cf424aef0a
- Use signal frame sniffers that look for the signal trampoline instruction sequence to detect most signal frames. - FreeBSD kernels between 9.2 and 10.1 inclusive do not include the signal trampoline code in process core dumps. To detect signal frames for core dumps under these kernels, use the kern.proc.sigtramp.<pid> sysctl to fetch the location of the signal trampoline in the gdb process and assume that PC values within this location are signal frames. This depends on that location being identical for all binaries. gdb/ChangeLog: 2015-02-25 John Baldwin <jhb@FreeBSD.org> * amd64fbsd-nat.c: Include sys/user.h. (_initialize_amd64fbsd_nat): Use the KERN_PROC_SIGTRAMP sysctl instead of KERN_PS_STRINGS to locate the signal trampoline. * i386fbsd-nat.c: Include sys/user.h. (_initialize_i386fbsd_nat): Use the KERN_PROC_SIGTRAMP sysctl instead of KERN_PS_STRINGS to locate the signal trampoline. * amd64fbsd-tdep.c (amd64fbsd_sigtramp_code): New. (amd64fbsd_sigtramp_p): New. (amd64fbsd_sigtramp_start_addr, amd64fbsd_sigtramp_end_addr): No longer set default values. (amd64fbsd_init_abi): Set "sigtramp_p" to "amd64fbsd_sigtramp_p". * i386fbsd-tdep.c (i386fbsd_sigtramp_start) (i386fbsd_sigtramp_middle, i386fbsd_sigtramp_end) (i386fbsd_freebsd4_sigtramp_start) (i386fbsd_freebsd4_sigtramp_middle) (i386fbsd_freebsd4_sigtramp_end, i386fbsd_osigtramp_start) (i386fbsd_osigtramp_middle, i386fbsd_osigtramp_end): New. (i386fbsd_sigtramp_p): New. (i386fbsd_sigtramp_start_addr, i386fbsd_sigtramp_end_addr): No longer set default values. (i386fbsd_init_abi): Set "sigtramp_p" to "i386fbsd_sigtramp_p".
254 lines
6.5 KiB
C
254 lines
6.5 KiB
C
/* Target-dependent code for FreeBSD/amd64.
|
||
|
||
Copyright (C) 2003-2015 Free Software Foundation, Inc.
|
||
|
||
This file is part of GDB.
|
||
|
||
This program is free software; you can redistribute it and/or modify
|
||
it under the terms of the GNU General Public License as published by
|
||
the Free Software Foundation; either version 3 of the License, or
|
||
(at your option) any later version.
|
||
|
||
This program is distributed in the hope that it will be useful,
|
||
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||
GNU General Public License for more details.
|
||
|
||
You should have received a copy of the GNU General Public License
|
||
along with this program. If not, see <http://www.gnu.org/licenses/>. */
|
||
|
||
#include "defs.h"
|
||
#include "arch-utils.h"
|
||
#include "frame.h"
|
||
#include "gdbcore.h"
|
||
#include "regcache.h"
|
||
#include "osabi.h"
|
||
|
||
#include "amd64-tdep.h"
|
||
#include "bsd-uthread.h"
|
||
#include "fbsd-tdep.h"
|
||
#include "solib-svr4.h"
|
||
|
||
/* Support for signal handlers. */
|
||
|
||
/* Return whether THIS_FRAME corresponds to a FreeBSD sigtramp
|
||
routine. */
|
||
|
||
static const gdb_byte amd64fbsd_sigtramp_code[] =
|
||
{
|
||
0x48, 0x8d, 0x7c, 0x24, 0x10, /* lea SIGF_UC(%rsp),%rdi */
|
||
0x6a, 0x00, /* pushq $0 */
|
||
0x48, 0xc7, 0xc0, 0xa1, 0x01, 0x00, 0x00,
|
||
/* movq $SYS_sigreturn,%rax */
|
||
0x0f, 0x05 /* syscall */
|
||
};
|
||
|
||
static int
|
||
amd64fbsd_sigtramp_p (struct frame_info *this_frame)
|
||
{
|
||
CORE_ADDR pc = get_frame_pc (this_frame);
|
||
gdb_byte buf[sizeof amd64fbsd_sigtramp_code];
|
||
|
||
if (!safe_frame_unwind_memory (this_frame, pc, buf, sizeof buf))
|
||
return 0;
|
||
if (memcmp (buf, amd64fbsd_sigtramp_code, sizeof amd64fbsd_sigtramp_code) !=
|
||
0)
|
||
return 0;
|
||
|
||
return 1;
|
||
}
|
||
|
||
/* Assuming THIS_FRAME is for a BSD sigtramp routine, return the
|
||
address of the associated sigcontext structure. */
|
||
|
||
static CORE_ADDR
|
||
amd64fbsd_sigcontext_addr (struct frame_info *this_frame)
|
||
{
|
||
struct gdbarch *gdbarch = get_frame_arch (this_frame);
|
||
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
|
||
CORE_ADDR sp;
|
||
gdb_byte buf[8];
|
||
|
||
/* The `struct sigcontext' (which really is an `ucontext_t' on
|
||
FreeBSD/amd64) lives at a fixed offset in the signal frame. See
|
||
<machine/sigframe.h>. */
|
||
get_frame_register (this_frame, AMD64_RSP_REGNUM, buf);
|
||
sp = extract_unsigned_integer (buf, 8, byte_order);
|
||
return sp + 16;
|
||
}
|
||
|
||
/* FreeBSD 5.1-RELEASE or later. */
|
||
|
||
/* Mapping between the general-purpose registers in `struct reg'
|
||
format and GDB's register cache layout.
|
||
|
||
Note that some registers are 32-bit, but since we're little-endian
|
||
we get away with that. */
|
||
|
||
/* From <machine/reg.h>. */
|
||
static int amd64fbsd_r_reg_offset[] =
|
||
{
|
||
14 * 8, /* %rax */
|
||
11 * 8, /* %rbx */
|
||
13 * 8, /* %rcx */
|
||
12 * 8, /* %rdx */
|
||
9 * 8, /* %rsi */
|
||
8 * 8, /* %rdi */
|
||
10 * 8, /* %rbp */
|
||
20 * 8, /* %rsp */
|
||
7 * 8, /* %r8 ... */
|
||
6 * 8,
|
||
5 * 8,
|
||
4 * 8,
|
||
3 * 8,
|
||
2 * 8,
|
||
1 * 8,
|
||
0 * 8, /* ... %r15 */
|
||
17 * 8, /* %rip */
|
||
19 * 8, /* %eflags */
|
||
18 * 8, /* %cs */
|
||
21 * 8, /* %ss */
|
||
-1, /* %ds */
|
||
-1, /* %es */
|
||
-1, /* %fs */
|
||
-1 /* %gs */
|
||
};
|
||
|
||
/* Location of the signal trampoline. */
|
||
CORE_ADDR amd64fbsd_sigtramp_start_addr;
|
||
CORE_ADDR amd64fbsd_sigtramp_end_addr;
|
||
|
||
/* From <machine/signal.h>. */
|
||
int amd64fbsd_sc_reg_offset[] =
|
||
{
|
||
24 + 6 * 8, /* %rax */
|
||
24 + 7 * 8, /* %rbx */
|
||
24 + 3 * 8, /* %rcx */
|
||
24 + 2 * 8, /* %rdx */
|
||
24 + 1 * 8, /* %rsi */
|
||
24 + 0 * 8, /* %rdi */
|
||
24 + 8 * 8, /* %rbp */
|
||
24 + 22 * 8, /* %rsp */
|
||
24 + 4 * 8, /* %r8 ... */
|
||
24 + 5 * 8,
|
||
24 + 9 * 8,
|
||
24 + 10 * 8,
|
||
24 + 11 * 8,
|
||
24 + 12 * 8,
|
||
24 + 13 * 8,
|
||
24 + 14 * 8, /* ... %r15 */
|
||
24 + 19 * 8, /* %rip */
|
||
24 + 21 * 8, /* %eflags */
|
||
24 + 20 * 8, /* %cs */
|
||
24 + 23 * 8, /* %ss */
|
||
-1, /* %ds */
|
||
-1, /* %es */
|
||
-1, /* %fs */
|
||
-1 /* %gs */
|
||
};
|
||
|
||
/* From /usr/src/lib/libc/amd64/gen/_setjmp.S. */
|
||
static int amd64fbsd_jmp_buf_reg_offset[] =
|
||
{
|
||
-1, /* %rax */
|
||
1 * 8, /* %rbx */
|
||
-1, /* %rcx */
|
||
-1, /* %rdx */
|
||
-1, /* %rsi */
|
||
-1, /* %rdi */
|
||
3 * 8, /* %rbp */
|
||
2 * 8, /* %rsp */
|
||
-1, /* %r8 ... */
|
||
-1,
|
||
-1,
|
||
-1, /* ... %r11 */
|
||
4 * 8, /* %r12 ... */
|
||
5 * 8,
|
||
6 * 8,
|
||
7 * 8, /* ... %r15 */
|
||
0 * 8 /* %rip */
|
||
};
|
||
|
||
static void
|
||
amd64fbsd_supply_uthread (struct regcache *regcache,
|
||
int regnum, CORE_ADDR addr)
|
||
{
|
||
gdb_byte buf[8];
|
||
int i;
|
||
|
||
gdb_assert (regnum >= -1);
|
||
|
||
for (i = 0; i < ARRAY_SIZE (amd64fbsd_jmp_buf_reg_offset); i++)
|
||
{
|
||
if (amd64fbsd_jmp_buf_reg_offset[i] != -1
|
||
&& (regnum == -1 || regnum == i))
|
||
{
|
||
read_memory (addr + amd64fbsd_jmp_buf_reg_offset[i], buf, 8);
|
||
regcache_raw_supply (regcache, i, buf);
|
||
}
|
||
}
|
||
}
|
||
|
||
static void
|
||
amd64fbsd_collect_uthread (const struct regcache *regcache,
|
||
int regnum, CORE_ADDR addr)
|
||
{
|
||
gdb_byte buf[8];
|
||
int i;
|
||
|
||
gdb_assert (regnum >= -1);
|
||
|
||
for (i = 0; i < ARRAY_SIZE (amd64fbsd_jmp_buf_reg_offset); i++)
|
||
{
|
||
if (amd64fbsd_jmp_buf_reg_offset[i] != -1
|
||
&& (regnum == -1 || regnum == i))
|
||
{
|
||
regcache_raw_collect (regcache, i, buf);
|
||
write_memory (addr + amd64fbsd_jmp_buf_reg_offset[i], buf, 8);
|
||
}
|
||
}
|
||
}
|
||
|
||
static void
|
||
amd64fbsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
|
||
{
|
||
struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
|
||
|
||
/* Generic FreeBSD support. */
|
||
fbsd_init_abi (info, gdbarch);
|
||
|
||
/* Obviously FreeBSD is BSD-based. */
|
||
i386bsd_init_abi (info, gdbarch);
|
||
|
||
tdep->gregset_reg_offset = amd64fbsd_r_reg_offset;
|
||
tdep->gregset_num_regs = ARRAY_SIZE (amd64fbsd_r_reg_offset);
|
||
tdep->sizeof_gregset = 22 * 8;
|
||
|
||
amd64_init_abi (info, gdbarch);
|
||
|
||
tdep->sigtramp_p = amd64fbsd_sigtramp_p;
|
||
tdep->sigtramp_start = amd64fbsd_sigtramp_start_addr;
|
||
tdep->sigtramp_end = amd64fbsd_sigtramp_end_addr;
|
||
tdep->sigcontext_addr = amd64fbsd_sigcontext_addr;
|
||
tdep->sc_reg_offset = amd64fbsd_sc_reg_offset;
|
||
tdep->sc_num_regs = ARRAY_SIZE (amd64fbsd_sc_reg_offset);
|
||
|
||
/* FreeBSD provides a user-level threads implementation. */
|
||
bsd_uthread_set_supply_uthread (gdbarch, amd64fbsd_supply_uthread);
|
||
bsd_uthread_set_collect_uthread (gdbarch, amd64fbsd_collect_uthread);
|
||
|
||
/* FreeBSD uses SVR4-style shared libraries. */
|
||
set_solib_svr4_fetch_link_map_offsets
|
||
(gdbarch, svr4_lp64_fetch_link_map_offsets);
|
||
}
|
||
|
||
|
||
/* Provide a prototype to silence -Wmissing-prototypes. */
|
||
void _initialize_amd64fbsd_tdep (void);
|
||
|
||
void
|
||
_initialize_amd64fbsd_tdep (void)
|
||
{
|
||
gdbarch_register_osabi (bfd_arch_i386, bfd_mach_x86_64,
|
||
GDB_OSABI_FREEBSD_ELF, amd64fbsd_init_abi);
|
||
}
|