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_ia32util.h>
49#include <mdb/kvm_isadep.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
56/*ARGSUSED*/
57int
58kt_regs(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
59{
60	mdb_ia32_printregs((const mdb_tgt_gregset_t *)addr);
61	return (DCMD_OK);
62}
63
64static int
65kt_stack_common(uintptr_t addr, uint_t flags, int argc,
66    const mdb_arg_t *argv, mdb_tgt_stack_f *func)
67{
68	kt_data_t *kt = mdb.m_target->t_data;
69	void *arg = (void *)mdb.m_nargs;
70	mdb_tgt_gregset_t gregs, *grp;
71
72	if (flags & DCMD_ADDRSPEC) {
73		bzero(&gregs, sizeof (gregs));
74		gregs.kregs[KREG_EBP] = addr;
75		grp = &gregs;
76	} else
77		grp = kt->k_regs;
78
79	if (argc != 0) {
80		if (argv->a_type == MDB_TYPE_CHAR || argc > 1)
81			return (DCMD_USAGE);
82
83		if (argv->a_type == MDB_TYPE_STRING)
84			arg = (void *)(uint_t)mdb_strtoull(argv->a_un.a_str);
85		else
86			arg = (void *)(uint_t)argv->a_un.a_val;
87	}
88
89	(void) mdb_ia32_kvm_stack_iter(mdb.m_target, grp, func, arg);
90	return (DCMD_OK);
91}
92
93int
94kt_stack(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
95{
96	return (kt_stack_common(addr, flags, argc, argv, mdb_ia32_kvm_frame));
97}
98
99int
100kt_stackv(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
101{
102	return (kt_stack_common(addr, flags, argc, argv, mdb_ia32_kvm_framev));
103}
104
105const mdb_tgt_ops_t kt_ia32_ops = {
106	kt_setflags,				/* t_setflags */
107	kt_setcontext,				/* t_setcontext */
108	kt_activate,				/* t_activate */
109	kt_deactivate,				/* t_deactivate */
110	(void (*)()) mdb_tgt_nop,		/* t_periodic */
111	kt_destroy,				/* t_destroy */
112	kt_name,				/* t_name */
113	(const char *(*)()) mdb_conf_isa,	/* t_isa */
114	kt_platform,				/* t_platform */
115	kt_uname,				/* t_uname */
116	kt_dmodel,				/* t_dmodel */
117	kt_aread,				/* t_aread */
118	kt_awrite,				/* t_awrite */
119	kt_vread,				/* t_vread */
120	kt_vwrite,				/* t_vwrite */
121	kt_pread,				/* t_pread */
122	kt_pwrite,				/* t_pwrite */
123	kt_fread,				/* t_fread */
124	kt_fwrite,				/* t_fwrite */
125	(ssize_t (*)()) mdb_tgt_notsup,		/* t_ioread */
126	(ssize_t (*)()) mdb_tgt_notsup,		/* t_iowrite */
127	kt_vtop,				/* t_vtop */
128	kt_lookup_by_name,			/* t_lookup_by_name */
129	kt_lookup_by_addr,			/* t_lookup_by_addr */
130	kt_symbol_iter,				/* t_symbol_iter */
131	kt_mapping_iter,			/* t_mapping_iter */
132	kt_object_iter,				/* t_object_iter */
133	kt_addr_to_map,				/* t_addr_to_map */
134	kt_name_to_map,				/* t_name_to_map */
135	kt_addr_to_ctf,				/* t_addr_to_ctf */
136	kt_name_to_ctf,				/* t_name_to_ctf */
137	kt_status,				/* t_status */
138	(int (*)()) mdb_tgt_notsup,		/* t_run */
139	(int (*)()) mdb_tgt_notsup,		/* t_step */
140	(int (*)()) mdb_tgt_notsup,		/* t_step_out */
141	(int (*)()) mdb_tgt_notsup,		/* t_next */
142	(int (*)()) mdb_tgt_notsup,		/* t_cont */
143	(int (*)()) mdb_tgt_notsup,		/* t_signal */
144	(int (*)()) mdb_tgt_null,		/* t_add_vbrkpt */
145	(int (*)()) mdb_tgt_null,		/* t_add_sbrkpt */
146	(int (*)()) mdb_tgt_null,		/* t_add_pwapt */
147	(int (*)()) mdb_tgt_null,		/* t_add_vwapt */
148	(int (*)()) mdb_tgt_null,		/* t_add_iowapt */
149	(int (*)()) mdb_tgt_null,		/* t_add_sysenter */
150	(int (*)()) mdb_tgt_null,		/* t_add_sysexit */
151	(int (*)()) mdb_tgt_null,		/* t_add_signal */
152	(int (*)()) mdb_tgt_null,		/* t_add_fault */
153	kt_getareg,				/* t_getareg */
154	kt_putareg,				/* t_putareg */
155	mdb_ia32_kvm_stack_iter,		/* t_stack_iter */
156	(int (*)()) mdb_tgt_notsup		/* t_auxv */
157};
158
159void
160kt_regs_to_kregs(struct regs *regs, mdb_tgt_gregset_t *gregs)
161{
162	gregs->kregs[KREG_SAVFP] = regs->r_savfp;
163	gregs->kregs[KREG_SAVPC] = regs->r_savpc;
164	gregs->kregs[KREG_EAX] = regs->r_eax;
165	gregs->kregs[KREG_EBX] = regs->r_ebx;
166	gregs->kregs[KREG_ECX] = regs->r_ecx;
167	gregs->kregs[KREG_EDX] = regs->r_edx;
168	gregs->kregs[KREG_ESI] = regs->r_esi;
169	gregs->kregs[KREG_EDI] = regs->r_edi;
170	gregs->kregs[KREG_EBP] = regs->r_ebp;
171	gregs->kregs[KREG_ESP] = regs->r_esp;
172	gregs->kregs[KREG_CS] = regs->r_cs;
173	gregs->kregs[KREG_DS] = regs->r_ds;
174	gregs->kregs[KREG_SS] = regs->r_ss;
175	gregs->kregs[KREG_ES] = regs->r_es;
176	gregs->kregs[KREG_FS] = regs->r_fs;
177	gregs->kregs[KREG_GS] = regs->r_gs;
178	gregs->kregs[KREG_EFLAGS] = regs->r_efl;
179	gregs->kregs[KREG_EIP] = regs->r_eip;
180	gregs->kregs[KREG_UESP] = regs->r_uesp;
181	gregs->kregs[KREG_TRAPNO] = regs->r_trapno;
182	gregs->kregs[KREG_ERR] = regs->r_err;
183}
184
185void
186kt_ia32_init(mdb_tgt_t *t)
187{
188	kt_data_t *kt = t->t_data;
189	panic_data_t pd;
190	label_t label;
191	struct regs regs;
192	kreg_t *kregs;
193	uintptr_t addr;
194
195	/*
196	 * Initialize the machine-dependent parts of the kernel target
197	 * structure.  Once this is complete and we fill in the ops
198	 * vector, the target is now fully constructed and we can use
199	 * the target API itself to perform the rest of our initialization.
200	 */
201	kt->k_rds = mdb_ia32_kregs;
202	kt->k_regs = mdb_zalloc(sizeof (mdb_tgt_gregset_t), UM_SLEEP);
203	kt->k_regsize = sizeof (mdb_tgt_gregset_t);
204	kt->k_dcmd_regs = kt_regs;
205	kt->k_dcmd_stack = kt_stack;
206	kt->k_dcmd_stackv = kt_stackv;
207	kt->k_dcmd_stackr = kt_stackv;
208	kt->k_dcmd_cpustack = kt_cpustack;
209	kt->k_dcmd_cpuregs = kt_cpuregs;
210
211	t->t_ops = &kt_ia32_ops;
212	kregs = kt->k_regs->kregs;
213
214	(void) mdb_dis_select("ia32");
215
216	/*
217	 * Lookup the symbols corresponding to subroutines in locore.s where
218	 * we expect a saved regs structure to be pushed on the stack.  When
219	 * performing stack tracebacks we will attempt to detect interrupt
220	 * frames by comparing the %eip value to these symbols.
221	 */
222	(void) mdb_tgt_lookup_by_name(t, MDB_TGT_OBJ_EXEC,
223	    "cmnint", &kt->k_intr_sym, NULL);
224
225	(void) mdb_tgt_lookup_by_name(t, MDB_TGT_OBJ_EXEC,
226	    "cmntrap", &kt->k_trap_sym, NULL);
227
228	/*
229	 * Don't attempt to load any thread or register information if
230	 * we're examining the live operating system.
231	 */
232	if (kt->k_symfile != NULL && strcmp(kt->k_symfile, "/dev/ksyms") == 0)
233		return;
234
235	/*
236	 * If the panicbuf symbol is present and we can consume a panicbuf
237	 * header of the appropriate version from this address, then we can
238	 * initialize our current register set based on its contents.
239	 * Prior to the re-structuring of panicbuf, our only register data
240	 * was the panic_regs label_t, into which a setjmp() was performed,
241	 * or the panic_reg register pointer, which was only non-zero if
242	 * the system panicked as a result of a trap calling die().
243	 */
244	if (mdb_tgt_readsym(t, MDB_TGT_AS_VIRT, &pd, sizeof (pd),
245	    MDB_TGT_OBJ_EXEC, "panicbuf") == sizeof (pd) &&
246	    pd.pd_version == PANICBUFVERS) {
247
248		size_t pd_size = MIN(PANICBUFSIZE, pd.pd_msgoff);
249		panic_data_t *pdp = mdb_zalloc(pd_size, UM_SLEEP);
250		uint_t i, n;
251
252		(void) mdb_tgt_readsym(t, MDB_TGT_AS_VIRT, pdp, pd_size,
253		    MDB_TGT_OBJ_EXEC, "panicbuf");
254
255		n = (pd_size - (sizeof (panic_data_t) -
256		    sizeof (panic_nv_t))) / sizeof (panic_nv_t);
257
258		for (i = 0; i < n; i++) {
259			(void) kt_putareg(t, kt->k_tid,
260			    pdp->pd_nvdata[i].pnv_name,
261			    pdp->pd_nvdata[i].pnv_value);
262		}
263
264		mdb_free(pdp, pd_size);
265
266		return;
267	}
268
269	if (mdb_tgt_readsym(t, MDB_TGT_AS_VIRT, &addr, sizeof (addr),
270	    MDB_TGT_OBJ_EXEC, "panic_reg") == sizeof (addr) && addr != 0 &&
271	    mdb_tgt_vread(t, &regs, sizeof (regs), addr) == sizeof (regs)) {
272		kt_regs_to_kregs(&regs, kt->k_regs);
273		return;
274	}
275
276	/*
277	 * If we can't read any panic regs, then our penultimate try is for any
278	 * CPU context that may have been stored (for example, in Xen core
279	 * dumps).  As this can only succeed for kernels with the above
280	 * methods available, we let it over-ride the older panic_regs method,
281	 * which will always manage to read the label_t, even if there's
282	 * nothing useful there.
283	 */
284	if (kt_kvmregs(t, 0, kt->k_regs) == 0)
285		return;
286
287	if (mdb_tgt_readsym(t, MDB_TGT_AS_VIRT, &label, sizeof (label),
288	    MDB_TGT_OBJ_EXEC, "panic_regs") == sizeof (label)) {
289		kregs[KREG_EDI] = label.val[0];
290		kregs[KREG_ESI] = label.val[1];
291		kregs[KREG_EBX] = label.val[2];
292		kregs[KREG_EBP] = label.val[3];
293		kregs[KREG_ESP] = label.val[4];
294		kregs[KREG_EIP] = label.val[5];
295		return;
296	}
297
298	warn("failed to read panicbuf, panic_reg and panic_regs -- "
299	    "current register set will be unavailable\n");
300}
301