Add the function lwp_is_stepping which indicates whether the given LWP
is currently single-stepping. This is a common interface, usable from
native GDB as well as from gdbserver.
gdb/gdbserver/ChangeLog:
* linux-low.c (lwp_is_stepping): New function.
gdb/ChangeLog:
* nat/linux-nat.h (lwp_is_stepping): New declaration.
* linux-nat.c (lwp_is_stepping): New function.
GLIBC BZ#20311 [1] proc_service.h install patch also remove 'const'
attributes from ps_get_thread_area and comment #15 discuss why to remove
the const attribute (basically since it a callback with the struct
ps_prochandle owned by the client it should be able to modify it if
it the case).
On default build this is not the issue and current g++ does not trigger
any issue with this mismatch declaration. However, on some bootstrap
build configuration where gdbserver is build with gcc instead this
triggers:
error: conflicting types for 'ps_get_thread_area'
This patch fixes it by syncing the declaration with GLIBC.
[1] https://sourceware.org/bugzilla/show_bug.cgi?id=20311
gdb/ChangeLog:
2016-08-25 Adhemerval Zanella <adhemerval.zanella@linaro.org>
* aarch64-linux-nat.c (ps_get_thread_area): Remove const from
struct ps_prochandle.
* amd64-linux-nat.c (ps_get_thread_area): Likewise.
* arm-linux-nat.c (ps_get_thread_area): Likewise.
* gdb_proc_service.h (ps_get_thread_area): Likewise.
* i386-linux-nat.c (ps_get_thread_area): Likewise.
* m68klinux-nat.c (ps_get_thread_area): Likewise.
* mips-linux-nat.c (ps_get_thread_area): Likewise.
* nat/aarch64-linux.c (aarch64_ps_get_thread_area): Likewise.
* nat/aarch64-linux.h (aarch64_ps_get_thread_area): Likewise.
* xtensa-linux-nat.c (ps_get_thread_area): Likewise.
gdb/gdbserver/ChangeLog:
2016-08-25 Adhemerval Zanella <adhemerval.zanella@linaro.org>
PR server/20491
* gdb_proc_service.h (ps_get_thread_area): Remove const from struct
ps_prochandle.
* linux-aarch64-low.c (ps_get_thread_area): Likewise.
* linux-arm-low.c (ps_get_thread_area): Likewise.
* linux-crisv32-low.c (ps_get_thread_area): Likewise.
* linux-m68k-low.c (ps_get_thread_area): Likewise.
* linux-mips-low.c (ps_get_thread_area): Likewise.
* linux-nios2-low.c (ps_get_thread_area): Likewise.
* linux-tic6x-low.c (ps_get_thread_area): Likewise.
* linux-x86-low.c (ps_get_thread_area): Likewise.
* linux-xtensa-low.c (ps_get_thread_area): Likewise.
Fixes, on NIOS GNU/Linux:
In file included from
/scratch/mbilal/nois-lite/src/gdb-trunk/gdb/gdbserver/../nat/linux-ptrace.c:26:0:
/scratch/mbilal/nois-lite/src/gdb-trunk/gdb/gdbserver/../gregset.h:27:23:
error: unknown type name 'gregset_t'
#define GDB_GREGSET_T gregset_t
^
Fix this by including sys/procfs.h directly. We shouldn't really be
including a gdb-only header in a gdb/nat/ file, anyway. Whoops.
gdb/ChangeLog:
2016-08-11 Pedro Alves <palves@redhat.com>
PR gdb/20413
* nat/linux-ptrace.c: Include <sys/procfs.h> instead of
"gregset.h".
An x32 gdb always issues this warning:
(gdb) start
Temporary breakpoint 1 at 0x4043e9: file foo.c, line 25.
Starting program: a.out
warning: linux_ptrace_test_ret_to_nx: Cannot PTRACE_PEEKUSER: Input/output error
Temporary breakpoint 1, main (argc=1, argv=0xffffd544) at foo.c:25
25 {
(gdb)
As described in Linux commit 55283e253771 (x32: Add ptrace for x32):
[...] PTRACE_PEEKUSR and PTRACE_POKEUSR are only allowed to access
segment and debug registers. [...]
The fix is to use PTRACE_GETREGS instead.
gdb/ChangeLog:
2016-07-26 Pedro Alves <palves@redhat.com>
* nat/linux-ptrace.c: Include "gregset.h".
(linux_ptrace_test_ret_to_nx): Use PTRACE_GETREGS instead of
PTRACE_PEEKUSER.
Building an x32 gdb trips on a static assertion:
In file included from .../src/gdb/common/common-defs.h:71:0,
from .../src/gdb/nat/amd64-linux-siginfo.c:21:
.../src/gdb/common/gdb_assert.h:26:66: error: size of array ‘never_defined_just_used_for_checking’ is negative
extern int never_defined_just_used_for_checking[(expr) ? 1 : -1]
^
.../src/gdb/nat/amd64-linux-siginfo.c:113:1: note: in expansion of macro ‘gdb_static_assert’
gdb_static_assert (sizeof (nat_siginfo_t) == sizeof (siginfo_t));
^
The problem is that the way nat_siginfo_t is defined, it can only
match the host's siginfo_t object when gdb is built as a 64-bit
program.
Several bits of nat_siginfo_t are off:
- nat_siginfo_t's _pad field's definition is:
int _pad[((128 / sizeof (int)) - 4)];
while /usr/include/bits/siginfo.h has:
# define __SI_MAX_SIZE 128
# if __WORDSIZE == 64
# define __SI_PAD_SIZE ((__SI_MAX_SIZE / sizeof (int)) - 4)
# else
# define __SI_PAD_SIZE ((__SI_MAX_SIZE / sizeof (int)) - 3)
# endif
and __WORDSIZE == 32 for x32. This is what causes the size of
nat_siginfo_t to be wrong and the assertion to fail.
- the nat_clock_t type is incorrect for 64-bit. We have this:
/* For native 64-bit, clock_t in _sigchld is 64bit aligned at 4 bytes. */
typedef long __attribute__ ((__aligned__ (4))) nat_clock_t;
however, /usr/include/bits/siginfo.h has:
# if defined __x86_64__ && __WORDSIZE == 32
/* si_utime and si_stime must be 4 byte aligned for x32 to match the
kernel. We align siginfo_t to 8 bytes so that si_utime and si_stime
are actually aligned to 8 bytes since their offsets are multiple of
8 bytes. */
typedef __clock_t __attribute__ ((__aligned__ (4))) __sigchld_clock_t;
# define __SI_ALIGNMENT __attribute__ ((__aligned__ (8)))
# else
typedef __clock_t __sigchld_clock_t;
# define __SI_ALIGNMENT
# endif
So we're currently forcing 4-byte alignment on clock_t, when it
should only be so for x32, not 64-bit.
The fix:
- Leaves nat_siginfo_t strictly for the 64-bit ABI.
- Adds a new typedef for the siginfo type that ptrace uses
(ptrace_siginfo_t). An x32 gdb always gets/sets an x32 siginfo_t
type with PTRACE_GETSIGINFO/PTRACE_SETSIGINFO.
- Uses this new ptrace_siginfo_t type instead of nat_siginfo_t as the
intermediate conversion type.
gdb/ChangeLog:
2016-07-26 Pedro Alves <palves@redhat.com>
* amd64-linux-nat.c (amd64_linux_siginfo_fixup): Rename 'native'
parameter to 'ptrace'.
* nat/amd64-linux-siginfo.c (GDB_SI_SIZE): New define.
(nat_uptr_t): New an unsigned long.
(nat_clock_t): Remove attribute __aligned__.
(struct nat_timeval): Delete.
(nat_siginfo_t): Remove attribute __aligned__.
(ptrace_siginfo_t): Define.
(compat_siginfo_from_siginfo, siginfo_from_compat_siginfo)
(compat_x32_siginfo_from_siginfo)
(siginfo_from_compat_x32_siginfo): Make 'from' parameter const.
Convert through a ptrace_siginfo_t instead of a nat_siginfo_t.
Remove casts.
(amd64_linux_siginfo_fixup_common): Rename 'native' parameter to
'ptrace'. Remove static assertions.
(top level): New static assertions.
gdb/gdbserver/ChangeLog:
2016-07-26 Pedro Alves <palves@redhat.com>
* linux-x86-low.c (x86_siginfo_fixup): Rename 'native' parameter
to 'ptrace'.
Since Linux 2.6.33, /proc/PID/status shows "t (tracing stop)", with
lowercase 't'. Because GDB is only expecting "T (tracing stop)", GDB
can incorrectly suppress errors in check_ptrace_stopped_lwp_gone:
1578 if (!check_ptrace_stopped_lwp_gone (lp))
1579 throw_exception (ex);
Ref: https://sourceware.org/ml/gdb-patches/2016-06/msg00072.html
2016-07-25 Pedro Alves <palves@redhat.com>
Jan Kratochvil <jan.kratochvil@redhat.com>
* nat/linux-procfs.c (parse_proc_status_state): Handle lowercase
't'.
Parse the process's /proc/PID/status state into an enum instead of the
current scheme of passing state strings around.
gdb/ChangeLog:
2016-07-25 Pedro Alves <palves@redhat.com>
* nat/linux-procfs.c (enum proc_state): New enum.
(parse_proc_status_state): New function.
(linux_proc_pid_get_state): Replace output string buffer parameter
with an output proc_state parameter. Use parse_proc_status_state.
(linux_proc_pid_is_gone): Adjust to use proc_state values.
(linux_proc_pid_has_state): Change type of 'state' parameter; now
an enum proc_state. Adjust to linux_proc_pid_get_state interface
change.
(linux_proc_pid_is_stopped)
(linux_proc_pid_is_trace_stopped_nowarn)
(linux_proc_pid_is_zombie_maybe_warn): Adjust to
linux_proc_pid_get_state interface change.
The problem here is ARMv8.1 (and ARMv8.2) define a
different debug version than ARMv8 (7 and 8 respectively).
This fixes hw watchpoints and breakpoints by checking
for those debug versions too.
Committed as obvious after a test on aarch64-linux-gnu
(on a ThunderX machine which has ARMv8.1 support enabled).
ChangeLog:
* nat/aarch64-linux-hw-point.c
(aarch64_linux_get_debug_reg_capacity): Handle
ARMv8.1 and ARMv8.2 debug versions.
* nat/aarch64-linux-hw-point.h
(AARCH64_DEBUG_ARCH_V8_1): New define.
(AARCH64_DEBUG_ARCH_V8_2): New define.
Signed-off-by: Andrew Pinski <apinski@cavium.com>
Native GDB looks up the function td_thr_validate from libthread_db.so
on Linux, but the value is never used. This commit removes this dead
code.
gdb/ChangeLog:
* nat/gdb_thread_db.h (td_thr_validate_ftype): Remove typedef.
* linux-thread-db.c (struct thread_db_info) <td_thr_validate_p>:
Remove field.
(try_thread_db_load_1): Remove td_thr_validate initialization.
This makes the MIPS Linux backends recognize TRAP_BRKPT and
TRAP_HWBKPT in siginfo.si_code in addition to SI_KERNEL, since Linux
4.6 now reports the finer-grained si_code values too.
Refs:
https://sourceware.org/ml/gdb-patches/2016-02/msg00756.htmlhttps://sourceware.org/ml/gdb-patches/2016-04/msg00090.html
On kernels that report SI_KERNEL (<= 4.5), we'll enter the "ambiguous"
path of save_stop_reason:
if (GDB_ARCH_IS_TRAP_BRKPT (siginfo.si_code)
&& GDB_ARCH_IS_TRAP_HWBKPT (siginfo.si_code))
{
/* The si_code is ambiguous on this arch -- check debug
registers. */
if (!check_stopped_by_watchpoint (lp))
lp->stop_reason = TARGET_STOPPED_BY_SW_BREAKPOINT;
}
while on kernels that report the finer-grained si_code values (>= 4.6),
we'll enter the corresponding branches:
else if (GDB_ARCH_IS_TRAP_BRKPT (siginfo.si_code))
{
}
else if (GDB_ARCH_IS_TRAP_HWBKPT (siginfo.si_code))
{
...
gdb/ChangeLog:
2016-04-15 Pedro Alves <palves@redhat.com>
* nat/linux-ptrace.h [__mips__] (GDB_ARCH_IS_TRAP_BRKPT): Also
accept TRAP_BRKPT.
[__mips__] (GDB_ARCH_IS_TRAP_HWBKPT): Also accept TRAP_HWBKPT.
This unbreaks pending/delayed breakpoints handling, as well as
hardware watchpoints, on MIPS.
Ref: https://sourceware.org/ml/gdb-patches/2016-02/msg00681.html
The MIPS kernel reports SI_KERNEL for all kernel generated traps,
instead of TRAP_BRKPT / TRAP_HWBKPT, but GDB isn't aware of this.
Basically, this commit:
- Folds watchpoints logic into check_stopped_by_breakpoint, and
renames it to save_stop_reason.
- Adds GDB_ARCH_IS_TRAP_HWBKPT.
- Makes MIPS set both GDB_ARCH_IS_TRAP_BRPT and
GDB_ARCH_IS_TRAP_HWBKPT to SI_KERNEL. In save_stop_reason, we
handle the case of the same si_code returning true for both
TRAP_BRPT and TRAP_HWBKPT by looking at what the debug registers
say.
Tested on x86-64 Fedora 20, native and gdbserver.
gdb/ChangeLog:
2016-02-24 Pedro Alves <palves@redhat.com>
* linux-nat.c (save_sigtrap) Delete.
(stop_wait_callback): Call save_stop_reason instead of
save_sigtrap.
(check_stopped_by_breakpoint): Rename to ...
(save_stop_reason): ... this. Bits of save_sigtrap folded here.
Use GDB_ARCH_IS_TRAP_HWBKPT and handle ambiguous
GDB_ARCH_IS_TRAP_BRKPT / GDB_ARCH_IS_TRAP_HWBKPT. Factor out
common code between the USE_SIGTRAP_SIGINFO and
!USE_SIGTRAP_SIGINFO blocks.
(linux_nat_filter_event): Call save_stop_reason instead of
save_sigtrap.
* nat/linux-ptrace.h: Check for both SI_KERNEL and TRAP_BRKPT
si_code for MIPS.
* nat/linux-ptrace.h: Fix "TRAP_HWBPT" typo in x86 table. Add
comments on MIPS behavior.
(GDB_ARCH_IS_TRAP_HWBKPT): Define for all archs.
gdb/gdbserver/ChangeLog:
2016-02-24 Pedro Alves <palves@redhat.com>
* linux-low.c (check_stopped_by_breakpoint): Rename to ...
(save_stop_reason): ... this. Use GDB_ARCH_IS_TRAP_HWBKPT and
handle ambiguous GDB_ARCH_IS_TRAP_BRKPT / GDB_ARCH_IS_TRAP_HWBKPT.
Factor out common code between the USE_SIGTRAP_SIGINFO and
!USE_SIGTRAP_SIGINFO blocks.
(linux_low_filter_event): Call save_stop_reason instead of
check_stopped_by_breakpoint and check_stopped_by_watchpoint.
Update comments.
(linux_wait_1): Update comments.
New bnds fields will be always present for x86 architecture.
Fixup for compatibility layer 32bits has to be fixed.
It was added the nat_siginfo to serving as intermediate step
between kernel provided siginfo and the fix up routine.
When executing compat_siginfo_from_siginfo or
compat_x32_siginfo_from_siginfo first the buffer read from the kernel are
converted into the nat_signfo for homogenization, then the fields of
nat_siginfo are use to set the compat and compat_x32 siginfo fields.
In other to make this conversion independent of the system where gdb
is compiled the most complete version of the siginfo, named as native
siginfo, is used internally as an intermediate step.
Conversion using nat_siginfo is exemplified below:
compat_siginfo_from_siginfo or compat_x32_siginfo_from_siginfo:
buffer (from the kernel) -> nat_siginfo -> 32 / X32 siginfo
(memcpy) (field by field)
siginfo_from_compat_x32_siginfo or siginfo_from_compat_siginfo:
32 / X32 siginfo -> nat_siginfo -> buffer (to the kernel)
(field by field) (memcpy)
Caveat: No support for MPX on x32.
2016-02-02 Walfred Tedeschi <walfred.tedeschi@intel.com>
gdb/ChangeLog:
* amd64-linux-siginfo.c (nat_siginfo_t, nat_sigval_t, nat_timeval):
New types.
(compat_siginfo): New bound fields added.
(compat_x32_siginfo): New field added.
(cpt_si_addr_lsb): New define.
(compat_siginfo_from_siginfo): Use nat_siginfo.
(siginfo_from_compat_siginfo): Use nat_siginfo.
(compat_x32_siginfo_from_siginfo): Likewise.
(siginfo_from_compat_x32_siginfo): Likewise.
This commit fixes nat/linux-namespaces.c to build correctly on
targets without fork.
gdb/ChangeLog:
* nat/linux-namespaces.c (do_fork): New function.
(linux_mntns_get_helper): Use the above.
gdb/gdbserver/ChangeLog:
* configure.ac (AC_FUNC_FORK): New check.
* config.in: Regenerate.
* configure: Likewise.
This patch fixes the following GDB build error in C++ mode.
gdb/nat/linux-ptrace.c: In function 'int linux_child_function(void*)':
gdb/nat/linux-ptrace.c:323:65: error: invalid conversion from 'void*' to 'gdb_byte* {aka unsigned char*}' [-fpermissive]
linux_fork_to_function (child_stack, linux_grandchild_function);
^
gdb:
2016-01-12 Yao Qi <yao.qi@linaro.org>
* nat/linux-ptrace.c (linux_child_function): Cast child_stack
to gdb_byte * and pass to linux_fork_to_function.
I see the following compile error with an old bfin-uclinux gcc to
build GDBserver,
cc1: warnings being treated as errors
gdb/gdbserver/../nat/linux-ptrace.c: In function 'linux_fork_to_function':
gdb/gdbserver/../nat/linux-ptrace.c:283: error: passing argument 1 of 'clone' from incompatible pointer type
in glibc, clone's prototype is like this, and in uClibc, it is the same,
int clone(int (*fn)(void *), void *child_stack,
int flags, void *arg, ...
/* pid_t *ptid, struct user_desc *tls, pid_t *ctid */ );
so this patch changes function signature from 'void (*function) (gdb_byte *)'
to 'int (*function) (void *)'.
Note that I find Pedro advised to change argument type from 'void *'
to 'gdb_byte *' during the patch review
https://sourceware.org/ml/gdb-patches/2013-08/msg00611.html however,
I think fix compile error can justify the change back to 'void *'.
gdb:
2016-01-12 Yao Qi <yao.qi@linaro.org>
* nat/linux-ptrace.c (linux_fork_to_function): Change type
of argument 'function'.
(linux_grandchild_function): Change return type to 'int'.
Change child_stack's type to 'void *'.
(linux_child_function): Likewise.
The GNU Coding Standards say:
"Please do not include any trademark acknowledgements in GNU
software packages or documentation."
gdb/ChangeLog:
2016-01-12 Pedro Alves <palves@redhat.com>
Remove use of the registered trademark symbol throughout.
gdb/gdbserver/ChangeLog:
2016-01-12 Pedro Alves <palves@redhat.com>
Remove use of the registered trademark symbol throughout.
gdb/doc/ChangeLog:
2016-01-12 Pedro Alves <palves@redhat.com>
Remove use of the registered trademark symbol throughout.
Since we now rely on PTRACE_EVENT_CLONE being available (added in
Linux 2.5.46), we're relying on NPTL.
This commit removes the support for older LinuxThreads, as well as the
workarounds for vendor 2.4 kernels with NPTL backported.
- Rely on tkill being available.
- Assume gdb doesn't get cancel signals.
- Remove code that checks the LinuxThreads restart and cancel signals
in the inferior.
- Assume that __WALL is available.
- Assume that non-leader threads report WIFEXITED.
- Thus, no longer need to send signal 0 to check whether threads are
still alive.
- Update comments throughout.
Tested on x86_64 Fedora 20, native and gdbserver.
gdb/ChangeLog:
* configure.ac: Remove tkill checks.
* configure, config.in: Regenerate.
* linux-nat.c: Remove HAVE_TKILL_SYSCALL check. Update top level
comments.
(linux_nat_post_attach_wait): Remove 'cloned' parameter. Use
__WALL.
(attach_proc_task_lwp_callback): Don't set the cloned flag.
(linux_nat_attach): Adjust.
(kill_lwp): Remove HAVE_TKILL_SYSCALL check. No longer fall back
to 'kill'.
(linux_handle_extended_wait): Use __WALL. Don't set the cloned
flag.
(wait_lwp): Use __WALL. Update comments.
(running_callback, stop_and_resume_callback): Delete.
(linux_nat_filter_event): Don't stop and resume all lwps. Don't
check if the event LWP has previously exited.
(check_zombie_leaders): Update comments.
(linux_nat_wait_1): Use __WALL.
(kill_wait_callback): Don't handle clone processes separately.
Use __WALL instead.
(linux_thread_alive): Delete.
(linux_nat_thread_alive): Return true as long as the LWP is in the
LWP list.
(linux_nat_update_thread_list): Assume the kernel supports
PTRACE_EVENT_CLONE.
(get_signo): Delete.
(lin_thread_get_thread_signals): Remove LinuxThreads references.
No longer check __pthread_sig_restart / __pthread_sig_cancel in
the inferior.
* linux-nat.h (struct lwp_info) <cloned>: Delete field.
* linux-thread-db.c: Update comments.
(_initialize_thread_db): Remove LinuxThreads references.
* nat/linux-waitpid.c (my_waitpid): No longer emulate __WALL.
Pass down flags unmodified.
* linux-waitpid.h (my_waitpid): Update documentation.
gdb/gdbserver/ChangeLog:
* linux-low.c (linux_kill_one_lwp): Remove references to
LinuxThreads.
(kill_lwp): Remove HAVE_TKILL_SYSCALL check. No longer fall back
to 'kill'.
(linux_init_signals): Delete.
(initialize_low): Adjust.
* thread-db.c (thread_db_init): Remove LinuxThreads reference.
This patch fixes the GDB internal error on AArch64 when running
watchpoint-fork.exp
top?bt 15
internal_error (file=file@entry=0x79d558 "../../binutils-gdb/gdb/linux-nat.c", line=line@entry=4866, fmt=0x793b20 "%s: Assertion `%s' failed.")
at ../../binutils-gdb/gdb/common/errors.c:51
#1 0x0000000000495bc4 in linux_nat_thread_address_space (t=<optimized out>, ptid=<error reading variable: Cannot access memory at address 0x1302>)
at ../../binutils-gdb/gdb/linux-nat.c:4866
#2 0x00000000005db2c8 in delegate_thread_address_space (self=<optimized out>, arg1=<error reading variable: Cannot access memory at address 0x1302>)
at ../../binutils-gdb/gdb/target-delegates.c:2447
#3 0x00000000005e8c7c in target_thread_address_space (ptid=<error reading variable: Cannot access memory at address 0x1302>)
at ../../binutils-gdb/gdb/target.c:2727
#4 0x000000000054eef8 in get_thread_arch_regcache (ptid=..., gdbarch=0xad51e0) at ../../binutils-gdb/gdb/regcache.c:529
#5 0x000000000054efcc in get_thread_regcache (ptid=...) at ../../binutils-gdb/gdb/regcache.c:546
#6 0x000000000054f120 in get_thread_regcache_for_ptid (ptid=...) at ../../binutils-gdb/gdb/regcache.c:560
#7 0x00000000004a2278 in aarch64_point_is_aligned (is_watchpoint=0, addr=34168, len=2) at ../../binutils-gdb/gdb/nat/aarch64-linux-hw-point.c:122
#8 0x00000000004a2e68 in aarch64_handle_breakpoint (type=hw_execute, addr=34168, len=2, is_insert=0, state=0xae8880)
at ../../binutils-gdb/gdb/nat/aarch64-linux-hw-point.c:465
#9 0x000000000048edf0 in aarch64_linux_remove_hw_breakpoint (self=<optimized out>, gdbarch=<optimized out>, bp_tgt=<optimized out>)
at ../../binutils-gdb/gdb/aarch64-linux-nat.c:657
#10 0x00000000005da8dc in delegate_remove_hw_breakpoint (self=<optimized out>, arg1=<optimized out>, arg2=<optimized out>)
at ../../binutils-gdb/gdb/target-delegates.c:492
#11 0x0000000000536a24 in bkpt_remove_location (bl=<optimized out>) at ../../binutils-gdb/gdb/breakpoint.c:13065
#12 0x000000000053351c in remove_breakpoint_1 (bl=0xb3fe70, is=is@entry=mark_inserted) at ../../binutils-gdb/gdb/breakpoint.c:4026
#13 0x000000000053ccc0 in detach_breakpoints (ptid=...) at ../../binutils-gdb/gdb/breakpoint.c:3930
#14 0x00000000005a3ac0 in handle_inferior_event_1 (ecs=0x7ffffff048) at ../../binutils-gdb/gdb/infrun.c:5042
After the fork, GDB will physically remove the breakpoints from the child
process (in frame #14), but at that time, GDB doesn't create an inferior
yet for child, but inferior_ptid is set to child's ptid (in frame #13).
In aarch64_point_is_aligned, we'll get the regcache of current_lwp_ptid
to determine if the current process is 32-bit or 64-bit, so the inferior
can't be found, and the internal error is caused.
I don't find a better fix other than not checking alignment on removing
breakpoint.
gdb:
2015-11-27 Yao Qi <yao.qi@linaro.org>
* nat/aarch64-linux-hw-point.c (aarch64_dr_state_remove_one_point):
Don't assert on alignment.
(aarch64_handle_breakpoint): Only check alignment when IS_INSERT
is true.
This patch adds support for thread names in the remote protocol, and
updates gdb/gdbserver to use it. The information is added to the XML
description sent in response to the qXfer:threads:read packet.
gdb/ChangeLog:
* linux-nat.c (linux_nat_thread_name): Replace implementation by call
to linux_proc_tid_get_name.
* nat/linux-procfs.c (linux_proc_tid_get_name): New function,
implementation inspired by linux_nat_thread_name.
* nat/linux-procfs.h (linux_proc_tid_get_name): New declaration.
* remote.c (struct private_thread_info) <name>: New field.
(free_private_thread_info): Free name field.
(remote_thread_name): New function.
(thread_item_t) <name>: New field.
(clear_threads_listing_context): Free name field.
(start_thread): Get name xml attribute.
(thread_attributes): Add "name" attribute.
(remote_update_thread_list): Copy name field.
(init_remote_ops): Assign remote_thread_name callback.
* target.h (target_thread_name): Update comment.
* NEWS: Mention remote thread name support.
gdb/gdbserver/ChangeLog:
* linux-low.c (linux_target_ops): Use linux_proc_tid_get_name.
* server.c (handle_qxfer_threads_worker): Refactor to include thread
name in reply.
* target.h (struct target_ops) <thread_name>: New field.
(target_thread_name): New macro.
gdb/doc/ChangeLog:
* gdb.texinfo (Thread List Format): Mention thread names.
There is this build failure when building in C++:
/home/simark/src/binutils-gdb/gdb/nat/aarch64-linux-hw-point.c: In function ‘void aarch64_linux_set_debug_regs(const aarch64_debug_reg_state*, int, int)’:
/home/simark/src/binutils-gdb/gdb/nat/aarch64-linux-hw-point.c:564:64: error: ‘count’ cannot appear in a constant-expression
iov.iov_len = (offsetof (struct user_hwdebug_state, dbg_regs[count - 1])
^
We can simplify the computation and make g++ happy at the same time by
formulating as:
size of fixed part + size of variable part
thus...
size of fixed part + count * size of one variable part element
thus...
offsetof (struct user_hwdebug_state, dbg_regs) + count * sizeof (regs.dbg_reg[0]);
gdb/ChangeLog:
* nat/aarch64-linux-hw-point.c (aarch64_linux_set_debug_regs): Change
form of iov_len computation.
gdb/ChangeLog:
* nat/linux-nat.h (__SIGRTMIN): Move here from gdbserver/linux-low.c.
gdb/gdbserver/ChangeLog:
* linux-low.c (__SIGRTMIN): Move to nat/linux-nat.h.
Nowadays, both aarch64 GDB and linux kernel assumes that address for
setting breakpoint should be 4-byte aligned. However that is not true
after we support multi-arch, because thumb instruction can be at 2-byte
aligned address. Patch http://lists.infradead.org/pipermail/linux-arm-kernel/2015-October/375141.html
to linux kernel is to teach kernel to handle 2-byte aligned address for
HW breakpoint, while this patch is to teach aarch64 GDB handle 2-byte
aligned address.
First of all, we call gdbarch_breakpoint_from_pc to get the instruction
length rather than using hard-coded 4. Secondly, in GDBserver, we set
length back to 2 if it is 3, because GDB encode 3 in it to indicate it
is a 32-bit thumb breakpoint. Then we relax the address alignment
check from 4-byte aligned to 2-byte aligned.
This patch enables some tests (such as gdb.base/break-idempotent.exp,
gdb.base/cond-eval-mode.exp, gdb.base/watchpoint-reuse-slot.exp,) and
fixes many fails (such as gdb.base/hbreak2.exp) when the program is
compiled in thumb mode on aarch64.
Regression tested on aarch64-linux, both native and gdbserver. This
is the last patch of multi-arch work.
gdb:
2015-10-15 Yao Qi <yao.qi@linaro.org>
* aarch64-linux-nat.c (aarch64_linux_insert_hw_breakpoint):
Call gdbarch_breakpoint_from_pc to instruction length.
(aarch64_linux_remove_hw_breakpoint): Likewise.
* common/common-regcache.h (regcache_register_size): Declare.
* nat/aarch64-linux-hw-point.c: Include "common-regcache.h".
(aarch64_point_is_aligned): Set alignment to 2 for breakpoint if
the process is 32bit, otherwise set alignment to 4.
(aarch64_handle_breakpoint): Update comments.
* regcache.c (regcache_register_size): New function.
gdb/gdbserver:
2015-10-15 Yao Qi <yao.qi@linaro.org>
* linux-aarch64-low.c (aarch64_insert_point): Set len to 2
if it is 3.
(aarch64_remove_point): Likewise.
* regcache.c (regcache_register_size): New function.
With the kernle fix <http://lists.infradead.org/pipermail/linux-arm-kernel/2015-July/356511.html>,
aarch64 GDB is able to read the base of thread area of 32-bit arm
program through NT_ARM_TLS.
This patch is to teach both GDB and GDBserver to read the base of
thread area correctly in the multi-arch case. A new function
aarch64_ps_get_thread_area is added, and is shared between GDB and
GDBserver.
With this patch applied, the following fails in multi-arch testing
(GDB is aarch64 but the test cases are arm) are fixed,
-FAIL: gdb.threads/tls-nodebug.exp: thread local storage
-FAIL: gdb.threads/tls-shared.exp: print thread local storage variable
-FAIL: gdb.threads/tls-so_extern.exp: print thread local storage variable
-FAIL: gdb.threads/tls-var.exp: print tls_var
-FAIL: gdb.threads/tls.exp: first thread local storage
-FAIL: gdb.threads/tls.exp: first another thread local storage
-FAIL: gdb.threads/tls.exp: p a_thread_local
-FAIL: gdb.threads/tls.exp: p file2_thread_local
-FAIL: gdb.threads/tls.exp: p a_thread_local second time
gdb:
2015-09-18 Yao Qi <yao.qi@linaro.org>
* nat/aarch64-linux.c: Include elf/common.h,
nat/gdb_ptrace.h, asm/ptrace.h and sys/uio.h.
(aarch64_ps_get_thread_area): New function.
* nat/aarch64-linux.h: Include gdb_proc_service.h.
(aarch64_ps_get_thread_area): Declare.
* aarch64-linux-nat.c (ps_get_thread_area): Call
aarch64_ps_get_thread_area.
gdb/gdbserver:
2015-09-18 Yao Qi <yao.qi@linaro.org>
* linux-aarch64-low.c: Don't include sys/uio.h.
(ps_get_thread_area): Call aarch64_ps_get_thread_area.
This patch is to fixup the siginfo_t when aarch64 gdb or gdbserver
read from or write to the arm inferior. It is to convert the
"struct siginfo_t" between aarch64 and arm, which is quite mechanical.
gdb/gdbserver:
2015-09-15 Yao Qi <yao.qi@linaro.org>
* linux-aarch64-low.c (aarch64_linux_siginfo_fixup): New
function.
(struct linux_target_ops the_low_target): Install
aarch64_linux_siginfo_fixup.
gdb:
2015-09-15 Yao Qi <yao.qi@linaro.org>
* aarch64-linux-nat.c (aarch64_linux_siginfo_fixup): New function.
(_initialize_aarch64_linux_nat): Call linux_nat_set_siginfo_fixup.
* nat/aarch64-linux.c (aarch64_compat_siginfo_from_siginfo):
New function.
(aarch64_siginfo_from_compat_siginfo): New function.
* nat/aarch64-linux.h: Include signal.h.
(compat_int_t, compat_uptr_t, compat_time_t): Typedef.
(compat_timer_t, compat_clock_t): Likewise.
(struct compat_timeval): New.
(union compat_sigval): New.
(struct compat_siginfo): New.
(cpt_si_pid, cpt_si_uid, cpt_si_timerid): New macros.
(cpt_si_overrun, cpt_si_status, cpt_si_utime): Likewise.
(cpt_si_stime, cpt_si_ptr, cpt_si_addr): Likewise.
(cpt_si_band, cpt_si_fd): Likewise.
This patch implements support for exec events on extended-remote Linux
targets. Follow-exec-mode and rerun behave as expected. Catchpoints and
test updates are implemented in subsequent patches.
This patch was derived from a patch posted last October:
https://sourceware.org/ml/gdb-patches/2014-10/msg00877.html.
It was originally based on some work done by Luis Machado in 2013.
IMPLEMENTATION
----------------
Exec events are enabled via ptrace options.
When an exec event is detected by gdbserver, the existing process
data, along with all its associated lwp and thread data, is deleted
and replaced by data for a new single-threaded process. The new
process data is initialized with the appropriate parts of the state
of the execing process. This approach takes care of several potential
pitfalls, including:
* deleting the data for an execing non-leader thread before any
wait/sigsuspend occurs
* correctly initializing the architecture of the execed process
We then report the exec event using a new RSP stop reason, "exec".
When GDB receives an "exec" event, it saves the status in the event
structure's target_waitstatus field, like what is done for remote fork
events. Because the original and execed programs may have different
architectures, we skip parsing the section of the stop reply packet
that contains register data. The register data will be retrieved
later after the inferior's architecture has been set up by
infrun.c:follow_exec.
At that point the exec event is handled by the existing event handling
in GDB. However, a few changes were necessary so that
infrun.c:follow_exec could accommodate the remote target.
* Where follow-exec-mode "new" is handled, we now call
add_inferior_with_spaces instead of add_inferior with separate calls
to set up the program and address spaces. The motivation for this
is that add_inferior_with_spaces also sets up the initial architecture
for the inferior, which is needed later by target_find_description
when it calls target_gdbarch.
* We call a new target function, target_follow_exec. This function
allows us to store the execd_pathname in the inferior, instead of
using the static string remote_exec_file from remote.c. The static
string didn't work for follow-exec-mode "new", since once you switched
to the execed program, the original remote exec-file was lost. The
execd_pathname is now stored in the inferior's program space as a
REGISTRY field. All of the requisite mechanisms for this are
defined in remote.c.
gdb/gdbserver/ChangeLog:
* linux-low.c (linux_mourn): Static declaration.
(linux_arch_setup): Move in front of
handle_extended_wait.
(linux_arch_setup_thread): New function.
(handle_extended_wait): Handle exec events. Call
linux_arch_setup_thread. Make event_lwp argument a
pointer-to-a-pointer.
(check_zombie_leaders): Do not check stopped threads.
(linux_low_ptrace_options): Add PTRACE_O_TRACEEXEC.
(linux_low_filter_event): Add lwp and thread for exec'ing
non-leader thread if leader thread has been deleted.
Refactor code into linux_arch_setup_thread and call it.
Pass child lwp pointer by reference to handle_extended_wait.
(linux_wait_for_event_filtered): Update comment.
(linux_wait_1): Prevent clobbering exec event status.
(linux_supports_exec_events): New function.
(linux_target_ops) <supports_exec_events>: Initialize new member.
* lynx-low.c (lynx_target_ops) <supports_exec_events>: Initialize
new member.
* remote-utils.c (prepare_resume_reply): New stop reason 'exec'.
* server.c (report_exec_events): New global variable.
(handle_query): Handle qSupported query for exec-events feature.
(captured_main): Initialize report_exec_events.
* server.h (report_exec_events): Declare new global variable.
* target.h (struct target_ops) <supports_exec_events>: New
member.
(target_supports_exec_events): New macro.
* win32-low.c (win32_target_ops) <supports_exec_events>:
Initialize new member.
gdb/ChangeLog:
* infrun.c (follow_exec): Use process-style ptid for
exec message. Call add_inferior_with_spaces and
target_follow_exec.
* nat/linux-ptrace.c (linux_supports_traceexec): New function.
* nat/linux-ptrace.h (linux_supports_traceexec): Declare.
* remote.c (remote_pspace_data): New static variable.
(remote_pspace_data_cleanup): New function.
(get_remote_exec_file): New function.
(set_remote_exec_file_1): New function.
(set_remote_exec_file): New function.
(show_remote_exec_file): New function.
(remote_exec_file): Delete static variable.
(anonymous enum) <PACKET_exec_event_feature> New
enumeration constant.
(remote_protocol_features): Add entry for exec-events feature.
(remote_query_supported): Add client side of qSupported query
for exec-events feature.
(remote_follow_exec): New function.
(remote_parse_stop_reply): Handle 'exec' stop reason.
(extended_remote_run, extended_remote_create_inferior): Call
get_remote_exec_file and set_remote_exec_file_1.
(init_extended_remote_ops) <to_follow_exec>: Initialize new
member.
(_initialize_remote): Call
register_program_space_data_with_cleanup. Call
add_packet_config_cmd for remote exec-events feature.
Modify call to add_setshow_string_noescape_cmd for exec-file
to use new functions set_remote_exec_file and
show_remote_exec_file.
* target-debug.h, target-delegates.c: Regenerated.
* target.c (target_follow_exec): New function.
* target.h (struct target_ops) <to_follow_exec>: New member.
(target_follow_exec): Declare new function.
For the BTS recording format, we sometimes get a FROM->TO record where the
FROM address lies in the kernel and the TO address lies in user space at
whatever address the user process was resumed.
GDB has a heuristic to filter out such records based on looking at the most
significant bit in the PC. This works fine for 64-bit systems but it doesn't
always work for 32-bit systems. Libraries that are loaded at fairly high
addresses might be mistaken for kernel code and branches inside the library
are filtered out.
Change the heuristic to (again heuristically) try to determine the lowest
address in kernel space. Any PC that is smaller than that should be in
user space.
On today's systems, there should be a symbol "_text" at that address.
Read /proc/kallsyms and search for that symbol.
It is not guaranteed that /proc/kallsyms is readable on all systems. On
64-bit systems, we fall back to check the most significant bit. On 32-bit
systems, we refrain from filtering out addresses.
The filtering should really be done by the kernel. And it soon will be:
https://lkml.org/lkml/2015/8/31/212.
gdb/
* nat/linux-btrace.h (struct btrace_target_info) <ptr_bits>: Remove.
* nat/linux-btrace.c: Include filestuff.h and inttypes.h.
Remove include of sys/utsname.h.
(linux_determine_kernel_ptr_bits): Remove.
(linux_determine_kernel_start): New.
(perf_event_is_kernel_addr): Remove tinfo argument. Update users.
Update check.
(perf_event_skip_bts_record): Remove tinfo argument. Update users.
(linux_enable_bts, linux_enable_pt): Remove tinfo->ptr_bits
initialization.
* x86-linux-nat.c (x86_linux_enable_btrace): Remove ptr_bits
assignment.
gdbserver/
* linux-low.c (linux_low_enable_btrace): Remove.
(linux_target_ops): Replace linux_low_enable_btrace with
linux_enable_btrace.
Nowadays, if user requests HW watchpoint to monitor a large memory area
or unaligned area, aarch64 GDB will split into multiple aligned areas,
and use multiple debugging registers to watch them. However, the
registers are not updated in a transaction way. GDBserver doesn't revert
updates in previous iterations if some debugging registers fail to update
due to some reason, like no free debugging registers available, in the
latter iteration. For example, if we have a char buf[34], and watch buf
in gdb,
(gdb) watch buf
Hardware watchpoint 2: buf
(gdb) c
Continuing.
infrun: clear_proceed_status_thread (Thread 13466)
infrun: proceed (addr=0xffffffffffffffff, signal=GDB_SIGNAL_DEFAULT)
infrun: step-over queue now empty
infrun: resuming [Thread 13466] for step-over
Sending packet: $m410838,22#35...Packet received: 00000000000000000000000000000000000000000000000000000000000000000000
infrun: skipping breakpoint: stepping past insn at: 0x400524
infrun: skipping breakpoint: stepping past insn at: 0x400524
Sending packet: $Z2,410838,22#80...Packet received: E01 <----- [1]
Packet Z2 (write-watchpoint) is supported
Sending packet: $Z0,7fb7fe0a8c,4#43...Packet received: OK
Warning:
Could not insert hardware watchpoint 2.
Could not insert hardware breakpoints:
You may have requested too many hardware breakpoints/watchpoints.
GDB receives E01 for Z2 packet [1] but GDBserver updates the debugging
register status,
insert_point (addr=0x00410838, len=34, type=hw-write-watchpoint):
BREAKPOINTs:
BP0: addr=0x0, ctrl=0x00000000, ref.count=0
BP1: addr=0x0, ctrl=0x00000000, ref.count=0
BP2: addr=0x0, ctrl=0x00000000, ref.count=0
BP3: addr=0x0, ctrl=0x00000000, ref.count=0
BP4: addr=0x0, ctrl=0x00000000, ref.count=0
BP5: addr=0x0, ctrl=0x00000000, ref.count=0
WATCHPOINTs:
WP0: addr=0x410850, ctrl=0x00001ff5, ref.count=1
WP1: addr=0x410848, ctrl=0x00001ff5, ref.count=1
WP2: addr=0x410840, ctrl=0x00001ff5, ref.count=1
WP3: addr=0x410838, ctrl=0x00001ff5, ref.count=1
four debugging registers can not monitor 34-byte long area, so the last
iteration of updating debugging register state fails but previous
iterations succeed. This makes GDB think no HW watchpoint is inserted
but some debugging registers are used.
This problem was exposed by "watch buf" gdb.base/watchpoint.exp with
aarch64 GDBserver debugging arm 32-bit program. The buf is 30-byte long
but 4-byte aligned, and four debugging registers can't cover 34-byte
(extend 4 bytes to be 8-byte aligned) area. However, this problem
does exist on non-multi-arch debugging scenario as well.
This patch moves code in aarch64_linux_region_ok_for_hw_watchpoint to
aarch64_linux_region_ok_for_watchpoint in nat/aarch64-linux-hw-point.c.
Then, checks with aarch64_linux_region_ok_for_watchpoint, like what we
are doing in GDB. If the region is OK, call aarch64_handle_watchpoint.
Regression tested on aarch64 with both 64-bit program and 32-bit
program. Some fails in gdb.base/watchpoint.exp are fixed.
gdb:
2015-09-03 Yao Qi <yao.qi@linaro.org>
* aarch64-linux-nat.c (aarch64_linux_region_ok_for_hw_watchpoint):
Move code to aarch64_linux_region_ok_for_watchpoint. Call
aarch64_linux_region_ok_for_watchpoint.
* nat/aarch64-linux-hw-point.c (aarch64_linux_region_ok_for_watchpoint):
New function.
* nat/aarch64-linux-hw-point.h (aarch64_linux_region_ok_for_watchpoint):
Declare it.
gdb/gdbserver:
2015-09-03 Yao Qi <yao.qi@linaro.org>
* linux-aarch64-low.c (aarch64_insert_point): Call
aarch64_handle_watchpoint if aarch64_linux_region_ok_for_watchpoint
returns true.
The Linux target and gdbserver now check the siginfo si_code
reported on a SIGTRAP to detect whether the trap indicates
a software breakpoint was hit.
Unfortunately, on Cell/B.E., the kernel uses an si_code value
of TRAP_BRKPT when a SW breakpoint was hit in PowerPC code,
but a si_code value of SI_KERNEL when a SW breakpoint was
hit in SPU code.
This patch updates Linux target and gdbserver to accept both
si_code values to indicate SW breakpoint on PowerPC.
ChangeLog:
* nat/linux-ptrace.h (GDB_ARCH_TRAP_BRKPT): Replace by ...
(GDB_ARCH_IS_TRAP_BRKPT): ... this. Add __powerpc__ case.
* linux-nat.c (check_stopped_by_breakpoint): Use
GDB_ARCH_IS_TRAP_BRKPT instead of GDB_ARCH_TRAP_BRKPT.
gdbserver/ChangeLog:
* linux-low.c (check_stopped_by_breakpoint): Use
GDB_ARCH_IS_TRAP_BRKPT instead of GDB_ARCH_TRAP_BRKPT.
In debug_reg_change_callback, we change debug registers of each LWP.
It makes more sense to print LWP's pid rather than group leader's pid.
gdb:
2015-08-25 Yao Qi <yao.qi@linaro.org>
* nat/aarch64-linux-hw-point.c (debug_reg_change_callback):
Rename local variable pid to tid, and get lwpid of lwp. Update
debug output.
This patch moves aarch64_linux_new_thread in GDB and GDBserver to
nat/aarch64-linux.c.
gdb:
2015-08-25 Yao Qi <yao.qi@linaro.org>
* aarch64-linux-nat.c (aarch64_linux_new_thread): Move it to ...
* nat/aarch64-linux.c (aarch64_linux_new_thread): ... here.
* nat/aarch64-linux.h (aarch64_linux_new_thread): Declare.
gdb/gdbserver:
2015-08-25 Yao Qi <yao.qi@linaro.org>
* linux-aarch64-low.c (aarch64_linux_new_thread): Remove.
This commit fixes a stale cleanup left by linux_mntns_access_fs.
gdb/ChangeLog:
* nat/linux-namespaces.c (linux_mntns_access_fs):
Do not overwrite old_chain.
Running gdbserver --debug under Valgrind shows:
==4803== Invalid read of size 4
==4803== at 0x432B62: linux_write_memory (linux-low.c:5320)
==4803== by 0x4143F7: write_inferior_memory (target.c:83)
==4803== by 0x415895: remove_memory_breakpoint (mem-break.c:362)
==4803== by 0x432EF5: linux_remove_point (linux-low.c:5460)
==4803== by 0x416319: delete_raw_breakpoint (mem-break.c:802)
==4803== by 0x4163F3: release_breakpoint (mem-break.c:842)
==4803== by 0x416477: delete_breakpoint_1 (mem-break.c:869)
==4803== by 0x4164EF: delete_breakpoint (mem-break.c:891)
==4803== by 0x416843: delete_gdb_breakpoint_1 (mem-break.c:1069)
==4803== by 0x4168D8: delete_gdb_breakpoint (mem-break.c:1098)
==4803== by 0x4134E3: process_serial_event (server.c:4051)
==4803== by 0x4138E4: handle_serial_event (server.c:4196)
==4803== Address 0x4c6b930 is 0 bytes inside a block of size 1 alloc'd
==4803== at 0x4A0645D: malloc (in /usr/lib64/valgrind/vgpreload_memcheck-amd64-linux.so)
==4803== by 0x4240C6: xmalloc (common-utils.c:43)
==4803== by 0x41439C: write_inferior_memory (target.c:80)
==4803== by 0x415895: remove_memory_breakpoint (mem-break.c:362)
==4803== by 0x432EF5: linux_remove_point (linux-low.c:5460)
==4803== by 0x416319: delete_raw_breakpoint (mem-break.c:802)
==4803== by 0x4163F3: release_breakpoint (mem-break.c:842)
==4803== by 0x416477: delete_breakpoint_1 (mem-break.c:869)
==4803== by 0x4164EF: delete_breakpoint (mem-break.c:891)
==4803== by 0x416843: delete_gdb_breakpoint_1 (mem-break.c:1069)
==4803== by 0x4168D8: delete_gdb_breakpoint (mem-break.c:1098)
==4803== by 0x4134E3: process_serial_event (server.c:4051)
==4803==
And:
==7272== Conditional jump or move depends on uninitialised value(s)
==7272== at 0x3615E48361: vfprintf (vfprintf.c:1634)
==7272== by 0x414E89: debug_vprintf (debug.c:60)
==7272== by 0x42800A: debug_printf (common-debug.c:35)
==7272== by 0x43937B: my_waitpid (linux-waitpid.c:149)
==7272== by 0x42D740: linux_wait_for_event_filtered (linux-low.c:2441)
==7272== by 0x42DADA: linux_wait_for_event (linux-low.c:2552)
==7272== by 0x42E165: linux_wait_1 (linux-low.c:2860)
==7272== by 0x42F5D8: linux_wait (linux-low.c:3453)
==7272== by 0x4144A4: mywait (target.c:107)
==7272== by 0x413969: handle_target_event (server.c:4214)
==7272== by 0x41A1A6: handle_file_event (event-loop.c:429)
==7272== by 0x41996D: process_event (event-loop.c:184)
gdb/ChangeLog:
2015-08-06 Pedro Alves <palves@redhat.com>
* nat/linux-waitpid.c (my_waitpid): Only print *status if waitpid
returned > 0.
gdb/gdbserver/ChangeLog:
2015-08-06 Pedro Alves <palves@redhat.com>
* linux-low.c (linux_write_memory): Rewrite debug output to avoid
reading beyond the passed in buffer length.
Fixes a build error due to typedef redefinition with some compilers.
Also added missing copyright header.
gdb/
* nat/gdb_thread_db.h: Add copyright header.
Protect against multiple inclusion.
Implicit void * -> function pointer conversion doesn't work in C++, so
in C++, we need to cast the result of dlsym. This adds a few typedefs
and macros that make this easy. GDBserver's version already had the
CHK macro, so I added it to GDB too.
Tested on x86_64 Fedora 20, native and gdbserver.
gdb/gdbserver/ChangeLog:
2015-08-04 Pedro Alves <palves@redhat.com>
* thread-db.c (struct thread_db): Use new typedefs.
(try_thread_db_load_1): Define local TDB_DLSYM macro and use it in
CHK calls.
(disable_thread_event_reporting): Cast result of dlsym to
destination function pointer type.
(thread_db_mourn): Use td_ta_delete_ftype.
gdb/ChangeLog:
2015-08-04 Pedro Alves <palves@redhat.com>
* nat/gdb_thread_db.h (td_init_ftype, td_ta_new_ftype)
(td_ta_map_lwp2thr_ftype, td_ta_thr_iter_ftype)
(td_ta_event_addr_ftype, td_ta_set_event_ftype)
(td_ta_clear_event_ftype, td_ta_event_getmsg_ftype)
(td_thr_validate_ftype, td_thr_get_info_ftype)
(td_thr_event_enable_ftype, td_thr_tls_get_addr_ftype)
(td_thr_tlsbase_ftype, td_symbol_list_ftype, td_ta_delete_ftype):
New typedefs.
* linux-thread-db.c (struct thread_db_info): Use new typedefs.
(try_thread_db_load_1): Define TDB_VERBOSE_DLSYM, TDB_DLSYM , CHK
local macros and use them instead of verbose_dlsym and dlsym
calls.
Since Pedro's ptrace cleanups, the MIPS buildbot compilation fails.
Code in MIPS native uses ptrace with 3 arguments, where ptrace requires
4. When looking at the definition of ptrace in
/usr/include/sys/ptrace.h, it shows that it takes a variable number of
arguments. The wrapper macro in nat/gdb_ptrace.h takes a fixed number
of arguments (4). That would explain why it used to work and stopped.
I am pushing this as obvious, tell me if there is any problem.
I built-tested this with a MIPS toolchain (ct-ng), but I don't have any
setup to test it. At least it should put back the buildbot builder in a
better shape.
gdb/ChangeLog:
* mips-linux-nat.c (write_watchpoint_regs): Add NULL as ptrace's 4th
parameter.
(mips_linux_new_thread): Likewise.
* nat/mips-linux-watch.c (mips_linux_read_watch_registers): Likewise.
gdb/gdbserver/ChangeLog:
* linux-mips-low.c (mips_linux_prepare_to_resume): Add NULL as
ptrace's 4th parameter.
Building in C++ mode issues ~40 warnings like this:
../../src/gdb/linux-nat.c: In function ‘int linux_handle_extended_wait(lwp_info*, int, int)’:
../../src/gdb/linux-nat.c:2016:51: warning: invalid conversion from ‘int’ to ‘__ptrace_request’ [-fpermissive]
ptrace (PTRACE_GETEVENTMSG, pid, 0, &new_pid);
The issue is that in glibc, ptrace's first parameter is an enum.
That's not a problem if we pick the PTRACE_XXX requests from
sys/ptrace.h, as those will be values of the corresponding enum.
However, we have fallback definitions for PTRACE_XXX symbols when the
system headers miss them (such as PTRACE_GETEVENTMSG above), and those
are plain integer constants. E.g., nat/linux-ptrace.h:
#define PTRACE_GETEVENTMSG 0x4201
One idea would be to fix this by defining those fallbacks like:
-#define PTRACE_GETEVENTMSG 0x4201
+#define PTRACE_GETEVENTMSG ((enum __ptrace_request) 0x4201)
However, while glibc's ptrace uses enum __ptrace_request for first
parameter:
extern long int ptrace (enum __ptrace_request __request, ...) __THROW;
other libc's, like e.g., Android's bionic do not -- in that case, the
first parameter is int:
long ptrace(int request, pid_t pid, void * addr, void * data);
So the fix I came up is to make configure/ptrace.m4 also detect the
type of the ptrace's first parameter and defin PTRACE_TYPE_ARG1, as
already does the for parameters 3-4, and then simply wrap ptrace with
a macro that casts the first argument to the detected type. (I'm
leaving adding a nicer wrapper for when we drop building in C).
While this adds the wrapper, GNU/Linux files won't use it until the
next patch, which makes all native GNU/Linux files include
gdb_ptrace.h.
gdb/ChangeLog:
2015-07-24 Pedro Alves <palves@redhat.com>
* ptrace.m4 (ptrace tests): Test in C++ mode. Try with 'enum
__ptrace_request as first parameter type instead of int.
(PTRACE_TYPE_ARG1): Define.
* nat/gdb_ptrace.h [!PTRACE_TYPE_ARG5] (ptrace): Define as wrapper
that casts first argument to PTRACE_TYPE_ARG1.
* config.in: Regenerate.
* configure: Regenerate.
gdb/gdbserver/ChangeLog:
2015-07-24 Pedro Alves <palves@redhat.com>
* config.in: Regenerate.
* configure: Regenerate.
Now that gdbserver's configure defines PTRACE_TYPE_ARGx etc., we'll be
able to make gdbserver use gdb_ptrace.h too. Move it to the native
target files directory.
gdb/ChangeLog:
2015-07-24 Pedro Alves <palves@redhat.com>
* gdb_ptrace.h: Move ...
* nat/gdb_ptrace.h: ... here.
* inf-ptrace.c: Adjust.
There are also some duplication on getting HW watchpoint/breakpoint
registers info between GDB and GDBserver. This patch moves them
to nat/aarch64-linux-hw-point.c.
Note that ENABLE_NLS is not defined in GDBserver, so it should be OK
to use _( markup.
gdb:
2015-07-21 Yao Qi <yao.qi@linaro.org>
* aarch64-linux-nat.c (aarch64_linux_get_debug_reg_capacity):
Move it to nat/aarch64-linux-hw-point.c.
(aarch64_linux_child_post_startup_inferior): Update.
* nat/aarch64-linux-hw-point.c (aarch64_linux_get_debug_reg_capacity):
New function.
* nat/aarch64-linux-hw-point.h (aarch64_linux_get_debug_reg_capacity):
Declare it.
gdb/gdbserver:
2015-07-21 Yao Qi <yao.qi@linaro.org>
* linux-aarch64-low.c (aarch64_arch_setup): Remove code and call
aarch64_linux_get_debug_reg_capacity.
This patch is to fix two ARI warnings for nat/aarch64-linux-hw-point.{c,h}.
gdb:
2015-07-20 Yao Qi <yao.qi@linaro.org>
* nat/aarch64-linux-hw-point.c (aarch64_handle_unaligned_watchpoint):
Re-indent the code.
* nat/aarch64-linux-hw-point.h: Use ULONGEST rather than
"unsigned long long".
When I look at test fails related to watchpoint on aarch64-linux,
I find there are some code duplicates between GDB and GDBserver.
This patch is to move some of them to a nat/aarch64-linux-hw-point.{h,c}.
The only change I do is about the dr_changed_t typedef, which was
ULONGEST in GDB and 'unsigned long long' in GDBserver. Each bit
of dr_changed_t represents a status of each HW breakpoint or
watchpoint register, and the max number of HW breakpoint or watchpoint
registers is 16, so the width of 'unsigned long long' is sufficient.
gdb:
2015-07-17 Yao Qi <yao.qi@linaro.org>
* Makefile.in (HFILES_NO_SRCDIR): Add
nat/aarch64-linux-hw-point.h.
(aarch64-linux-hw-point.o): New rule.
* nat/aarch64-linux-hw-point.h: New file.
* nat/aarch64-linux-hw-point.c: New file.
* aarch64-linux-nat.c: Include nat/aarch64-linux-hw-point.h.
(AARCH64_HBP_MAX_NUM): Move to nat/aarch64-linux-hw-point.h.
(AARCH64_HWP_MAX_NUM, AARCH64_HBP_ALIGNMENT): Likewise.
(AARCH64_HWP_ALIGNMENT): Likewise.
(AARCH64_HWP_MAX_LEN_PER_REG): Likewise.
(AARCH64_DEBUG_NUM_SLOTS, AARCH64_DEBUG_ARCH): Likewise.
(AARCH64_DEBUG_ARCH_V8, DR_MARK_ALL_CHANGED): Likewise.
(DR_MARK_N_CHANGED, DR_CLEAR_CHANGED): Likewise.
(DR_HAS_CHANGED, DR_N_HAS_CHANGE): Likewise.
(aarch64_num_bp_regs, aarch64_num_wp_regs): Likewise.
(struct aarch64_debug_reg_state): Likewise.
(struct arch_lwp_info): Likewise.
(aarch64_linux_set_debug_regs): Likewise.
(aarch64_notify_debug_reg_change): Remove static.
(aarch64_align_watchpoint): Likewise.
(DR_CONTROL_ENABLED, DR_CONTROL_LENGTH): Likewise.
(aarch64_watchpoint_length): Likewise.
(aarch64_point_encode_ctrl_reg): Likewise
(aarch64_point_is_aligned): Likewise.
(aarch64_dr_state_insert_one_point): Likewise.
(aarch64_dr_state_remove_one_point): Likewise.
(aarch64_handle_breakpoint): Likewise.
(aarch64_handle_aligned_watchpoint): Likewise.
(aarch64_handle_unaligned_watchpoint): Likewise.
(aarch64_handle_watchpoint): Likewise.
* config/aarch64/linux.mh (NAT_FILE): Add
aarch64-linux-hw-point.o.
gdb/gdbserver:
2015-07-17 Yao Qi <yao.qi@linaro.org>
* Makefile.in (aarch64-linux-hw-point.o): New rule.
* configure.srv (srv_tgtobj): Append aarch64-linux-hw-point.o.
* linux-aarch64-low.c: Include nat/aarch64-linux-hw-point.h.
(AARCH64_HBP_MAX_NUM): Move to nat/aarch64-linux-hw-point.h.
(AARCH64_HWP_MAX_NUM, AARCH64_HBP_ALIGNMENT): Likewise.
(AARCH64_HWP_ALIGNMENT): Likewise.
(AARCH64_HWP_MAX_LEN_PER_REG): Likewise.
(AARCH64_DEBUG_NUM_SLOTS, AARCH64_DEBUG_ARCH): Likewise.
(aarch64_num_bp_regs, aarch64_num_wp_regs): Likewise.
(AARCH64_DEBUG_ARCH_V8, DR_MARK_ALL_CHANGED): Likewise.
(DR_MARK_N_CHANGED, DR_CLEAR_CHANGED): Likewise.
(DR_HAS_CHANGED, DR_N_HAS_CHANGE): Likewise.
(struct aarch64_debug_reg_state): Likewise.
(struct arch_lwp_info): Likewise.
(aarch64_align_watchpoint): Likewise.
(DR_CONTROL_ENABLED, DR_CONTROL_LENGTH): Likewise.
(aarch64_watchpoint_length): Likewise.
(aarch64_point_encode_ctrl_reg): Likewise
(aarch64_point_is_aligned): Likewise.
(aarch64_align_watchpoint): Likewise.
(aarch64_linux_set_debug_regs):
(aarch64_dr_state_insert_one_point): Likewise.
(aarch64_dr_state_remove_one_point): Likewise.
(aarch64_handle_breakpoint): Likewise.
(aarch64_handle_aligned_watchpoint): Likewise.
(aarch64_handle_unaligned_watchpoint): Likewise.
(aarch64_handle_watchpoint): Likewise.
This should be just a move with no changes.
gdb/ChangeLog
2015-07-15 Aleksandar Ristovski <aristovski@qnx.com
Jan Kratochvil <jan.kratochvil@redhat.com>
Move linux_find_memory_regions_full & co.
* linux-tdep.c (nat/linux-maps.h): Include.
(gdb_regex.h): Remove the include.
(enum filterflags, struct smaps_vmflags, read_mapping, decode_vmflags)
(mapping_is_anonymous_p, dump_mapping_p): Moved to nat/linux-maps.c.
(linux_find_memory_region_ftype): Moved typedef to nat/linux-maps.h.
(linux_find_memory_regions_full): Moved definition to nat/linux-maps.c.
* nat/linux-maps.c: Include ctype.h, target/target-utils.h, gdb_regex.h
and target/target.h.
(struct smaps_vmflags, read_mapping, decode_vmflags)
(mapping_is_anonymous_p, dump_mapping_p): Move from linux-tdep.c.
(linux_find_memory_regions_full): Move from linux-tdep.c.
* nat/linux-maps.h (read_mapping): New declaration.
(linux_find_memory_region_ftype, enum filterflags): Moved from
linux-tdep.c.
(linux_find_memory_regions_full): New declaration.
* target.c (target/target-utils.h): Include.
(read_alloc_pread_ftype): Moved typedef to target/target-utils.h.
(read_alloc, read_stralloc_func_ftype, read_stralloc): Moved
definitions to target/target-utils.c.
* target.h (target_fileio_read_stralloc): Move it to target/target.h.
* target/target-utils.c (read_alloc, read_stralloc): Move definitions
from target.c.
* target/target-utils.h (read_alloc_pread_ftype): New typedef.
(read_alloc): New declaration.
(read_stralloc_func_ftype): New typedef.
(read_stralloc): New declaration.
* target/target.h (target_fileio_read_stralloc): Move it from target.h.
gdb/gdbserver/ChangeLog
2015-07-15 Aleksandar Ristovski <aristovski@qnx.com
Jan Kratochvil <jan.kratochvil@redhat.com>
* target.c: Include target/target-utils.h and fcntl.h.
(target_fileio_read_stralloc_1_pread, target_fileio_read_stralloc_1)
(target_fileio_read_stralloc): New functions.
Fix the ARI warning about the use of unsigned long long. We can't use
ULONGEST as this is defined unsigned long on 64-bit systems. This will
result in a compile error when storing a pointer to an unsigned long long
structure field (declared in perf_event.h as __u64) in a ULONGEST * variable.
Use size_t to hold the buffer size inside GDB and __u64 when interfacing the
Linux kernel.
gdb/
* nat/linux-btrace.c (perf_event_read): Change the type of DATA_HEAD.
(perf_event_read_all): Change the type of SIZE and DATA_HEAD.
(perf_event_read_bts): Change the type of SIZE and READ.
(linux_enable_bts): Change the type of SIZE, PAGES, DATA_SIZE,
and DATA_OFFSET. Move DATA_SIZE declaration. Restrict the buffer size
to UINT_MAX. Check for overflows when using DATA_HEAD from the perf
mmap page.
(linux_enable_pt): Change the type of PAGES and SIZE. Restrict the
buffer size to UINT_MAX.
(linux_read_bts): Change the type of BUFFER_SIZE, SIZE, DATA_HEAD, and
DATA_TAIL.
* nat/linux-btrace.h (struct perf_event_buffer)<size, data_head>
<last_head>: Change type.
* common/btrace-common.h (struct btrace_dat_pt) <size>: Change type.
* common/btrace-common.c (btrace_data_append): Change the type of
SIZE.
* btrace.c (parse_xml_raw): Change the type of SIZE. Change oddness
check.
* nat/linux-namespaces.c (setns): Rename from this ...
(do_setns): ... to this. Support calling setns if it exists.
(mnsh_handle_setns): Call do_setns.
Do not use strerror(), instead use safe_strerror().
gdb/
* nat/linux-btrace.c (kernel_supports_bts, kernel_supports_pt):
Use safe_strerror() instead of strerror().
In struct perf_event_mmap_page there are new fields data_size and data_offset
that give the location of the perf_event data buffer relative to the mmap
page. Use them if they are present.
gdb/
* nat/linux-btrace.c (linux_enable_bts): Check for
PERF_ATTR_SIZE_VER5.
Check for data_offset and data_size fields. Use them.
Adds a new command "record btrace pt" to configure the kernel to use
Intel(R) Processor Trace instead of Branch Trace Strore.
The "record btrace" command chooses the tracing format automatically.
Intel(R) Processor Trace support requires Linux 4.1 and libipt.
gdb/
* NEWS: Announce new commands "record btrace pt" and "record pt".
Announce new options "set|show record btrace pt buffer-size".
* btrace.c: Include "rsp-low.h".
Include "inttypes.h".
(btrace_add_pc): Add forward declaration.
(pt_reclassify_insn, ftrace_add_pt, btrace_pt_readmem_callback)
(pt_translate_cpu_vendor, btrace_finalize_ftrace_pt)
(btrace_compute_ftrace_pt): New.
(btrace_compute_ftrace): Support BTRACE_FORMAT_PT.
(check_xml_btrace_version): Update version check.
(parse_xml_raw, parse_xml_btrace_pt_config_cpu)
(parse_xml_btrace_pt_raw, parse_xml_btrace_pt)
(btrace_pt_config_cpu_attributes, btrace_pt_config_children)
(btrace_pt_children): New.
(btrace_children): Add support for "pt".
(parse_xml_btrace_conf_pt, btrace_conf_pt_attributes): New.
(btrace_conf_children): Add support for "pt".
* btrace.h: Include "intel-pt.h".
(btrace_pt_error): New.
* common/btrace-common.c (btrace_format_string, btrace_data_fini)
(btrace_data_empty): Support BTRACE_FORMAT_PT.
* common/btrace-common.h (btrace_format): Add BTRACE_FORMAT_PT.
(struct btrace_config_pt): New.
(struct btrace_config)<pt>: New.
(struct btrace_data_pt_config, struct btrace_data_pt): New.
(struct btrace_data)<pt>: New.
* features/btrace-conf.dtd (btrace-conf)<pt>: New.
(pt): New.
* features/btrace.dtd (btrace)<pt>: New.
(pt, pt-config, cpu): New.
* nat/linux-btrace.c (perf_event_read, perf_event_read_all)
(perf_event_pt_event_type, kernel_supports_pt)
(linux_supports_pt): New.
(linux_supports_btrace): Support BTRACE_FORMAT_PT.
(linux_enable_bts): Free tinfo on error.
(linux_enable_pt): New.
(linux_enable_btrace): Support BTRACE_FORMAT_PT.
(linux_disable_pt): New.
(linux_disable_btrace): Support BTRACE_FORMAT_PT.
(linux_fill_btrace_pt_config, linux_read_pt): New.
(linux_read_btrace): Support BTRACE_FORMAT_PT.
* nat/linux-btrace.h (struct btrace_tinfo_pt): New.
(struct btrace_target_info)<pt>: New.
* record-btrace.c (set_record_btrace_pt_cmdlist)
(show_record_btrace_pt_cmdlist): New.
(record_btrace_print_pt_conf): New.
(record_btrace_print_conf): Support BTRACE_FORMAT_PT.
(btrace_ui_out_decode_error): Support BTRACE_FORMAT_PT.
(cmd_record_btrace_pt_start): New.
(cmd_record_btrace_start): Support BTRACE_FORMAT_PT.
(cmd_set_record_btrace_pt, cmd_show_record_btrace_pt): New.
(_initialize_record_btrace): Add new commands.
* remote.c (PACKET_Qbtrace_pt, PACKET_Qbtrace_conf_pt_size): New.
(remote_protocol_features): Add "Qbtrace:pt".
Add "Qbtrace-conf:pt:size".
(remote_supports_btrace): Support BTRACE_FORMAT_PT.
(btrace_sync_conf): Support PACKET_Qbtrace_conf_pt_size.
(remote_enable_btrace): Support BTRACE_FORMAT_PT.
(_initialize_remote): Add new commands.
gdbserver/
* linux-low.c: Include "rsp-low.h"
(linux_low_encode_pt_config, linux_low_encode_raw): New.
(linux_low_read_btrace): Support BTRACE_FORMAT_PT.
(linux_low_btrace_conf): Support BTRACE_FORMAT_PT.
(handle_btrace_enable_pt): New.
(handle_btrace_general_set): Support "pt".
(handle_btrace_conf_general_set): Support "pt:size".
doc/
* gdb.texinfo (Process Record and Replay): Spell out that variables
and registers are not available during btrace replay.
Describe the new "record btrace pt" command.
Describe the new "set|show record btrace pt buffer-size" options.
(General Query Packets): Describe the new Qbtrace:pt and
Qbtrace-conf:pt:size packets.
Expand "bts" to "Branch Trace Store".
Update the branch trace DTD.
stdint.h was added to common-defs.h some months ago and should
no longer be included directly by any file.
gdb_assert.h was added to common-defs.h nearly a year ago, but
three includes have crept in since then.
This commit removes all such redundant include directives.
gdb/ChangeLog:
* common/buffer.c (stdint.h): Do not include.
* common/print-utils.c (stdint.h): Likewise.
* compile/compile-c-symbols.c (gdb_assert.h): Likewise.
* compile/compile-c-types.c (gdb_assert.h): Likewise.
* ft32-tdep.c (gdb_assert.h): Likewise.
* guile/scm-utils.c (stdint.h): Likewise.
* i386-linux-tdep.c (stdint.h): Likewise.
* i386-tdep.c (stdint.h): Likewise.
* nat/linux-btrace.c (stdint.h): Likewise.
* nat/linux-btrace.h (stdint.h): Likewise.
* nat/linux-ptrace.c (stdint.h): Likewise.
* nat/mips-linux-watch.h (stdint.h): Likewise.
* ppc-linux-nat.c (stdint.h): Likewise.
* python/python-internal.h (stdint.h): Likewise.
* stub-termcap.c (stdlib.h): Likewise.
* target/target.h (stdint.h): Likewise.
* xtensa-linux-nat.c (stdint.h): Likewise.
gdb/gdbserver/ChangeLog:
* linux-i386-ipa.c (stdint.h): Do not include.
* lynx-i386-low.c (stdint.h): Likewise.
* lynx-ppc-low.c (stdint.h): Likewise.
* mem-break.c (stdint.h): Likewise.
* thread-db.c (stdint.h): Likewise.
* tracepoint.c (stdint.h): Likewise.
* win32-low.c (stdint.h): Likewise.
This commit changes the debug printing code in linux-namespaces.c
to use pulongest instead of "%ld".
gdb/ChangeLog:
* nat/linux-namespaces.c (mnsh_send_message): Use pulongest.
(mnsh_recv_message): Likewise.
This commit fixes the following ARI warning:
gdb/nat/linux-namespaces.c:28: regression: Do not include
wait.h or sys/wait.h, instead include gdb_wait.h
gdb/ChangeLog:
* nat/linux-namespaces.c (gdb_wait.h): New include.
(sys/wait.h): Do not include.
This commit removes linux_proc_pid_get_ns, and updates its only
caller to use linux_ns_same instead.
gdb/ChangeLog:
* linux-thread-db.c (nat/linux-namespaces.h): New include.
(check_pid_namespace_match): Use linux_ns_same rather than
linux_proc_pid_get_ns to spot PID namespace mismatches.
* nat/linux-procfs.h (linux_proc_pid_get_ns): Remove.
* nat/linux-procfs.c (linux_proc_pid_get_ns): Likewise.
Macros PTRACE_GETREGSET and PTRACE_SETREGSET are defined locally in
some places in GDB and GDBserver. This patch is to move them to
nat/linux-ptrace.h to avoid duplication.
gdb:
2015-06-01 Yao Qi <yao.qi@linaro.org>
* amd64-linux-nat.c: Include "nat/linux-ptrace.h".
* i386-linux-nat.c: Likewise.
* nat/linux-ptrace.h (PTRACE_GETREGSET, PTRACE_SETREGSET): Define.
* s390-linux-nat.c: Include "nat/linux-ptrace.h".
(PTRACE_GETREGSET, PTRACE_SETREGSET): Remove.
* x86-linux-nat.c: Include "nat/linux-ptrace.h".
* x86-linux-nat.h (PTRACE_GETREGSET, PTRACE_SETREGSET): Remove.
gdb/gdbserver:
2015-06-01 Yao Qi <yao.qi@linaro.org>
* linux-s390-low.c (PTRACE_GETREGSET, PTRACE_SETREGSET): Remove.
* linux-x86-low.c: Likewise.
Building in C++ mode errors with:
~~~
g++ -fpermissive (...) /home/pedro/gdb/mygit/src/gdb/gdbserver/../nat/x86-linux.c
In file included from /home/pedro/gdb/mygit/src/gdb/gdbserver/../nat/x86-linux.h:23:0,
from /home/pedro/gdb/mygit/src/gdb/gdbserver/../nat/x86-linux.c:21:
/home/pedro/gdb/mygit/src/gdb/gdbserver/../nat/linux-nat.h:74:13: error: use of enum ‘target_stop_reason’ without previous declaration
extern enum target_stop_reason lwp_stop_reason (struct lwp_info *lwp);
^
/home/pedro/gdb/mygit/src/gdb/gdbserver/../nat/linux-nat.h:74:70: error: invalid type in declaration before ‘;’ token
extern enum target_stop_reason lwp_stop_reason (struct lwp_info *lwp);
^
~~~
gdb/ChangeLog:
2015-05-15 Pedro Alves <palves@redhat.com>
* nat/linux-nat.h: Include "target/waitstatus.h".
This patch implements basic support for follow-fork and detach-on-fork on
extended-remote Linux targets. Only 'fork' is supported in this patch;
'vfork' support is added n a subsequent patch. This patch depends on
the previous patches in the patch series.
Sufficient extended-remote functionality has been implemented here to pass
gdb.base/multi-forks.exp, as well as gdb.base/foll-fork.exp with the
catchpoint tests commented out. Some other fork tests fail with this
patch because it doesn't provide the architecture support needed for
watchpoint inheritance or fork catchpoints.
The implementation follows the same general structure as for the native
implementation as much as possible.
This implementation includes:
* enabling fork events in linux-low.c in initialize_low and
linux_enable_extended_features
* handling fork events in gdbserver/linux-low.c:handle_extended_wait
- when a fork event occurs in gdbserver, we must do the full creation
of the new process, thread, lwp, and breakpoint lists. This is
required whether or not the new child is destined to be
detached-on-fork, because GDB will make target calls that require all
the structures. In particular we need the breakpoint lists in order
to remove the breakpoints from a detaching child. If we are not
detaching the child we will need all these structures anyway.
- as part of this event handling we store the target_waitstatus in a new
member of the parent lwp_info structure, 'waitstatus'. This
is used to store extended event information for reporting to GDB.
- handle_extended_wait is given a return value, denoting whether the
handled event should be reported to GDB. Previously it had only
handled clone events, which were never reported.
* using a new predicate in gdbserver to control handling of the fork event
(and eventually all extended events) in linux_wait_1. The predicate,
extended_event_reported, checks a target_waitstatus.kind for an
extended ptrace event.
* implementing a new RSP 'T' Stop Reply Packet stop reason: "fork", in
gdbserver/remote-utils.c and remote.c.
* implementing new target and RSP support for target_follow_fork with
target extended-remote. (The RSP components were actually defined in
patch 1, but they see their first use here).
- remote target routine remote_follow_fork, which just sends the 'D;pid'
detach packet to detach the new fork child cleanly. We can't just
call target_detach because the data structures for the forked child
have not been allocated on the host side.
Tested on x64 Ubuntu Lucid, native, remote, extended-remote.
gdb/gdbserver/ChangeLog:
* linux-low.c (handle_extended_wait): Implement return value,
rename argument 'event_child' to 'event_lwp', handle
PTRACE_EVENT_FORK, call internal_error for unrecognized event.
(linux_low_ptrace_options): New function.
(linux_low_filter_event): Call linux_low_ptrace_options,
use different argument fo linux_enable_event_reporting,
use return value from handle_extended_wait.
(extended_event_reported): New function.
(linux_wait_1): Call extended_event_reported and set
status to report fork events.
(linux_write_memory): Add pid to debug message.
(reset_lwp_ptrace_options_callback): New function.
(linux_handle_new_gdb_connection): New function.
(linux_target_ops): Initialize new structure member.
* linux-low.h (struct lwp_info) <waitstatus>: New member.
* lynx-low.c: Initialize new structure member.
* remote-utils.c (prepare_resume_reply): Implement stop reason
"fork" for "T" stop message.
* server.c (handle_query): Call handle_new_gdb_connection.
* server.h (report_fork_events): Declare global flag.
* target.h (struct target_ops) <handle_new_gdb_connection>:
New member.
(target_handle_new_gdb_connection): New macro.
* win32-low.c: Initialize new structure member.
gdb/ChangeLog:
* linux-nat.c (linux_nat_ptrace_options): New function.
(linux_init_ptrace, wait_lwp, linux_nat_filter_event):
Call linux_nat_ptrace_options and use different argument to
linux_enable_event_reporting.
(_initialize_linux_nat): Delete call to
linux_ptrace_set_additional_flags.
* nat/linux-ptrace.c (current_ptrace_options): Rename to
supported_ptrace_options.
(additional_flags): Delete variable.
(linux_check_ptrace_features): Use supported_ptrace_options.
(linux_test_for_tracesysgood, linux_test_for_tracefork):
Likewise, and remove additional_flags check.
(linux_enable_event_reporting): Change 'attached' argument to
'options'. Use supported_ptrace_options.
(ptrace_supports_feature): Change comment. Use
supported_ptrace_options.
(linux_ptrace_set_additional_flags): Delete function.
* nat/linux-ptrace.h (linux_ptrace_set_additional_flags):
Delete function prototype.
* remote.c (remote_fork_event_p): New function.
(remote_detach_pid): New function.
(remote_detach_1): Call remote_detach_pid, don't mourn inferior
if doing detach-on-fork.
(remote_follow_fork): New function.
(remote_parse_stop_reply): Handle new "T" stop reason "fork".
(remote_pid_to_str): Print "process" strings for pid/0/0 ptids.
(init_extended_remote_ops): Initialize to_follow_fork.
This patch implements a mechanism for GDB to determine whether fork
events are supported in gdbserver. This is a preparatory patch for
remote fork and exec event support.
Two new RSP packets are defined to represent fork and vfork event
support. These packets are used just like PACKET_multiprocess_feature
to denote whether the corresponding event is supported. GDB sends
fork-events+ and vfork-events+ to gdbserver to inquire about fork
event support. If the response enables these packets, then GDB
knows that gdbserver supports the corresponding events and will
enable them.
Target functions used to query for support are included along with
each new packet.
In order for gdbserver to know whether the events are supported at the
point where the qSupported packet arrives, the code in nat/linux-ptrace.c
had to be reorganized. Previously it would test for fork/exec event
support, then enable the events using the pid of the inferior. When the
qSupported packet arrives there may not be an inferior. So the mechanism
was split into two parts: a function that checks whether the events are
supported, called when gdbserver starts up, and another that enables the
events when the inferior stops for the first time.
Another gdbserver change was to add some global variables similar to
multi_process, one per new packet. These are used to control whether
the corresponding fork events are enabled. If GDB does not inquire
about the event support in the qSupported packet, then gdbserver will
not set these "report the event" flags. If the flags are not set, the
events are ignored like they were in the past. Thus, gdbserver will
never send fork event notification to an older GDB that doesn't
recognize fork events.
Tested on Ubuntu x64, native/remote/extended-remote, and as part of
subsequent patches in the series.
gdb/gdbserver/ChangeLog:
* linux-low.c (linux_supports_fork_events): New function.
(linux_supports_vfork_events): New function.
(linux_target_ops): Initialize new structure members.
(initialize_low): Call linux_check_ptrace_features.
* lynx-low.c (lynx_target_ops): Initialize new structure
members.
* server.c (report_fork_events, report_vfork_events):
New global flags.
(handle_query): Add new features to qSupported packet and
response.
(captured_main): Initialize new global variables.
* target.h (struct target_ops) <supports_fork_events>:
New member.
<supports_vfork_events>: New member.
(target_supports_fork_events): New macro.
(target_supports_vfork_events): New macro.
* win32-low.c (win32_target_ops): Initialize new structure
members.
gdb/ChangeLog:
* nat/linux-ptrace.c (linux_check_ptrace_features): Change
from static to extern.
* nat/linux-ptrace.h (linux_check_ptrace_features): Declare.
* remote.c (anonymous enum): <PACKET_fork_event_feature,
* PACKET_vfork_event_feature>: New enumeration constants.
(remote_protocol_features): Add table entries for new packets.
(remote_query_supported): Add new feature queries to qSupported
packet.
(_initialize_remote): Exempt new packets from the requirement
to have 'set remote' commands.
This commit introduces a new function linux_proc_pid_to_exec_file
that shared Linux code can use to discover the filename of the
executable that was run to create a process on the system.
gdb/ChangeLog:
* nat/linux-procfs.h (linux_proc_pid_to_exec_file):
New declaration.
* nat/linux-procfs.c (linux_proc_pid_to_exec_file):
New function, factored out from...
* linux-nat.c (linux_child_pid_to_exec_file): ...here.
This patch adds cpu information on linux based on /proc/cpuinfo as :
cpus Listing of all cpus/cores on the system
This patch also reorders the info os commands so that they are listed
in alphabetical order.
gdb/ChangeLog:
* NEWS: Mention info os cpus support.
* gdb/nat/linux-osdata.c (linux_xfer_osdata_cpus): New function.
(struct osdata_type): Add cpus entry, reorder the entries in
alphabetical order.
gdb/doc/ChangeLog:
* gdb.texinfo (Operating System Auxiliary Information): Add info os cpus
documentation, reorder the info os entries in alphabetical order.
This commit moves two identical functions from gdb/x86-linux-nat.c and
gdb/gdbserver/linux-x86-low.c into the shared file gdb/nat/x86-linux.c.
gdb/ChangeLog:
* nat/x86-linux.h (x86_linux_new_thread): New declaration.
(x86_linux_prepare_to_resume): Likewise.
* x86-linux-nat.c (x86_linux_new_thread):
Moved to nat/x86-linux.c.
(x86_linux_prepare_to_resume): Likewise.
* nat/x86-linux.c (x86_linux_new_thread): New function.
(x86_linux_prepare_to_resume): Likewise.
gdb/gdbserver/ChangeLog:
* linux-x86-low.c (x86_linux_new_thread): Moved to
nat/x86-linux.c.
(x86_linux_prepare_to_resume): Likewise.
This commit moves the code to handle lwp_info.arch_private for
Linux x86 into a new shared file, nat/x86-linux.c.
gdb/ChangeLog:
* nat/x86-linux.h: New file.
* nat/x86-linux.c: Likewise.
* Makefile.in (HFILES_NO_SRCDIR): Add nat/x86-linux.h.
(x86-linux.o): New rule.
* config/i386/linux.mh (NATDEPFILES): Add x86-linux.o.
* config/i386/linux64.mh (NATDEPFILES): Likewise.
* nat/linux-nat.h (struct arch_lwp_info): New forward declaration.
(lwp_set_arch_private_info): New declaration.
(lwp_arch_private_info): Likewise.
* linux-nat.c (lwp_set_arch_private_info): New function.
(lwp_arch_private_info): Likewise.
* x86-linux-nat.c: Include nat/x86-linux.h.
(arch_lwp_info): Removed structure.
(update_debug_registers_callback):
Use lwp_set_debug_registers_changed.
(x86_linux_prepare_to_resume): Use lwp_debug_registers_changed
and lwp_set_debug_registers_changed.
(x86_linux_new_thread): Use lwp_set_debug_registers_changed.
gdb/gdbserver/ChangeLog:
* Makefile.in (x86-linux.o): New rule.
* configure.srv: Add x86-linux.o to relevant targets.
* linux-low.c (lwp_set_arch_private_info): New function.
(lwp_arch_private_info): Likewise.
* linux-x86-low.c: Include nat/x86-linux.h.
(arch_lwp_info): Removed structure.
(update_debug_registers_callback):
Use lwp_set_debug_registers_changed.
(x86_linux_prepare_to_resume): Use lwp_debug_registers_changed
and lwp_set_debug_registers_changed.
(x86_linux_new_thread): Use lwp_set_debug_registers_changed.
This commit introduces three accessors that shared Linux code can
use to access fields of struct lwp_info. The GDB and gdbserver
Linux x86 code is modified to use them.
gdb/ChangeLog:
* nat/linux-nat.h (ptid_of_lwp): New declaration.
(lwp_is_stopped): Likewise.
(lwp_stop_reason): Likewise.
* linux-nat.c (ptid_of_lwp): New function.
(lwp_is_stopped): Likewise.
(lwp_is_stopped_by_watchpoint): Likewise.
* x86-linux-nat.c (update_debug_registers_callback):
Use lwp_is_stopped.
(x86_linux_prepare_to_resume): Use ptid_of_lwp and
lwp_stop_reason.
gdb/gdbserver/ChangeLog:
* linux-low.c (ptid_of_lwp): New function.
(lwp_is_stopped): Likewise.
(lwp_stop_reason): Likewise.
* linux-x86-low.c (update_debug_registers_callback):
Use lwp_is_stopped.
(x86_linux_prepare_to_resume): Use ptid_of_lwp and
lwp_stop_reason.
Both GDB and gdbserver had linux_stop_lwp functions with identical
declarations. This commit moves these to nat/linux-nat.h to allow
shared code to use the function.
gdb/ChangeLog:
* linux-nat.h (linux_stop_lwp): Move declaration to...
* nat/linux-nat.h (linux_stop_lwp): New declaration.
gdb/gdbserver/ChangeLog:
* linux-low.h (linux_stop_lwp): Remove declaration.
This commit introduces a new function, iterate_over_lwps, that
shared Linux code can use to call a function for each LWP that
matches certain criteria. This function already existed in GDB
and was in use by GDB's various low-level Linux x86 debug register
setters. An equivalent was written for gdbserver and gdbserver's
low-level Linux x86 debug register setters were modified to use
it.
gdb/ChangeLog:
* linux-nat.h: Include nat/linux-nat.h.
(iterate_over_lwps): Move declaration to nat/linux-nat.h.
* nat/linux-nat.h (struct lwp_info): New forward declaration.
(iterate_over_lwps_ftype): New typedef.
(iterate_over_lwps): New declaration.
* linux-nat.h (iterate_over_lwps): Update comment. Use
iterate_over_lwps_ftype. Update callback return value check.
gdb/gdbserver/ChangeLog:
* linux-low.h: Include nat/linux-nat.h.
* linux-low.c (iterate_over_lwps_args): New structure.
(iterate_over_lwps_filter): New function.
(iterate_over_lwps): Likewise.
* linux-x86-low.c (update_debug_registers_callback):
Update signature to what iterate_over_lwps expects.
Remove PID check that iterate_over_lwps now performs.
(x86_dr_low_set_addr): Use iterate_over_lwps.
(x86_dr_low_set_control): Likewise.
This commit introduces a new function, x86_debug_reg_state, that
shared x86 code can use to access the local mirror of a process's
debug registers. This function already existed in GDB and was
in use by GDB's x86_linux_prepare_to_resume. An equivalent was
written for gdbserver and gdbserver's x86_linux_prepare_to_resume
was modified to use it.
gdb/ChangeLog:
* x86-nat.h (x86_debug_reg_state): Move declaration to...
* nat/x86-dregs.h (x86_debug_reg_state): New declaration.
gdb/gdbserver/ChangeLog:
* linux-x86-low.c (x86_debug_reg_state): New function.
(x86_linux_prepare_to_resume): Use the above.
This commit introduces a new function, current_lwp_ptid, that
shared Linux code can use to obtain the ptid of the current
lightweight process.
gdb/ChangeLog:
* nat/linux-nat.h (current_lwp_ptid): New declaration.
* linux-nat.c (current_lwp_ptid): New function.
* x86-linux-nat.c: Include nat/linux-nat.h.
(x86_linux_dr_get_addr): Use current_lwp_ptid.
(x86_linux_dr_get_control): Likewise.
(x86_linux_dr_get_status): Likewise.
(x86_linux_dr_set_control): Likewise.
(x86_linux_dr_set_addr): Likewise.
gdb/gdbserver/ChangeLog:
* linux-low.c (current_lwp_ptid): New function.
* linux-x86-low.c: Include nat/linux-nat.h.
(x86_dr_low_get_addr): Use current_lwp_ptid.
(x86_dr_low_get_control): Likewise.
(x86_dr_low_get_status): Likewise.
On GNU/Linux, this test sometimes FAILs like this:
(gdb) run
Starting program: /home/pedro/gdb/mygit/build/gdb/testsuite/gdb.threads/killed
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib64/libthread_db.so.1".
ptrace: No such process.
(gdb)
Program terminated with signal SIGKILL, Killed.
The program no longer exists.
FAIL: gdb.threads/killed.exp: run program to completion (timeout)
Note the suspicious "No such process" line (that's errno==ESRCH).
Adding debug output we see:
linux_nat_wait: [process -1], [TARGET_WNOHANG]
LLW: enter
LNW: waitpid(-1, ...) returned 18465, ERRNO-OK
LLW: waitpid 18465 received Stopped (signal) (stopped)
LNW: waitpid(-1, ...) returned 18461, ERRNO-OK
LLW: waitpid 18461 received Trace/breakpoint trap (stopped)
LLW: Handling extended status 0x03057f
LHEW: Got clone event from LWP 18461, new child is LWP 18465
LNW: waitpid(-1, ...) returned 0, ERRNO-OK
RSRL: resuming stopped-resumed LWP LWP 18465 at 0x3b36af4b51: step=0
RSRL: resuming stopped-resumed LWP LWP 18461 at 0x3b36af4b51: step=0
sigchld
ptrace: No such process.
(gdb) linux_nat_wait: [process -1], [TARGET_WNOHANG]
LLW: enter
LNW: waitpid(-1, ...) returned 18465, ERRNO-OK
LLW: waitpid 18465 received Killed (terminated)
LLW: LWP 18465 exited.
LNW: waitpid(-1, ...) returned 18461, No child processes
LLW: waitpid 18461 received Killed (terminated)
Process 18461 exited
LNW: waitpid(-1, ...) returned -1, No child processes
LLW: exit
sigchld
infrun: target_wait (-1, status) =
infrun: 18461 [process 18461],
infrun: status->kind = signalled, signal = GDB_SIGNAL_KILL
infrun: TARGET_WAITKIND_SIGNALLED
Program terminated with signal SIGKILL, Killed.
The program no longer exists.
infrun: stop_waiting
FAIL: gdb.threads/killed.exp: run program to completion (timeout)
The issue is that here:
RSRL: resuming stopped-resumed LWP LWP 18465 at 0x3b36af4b51: step=0
RSRL: resuming stopped-resumed LWP LWP 18461 at 0x3b36af4b51: step=0
The first line shows we had just resumed LWP 18465, which does:
void *
child_func (void *dummy)
{
kill (pid, SIGKILL);
exit (1);
}
So if the kernel manages to schedule that thread fast enough, the
process may be killed before GDB has a chance to resume LWP 18461.
GDBserver has code at the tail end of linux_resume_one_lwp to cope
with this:
~~~
ptrace (step ? PTRACE_SINGLESTEP : PTRACE_CONT, lwpid_of (thread),
(PTRACE_TYPE_ARG3) 0,
/* Coerce to a uintptr_t first to avoid potential gcc warning
of coercing an 8 byte integer to a 4 byte pointer. */
(PTRACE_TYPE_ARG4) (uintptr_t) signal);
current_thread = saved_thread;
if (errno)
{
/* ESRCH from ptrace either means that the thread was already
running (an error) or that it is gone (a race condition). If
it's gone, we will get a notification the next time we wait,
so we can ignore the error. We could differentiate these
two, but it's tricky without waiting; the thread still exists
as a zombie, so sending it signal 0 would succeed. So just
ignore ESRCH. */
if (errno == ESRCH)
return;
perror_with_name ("ptrace");
}
~~~
However, that's not a complete fix, because between starting to handle
the resume request and getting that PTRACE_CONTINUE, we run other
ptrace calls that can also fail with ESRCH, and that end up throwing
an error (with perror_with_name).
In the case above, I indeed sometimes see resume_stopped_resumed_lwps
fail in the registers read:
resume_stopped_resumed_lwps (struct lwp_info *lp, void *data)
{
...
CORE_ADDR pc = regcache_read_pc (regcache);
Or e.g., in 32-bit mode, i386_linux_resume has several calls that can
throw too.
Whether to ignore ptrace errors or not depends on context that is only
available somewhere up the call chain. So the fix is to let ptrace
errors throw as they do today, and wrap the resume request in a
TRY/CATCH that swallows it iff the lwp that we were trying to resume
is no longer ptrace-stopped.
gdb/gdbserver/ChangeLog:
2015-03-19 Pedro Alves <palves@redhat.com>
* linux-low.c (linux_resume_one_lwp): Rename to ...
(linux_resume_one_lwp_throw): ... this. Don't handle ESRCH here,
instead call perror_with_name.
(check_ptrace_stopped_lwp_gone): New function.
(linux_resume_one_lwp): Reimplement as wrapper around
linux_resume_one_lwp_throw that swallows errors if the LWP is
gone.
gdb/ChangeLog:
2015-03-19 Pedro Alves <palves@redhat.com>
* linux-nat.c (linux_resume_one_lwp): Rename to ...
(linux_resume_one_lwp_throw): ... this. Don't handle ESRCH here,
instead call perror_with_name.
(check_ptrace_stopped_lwp_gone): New function.
(linux_resume_one_lwp): Reimplement as wrapper around
linux_resume_one_lwp_throw that swallows errors if the LWP is
gone.
(resume_stopped_resumed_lwps): Try register reads in TRY/CATCH and
swallows errors if the LWP is gone. Use
linux_resume_one_lwp_throw instead of linux_resume_one_lwp.
This commit introduces a new inline common function "startswith"
which takes two string arguments and returns nonzero if the first
string starts with the second. It also updates the 295 places
where this logic was written out longhand to use the new function.
gdb/ChangeLog:
* common/common-utils.h (startswith): New inline function.
All places where this logic was used updated to use the above.
This patch adjusts the native Linux target backend to tell the core
whether a trap was caused by a breakpoint.
It teaches the target to get that information out of the si_code of
the SIGTRAP siginfo.
Tested on x86-64 Fedora 20, s390 RHEL 7, and PPC64 Fedora 18. An
earlier version was tested on ARM Fedora 21.
gdb/ChangeLog:
2015-03-04 Pedro Alves <palves@redhat.com>
* linux-nat.c (save_sigtrap): Check for breakpoints before
checking watchpoints.
(status_callback) [USE_SIGTRAP_SIGINFO]: Don't check whether a
breakpoint is inserted if relying on SIGTRAP's siginfo.si_code.
(check_stopped_by_breakpoint) [USE_SIGTRAP_SIGINFO]: Decide whether
a breakpoint triggered based on the SIGTRAP's siginfo.si_code.
(linux_nat_stopped_by_sw_breakpoint)
(linux_nat_supports_stopped_by_sw_breakpoint)
(linux_nat_stopped_by_hw_breakpoint)
(linux_nat_supports_stopped_by_hw_breakpoint): New functions.
(linux_nat_wait_1): Don't re-increment the PC if relying on
SIGTRAP's siginfo->si_code.
(linux_nat_add_target): Install new target methods.
* linux-thread-db.c (check_event): Don't account for breakpoint PC
offset if the target already adjusted the PC.
* nat/linux-ptrace.h (USE_SIGTRAP_SIGINFO): New.
(GDB_ARCH_TRAP_BRKPT): New.
(TRAP_HWBKPT): Define if not already defined.
The heuristic for filtering out kernel addressess in BTS trace checks the
most significant bit in each address. This works fine for 32-bit and 64-bit
mode.
For 32-bit compatibility mode, i.e. a 32-bit inferior running on 64-bit
host, we need to check bit 63 (or any bit bigger than 31), not bit 31.
Use the machine field in struct utsname provided by a uname call to
determine whether we are running on a 64-bit host.
Thanks to Jan Kratochvil for reporting the issue.
gdb/
* nat/linux-btrace.c: Include sys/utsname.h.
(linux_determine_kernel_ptr_bits): New.
(linux_enable_bts): Call linux_determine_kernel_ptr_bits.
* x86-linux-nat.c (x86_linux_enable_btrace): Do not overwrite non-zero
ptr_bits.
gdbserver/
* linux-low.c (linux_low_enable_btrace): Do not overwrite non-zero
ptr_bits.
Can't do that in C++.
2015-02-27 Pedro Alves <palves@redhat.com>
* nat/x86-dregs.h (enum target_hw_bp_type): Remove forward
declaration.
Include break-common.h.
These symbols are defined in C code, so in C++ mode we need to use
extern "C" to declare them. As extern "C" can't be used inside a
function's scope, we move the declarations to the global scope at the
same time.
gdb/ChangeLog:
2015-02-27 Pedro Alves <palves@redhat.com>
* cli-out.c (_rl_erase_entire_line): Move declaration out of
cli_mld_erase_entire_line, and make it extern "C".
* common/common-defs.h (EXTERN_C): New.
* completer.c (_rl_completion_prefix_display_length)
(_rl_print_completions_horizontally, QSFUNC): Move declarations
out of gdb_display_match_list_1.
(_rl_qsort_string_compare): Move declaration out of
gdb_display_match_list_1, and make it extern "C".
* defs.h (re_comp): Use EXTERN_C.
* maint.c (_mcleanup): Move declaration out of mcleanup_wrapper,
and make it extern "C".
(monstartup): Move declaration out of maintenance_set_profile_cmd,
and make it extern "C".
(main): Move declaration out of maintenance_set_profile_cmd.
* nat/linux-ptrace.c (linux_ptrace_attach_fail_reason_string): Use
EXTERN_C.
This patch renames symbols that happen to have names which are
reserved keywords in C++.
Most of this was generated with Tromey's cxx-conversion.el script.
Some places where later hand massaged a bit, to fix formatting, etc.
And this was rebased several times meanwhile, along with re-running
the script, so re-running the script from scratch probably does not
result in the exact same output. I don't think that matters anyway.
gdb/
2015-02-27 Tom Tromey <tromey@redhat.com>
Pedro Alves <palves@redhat.com>
Rename symbols whose names are reserved C++ keywords throughout.
gdb/gdbserver/
2015-02-27 Tom Tromey <tromey@redhat.com>
Pedro Alves <palves@redhat.com>
Rename symbols whose names are reserved C++ keywords throughout.
TL;DR - GDB can hang if something refreshes the thread list out of the
target while the target is running. GDB hangs inside td_ta_thr_iter.
The fix is to not use that libthread_db function anymore.
Long version:
Running the testsuite against my all-stop-on-top-of-non-stop series is
still exposing latent non-stop bugs.
I was originally seeing this with the multi-create.exp test, back when
we were still using libthread_db thread event breakpoints. The
all-stop-on-top-of-non-stop series forces a thread list refresh each
time GDB needs to start stepping over a breakpoint (to pause all
threads). That test hits the thread event breakpoint often, resulting
in a bunch of step-over operations, thus a bunch of thread list
refreshes while some threads in the target are running.
The commit adds a real non-stop mode test that triggers the issue,
based on multi-create.exp, that does an explicit "info threads" when a
breakpoint is hit. IOW, it does the same things the as-ns series was
doing when testing multi-create.exp.
The bug is a race, so it unfortunately takes several runs for the test
to trigger it. In fact, even when setting the test running in a loop,
it sometimes takes several minutes for it to trigger for me.
The race is related to libthread_db's td_ta_thr_iter. This is
libthread_db's entry point for walking the thread list of the
inferior.
Sometimes, when GDB refreshes the thread list from the target,
libthread_db's td_ta_thr_iter can somehow see glibc's thread list as a
cycle, and get stuck in an infinite loop.
The issue is that when a thread exits, its thread control structure in
glibc is moved from a "used" list to a "cache" list. These lists are
simply circular linked lists where the "next/prev" pointers are
embedded in the thread control structure itself. The "next" pointer
of the last element of the list points back to the list's sentinel
"head". There's only one set of "next/prev" pointers for both lists;
thus a thread can only be in one of the lists at a time, not in both
simultaneously.
So when thread C exits, simplifying, the following happens. A-C are
threads. stack_used and stack_cache are the list's heads.
Before:
stack_used -> A -> B -> C -> (&stack_used)
stack_cache -> (&stack_cache)
After:
stack_used -> A -> B -> (&stack_used)
stack_cache -> C -> (&stack_cache)
td_ta_thr_iter starts by iterating at the list's head's next, and
iterates until it sees a thread whose next pointer points to the
list's head again. Thus in the before case above, C's next points to
stack_used, indicating end of list. In the same case, the stack_cache
list is empty.
For each thread being iterated, td_ta_thr_iter reads the whole thread
object out of the inferior. This includes the thread's "next"
pointer.
In the scenario above, it may happen that td_ta_thr_iter is iterating
thread B and has already read B's thread structure just before thread
C exits and its control structure moves to the cached list.
Now, recall that td_ta_thr_iter is running in the context of GDB, and
there's no locking between GDB and the inferior. From it's local copy
of B, td_ta_thr_iter believes that the next thread after B is thread
C, so it happilly continues iterating to C, a thread that has already
exited, and is now in the stack cache list.
After iterating C, td_ta_thr_iter finds the stack_cache head, which
because it is not stack_used, td_ta_thr_iter assumes it's just another
thread. After this, unless the reverse race triggers, GDB gets stuck
in td_ta_thr_iter forever walking the stack_cache list, as no thread
in thatlist has a next pointer that points back to stack_used (the
terminating condition).
Before fully understanding the issue, I tried adding cycle detection
to GDB's td_ta_thr_iter callback. However, td_ta_thr_iter skips
calling the callback in some cases, which means that it's possible
that the callback isn't called at all, making it impossible for GDB to
break the loop. I did manage to get GDB stuck in that state more than
once.
Fortunately, we can avoid the issue altogether. We don't really need
td_ta_thr_iter for live debugging nowadays, given PTRACE_EVENT_CLONE.
We already know how to map and lwp id to a thread id without iterating
(thread_from_lwp), so use that more.
gdb/ChangeLog:
2015-02-20 Pedro Alves <palves@redhat.com>
* linux-nat.c (linux_handle_extended_wait): Call
thread_db_notice_clone whenever a new clone LWP is detected.
(linux_stop_and_wait_all_lwps, linux_unstop_all_lwps): New
functions.
* linux-nat.h (thread_db_attach_lwp): Delete declaration.
(thread_db_notice_clone, linux_stop_and_wait_all_lwps)
(linux_unstop_all_lwps): Declare.
* linux-thread-db.c (struct thread_get_info_inout): Delete.
(thread_get_info_callback): Delete.
(thread_from_lwp): Use td_thr_get_info and record_thread.
(thread_db_attach_lwp): Delete.
(thread_db_notice_clone): New function.
(try_thread_db_load_1): If /proc is mounted and shows the
process'es task list, walk over all LWPs and call thread_from_lwp
instead of relying on td_ta_thr_iter.
(attach_thread): Don't call check_thread_signals here. Split the
tail part of the function (which adds the thread to the core GDB
thread list) to ...
(record_thread): ... this function. Call check_thread_signals
here.
(thread_db_wait): Don't call thread_db_find_new_threads_1. Always
call thread_from_lwp.
(thread_db_update_thread_list): Rename to ...
(thread_db_update_thread_list_org): ... this.
(thread_db_update_thread_list): New function.
(thread_db_find_thread_from_tid): Delete.
(thread_db_get_ada_task_ptid): Simplify.
* nat/linux-procfs.c: Include <sys/stat.h>.
(linux_proc_task_list_dir_exists): New function.
* nat/linux-procfs.h (linux_proc_task_list_dir_exists): Declare.
gdb/gdbserver/ChangeLog:
2015-02-20 Pedro Alves <palves@redhat.com>
* thread-db.c: Include "nat/linux-procfs.h".
(thread_db_init): Skip listing new threads if the kernel supports
PTRACE_EVENT_CLONE and /proc/PID/task/ is accessible.
gdb/testsuite/ChangeLog:
2015-02-20 Pedro Alves <palves@redhat.com>
* gdb.threads/multi-create-ns-info-thr.exp: New file.
When gdb creates a dummy frame to execute a function in the inferior,
the process may generate a SIGSEGV, SIGTRAP or SIGILL because the stack
is non executable. If the signal handler set in gdb has option print
or stop enabled for these signals gdb handles this correctly.
However, in the case of noprint and nostop the signal is short-circuited
and the inferior process is sent the signal directly. This causes the
inferior to crash because of gdb.
This patch adds a check for SIGSEGV, SIGTRAP or SIGILL so that these
signals are sent to gdb rather than short-circuited in the inferior.
gdb then handles them properly and the inferior process does not
crash.
This patch also fixes the same behavior in gdbserver.
Also added a small testcase to test the issue called catch-gdb-caused-signals.
This applies to Linux only, tested on Linux.
gdb/ChangeLog:
PR breakpoints/16812
* linux-nat.c (linux_nat_filter_event): Report SIGTRAP,SIGILL,SIGSEGV.
* nat/linux-ptrace.c (linux_wstatus_maybe_breakpoint): Add.
* nat/linux-ptrace.h: Add linux_wstatus_maybe_breakpoint.
gdb/gdbserver/ChangeLog:
PR breakpoints/16812
* linux-low.c (wstatus_maybe_breakpoint): Remove.
(linux_low_filter_event): Update wstatus_maybe_breakpoint name.
(linux_wait_1): Report SIGTRAP,SIGILL,SIGSEGV.
gdb/testsuite/ChangeLog:
PR breakpoints/16812
* gdb.base/catch-gdb-caused-signals.c: New file.
* gdb.base/catch-gdb-caused-signals.exp: New file.
Add a struct for identifying a processor and use it in linux-btrace.c when
identifying the processor we're running on.
We will need this feature for the new btrace format.
2015-02-09 Markus Metzger <markus.t.metzger@intel.com>
* common/btrace-common.h (btrace_cpu_vendor, btrace_cpu): New.
* nat/linux-btrace.c: (btrace_this_cpu): New.
(cpu_supports_bts): Call btrace_this_cpu.
(intel_supports_bts): Add cpu parameter.
Allow the size of the branch trace ring buffer to be defined by the
user. The specified buffer size will be used when BTS tracing is
enabled for new threads.
The obtained buffer size may differ from the requested size. The
actual buffer size for the current thread is shown in the "info record"
command.
Bigger buffers mean longer traces, but also longer processing time.
2015-02-09 Markus Metzger <markus.t.metzger@intel.com>
* btrace.c (parse_xml_btrace_conf_bts): Add size.
(btrace_conf_bts_attributes): New.
(btrace_conf_children): Add attributes.
* common/btrace-common.h (btrace_config_bts): New.
(btrace_config)<bts>: New.
(btrace_config): Update comment.
* nat/linux-btrace.c (linux_enable_btrace, linux_enable_bts):
Use config.
* features/btrace-conf.dtd: Increment version. Add size
attribute to bts element.
* record-btrace.c (set_record_btrace_bts_cmdlist,
show_record_btrace_bts_cmdlist): New.
(record_btrace_adjust_size, record_btrace_print_bts_conf,
record_btrace_print_conf, cmd_set_record_btrace_bts,
cmd_show_record_btrace_bts): New.
(record_btrace_info): Call record_btrace_print_conf.
(_initialize_record_btrace): Add commands.
* remote.c: Add PACKET_Qbtrace_conf_bts_size enum.
(remote_protocol_features): Add Qbtrace-conf:bts:size packet.
(btrace_sync_conf): Synchronize bts size.
(_initialize_remote): Add Qbtrace-conf:bts:size packet.
* NEWS: Announce new commands and new packets.
doc/
* gdb.texinfo (Branch Trace Configuration Format): Add size.
(Process Record and Replay): Describe new set|show commands.
(General Query Packets): Describe Qbtrace-conf:bts:size packet.
testsuite/
* gdb.btrace/buffer-size: New.
gdbserver/
* linux-low.c (linux_low_btrace_conf): Print size.
* server.c (handle_btrace_conf_general_set): New.
(hanle_general_set): Call handle_btrace_conf_general_set.
(handle_query): Report Qbtrace-conf:bts:size as supported.
Add a struct to describe the branch trace configuration and use it for
enabling branch tracing.
The user will be able to set configuration fields for each tracing format
to be used for new threads.
The actual configuration that is active for a given thread will be shown
in the "info record" command.
At the moment, the configuration struct only contains a format field
that is set to the only available format.
The format is the only configuration option that can not be set via set
commands. It is given as argument to the "record btrace" command when
starting recording.
2015-02-09 Markus Metzger <markus.t.metzger@intel.com>
* Makefile.in (XMLFILES): Add btrace-conf.dtd.
* x86-linux-nat.c (x86_linux_enable_btrace): Update parameters.
(x86_linux_btrace_conf): New.
(x86_linux_create_target): Initialize to_btrace_conf.
* nat/linux-btrace.c (linux_enable_btrace): Update parameters.
Check format. Split into this and ...
(linux_enable_bts): ... this.
(linux_btrace_conf): New.
(perf_event_skip_record): Renamed into ...
(perf_event_skip_bts_record): ... this. Updated users.
(linux_disable_btrace): Split into this and ...
(linux_disable_bts): ... this.
(linux_read_btrace): Check format.
* nat/linux-btrace.h (linux_enable_btrace): Update parameters.
(linux_btrace_conf): New.
(btrace_target_info)<ptid>: Moved.
(btrace_target_info)<conf>: New.
(btrace_target_info): Split into this and ...
(btrace_tinfo_bts): ... this. Updated users.
* btrace.c (btrace_enable): Update parameters.
(btrace_conf, parse_xml_btrace_conf_bts, parse_xml_btrace_conf)
(btrace_conf_children, btrace_conf_attributes)
(btrace_conf_elements): New.
* btrace.h (btrace_enable): Update parameters.
(btrace_conf, parse_xml_btrace_conf): New.
* common/btrace-common.h (btrace_config): New.
* feature/btrace-conf.dtd: New.
* record-btrace.c (record_btrace_conf): New.
(record_btrace_cmdlist): New.
(record_btrace_enable_warn, record_btrace_open): Pass
&record_btrace_conf.
(record_btrace_info): Print recording format.
(cmd_record_btrace_bts_start): New.
(cmd_record_btrace_start): Call cmd_record_btrace_bts_start.
(_initialize_record_btrace): Add "record btrace bts" subcommand.
Add "record bts" alias command.
* remote.c (remote_state)<btrace_config>: New.
(remote_btrace_reset, PACKET_qXfer_btrace_conf): New.
(remote_protocol_features): Add qXfer:btrace-conf:read.
(remote_open_1): Call remote_btrace_reset.
(remote_xfer_partial): Handle TARGET_OBJECT_BTRACE_CONF.
(btrace_target_info)<conf>: New.
(btrace_sync_conf, btrace_read_config): New.
(remote_enable_btrace): Update parameters. Call btrace_sync_conf and
btrace_read_conf.
(remote_btrace_conf): New.
(init_remote_ops): Initialize to_btrace_conf.
(_initialize_remote): Add qXfer:btrace-conf packet.
* target.c (target_enable_btrace): Update parameters.
(target_btrace_conf): New.
* target.h (target_enable_btrace): Update parameters.
(target_btrace_conf): New.
(target_object)<TARGET_OBJECT_BTRACE_CONF>: New.
(target_ops)<to_enable_btrace>: Update parameters and comment.
(target_ops)<to_btrace_conf>: New.
* target-delegates: Regenerate.
* target-debug.h (target_debug_print_const_struct_btrace_config_p)
(target_debug_print_const_struct_btrace_target_info_p): New.
NEWS: Announce new command and new packet.
doc/
* gdb.texinfo (Process Record and Replay): Describe the "record
btrace bts" command.
(General Query Packets): Describe qXfer:btrace-conf:read packet.
(Branch Trace Configuration Format): New.
gdbserver/
* linux-low.c (linux_low_enable_btrace): Update parameters.
(linux_low_btrace_conf): New.
(linux_target_ops)<to_btrace_conf>: Initialize.
* server.c (current_btrace_conf): New.
(handle_btrace_enable): Rename to ...
(handle_btrace_enable_bts): ... this. Pass ¤t_btrace_conf
to target_enable_btrace. Update comment. Update users.
(handle_qxfer_btrace_conf): New.
(qxfer_packets): Add btrace-conf entry.
(handle_query): Report qXfer:btrace-conf:read as supported packet.
* target.h (target_ops)<enable_btrace>: Update parameters and comment.
(target_ops)<read_btrace_conf>: New.
(target_enable_btrace): Update parameters.
(target_read_btrace_conf): New.
testsuite/
* gdb.btrace/delta.exp: Update "info record" output.
* gdb.btrace/enable.exp: Update "info record" output.
* gdb.btrace/finish.exp: Update "info record" output.
* gdb.btrace/instruction_history.exp: Update "info record" output.
* gdb.btrace/next.exp: Update "info record" output.
* gdb.btrace/nexti.exp: Update "info record" output.
* gdb.btrace/step.exp: Update "info record" output.
* gdb.btrace/stepi.exp: Update "info record" output.
* gdb.btrace/nohist.exp: Update "info record" output.
Collect perf event buffer related fields from btrace_target_info into
a new struct perf_event_buffer. Update functions that operated on the
buffer to take a struct perf_event_buffer pointer rather than a
btrace_target_info pointer.
2015-02-09 Markus Metzger <markus.t.metzger@intel.com>
* nat/linux-btrace.h (perf_event_buffer): New.
(btrace_target_info) <buffer, size, data_head>: Replace with ...
<bts>: ... this.
* nat/linux-btrace.c (perf_event_header, perf_event_mmap_size)
(perf_event_buffer_size, perf_event_buffer_begin)
(perf_event_buffer_end, linux_btrace_has_changed): Removed.
Updated users.
(perf_event_new_data): New.
Add a format argument to the various supports_btrace functions to check
for support of a specific btrace format. This is to prepare for a new
format.
Removed two redundant calls. The check will be made in the subsequent
btrace_enable call.
2015-02-09 Markus Metzger <markus.t.metzger@intel.com>
* btrace.c (btrace_enable): Pass BTRACE_FORMAT_BTS.
* record-btrace.c (record_btrace_open): Remove call to
target_supports_btrace.
* remote.c (remote_supports_btrace): Update parameters.
* target.c (target_supports_btrace): Update parameters.
* target.h (to_supports_btrace, target_supports_btrace): Update
parameters.
* target-delegates.c: Regenerate.
* target-debug.h (target_debug_print_enum_btrace_format): New.
* nat/linux-btrace.c
(kernel_supports_btrace): Rename into ...
(kernel_supports_bts): ... this. Update users. Update warning text.
(intel_supports_btrace): Rename into ...
(intel_supports_bts): ... this. Update users.
(cpu_supports_btrace): Rename into ...
(cpu_supports_bts): ... this. Update users.
(linux_supports_btrace): Update parameters. Split into this and ...
(linux_supports_bts): ... this.
* nat/linux-btrace.h (linux_supports_btrace): Update parameters.
gdbserver/
* server.c (handle_btrace_general_set): Remove call to
target_supports_btrace.
(supported_btrace_packets): New.
(handle_query): Call supported_btrace_packets.
* target.h: include btrace-common.h.
(btrace_target_info): Removed.
(supports_btrace, target_supports_btrace): Update parameters.
Add a structure to hold the branch trace data and an enum to describe
the format of that data. So far, only BTS is supported. Also added
a NONE format to indicate that no branch trace data is available.
This will make it easier to support different branch trace formats in
the future.
2015-02-09 Markus Metzger <markus.t.metzger@intel.com>
* Makefile.in (SFILES): Add common/btrace-common.c.
(COMMON_OBS): Add common/btrace-common.o.
(btrace-common.o): Add build rules.
* btrace.c (parse_xml_btrace): Update parameters.
(parse_xml_btrace_block): Set format field.
(btrace_add_pc, btrace_fetch): Use struct btrace_data.
(do_btrace_data_cleanup, make_cleanup_btrace_data): New.
(btrace_compute_ftrace): Split into this and...
(btrace_compute_ftrace_bts): ...this.
(btrace_stitch_trace): Split into this and...
(btrace_stitch_bts): ...this.
* btrace.h (parse_xml_btrace): Update parameters.
(make_cleanup_btrace_data): New.
* common/btrace-common.c: New.
* common/btrace-common.h: Include common-defs.h.
(btrace_block_s): Update comment.
(btrace_format): New.
(btrace_format_string): New.
(btrace_data_bts): New.
(btrace_data): New.
(btrace_data_init, btrace_data_fini, btrace_data_empty): New.
* remote.c (remote_read_btrace): Update parameters.
* target.c (target_read_btrace): Update parameters.
* target.h (target_read_btrace): Update parameters.
(target_ops)<to_read_btrace>: Update parameters.
* x86-linux-nat.c (x86_linux_read_btrace): Update parameters.
* target-delegates.c: Regenerate.
* target-debug (target_debug_print_struct_btrace_data_p): New.
* nat/linux-btrace.c (linux_read_btrace): Split into this and...
(linux_read_bts): ...this.
* nat/linux-btrace.h (linux_read_btrace): Update parameters.
gdbserver/
* Makefile.in (SFILES): Add common/btrace-common.c.
(OBS): Add common/btrace-common.o.
(btrace-common.o): Add build rules.
* linux-low: Include btrace-common.h.
(linux_low_read_btrace): Use struct btrace_data. Call
btrace_data_init and btrace_data_fini.
This commit fixes the regression on RHEL-5 systems introduced by
nat/linux-personality.c's check of HAVE_DECL_ADDR_NO_RANDOMIZE.
RHEL-5 systems define HAVE_DECL_ADDR_NO_RANDOMIZE as zero, so we
cannot use #ifndef; instead this patch uses the "#if !" construction.
The regression was reported by Ulrich Weigand here:
<https://sourceware.org/ml/gdb-patches/2015-01/msg00458.html>
gdb/ChangeLog
2015-01-16 Sergio Durigan Junior <sergiodj@redhat.com>
* nat/linux-personality.c: Replace "#ifndef
HAVE_DECL_ADDR_NO_RANDOMIZE" by "#if
!HAVE_DECL_ADDR_NO_RANDOMIZE", fixing a regression in RHEL-5
systems.
This patch moves the shared code present on
gdb/linux-nat.c:linux_nat_create_inferior and
gdb/gdbserver/linux-low.c:linux_create_inferior to
nat/linux-personality.c. This code is responsible for disabling
address space randomization based on user setting, and using
<sys/personality.h> to do that. I decided to put the prototype of the
maybe_disable_address_space_randomization on nat/linux-osdata.h
because it seemed the best place to put it.
I regression-tested this patch on Fedora 20 x86_64, and found no
regressions.
gdb/ChangeLog
2015-01-15 Sergio Durigan Junior <sergiodj@redhat.com>
* Makefile.in (HFILES_NO_SRCDIR): Add nat/linux-personality.h.
(linux-personality.o): New rule.
* common/common-defs.h: Include <stdint.h>.
* config/aarch64/linux.mh (NATDEPFILES): Include
linux-personality.o.
* config/alpha/alpha-linux.mh (NATDEPFILES): Likewise.
* config/arm/linux.mh (NATDEPFILES): Likewise.
* config/i386/linux64.mh (NATDEPFILES): Likewise.
* config/i386/linux.mh (NATDEPFILES): Likewise.
* config/ia64/linux.mh (NATDEPFILES): Likewise.
* config/m32r/linux.mh (NATDEPFILES): Likewise.
* config/m68k/linux.mh (NATDEPFILES): Likewise.
* config/mips/linux.mh (NATDEPFILES): Likewise.
* config/pa/linux.mh (NATDEPFILES): Likewise.
* config/powerpc/linux.mh (NATDEPFILES): Likewise.
* config/powerpc/ppc64-linux.mh (NATDEPFILES): Likewise.
* config/powerpc/spu-linux.mh (NATDEPFILES): Likewise.
* config/s390/linux.mh (NATDEPFILES): Likewise.
* config/sparc/linux64.mh (NATDEPFILES): Likewise.
* config/sparc/linux.mh (NATDEPFILES): Likewise.
* config/tilegx/linux.mh (NATDEPFILES): Likewise.
* config/xtensa/linux.mh (NATDEPFILES): Likewise.
* defs.h: Remove #include <stdint.h> (moved to
common/common-defs.h).
* linux-nat.c: Include nat/linux-personality.h. Remove #include
<sys/personality.h>; do not define ADDR_NO_RANDOMIZE (moved to
nat/linux-personality.c).
(linux_nat_create_inferior): Remove code to disable address space
randomization (moved to nat/linux-personality.c). Create cleanup
to disable address space randomization.
* nat/linux-personality.c: New file.
* nat/linux-personality.h: Likewise.
gdb/gdbserver/ChangeLog
2015-01-15 Sergio Durigan Junior <sergiodj@redhat.com>
* Makefile.in (SFILES): Add linux-personality.c.
(linux-personality.o): New rule.
* configure.srv (srv_linux_obj): Add linux-personality.o to the
list of objects to be built.
* linux-low.c: Include nat/linux-personality.h.
(linux_create_inferior): Remove code to disable address space
randomization (moved to ../nat/linux-personality.c). Create
cleanup to disable address space randomization.
This patch is to teach both GDB and GDBServer to detect 64-bit inferior
correctly. We find a problem that GDBServer is unable to detect on a
e5500 core processor. Current GDBServer assumes that MSR is a 64-bit
register, but MSR is a 32-bit register in Book III-E. This patch is
to fix this problem by checking the right bit in MSR, in order to handle
both Book III-S and Book III-E. In order to detect Book III-S and
Book III-E, we check the PPC_FEATURE_BOOKE from the host's HWCAP (by
getauxval on glibc >= 2.16. If getauxval doesn't exist, we implement
the fallback by parsing /proc/self/auxv), because it should an invariant
on the same machine cross different processes.
In order to share code, I add nat/ppc-linux.c for both GDB and
GDBserver side.
gdb:
2015-01-14 Yao Qi <yao@codesourcery.com>
* Makefile.in (ppc-linux.o): New rule.
* config/powerpc/ppc64-linux.mh (NATDEPFILES): Add ppc-linux.o.
* configure.ac: AC_CHECK_FUNCS(getauxval).
* config.in: Re-generated.
* configure: Re-generated.
* nat/ppc-linux.h [__powerpc64__] (ppc64_64bit_inferior_p):
Declare.
* nat/ppc-linux.c: New file.
* ppc-linux-nat.c (ppc_linux_target_wordsize) [__powerpc64__]:
Call ppc64_64bit_inferior_p.
gdb/gdbserver:
2015-01-14 Yao Qi <yao@codesourcery.com>
* Makefile.in (SFILES): Add nat/ppc-linux.c.
(ppc-linux.o): New rule.
* configure.srv (powerpc*-*-linux*): Add ppc-linux.o.
* configure.ac: AC_CHECK_FUNCS(getauxval).
* config.in: Re-generated.
* configure: Re-generated.
* linux-ppc-low.c (ppc_arch_setup) [__powerpc64__]: Call
ppc64_64bit_inferior_p
When I use PPC_FEATURE_BOOKE in GDBserver, I find it is defined in GDB
but not in GDBserver. After taking a further look, I find some macros
are duplicated between ppc-linux-nat.c and linux-ppc-low.c, so this
patch is to move them into nat/ppc-linux.h.
gdb/gdbserver:
2015-01-14 Yao Qi <yao@codesourcery.com>
* linux-ppc-low.c: Include "nat/ppc-linux.h".
(PPC_FEATURE_HAS_VSX): Move to nat/ppc-linux.h.
(PPC_FEATURE_HAS_ALTIVEC, PPC_FEATURE_HAS_SPE): Likewise.
(PT_ORIG_R3, PT_TRAP): Likewise.
(PTRACE_GETVSXREGS, PTRACE_SETVSXREGS): Likewise.
(PTRACE_GETVRREGS, PTRACE_SETVRREGS): Likewise.
(PTRACE_GETEVRREGS, PTRACE_SETEVRREGS): Likewise.
gdb:
2015-01-14 Yao Qi <yao@codesourcery.com>
* ppc-linux-nat.c (PT_ORIG_R3, PT_TRAP): Move to
nat/ppc-linux.h.
(PPC_FEATURE_CELL, PPC_FEATURE_BOOKE): Likewise.
(PPC_FEATURE_HAS_DFP): Likewise.
(PTRACE_GETVRREGS, PTRACE_SETVRREGS): Likewise.
(PTRACE_GETVSXREGS, PTRACE_SETVSXREGS): Likewise.
(PTRACE_GETEVRREGS, PTRACE_SETEVRREGS): Likewise.
Include "nat/ppc-linux.h".
* nat/ppc-linux.h: New file.
* Makefile.in (HFILES_NO_SRCDIR): Add nat/ppc-linux.h.
... instead of relying on libthread_db.
I wrote a test that attaches to a program that constantly spawns
short-lived threads, which exposed several issues. This is one of
them.
On Linux, we need to attach to all threads of a process (thread group)
individually. We currently rely on libthread_db to list the threads,
but that is problematic, because libthread_db relies on reading data
structures out of the inferior (which may well be corrupted). If
threads are being created or exiting just while we try to attach, we
may trip on inconsistencies in the inferior's thread list. To work
around that, when we see a seemingly corrupt list, we currently retry
a few times:
static void
thread_db_find_new_threads_2 (ptid_t ptid, int until_no_new)
{
...
if (until_no_new)
{
/* Require 4 successive iterations which do not find any new threads.
The 4 is a heuristic: there is an inherent race here, and I have
seen that 2 iterations in a row are not always sufficient to
"capture" all threads. */
...
That heuristic may well fail, and when it does, we end up with threads
in the program that aren't under GDB's control. That's obviously bad
and results in quite mistifying failures, like e.g., the process dying
for seeminly no reason when a thread that wasn't attached trips on a
breakpoint.
There's really no reason to rely on libthread_db for this nowadays
when we have /proc mounted. In that case, which is the usual case, we
can list the LWPs from /proc/PID/task/. In fact, GDBserver is already
doing this. The patch factors out that code that knows to walk the
task/ directory out of GDBserver, and makes GDB use it too.
Like GDBserver, the patch makes GDB attach to LWPs and _not_ wait for
them to stop immediately. Instead, we just tag the LWP as having an
expected stop. Because we can only set the ptrace options when the
thread stops, we need a new flag in the lwp structure to keep track of
whether we've already set the ptrace options, just like in GDBserver.
Note that nothing issues any ptrace command to the threads between the
PTRACE_ATTACH and the stop, so this is safe (unlike one scenario
described in gdbserver's linux-low.c).
When we attach to a program that has threads exiting while we attach,
it's easy to race with a thread just exiting as we try to attach to
it, like:
#1 - get current list of threads
#2 - attach to each listed thread
#3 - ooops, attach failed, thread is already gone
As this is pretty normal, we shouldn't be issuing a scary warning in
step #3.
When #3 happens, PTRACE_ATTACH usually fails with ESRCH, but sometimes
we'll see EPERM as well. That happens when the kernel still has the
thread in its task list, but the thread is marked as dead.
Unfortunately, EPERM is ambiguous and we'll get it also on other
scenarios where the thread isn't dead, and in those cases, it's useful
to get a warning. To distiguish the cases, when we get an EPERM
failure, we open /proc/PID/status, and check the thread's state -- if
the /proc file no longer exists, or the state is "Z (Zombie)" or "X
(Dead)", we ignore the EPERM error silently; otherwise, we'll warn.
Unfortunately, there seems to be a kernel race here. Sometimes I get
EPERM, and then the /proc state still indicates "R (Running)"... If
we wait a bit and retry, we do end up seeing X or Z state, or get an
ESRCH. I thought of making GDB retry the attach a few times, but even
with a 500ms wait and 4 retries, I still see the warning sometimes. I
haven't been able to identify the kernel path that causes this yet,
but in any case, it looks like a kernel bug to me. As this just
results failure to suppress a warning that we've been printing since
about forever anyway, I'm just making the test cope with it, and issue
an XFAIL.
gdb/gdbserver/
2015-01-09 Pedro Alves <palves@redhat.com>
* linux-low.c (linux_attach_fail_reason_string): Move to
nat/linux-ptrace.c, and rename.
(linux_attach_lwp): Update comment.
(attach_proc_task_lwp_callback): New function.
(linux_attach): Adjust to rename and use
linux_proc_attach_tgid_threads.
(linux_attach_fail_reason_string): Delete declaration.
gdb/
2015-01-09 Pedro Alves <palves@redhat.com>
* linux-nat.c (attach_proc_task_lwp_callback): New function.
(linux_nat_attach): Use linux_proc_attach_tgid_threads.
(wait_lwp, linux_nat_filter_event): If not set yet, set the lwp's
ptrace option flags.
* linux-nat.h (struct lwp_info) <must_set_ptrace_flags>: New
field.
* nat/linux-procfs.c: Include <dirent.h>.
(linux_proc_get_int): New parameter "warn". Handle it.
(linux_proc_get_tgid): Adjust.
(linux_proc_get_tracerpid): Rename to ...
(linux_proc_get_tracerpid_nowarn): ... this.
(linux_proc_pid_get_state): New function, factored out from
(linux_proc_pid_has_state): ... this. Add new parameter "warn"
and handle it.
(linux_proc_pid_is_gone): New function.
(linux_proc_pid_is_stopped): Adjust.
(linux_proc_pid_is_zombie_maybe_warn)
(linux_proc_pid_is_zombie_nowarn): New functions.
(linux_proc_pid_is_zombie): Use
linux_proc_pid_is_zombie_maybe_warn.
(linux_proc_attach_tgid_threads): New function.
* nat/linux-procfs.h (linux_proc_get_tgid): Update comment.
(linux_proc_get_tracerpid): Rename to ...
(linux_proc_get_tracerpid_nowarn): ... this, and update comment.
(linux_proc_pid_is_gone): New declaration.
(linux_proc_pid_is_zombie): Update comment.
(linux_proc_pid_is_zombie_nowarn): New declaration.
(linux_proc_attach_lwp_func): New typedef.
(linux_proc_attach_tgid_threads): New declaration.
* nat/linux-ptrace.c (linux_ptrace_attach_fail_reason): Adjust to
use nowarn functions.
(linux_ptrace_attach_fail_reason_string): Move here from
gdbserver/linux-low.c and rename.
(ptrace_supports_feature): If the current ptrace options are not
known yet, check them now, instead of asserting.
* nat/linux-ptrace.h (linux_ptrace_attach_fail_reason_string):
Declare.
Andreas Arnez
Adhemerval Zanella
Pedro Alves
Andrew Pinski
Gary Benson
Walfred Tedeschi
Yao Qi
Joel Brobecker
Simon Marchi
Doug Evans
Simon Marchi
Don Breazeal
Markus Metzger
Ulrich Weigand
Jan Kratochvil
Peter Bergner
Michael Eager
Antoine Tremblay
Sergio Durigan Junior
Yao Qi