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/tmp/gdb-8.1/gdb/amd64-fbsd-nat.c
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1 /* Native-dependent code for FreeBSD/amd64.
2
3 Copyright (C) 2003-2018 Free Software Foundation, Inc.
4
5 This file is part of GDB.
6
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 3 of the License, or
10 (at your option) any later version.
11
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
16
17 You should have received a copy of the GNU General Public License
18 along with this program. If not, see <http://www.gnu.org/licenses/>. */
19
20 #include "defs.h"
21 #include "inferior.h"
22 #include "regcache.h"
23 #include "target.h"
24
25 #include <signal.h>
26 #include <sys/types.h>
27 #include <sys/ptrace.h>
28 #include <sys/sysctl.h>
29 #include <sys/user.h>
30 #include <machine/reg.h>
31
32 #include "fbsd-nat.h"
33 #include "amd64-tdep.h"
34 #include "amd64-nat.h"
35 #include "x86-bsd-nat.h"
36 #include "x86-nat.h"
37 #include "x86-xstate.h"
38
39
40 /* Offset in `struct reg' where MEMBER is stored. */
41 #define REG_OFFSET(member) offsetof (struct reg, member)
42
43 /* At amd64fbsd64_r_reg_offset[REGNUM] you'll find the offset in
44 `struct reg' location where the GDB register REGNUM is stored.
45 Unsupported registers are marked with `-1'. */
46 static int amd64fbsd64_r_reg_offset[] =
47 {
48 REG_OFFSET (r_rax),
49 REG_OFFSET (r_rbx),
50 REG_OFFSET (r_rcx),
51 REG_OFFSET (r_rdx),
52 REG_OFFSET (r_rsi),
53 REG_OFFSET (r_rdi),
54 REG_OFFSET (r_rbp),
55 REG_OFFSET (r_rsp),
56 REG_OFFSET (r_r8),
57 REG_OFFSET (r_r9),
58 REG_OFFSET (r_r10),
59 REG_OFFSET (r_r11),
60 REG_OFFSET (r_r12),
61 REG_OFFSET (r_r13),
62 REG_OFFSET (r_r14),
63 REG_OFFSET (r_r15),
64 REG_OFFSET (r_rip),
65 REG_OFFSET (r_rflags),
66 REG_OFFSET (r_cs),
67 REG_OFFSET (r_ss),
68 -1,
69 -1,
70 -1,
71 -1
72 };
73
74
75 /* Mapping between the general-purpose registers in FreeBSD/amd64
76 `struct reg' format and GDB's register cache layout for
77 FreeBSD/i386.
78
79 Note that most FreeBSD/amd64 registers are 64-bit, while the
80 FreeBSD/i386 registers are all 32-bit, but since we're
81 little-endian we get away with that. */
82
83 /* From <machine/reg.h>. */
84 static int amd64fbsd32_r_reg_offset[I386_NUM_GREGS] =
85 {
86 14 * 8, 13 * 8, /* %eax, %ecx */
87 12 * 8, 11 * 8, /* %edx, %ebx */
88 20 * 8, 10 * 8, /* %esp, %ebp */
89 9 * 8, 8 * 8, /* %esi, %edi */
90 17 * 8, 19 * 8, /* %eip, %eflags */
91 18 * 8, 21 * 8, /* %cs, %ss */
92 -1, -1, -1, -1 /* %ds, %es, %fs, %gs */
93 };
94
95
96 /* Support for debugging kernel virtual memory images. */
97
98 #include <machine/pcb.h>
99 #include <osreldate.h>
100
101 #include "bsd-kvm.h"
102
103 static int
104 amd64fbsd_supply_pcb (struct regcache *regcache, struct pcb *pcb)
105 {
106 /* The following is true for FreeBSD 5.2:
107
108 The pcb contains %rip, %rbx, %rsp, %rbp, %r12, %r13, %r14, %r15,
109 %ds, %es, %fs and %gs. This accounts for all callee-saved
110 registers specified by the psABI and then some. Here %esp
111 contains the stack pointer at the point just after the call to
112 cpu_switch(). From this information we reconstruct the register
113 state as it would like when we just returned from cpu_switch(). */
114
115 /* The stack pointer shouldn't be zero. */
116 if (pcb->pcb_rsp == 0)
117 return 0;
118
119 pcb->pcb_rsp += 8;
120 regcache_raw_supply (regcache, AMD64_RIP_REGNUM, &pcb->pcb_rip);
121 regcache_raw_supply (regcache, AMD64_RBX_REGNUM, &pcb->pcb_rbx);
122 regcache_raw_supply (regcache, AMD64_RSP_REGNUM, &pcb->pcb_rsp);
123 regcache_raw_supply (regcache, AMD64_RBP_REGNUM, &pcb->pcb_rbp);
124 regcache_raw_supply (regcache, 12, &pcb->pcb_r12);
125 regcache_raw_supply (regcache, 13, &pcb->pcb_r13);
126 regcache_raw_supply (regcache, 14, &pcb->pcb_r14);
127 regcache_raw_supply (regcache, 15, &pcb->pcb_r15);
128 #if (__FreeBSD_version < 800075) && (__FreeBSD_kernel_version < 800075)
129 /* struct pcb provides the pcb_ds/pcb_es/pcb_fs/pcb_gs fields only
130 up until __FreeBSD_version 800074: The removal of these fields
131 occurred on 2009-04-01 while the __FreeBSD_version number was
132 bumped to 800075 on 2009-04-06. So 800075 is the closest version
133 number where we should not try to access these fields. */
134 regcache_raw_supply (regcache, AMD64_DS_REGNUM, &pcb->pcb_ds);
135 regcache_raw_supply (regcache, AMD64_ES_REGNUM, &pcb->pcb_es);
136 regcache_raw_supply (regcache, AMD64_FS_REGNUM, &pcb->pcb_fs);
137 regcache_raw_supply (regcache, AMD64_GS_REGNUM, &pcb->pcb_gs);
138 #endif
139
140 return 1;
141 }
142
143
144 /* Implement the to_read_description method. */
145
146 static const struct target_desc *
147 amd64fbsd_read_description (struct target_ops *ops)
148 {
149 #ifdef PT_GETXSTATE_INFO
150 static int xsave_probed;
151 static uint64_t xcr0;
152 #endif
153 struct reg regs;
154 int is64;
155
156 if (ptrace (PT_GETREGS, ptid_get_pid (inferior_ptid),
157 (PTRACE_TYPE_ARG3) &regs, 0) == -1)
158 perror_with_name (_("Couldn't get registers"));
159 is64 = (regs.r_cs == GSEL (GUCODE_SEL, SEL_UPL));
160 #ifdef PT_GETXSTATE_INFO
161 if (!xsave_probed)
162 {
163 struct ptrace_xstate_info info;
164
165 if (ptrace (PT_GETXSTATE_INFO, ptid_get_pid (inferior_ptid),
166 (PTRACE_TYPE_ARG3) &info, sizeof (info)) == 0)
167 {
168 x86bsd_xsave_len = info.xsave_len;
169 xcr0 = info.xsave_mask;
170 }
171 xsave_probed = 1;
172 }
173
174 if (x86bsd_xsave_len != 0)
175 {
176 if (is64)
177 return amd64_target_description (xcr0);
178 else
179 return i386_target_description (xcr0);
180 }
181 #endif
182 if (is64)
183 return amd64_target_description (X86_XSTATE_SSE_MASK);
184 else
185 return i386_target_description (X86_XSTATE_SSE_MASK);
186 }
187
188 void
189 _initialize_amd64fbsd_nat (void)
190 {
191 struct target_ops *t;
192 int offset;
193
194 amd64_native_gregset32_reg_offset = amd64fbsd32_r_reg_offset;
195 amd64_native_gregset64_reg_offset = amd64fbsd64_r_reg_offset;
196
197 /* Add some extra features to the common *BSD/i386 target. */
198 t = amd64bsd_target ();
199 t->to_read_description = amd64fbsd_read_description;
200
201 fbsd_nat_add_target (t);
202
203 /* Support debugging kernel virtual memory images. */
204 bsd_kvm_add_target (amd64fbsd_supply_pcb);
205
206 /* To support the recognition of signal handlers, i386-bsd-tdep.c
207 hardcodes some constants. Inclusion of this file means that we
208 are compiling a native debugger, which means that we can use the
209 system header files and sysctl(3) to get at the relevant
210 information. */
211
212 #define SC_REG_OFFSET amd64fbsd_sc_reg_offset
213
214 /* We only check the program counter, stack pointer and frame
215 pointer since these members of `struct sigcontext' are essential
216 for providing backtraces. */
217
218 #define SC_RIP_OFFSET SC_REG_OFFSET[AMD64_RIP_REGNUM]
219 #define SC_RSP_OFFSET SC_REG_OFFSET[AMD64_RSP_REGNUM]
220 #define SC_RBP_OFFSET SC_REG_OFFSET[AMD64_RBP_REGNUM]
221
222 /* Override the default value for the offset of the program counter
223 in the sigcontext structure. */
224 offset = offsetof (struct sigcontext, sc_rip);
225
226 if (SC_RIP_OFFSET != offset)
227 {
228 warning (_("\
229 offsetof (struct sigcontext, sc_rip) yields %d instead of %d.\n\
230 Please report this to <bug-gdb@gnu.org>."),
231 offset, SC_RIP_OFFSET);
232 }
233
234 SC_RIP_OFFSET = offset;
235
236 /* Likewise for the stack pointer. */
237 offset = offsetof (struct sigcontext, sc_rsp);
238
239 if (SC_RSP_OFFSET != offset)
240 {
241 warning (_("\
242 offsetof (struct sigcontext, sc_rsp) yields %d instead of %d.\n\
243 Please report this to <bug-gdb@gnu.org>."),
244 offset, SC_RSP_OFFSET);
245 }
246
247 SC_RSP_OFFSET = offset;
248
249 /* And the frame pointer. */
250 offset = offsetof (struct sigcontext, sc_rbp);
251
252 if (SC_RBP_OFFSET != offset)
253 {
254 warning (_("\
255 offsetof (struct sigcontext, sc_rbp) yields %d instead of %d.\n\
256 Please report this to <bug-gdb@gnu.org>."),
257 offset, SC_RBP_OFFSET);
258 }
259
260 SC_RBP_OFFSET = offset;
261
262 #ifdef KERN_PROC_SIGTRAMP
263 /* Normally signal frames are detected via amd64fbsd_sigtramp_p.
264 However, FreeBSD 9.2 through 10.1 do not include the page holding
265 the signal code in core dumps. These releases do provide a
266 kern.proc.sigtramp.<pid> sysctl that returns the location of the
267 signal trampoline for a running process. We fetch the location
268 of the current (gdb) process and use this to identify signal
269 frames in core dumps from these releases. Note that this only
270 works for core dumps of 64-bit (FreeBSD/amd64) processes and does
271 not handle core dumps of 32-bit (FreeBSD/i386) processes. */
272 {
273 int mib[4];
274 struct kinfo_sigtramp kst;
275 size_t len;
276
277 mib[0] = CTL_KERN;
278 mib[1] = KERN_PROC;
279 mib[2] = KERN_PROC_SIGTRAMP;
280 mib[3] = getpid ();
281 len = sizeof (kst);
282 if (sysctl (mib, 4, &kst, &len, NULL, 0) == 0)
283 {
284 amd64fbsd_sigtramp_start_addr = (uintptr_t) kst.ksigtramp_start;
285 amd64fbsd_sigtramp_end_addr = (uintptr_t) kst.ksigtramp_end;
286 }
287 }
288 #endif
289 }
amd64fbsd_sigtramp_start_addr
CORE_ADDR amd64fbsd_sigtramp_start_addr
Definition: amd64-fbsd-tdep.c:120
I386_NUM_GREGS
#define I386_NUM_GREGS
Definition: i386-tdep.h:332
target_ops::to_read_description
const struct target_desc *(* to_read_description)(struct target_ops *ops) TARGET_DEFAULT_RETURN(NULL)
Definition: target.h:790
REG_OFFSET
#define REG_OFFSET(member)
Definition: amd64-fbsd-nat.c:41
X86_XSTATE_SSE_MASK
#define X86_XSTATE_SSE_MASK
Definition: x86-xstate.h:42
amd64-nat.h
ptid_get_pid
int ptid_get_pid(const ptid_t &ptid)
Definition: ptid.c:47
AMD64_RBX_REGNUM
Definition: amd64-tdep.h:35
fbsd_nat_add_target
void fbsd_nat_add_target(struct target_ops *t)
Definition: fbsd-nat.c:1180
AMD64_RIP_REGNUM
Definition: amd64-tdep.h:50
amd64fbsd_supply_pcb
static int amd64fbsd_supply_pcb(struct regcache *regcache, struct pcb *pcb)
Definition: amd64-fbsd-nat.c:104
warning
void warning(const char *fmt,...)
Definition: errors.c:26
AMD64_FS_REGNUM
Definition: amd64-tdep.h:56
amd64fbsd_sigtramp_end_addr
CORE_ADDR amd64fbsd_sigtramp_end_addr
Definition: amd64-fbsd-tdep.c:121
x86-xstate.h
_
#define _(String)
Definition: gdb_locale.h:35
defs.h
x86-bsd-nat.h
ptrace
PTRACE_TYPE_RET ptrace()
SC_RIP_OFFSET
#define SC_RIP_OFFSET
AMD64_ES_REGNUM
Definition: amd64-tdep.h:55
amd64_native_gregset32_reg_offset
int * amd64_native_gregset32_reg_offset
Definition: amd64-nat.c:41
amd64fbsd32_r_reg_offset
static int amd64fbsd32_r_reg_offset[I386_NUM_GREGS]
Definition: amd64-fbsd-nat.c:84
target_ops
Definition: target.h:412
amd64_native_gregset64_reg_offset
int * amd64_native_gregset64_reg_offset
Definition: amd64-nat.c:45
regcache.h
fbsd-nat.h
bsd-kvm.h
AMD64_DS_REGNUM
Definition: amd64-tdep.h:54
inferior.h
AMD64_RSP_REGNUM
Definition: amd64-tdep.h:41
x86-nat.h
_initialize_amd64fbsd_nat
void _initialize_amd64fbsd_nat(void)
Definition: amd64-fbsd-nat.c:189
AMD64_GS_REGNUM
Definition: amd64-tdep.h:57
amd64-tdep.h
amd64fbsd64_r_reg_offset
static int amd64fbsd64_r_reg_offset[]
Definition: amd64-fbsd-nat.c:46
reg
Definition: regdef.h:22
SC_RBP_OFFSET
#define SC_RBP_OFFSET
AMD64_RBP_REGNUM
Definition: amd64-tdep.h:40
perror_with_name
void void void void void void void void void perror_with_name(const char *string) ATTRIBUTE_NORETURN
Definition: utils.c:692
amd64bsd_target
struct target_ops * amd64bsd_target(void)
Definition: amd64-bsd-nat.c:201
target_desc
Definition: target-descriptions.c:591
inferior_ptid
ptid_t inferior_ptid
Definition: infcmd.c:94
x86bsd_xsave_len
size_t x86bsd_xsave_len
offset
int offset
Definition: agent.c:65
target.h
regcache_raw_supply
void regcache_raw_supply(struct regcache *regcache, int regnum, const void *buf)
Definition: regcache.c:1004
regcache
Definition: regcache.h:232
PTRACE_TYPE_ARG3
#define PTRACE_TYPE_ARG3
Definition: config.h:642
bsd_kvm_add_target
void bsd_kvm_add_target(int(*supply_pcb)(struct regcache *, struct pcb *))
Definition: bsd-kvm.c:354
amd64fbsd_read_description
static const struct target_desc * amd64fbsd_read_description(struct target_ops *ops)
Definition: amd64-fbsd-nat.c:147
amd64_target_description
const struct target_desc * amd64_target_description(uint64_t xcr0)
Definition: amd64-tdep.c:3246
SC_RSP_OFFSET
#define SC_RSP_OFFSET
i386_target_description
const struct target_desc * i386_target_description(uint64_t xcr0)
Definition: i386-tdep.c:8714