1 /* Native-dependent code for GNU/Linux x86-64.
3 Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010,
4 2011 Free Software Foundation, Inc.
5 Contributed by Jiri Smid, SuSE Labs.
7 This file is part of GDB.
9 This program is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 3 of the License, or
12 (at your option) any later version.
14 This program is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with this program. If not, see <http://www.gnu.org/licenses/>. */
27 #include "linux-nat.h"
28 #include "amd64-linux-tdep.h"
30 #include "gdb_assert.h"
31 #include "gdb_string.h"
32 #include "elf/common.h"
34 #include <sys/ptrace.h>
35 #include <sys/debugreg.h>
36 #include <sys/syscall.h>
37 #include <sys/procfs.h>
38 #include <asm/prctl.h>
39 /* FIXME ezannoni-2003-07-09: we need <sys/reg.h> to be included after
40 <asm/ptrace.h> because the latter redefines FS and GS for no apparent
41 reason, and those definitions don't match the ones that libpthread_db
42 uses, which come from <sys/reg.h>. */
43 /* ezannoni-2003-07-09: I think this is fixed. The extraneous defs have
44 been removed from ptrace.h in the kernel. However, better safe than
46 #include <asm/ptrace.h>
48 #include "gdb_proc_service.h"
50 /* Prototypes for supply_gregset etc. */
53 #include "amd64-tdep.h"
54 #include "i386-linux-tdep.h"
55 #include "amd64-nat.h"
57 #include "i386-xstate.h"
59 #ifndef PTRACE_GETREGSET
60 #define PTRACE_GETREGSET 0x4204
63 #ifndef PTRACE_SETREGSET
64 #define PTRACE_SETREGSET 0x4205
67 /* Per-thread arch-specific data we want to keep. */
71 /* Non-zero if our copy differs from what's recorded in the thread. */
72 int debug_registers_changed;
75 /* Does the current host support PTRACE_GETREGSET? */
76 static int have_ptrace_getregset = -1;
78 /* Mapping between the general-purpose registers in GNU/Linux x86-64
79 `struct user' format and GDB's register cache layout for GNU/Linux
82 Note that most GNU/Linux x86-64 registers are 64-bit, while the
83 GNU/Linux i386 registers are all 32-bit, but since we're
84 little-endian we get away with that. */
86 /* From <sys/reg.h> on GNU/Linux i386. */
87 static int amd64_linux_gregset32_reg_offset[] =
89 RAX * 8, RCX * 8, /* %eax, %ecx */
90 RDX * 8, RBX * 8, /* %edx, %ebx */
91 RSP * 8, RBP * 8, /* %esp, %ebp */
92 RSI * 8, RDI * 8, /* %esi, %edi */
93 RIP * 8, EFLAGS * 8, /* %eip, %eflags */
94 CS * 8, SS * 8, /* %cs, %ss */
95 DS * 8, ES * 8, /* %ds, %es */
96 FS * 8, GS * 8, /* %fs, %gs */
97 -1, -1, -1, -1, -1, -1, -1, -1,
98 -1, -1, -1, -1, -1, -1, -1, -1,
99 -1, -1, -1, -1, -1, -1, -1, -1, -1,
100 -1, -1, -1, -1, -1, -1, -1, -1,
101 ORIG_RAX * 8 /* "orig_eax" */
105 /* Transfering the general-purpose registers between GDB, inferiors
108 /* Fill GDB's register cache with the general-purpose register values
112 supply_gregset (struct regcache *regcache, const elf_gregset_t *gregsetp)
114 amd64_supply_native_gregset (regcache, gregsetp, -1);
117 /* Fill register REGNUM (if it is a general-purpose register) in
118 *GREGSETP with the value in GDB's register cache. If REGNUM is -1,
119 do this for all registers. */
122 fill_gregset (const struct regcache *regcache,
123 elf_gregset_t *gregsetp, int regnum)
125 amd64_collect_native_gregset (regcache, gregsetp, regnum);
128 /* Transfering floating-point registers between GDB, inferiors and cores. */
130 /* Fill GDB's register cache with the floating-point and SSE register
131 values in *FPREGSETP. */
134 supply_fpregset (struct regcache *regcache, const elf_fpregset_t *fpregsetp)
136 amd64_supply_fxsave (regcache, -1, fpregsetp);
139 /* Fill register REGNUM (if it is a floating-point or SSE register) in
140 *FPREGSETP with the value in GDB's register cache. If REGNUM is
141 -1, do this for all registers. */
144 fill_fpregset (const struct regcache *regcache,
145 elf_fpregset_t *fpregsetp, int regnum)
147 amd64_collect_fxsave (regcache, regnum, fpregsetp);
151 /* Transferring arbitrary registers between GDB and inferior. */
153 /* Fetch register REGNUM from the child process. If REGNUM is -1, do
154 this for all registers (including the floating point and SSE
158 amd64_linux_fetch_inferior_registers (struct target_ops *ops,
159 struct regcache *regcache, int regnum)
161 struct gdbarch *gdbarch = get_regcache_arch (regcache);
164 /* GNU/Linux LWP ID's are process ID's. */
165 tid = TIDGET (inferior_ptid);
167 tid = PIDGET (inferior_ptid); /* Not a threaded program. */
169 if (regnum == -1 || amd64_native_gregset_supplies_p (gdbarch, regnum))
173 if (ptrace (PTRACE_GETREGS, tid, 0, (long) ®s) < 0)
174 perror_with_name (_("Couldn't get registers"));
176 amd64_supply_native_gregset (regcache, ®s, -1);
181 if (regnum == -1 || !amd64_native_gregset_supplies_p (gdbarch, regnum))
183 elf_fpregset_t fpregs;
185 if (have_ptrace_getregset)
187 char xstateregs[I386_XSTATE_MAX_SIZE];
190 iov.iov_base = xstateregs;
191 iov.iov_len = sizeof (xstateregs);
192 if (ptrace (PTRACE_GETREGSET, tid,
193 (unsigned int) NT_X86_XSTATE, (long) &iov) < 0)
194 perror_with_name (_("Couldn't get extended state status"));
196 amd64_supply_xsave (regcache, -1, xstateregs);
200 if (ptrace (PTRACE_GETFPREGS, tid, 0, (long) &fpregs) < 0)
201 perror_with_name (_("Couldn't get floating point status"));
203 amd64_supply_fxsave (regcache, -1, &fpregs);
208 /* Store register REGNUM back into the child process. If REGNUM is
209 -1, do this for all registers (including the floating-point and SSE
213 amd64_linux_store_inferior_registers (struct target_ops *ops,
214 struct regcache *regcache, int regnum)
216 struct gdbarch *gdbarch = get_regcache_arch (regcache);
219 /* GNU/Linux LWP ID's are process ID's. */
220 tid = TIDGET (inferior_ptid);
222 tid = PIDGET (inferior_ptid); /* Not a threaded program. */
224 if (regnum == -1 || amd64_native_gregset_supplies_p (gdbarch, regnum))
228 if (ptrace (PTRACE_GETREGS, tid, 0, (long) ®s) < 0)
229 perror_with_name (_("Couldn't get registers"));
231 amd64_collect_native_gregset (regcache, ®s, regnum);
233 if (ptrace (PTRACE_SETREGS, tid, 0, (long) ®s) < 0)
234 perror_with_name (_("Couldn't write registers"));
240 if (regnum == -1 || !amd64_native_gregset_supplies_p (gdbarch, regnum))
242 elf_fpregset_t fpregs;
244 if (have_ptrace_getregset)
246 char xstateregs[I386_XSTATE_MAX_SIZE];
249 iov.iov_base = xstateregs;
250 iov.iov_len = sizeof (xstateregs);
251 if (ptrace (PTRACE_GETREGSET, tid,
252 (unsigned int) NT_X86_XSTATE, (long) &iov) < 0)
253 perror_with_name (_("Couldn't get extended state status"));
255 amd64_collect_xsave (regcache, regnum, xstateregs, 0);
257 if (ptrace (PTRACE_SETREGSET, tid,
258 (unsigned int) NT_X86_XSTATE, (long) &iov) < 0)
259 perror_with_name (_("Couldn't write extended state status"));
263 if (ptrace (PTRACE_GETFPREGS, tid, 0, (long) &fpregs) < 0)
264 perror_with_name (_("Couldn't get floating point status"));
266 amd64_collect_fxsave (regcache, regnum, &fpregs);
268 if (ptrace (PTRACE_SETFPREGS, tid, 0, (long) &fpregs) < 0)
269 perror_with_name (_("Couldn't write floating point status"));
274 /* Support for debug registers. */
277 amd64_linux_dr_get (ptid_t ptid, int regnum)
287 value = ptrace (PTRACE_PEEKUSER, tid,
288 offsetof (struct user, u_debugreg[regnum]), 0);
290 perror_with_name (_("Couldn't read debug register"));
295 /* Set debug register REGNUM to VALUE in only the one LWP of PTID. */
298 amd64_linux_dr_set (ptid_t ptid, int regnum, unsigned long value)
307 ptrace (PTRACE_POKEUSER, tid,
308 offsetof (struct user, u_debugreg[regnum]), value);
310 perror_with_name (_("Couldn't write debug register"));
313 /* Return the inferior's debug register REGNUM. */
316 amd64_linux_dr_get_addr (int regnum)
318 /* DR6 and DR7 are retrieved with some other way. */
319 gdb_assert (DR_FIRSTADDR <= regnum && regnum <= DR_LASTADDR);
321 return amd64_linux_dr_get (inferior_ptid, regnum);
324 /* Return the inferior's DR7 debug control register. */
327 amd64_linux_dr_get_control (void)
329 return amd64_linux_dr_get (inferior_ptid, DR_CONTROL);
332 /* Get DR_STATUS from only the one LWP of INFERIOR_PTID. */
335 amd64_linux_dr_get_status (void)
337 return amd64_linux_dr_get (inferior_ptid, DR_STATUS);
340 /* Callback for iterate_over_lwps. Update the debug registers of
344 update_debug_registers_callback (struct lwp_info *lwp, void *arg)
346 if (lwp->arch_private == NULL)
347 lwp->arch_private = XCNEW (struct arch_lwp_info);
349 /* The actual update is done later just before resuming the lwp, we
350 just mark that the registers need updating. */
351 lwp->arch_private->debug_registers_changed = 1;
353 /* If the lwp isn't stopped, force it to momentarily pause, so we
354 can update its debug registers. */
356 linux_stop_lwp (lwp);
361 /* Set DR_CONTROL to CONTROL in all LWPs of the current inferior. */
364 amd64_linux_dr_set_control (unsigned long control)
366 ptid_t pid_ptid = pid_to_ptid (ptid_get_pid (inferior_ptid));
368 iterate_over_lwps (pid_ptid, update_debug_registers_callback, NULL);
371 /* Set address REGNUM (zero based) to ADDR in all LWPs of the current
375 amd64_linux_dr_set_addr (int regnum, CORE_ADDR addr)
377 ptid_t pid_ptid = pid_to_ptid (ptid_get_pid (inferior_ptid));
379 gdb_assert (regnum >= 0 && regnum <= DR_LASTADDR - DR_FIRSTADDR);
381 iterate_over_lwps (pid_ptid, update_debug_registers_callback, NULL);
384 /* Called when resuming a thread.
385 If the debug regs have changed, update the thread's copies. */
388 amd64_linux_prepare_to_resume (struct lwp_info *lwp)
390 int clear_status = 0;
392 /* NULL means this is the main thread still going through the shell,
393 or, no watchpoint has been set yet. In that case, there's
395 if (lwp->arch_private == NULL)
398 if (lwp->arch_private->debug_registers_changed)
400 struct i386_debug_reg_state *state = i386_debug_reg_state ();
403 for (i = DR_FIRSTADDR; i <= DR_LASTADDR; i++)
404 if (state->dr_ref_count[i] > 0)
406 amd64_linux_dr_set (lwp->ptid, i, state->dr_mirror[i]);
408 /* If we're setting a watchpoint, any change the inferior
409 had done itself to the debug registers needs to be
410 discarded, otherwise, i386_stopped_data_address can get
415 amd64_linux_dr_set (lwp->ptid, DR_CONTROL, state->dr_control_mirror);
417 lwp->arch_private->debug_registers_changed = 0;
420 if (clear_status || lwp->stopped_by_watchpoint)
421 amd64_linux_dr_set (lwp->ptid, DR_STATUS, 0);
425 amd64_linux_new_thread (struct lwp_info *lp)
427 struct arch_lwp_info *info = XCNEW (struct arch_lwp_info);
429 info->debug_registers_changed = 1;
431 lp->arch_private = info;
435 /* This function is called by libthread_db as part of its handling of
436 a request for a thread's local storage address. */
439 ps_get_thread_area (const struct ps_prochandle *ph,
440 lwpid_t lwpid, int idx, void **base)
442 if (gdbarch_ptr_bit (target_gdbarch) == 32)
444 /* The full structure is found in <asm-i386/ldt.h>. The second
445 integer is the LDT's base_address and that is used to locate
446 the thread's local storage. See i386-linux-nat.c more
448 unsigned int desc[4];
450 /* This code assumes that "int" is 32 bits and that
451 GET_THREAD_AREA returns no more than 4 int values. */
452 gdb_assert (sizeof (int) == 4);
453 #ifndef PTRACE_GET_THREAD_AREA
454 #define PTRACE_GET_THREAD_AREA 25
456 if (ptrace (PTRACE_GET_THREAD_AREA,
457 lwpid, (void *) (long) idx, (unsigned long) &desc) < 0)
460 /* Extend the value to 64 bits. Here it's assumed that a "long"
461 and a "void *" are the same. */
462 (*base) = (void *) (long) desc[1];
467 /* This definition comes from prctl.h, but some kernels may not
469 #ifndef PTRACE_ARCH_PRCTL
470 #define PTRACE_ARCH_PRCTL 30
472 /* FIXME: ezannoni-2003-07-09 see comment above about include
473 file order. We could be getting bogus values for these two. */
474 gdb_assert (FS < ELF_NGREG);
475 gdb_assert (GS < ELF_NGREG);
479 if (ptrace (PTRACE_ARCH_PRCTL, lwpid, base, ARCH_GET_FS) == 0)
483 if (ptrace (PTRACE_ARCH_PRCTL, lwpid, base, ARCH_GET_GS) == 0)
486 default: /* Should not happen. */
490 return PS_ERR; /* ptrace failed. */
494 static void (*super_post_startup_inferior) (ptid_t ptid);
497 amd64_linux_child_post_startup_inferior (ptid_t ptid)
499 i386_cleanup_dregs ();
500 super_post_startup_inferior (ptid);
504 /* When GDB is built as a 64-bit application on linux, the
505 PTRACE_GETSIGINFO data is always presented in 64-bit layout. Since
506 debugging a 32-bit inferior with a 64-bit GDB should look the same
507 as debugging it with a 32-bit GDB, we do the 32-bit <-> 64-bit
508 conversion in-place ourselves. */
510 /* These types below (compat_*) define a siginfo type that is layout
511 compatible with the siginfo type exported by the 32-bit userspace
514 typedef int compat_int_t;
515 typedef unsigned int compat_uptr_t;
517 typedef int compat_time_t;
518 typedef int compat_timer_t;
519 typedef int compat_clock_t;
521 struct compat_timeval
523 compat_time_t tv_sec;
527 typedef union compat_sigval
529 compat_int_t sival_int;
530 compat_uptr_t sival_ptr;
533 typedef struct compat_siginfo
541 int _pad[((128 / sizeof (int)) - 3)];
550 /* POSIX.1b timers */
555 compat_sigval_t _sigval;
558 /* POSIX.1b signals */
563 compat_sigval_t _sigval;
572 compat_clock_t _utime;
573 compat_clock_t _stime;
576 /* SIGILL, SIGFPE, SIGSEGV, SIGBUS */
591 #define cpt_si_pid _sifields._kill._pid
592 #define cpt_si_uid _sifields._kill._uid
593 #define cpt_si_timerid _sifields._timer._tid
594 #define cpt_si_overrun _sifields._timer._overrun
595 #define cpt_si_status _sifields._sigchld._status
596 #define cpt_si_utime _sifields._sigchld._utime
597 #define cpt_si_stime _sifields._sigchld._stime
598 #define cpt_si_ptr _sifields._rt._sigval.sival_ptr
599 #define cpt_si_addr _sifields._sigfault._addr
600 #define cpt_si_band _sifields._sigpoll._band
601 #define cpt_si_fd _sifields._sigpoll._fd
603 /* glibc at least up to 2.3.2 doesn't have si_timerid, si_overrun.
604 In their place is si_timer1,si_timer2. */
606 #define si_timerid si_timer1
609 #define si_overrun si_timer2
613 compat_siginfo_from_siginfo (compat_siginfo_t *to, siginfo_t *from)
615 memset (to, 0, sizeof (*to));
617 to->si_signo = from->si_signo;
618 to->si_errno = from->si_errno;
619 to->si_code = from->si_code;
621 if (to->si_code == SI_TIMER)
623 to->cpt_si_timerid = from->si_timerid;
624 to->cpt_si_overrun = from->si_overrun;
625 to->cpt_si_ptr = (intptr_t) from->si_ptr;
627 else if (to->si_code == SI_USER)
629 to->cpt_si_pid = from->si_pid;
630 to->cpt_si_uid = from->si_uid;
632 else if (to->si_code < 0)
634 to->cpt_si_pid = from->si_pid;
635 to->cpt_si_uid = from->si_uid;
636 to->cpt_si_ptr = (intptr_t) from->si_ptr;
640 switch (to->si_signo)
643 to->cpt_si_pid = from->si_pid;
644 to->cpt_si_uid = from->si_uid;
645 to->cpt_si_status = from->si_status;
646 to->cpt_si_utime = from->si_utime;
647 to->cpt_si_stime = from->si_stime;
653 to->cpt_si_addr = (intptr_t) from->si_addr;
656 to->cpt_si_band = from->si_band;
657 to->cpt_si_fd = from->si_fd;
660 to->cpt_si_pid = from->si_pid;
661 to->cpt_si_uid = from->si_uid;
662 to->cpt_si_ptr = (intptr_t) from->si_ptr;
669 siginfo_from_compat_siginfo (siginfo_t *to, compat_siginfo_t *from)
671 memset (to, 0, sizeof (*to));
673 to->si_signo = from->si_signo;
674 to->si_errno = from->si_errno;
675 to->si_code = from->si_code;
677 if (to->si_code == SI_TIMER)
679 to->si_timerid = from->cpt_si_timerid;
680 to->si_overrun = from->cpt_si_overrun;
681 to->si_ptr = (void *) (intptr_t) from->cpt_si_ptr;
683 else if (to->si_code == SI_USER)
685 to->si_pid = from->cpt_si_pid;
686 to->si_uid = from->cpt_si_uid;
690 to->si_pid = from->cpt_si_pid;
691 to->si_uid = from->cpt_si_uid;
692 to->si_ptr = (void *) (intptr_t) from->cpt_si_ptr;
696 switch (to->si_signo)
699 to->si_pid = from->cpt_si_pid;
700 to->si_uid = from->cpt_si_uid;
701 to->si_status = from->cpt_si_status;
702 to->si_utime = from->cpt_si_utime;
703 to->si_stime = from->cpt_si_stime;
709 to->si_addr = (void *) (intptr_t) from->cpt_si_addr;
712 to->si_band = from->cpt_si_band;
713 to->si_fd = from->cpt_si_fd;
716 to->si_pid = from->cpt_si_pid;
717 to->si_uid = from->cpt_si_uid;
718 to->si_ptr = (void* ) (intptr_t) from->cpt_si_ptr;
724 /* Convert a native/host siginfo object, into/from the siginfo in the
725 layout of the inferiors' architecture. Returns true if any
726 conversion was done; false otherwise. If DIRECTION is 1, then copy
727 from INF to NATIVE. If DIRECTION is 0, copy from NATIVE to
731 amd64_linux_siginfo_fixup (struct siginfo *native, gdb_byte *inf, int direction)
733 /* Is the inferior 32-bit? If so, then do fixup the siginfo
735 if (gdbarch_addr_bit (get_frame_arch (get_current_frame ())) == 32)
737 gdb_assert (sizeof (struct siginfo) == sizeof (compat_siginfo_t));
740 compat_siginfo_from_siginfo ((struct compat_siginfo *) inf, native);
742 siginfo_from_compat_siginfo (native, (struct compat_siginfo *) inf);
750 /* Get Linux/x86 target description from running target.
752 Value of CS segment register:
753 1. 64bit process: 0x33.
754 2. 32bit process: 0x23.
757 #define AMD64_LINUX_USER64_CS 0x33
759 static const struct target_desc *
760 amd64_linux_read_description (struct target_ops *ops)
765 static uint64_t xcr0;
767 /* GNU/Linux LWP ID's are process ID's. */
768 tid = TIDGET (inferior_ptid);
770 tid = PIDGET (inferior_ptid); /* Not a threaded program. */
772 /* Get CS register. */
774 cs = ptrace (PTRACE_PEEKUSER, tid,
775 offsetof (struct user_regs_struct, cs), 0);
777 perror_with_name (_("Couldn't get CS register"));
779 is_64bit = cs == AMD64_LINUX_USER64_CS;
781 if (have_ptrace_getregset == -1)
783 uint64_t xstateregs[(I386_XSTATE_SSE_SIZE / sizeof (uint64_t))];
786 iov.iov_base = xstateregs;
787 iov.iov_len = sizeof (xstateregs);
789 /* Check if PTRACE_GETREGSET works. */
790 if (ptrace (PTRACE_GETREGSET, tid,
791 (unsigned int) NT_X86_XSTATE, (long) &iov) < 0)
792 have_ptrace_getregset = 0;
795 have_ptrace_getregset = 1;
797 /* Get XCR0 from XSAVE extended state. */
798 xcr0 = xstateregs[(I386_LINUX_XSAVE_XCR0_OFFSET
799 / sizeof (uint64_t))];
803 /* Check the native XCR0 only if PTRACE_GETREGSET is available. */
804 if (have_ptrace_getregset
805 && (xcr0 & I386_XSTATE_AVX_MASK) == I386_XSTATE_AVX_MASK)
808 return tdesc_amd64_avx_linux;
810 return tdesc_i386_avx_linux;
815 return tdesc_amd64_linux;
817 return tdesc_i386_linux;
821 /* Provide a prototype to silence -Wmissing-prototypes. */
822 void _initialize_amd64_linux_nat (void);
825 _initialize_amd64_linux_nat (void)
827 struct target_ops *t;
829 amd64_native_gregset32_reg_offset = amd64_linux_gregset32_reg_offset;
830 amd64_native_gregset32_num_regs = I386_LINUX_NUM_REGS;
831 amd64_native_gregset64_reg_offset = amd64_linux_gregset_reg_offset;
832 amd64_native_gregset64_num_regs = AMD64_LINUX_NUM_REGS;
834 gdb_assert (ARRAY_SIZE (amd64_linux_gregset32_reg_offset)
835 == amd64_native_gregset32_num_regs);
837 /* Fill in the generic GNU/Linux methods. */
840 i386_use_watchpoints (t);
842 i386_dr_low.set_control = amd64_linux_dr_set_control;
843 i386_dr_low.set_addr = amd64_linux_dr_set_addr;
844 i386_dr_low.get_addr = amd64_linux_dr_get_addr;
845 i386_dr_low.get_status = amd64_linux_dr_get_status;
846 i386_dr_low.get_control = amd64_linux_dr_get_control;
847 i386_set_debug_register_length (8);
849 /* Override the GNU/Linux inferior startup hook. */
850 super_post_startup_inferior = t->to_post_startup_inferior;
851 t->to_post_startup_inferior = amd64_linux_child_post_startup_inferior;
853 /* Add our register access methods. */
854 t->to_fetch_registers = amd64_linux_fetch_inferior_registers;
855 t->to_store_registers = amd64_linux_store_inferior_registers;
857 t->to_read_description = amd64_linux_read_description;
859 /* Register the target. */
860 linux_nat_add_target (t);
861 linux_nat_set_new_thread (t, amd64_linux_new_thread);
862 linux_nat_set_siginfo_fixup (t, amd64_linux_siginfo_fixup);
863 linux_nat_set_prepare_to_resume (t, amd64_linux_prepare_to_resume);