| 1 | /* Native-dependent code for FreeBSD/amd64. |
| 2 | |
| 3 | Copyright (C) 2003-2015 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 "amd64bsd-nat.h" |
| 36 | #include "x86-nat.h" |
| 37 | \f |
| 38 | |
| 39 | /* Offset in `struct reg' where MEMBER is stored. */ |
| 40 | #define REG_OFFSET(member) offsetof (struct reg, member) |
| 41 | |
| 42 | /* At amd64fbsd64_r_reg_offset[REGNUM] you'll find the offset in |
| 43 | `struct reg' location where the GDB register REGNUM is stored. |
| 44 | Unsupported registers are marked with `-1'. */ |
| 45 | static int amd64fbsd64_r_reg_offset[] = |
| 46 | { |
| 47 | REG_OFFSET (r_rax), |
| 48 | REG_OFFSET (r_rbx), |
| 49 | REG_OFFSET (r_rcx), |
| 50 | REG_OFFSET (r_rdx), |
| 51 | REG_OFFSET (r_rsi), |
| 52 | REG_OFFSET (r_rdi), |
| 53 | REG_OFFSET (r_rbp), |
| 54 | REG_OFFSET (r_rsp), |
| 55 | REG_OFFSET (r_r8), |
| 56 | REG_OFFSET (r_r9), |
| 57 | REG_OFFSET (r_r10), |
| 58 | REG_OFFSET (r_r11), |
| 59 | REG_OFFSET (r_r12), |
| 60 | REG_OFFSET (r_r13), |
| 61 | REG_OFFSET (r_r14), |
| 62 | REG_OFFSET (r_r15), |
| 63 | REG_OFFSET (r_rip), |
| 64 | REG_OFFSET (r_rflags), |
| 65 | REG_OFFSET (r_cs), |
| 66 | REG_OFFSET (r_ss), |
| 67 | -1, |
| 68 | -1, |
| 69 | -1, |
| 70 | -1 |
| 71 | }; |
| 72 | \f |
| 73 | |
| 74 | /* Mapping between the general-purpose registers in FreeBSD/amd64 |
| 75 | `struct reg' format and GDB's register cache layout for |
| 76 | FreeBSD/i386. |
| 77 | |
| 78 | Note that most FreeBSD/amd64 registers are 64-bit, while the |
| 79 | FreeBSD/i386 registers are all 32-bit, but since we're |
| 80 | little-endian we get away with that. */ |
| 81 | |
| 82 | /* From <machine/reg.h>. */ |
| 83 | static int amd64fbsd32_r_reg_offset[I386_NUM_GREGS] = |
| 84 | { |
| 85 | 14 * 8, 13 * 8, /* %eax, %ecx */ |
| 86 | 12 * 8, 11 * 8, /* %edx, %ebx */ |
| 87 | 20 * 8, 10 * 8, /* %esp, %ebp */ |
| 88 | 9 * 8, 8 * 8, /* %esi, %edi */ |
| 89 | 17 * 8, 19 * 8, /* %eip, %eflags */ |
| 90 | 18 * 8, 21 * 8, /* %cs, %ss */ |
| 91 | -1, -1, -1, -1 /* %ds, %es, %fs, %gs */ |
| 92 | }; |
| 93 | \f |
| 94 | |
| 95 | /* Support for debugging kernel virtual memory images. */ |
| 96 | |
| 97 | #include <machine/pcb.h> |
| 98 | #include <osreldate.h> |
| 99 | |
| 100 | #include "bsd-kvm.h" |
| 101 | |
| 102 | static int |
| 103 | amd64fbsd_supply_pcb (struct regcache *regcache, struct pcb *pcb) |
| 104 | { |
| 105 | /* The following is true for FreeBSD 5.2: |
| 106 | |
| 107 | The pcb contains %rip, %rbx, %rsp, %rbp, %r12, %r13, %r14, %r15, |
| 108 | %ds, %es, %fs and %gs. This accounts for all callee-saved |
| 109 | registers specified by the psABI and then some. Here %esp |
| 110 | contains the stack pointer at the point just after the call to |
| 111 | cpu_switch(). From this information we reconstruct the register |
| 112 | state as it would like when we just returned from cpu_switch(). */ |
| 113 | |
| 114 | /* The stack pointer shouldn't be zero. */ |
| 115 | if (pcb->pcb_rsp == 0) |
| 116 | return 0; |
| 117 | |
| 118 | pcb->pcb_rsp += 8; |
| 119 | regcache_raw_supply (regcache, AMD64_RIP_REGNUM, &pcb->pcb_rip); |
| 120 | regcache_raw_supply (regcache, AMD64_RBX_REGNUM, &pcb->pcb_rbx); |
| 121 | regcache_raw_supply (regcache, AMD64_RSP_REGNUM, &pcb->pcb_rsp); |
| 122 | regcache_raw_supply (regcache, AMD64_RBP_REGNUM, &pcb->pcb_rbp); |
| 123 | regcache_raw_supply (regcache, 12, &pcb->pcb_r12); |
| 124 | regcache_raw_supply (regcache, 13, &pcb->pcb_r13); |
| 125 | regcache_raw_supply (regcache, 14, &pcb->pcb_r14); |
| 126 | regcache_raw_supply (regcache, 15, &pcb->pcb_r15); |
| 127 | #if (__FreeBSD_version < 800075) && (__FreeBSD_kernel_version < 800075) |
| 128 | /* struct pcb provides the pcb_ds/pcb_es/pcb_fs/pcb_gs fields only |
| 129 | up until __FreeBSD_version 800074: The removal of these fields |
| 130 | occurred on 2009-04-01 while the __FreeBSD_version number was |
| 131 | bumped to 800075 on 2009-04-06. So 800075 is the closest version |
| 132 | number where we should not try to access these fields. */ |
| 133 | regcache_raw_supply (regcache, AMD64_DS_REGNUM, &pcb->pcb_ds); |
| 134 | regcache_raw_supply (regcache, AMD64_ES_REGNUM, &pcb->pcb_es); |
| 135 | regcache_raw_supply (regcache, AMD64_FS_REGNUM, &pcb->pcb_fs); |
| 136 | regcache_raw_supply (regcache, AMD64_GS_REGNUM, &pcb->pcb_gs); |
| 137 | #endif |
| 138 | |
| 139 | return 1; |
| 140 | } |
| 141 | \f |
| 142 | |
| 143 | static void (*super_mourn_inferior) (struct target_ops *ops); |
| 144 | |
| 145 | static void |
| 146 | amd64fbsd_mourn_inferior (struct target_ops *ops) |
| 147 | { |
| 148 | #ifdef HAVE_PT_GETDBREGS |
| 149 | x86_cleanup_dregs (); |
| 150 | #endif |
| 151 | super_mourn_inferior (ops); |
| 152 | } |
| 153 | |
| 154 | /* Implement the to_read_description method. */ |
| 155 | |
| 156 | static const struct target_desc * |
| 157 | amd64fbsd_read_description (struct target_ops *ops) |
| 158 | { |
| 159 | #ifdef PT_GETXSTATE_INFO |
| 160 | static int xsave_probed; |
| 161 | static uint64_t xcr0; |
| 162 | #endif |
| 163 | struct reg regs; |
| 164 | int is64; |
| 165 | |
| 166 | if (ptrace (PT_GETREGS, ptid_get_pid (inferior_ptid), |
| 167 | (PTRACE_TYPE_ARG3) ®s, 0) == -1) |
| 168 | perror_with_name (_("Couldn't get registers")); |
| 169 | is64 = (regs.r_cs == GSEL (GUCODE_SEL, SEL_UPL)); |
| 170 | #ifdef PT_GETXSTATE_INFO |
| 171 | if (!xsave_probed) |
| 172 | { |
| 173 | struct ptrace_xstate_info info; |
| 174 | |
| 175 | if (ptrace (PT_GETXSTATE_INFO, ptid_get_pid (inferior_ptid), |
| 176 | (PTRACE_TYPE_ARG3) &info, sizeof (info)) == 0) |
| 177 | { |
| 178 | amd64bsd_xsave_len = info.xsave_len; |
| 179 | xcr0 = info.xsave_mask; |
| 180 | } |
| 181 | xsave_probed = 1; |
| 182 | } |
| 183 | |
| 184 | if (amd64bsd_xsave_len != 0) |
| 185 | { |
| 186 | if (is64) |
| 187 | return amd64_target_description (xcr0); |
| 188 | else |
| 189 | return i386_target_description (xcr0); |
| 190 | } |
| 191 | #endif |
| 192 | if (is64) |
| 193 | return tdesc_amd64; |
| 194 | else |
| 195 | return tdesc_i386; |
| 196 | } |
| 197 | |
| 198 | /* Provide a prototype to silence -Wmissing-prototypes. */ |
| 199 | void _initialize_amd64fbsd_nat (void); |
| 200 | |
| 201 | void |
| 202 | _initialize_amd64fbsd_nat (void) |
| 203 | { |
| 204 | struct target_ops *t; |
| 205 | int offset; |
| 206 | |
| 207 | amd64_native_gregset32_reg_offset = amd64fbsd32_r_reg_offset; |
| 208 | amd64_native_gregset64_reg_offset = amd64fbsd64_r_reg_offset; |
| 209 | |
| 210 | /* Add some extra features to the common *BSD/i386 target. */ |
| 211 | t = amd64bsd_target (); |
| 212 | |
| 213 | #ifdef HAVE_PT_GETDBREGS |
| 214 | |
| 215 | x86_use_watchpoints (t); |
| 216 | |
| 217 | x86_dr_low.set_control = amd64bsd_dr_set_control; |
| 218 | x86_dr_low.set_addr = amd64bsd_dr_set_addr; |
| 219 | x86_dr_low.get_addr = amd64bsd_dr_get_addr; |
| 220 | x86_dr_low.get_status = amd64bsd_dr_get_status; |
| 221 | x86_dr_low.get_control = amd64bsd_dr_get_control; |
| 222 | x86_set_debug_register_length (8); |
| 223 | |
| 224 | #endif /* HAVE_PT_GETDBREGS */ |
| 225 | |
| 226 | super_mourn_inferior = t->to_mourn_inferior; |
| 227 | t->to_mourn_inferior = amd64fbsd_mourn_inferior; |
| 228 | t->to_read_description = amd64fbsd_read_description; |
| 229 | |
| 230 | fbsd_nat_add_target (t); |
| 231 | |
| 232 | /* Support debugging kernel virtual memory images. */ |
| 233 | bsd_kvm_add_target (amd64fbsd_supply_pcb); |
| 234 | |
| 235 | /* To support the recognition of signal handlers, i386bsd-tdep.c |
| 236 | hardcodes some constants. Inclusion of this file means that we |
| 237 | are compiling a native debugger, which means that we can use the |
| 238 | system header files and sysctl(3) to get at the relevant |
| 239 | information. */ |
| 240 | |
| 241 | #define SC_REG_OFFSET amd64fbsd_sc_reg_offset |
| 242 | |
| 243 | /* We only check the program counter, stack pointer and frame |
| 244 | pointer since these members of `struct sigcontext' are essential |
| 245 | for providing backtraces. */ |
| 246 | |
| 247 | #define SC_RIP_OFFSET SC_REG_OFFSET[AMD64_RIP_REGNUM] |
| 248 | #define SC_RSP_OFFSET SC_REG_OFFSET[AMD64_RSP_REGNUM] |
| 249 | #define SC_RBP_OFFSET SC_REG_OFFSET[AMD64_RBP_REGNUM] |
| 250 | |
| 251 | /* Override the default value for the offset of the program counter |
| 252 | in the sigcontext structure. */ |
| 253 | offset = offsetof (struct sigcontext, sc_rip); |
| 254 | |
| 255 | if (SC_RIP_OFFSET != offset) |
| 256 | { |
| 257 | warning (_("\ |
| 258 | offsetof (struct sigcontext, sc_rip) yields %d instead of %d.\n\ |
| 259 | Please report this to <bug-gdb@gnu.org>."), |
| 260 | offset, SC_RIP_OFFSET); |
| 261 | } |
| 262 | |
| 263 | SC_RIP_OFFSET = offset; |
| 264 | |
| 265 | /* Likewise for the stack pointer. */ |
| 266 | offset = offsetof (struct sigcontext, sc_rsp); |
| 267 | |
| 268 | if (SC_RSP_OFFSET != offset) |
| 269 | { |
| 270 | warning (_("\ |
| 271 | offsetof (struct sigcontext, sc_rsp) yields %d instead of %d.\n\ |
| 272 | Please report this to <bug-gdb@gnu.org>."), |
| 273 | offset, SC_RSP_OFFSET); |
| 274 | } |
| 275 | |
| 276 | SC_RSP_OFFSET = offset; |
| 277 | |
| 278 | /* And the frame pointer. */ |
| 279 | offset = offsetof (struct sigcontext, sc_rbp); |
| 280 | |
| 281 | if (SC_RBP_OFFSET != offset) |
| 282 | { |
| 283 | warning (_("\ |
| 284 | offsetof (struct sigcontext, sc_rbp) yields %d instead of %d.\n\ |
| 285 | Please report this to <bug-gdb@gnu.org>."), |
| 286 | offset, SC_RBP_OFFSET); |
| 287 | } |
| 288 | |
| 289 | SC_RBP_OFFSET = offset; |
| 290 | |
| 291 | #ifdef KERN_PROC_SIGTRAMP |
| 292 | /* Normally signal frames are detected via amd64fbsd_sigtramp_p. |
| 293 | However, FreeBSD 9.2 through 10.1 do not include the page holding |
| 294 | the signal code in core dumps. These releases do provide a |
| 295 | kern.proc.sigtramp.<pid> sysctl that returns the location of the |
| 296 | signal trampoline for a running process. We fetch the location |
| 297 | of the current (gdb) process and use this to identify signal |
| 298 | frames in core dumps from these releases. Note that this only |
| 299 | works for core dumps of 64-bit (FreeBSD/amd64) processes and does |
| 300 | not handle core dumps of 32-bit (FreeBSD/i386) processes. */ |
| 301 | { |
| 302 | int mib[4]; |
| 303 | struct kinfo_sigtramp kst; |
| 304 | size_t len; |
| 305 | |
| 306 | mib[0] = CTL_KERN; |
| 307 | mib[1] = KERN_PROC; |
| 308 | mib[2] = KERN_PROC_SIGTRAMP; |
| 309 | mib[3] = getpid (); |
| 310 | len = sizeof (kst); |
| 311 | if (sysctl (mib, 4, &kst, &len, NULL, 0) == 0) |
| 312 | { |
| 313 | amd64fbsd_sigtramp_start_addr = (uintptr_t) kst.ksigtramp_start; |
| 314 | amd64fbsd_sigtramp_end_addr = (uintptr_t) kst.ksigtramp_end; |
| 315 | } |
| 316 | } |
| 317 | #endif |
| 318 | } |