr),
271	    MDB_TGT_OBJ_EXEC, "panic_reg") == sizeof (addr) && addr != 0 &&
272	    mdb_tgt_vread(t, &regs, sizeof (regs), addr) == sizeof (regs)) {
273		kt_regs_to_kregs(&regs, kt->k_regs);
274		return;
275	}
276
277	/*
278	 * If we can't read any panic regs, then our penultimate try is for any
279	 * CPU context that may have been stored (for example, in Xen core
280	 * dumps).  As this can only succeed for kernels with the above
281	 * methods available, we let it over-ride the older panic_regs method,
282	 * which will always manage to read the label_t, even if there's
283	 * nothing useful there.
284	 */
285	if (kt_kvmregs(t, 0, kt->k_regs) == 0)
286		return;
287
288	if (mdb_tgt_readsym(t, MDB_TGT_AS_VIRT, &label, sizeof (label),
289	    MDB_TGT_OBJ_EXEC, "panic_regs") == sizeof (label)) {
290		kregs[KREG_EDI] = label.val[0];
291		kregs[KREG_ESI] = label.val[1];
292		kregs[KREG_EBX] = label.val[2];
293		kregs[KREG_EBP] = label.val[3];
294		kregs[KREG_ESP] = label.val[4];
295		kregs[KREG_EIP] = label.val[5];
296		return;
297	}
298
299	warn("failed to read panicbuf, panic_reg and panic_regs -- "
300	    "current register set will be unavailable\n");
301}
302