When calling function with argument of size more than 8 bytes fails with
an error "That operation is not available on integers of more than 8 bytes.".
avr-gdb considers only 8 bytes (sizeof(long long)) in case of passing the
argument in registers. When the argument is of size more than 8 byte
then the utility function to extract bytes failed with the above error.
gdb/
* avr-tdep.c (AVR_LAST_ARG_REGNUM): Define.
(avr_push_dummy_call): Correct last needed argument register.
Write MSB of argument into register and subsequent bytes into
other registers in decreasing order.
ARM process record gets the wrong register number for VMOV (from core
register to single-precision register). That is, we should record
the D register rather than the S pseudo register. The patch also
removes the condition "bit (arm_insn_r->arm_insn, 20)" check, which
has been checked above.
It fixes the following internal error,
(gdb) PASS: gdb.reverse/finish-precsave.exp: BP at end of main
continue^M
Continuing.^M
../../binutils-gdb/gdb/regcache.c:649: internal-error: regcache_raw_read: Assertion `regnum >= 0 && regnum < regcache->descr->nr_raw_registers' failed.^M
A problem internal to GDB has been detected,FAIL: gdb.reverse/finish-precsave.exp: run to end of main (GDB internal error)
gdb:
2016-03-04 Yao Qi <yao.qi@linaro.org>
* arm-tdep.c (arm_record_vdata_transfer_insn): Simplify the
condition check. Record the right D register number.
This patch removes the printing "Process record does not support",
and do the print by calling arm_record_unsupported_insn in the
caller. Also, call arm_record_extension_space only when condition
is 0xf.
gdb:
2016-03-04 Yao Qi <yao.qi@linaro.org>
* arm-tdep.c (arm_record_extension_space): Remove code
printing "Process record does not support".
(arm_record_data_proc_misc_ld_str): Likewise.
(decode_insn): Call arm_record_extension_space if condition
is 0xf. Call arm_record_unsupported_insn if ret isn't
ARM_RECORD_SUCCESS. Use 'ret' instead of 'insn_id' to hold
the value of thumb2_record_decode_insn_handler.
I found that odd that passing no arguments to feature_to_c.sh produces
this:
$ ./feature_to_c.sh
./feature_to_c.sh: 23: shift: can't shift that many
but passing one argument shows the help:
$ ./feature_to_c.sh hello
Usage: ./feature_to_c.sh OUTPUTFILE INPUTFILE...
This patch changes the script to show the help in both cases.
gdb/ChangeLog:
* features/feature_to_c.sh: Print the help when passing no
argument.
Add new maintainer to Write After Approval.
2016-03-02 Bernhard Heckel <bernhard.heckel@intel.com>
* MAINTAINERS (Write After Approval): Add Bernhard Heckel.
This fixes a GDB internal error that may occur when the inferior has no
valid stack pointer in r15.
gdb/testsuite/ChangeLog:
* gdb.arch/s390-stackless.S: New.
* gdb.arch/s390-stackless.exp: New.
gdb/ChangeLog:
* s390-linux-tdep.c (s390_backchain_frame_unwind_cache): Avoid
exception when attempting to access the inferior's backchain.
The last patch supports several syscalls in linux-record.c, so now
GDB aarch64-linux backend can return these canonicalized syscall numbers
per aarch64 syscall number.
This patch fixes the following fails,
Process record and replay target doesn't support syscall number 59^M
Process record: failed to record execution log.^M
^M
Program stopped.^M
0x00000020000eab28 in pipe () from /lib/aarch64-linux-gnu/libc.so.6^M
(gdb) FAIL: gdb.reverse/pipe-reverse.exp: continue to breakpoint: marker2
Process record and replay target doesn't support syscall number 59^M
Process record: failed to record execution log.^M
^M
Program stopped.^M
0x00000020000eab28 in pipe () from /lib/aarch64-linux-gnu/libc.so.6^M
(gdb) FAIL: gdb.reverse/readv-reverse.exp: continue to breakpoint: marker2
gdb:
2016-02-29 Yao Qi <yao.qi@linaro.org>
* aarch64-linux-tdep.c (aarch64_canonicalize_syscall): Support
eventfd2, eventfd2, dup3, inotify_init1, fallocate and pipe2.
Return gdb_sys_epoll_create1 instead of gdb_sys_epoll_create
for aarch64_sys_epoll_create1.
Given two or more modules that import each other's scope, the current symbol
lookup routines would go round in circles looking through each import from
each module, possibly checking the same module twice or more until all possible
paths are marked as "searched".
Given enough modules, this causes an exponential slowdown in time taken to find
symbols that do exist, and infinite recursion when they don't.
gdb/ChangeLog:
* d-namespace.c (d_lookup_symbol_imports): Avoid recursive lookups from
cyclic imports.
gdb/testsuite/ChangeLog:
* gdb.dlang/circular.c: New file.
* gdb.dlang/circular.exp: New file.
This is an obvious patch to fix the following build error seen with
--enable-build-with-cxx:
../../src/gdb/rs6000-tdep.c: In function ‘rs6000_frame_cache* rs6000_frame_cache(frame_info*, void**)’:
../../src/gdb/rs6000-tdep.c:3242:15: error: invalid conversion from ‘void*’ to ‘rs6000_frame_cache*’ [-fpermissive]
return (*this_cache);
~^~~~~~~~~~~~
gdb/ChangeLog
* rs6000-tdep.c (rs6000_frame_cache): Explicitly cast return result
to avoid invalid conversion from void *.
This patch fixes various bugs in arm_record_exreg_ld_st_insn, and use
gdb.reverse/insn-reverse.c to test more arm instructions.
- Set flag SINGLE_REG correctly. In the arch reference manual,
SING_REG is true when the bit 8 of instruction is zero.
- Record the right D registers for instructions changing S registers.
- Fix the order of length and address in record_buf_mem array.
- Shift the offset by 2 instead of by 24.
This patch also fixes one internal error,
(gdb) PASS: gdb.reverse/finish-precsave.exp: BP at end of main
continue^M
Continuing.^M
../../binutils-gdb/gdb/utils.c:1072: internal-error: virtual memory exhausted.^M
A problem internal to GDB has been detected,FAIL: gdb.reverse/finish-precsave.exp: run to end of main (GDB internal error)
gdb:
2016-02-26 Yao Qi <yao.qi@linaro.org>
* arm-tdep.c (arm_record_exreg_ld_st_insn): Set 'single_reg'
per bit 8. Check bit 20 instead of bit 4 for VMOV
instruction. Record D registers for instructions changing
S registers. Change of the order of length and address
in record_buf_mem array.
gdb/testsuite:
2016-02-26 Yao Qi <yao.qi@linaro.org>
* gdb.reverse/insn-reverse.c [__arm__] (ext_reg_load): New.
[__arm__] (ext_reg_mov, ext_reg_push_pop): New.
(testcases): Update.
When GDB decodes these thumb special data instructions, such as 'mov sp, r7'
the Rd is got incorrectly. According to the arch reference manual, the Rd
is DN:Rdn, in which DN is bit 7 and Rdn is bits 0 to 2. This patch fixes it.
gdb:
2016-02-26 Yao Qi <yao.qi@linaro.org>
* arm-tdep.c (thumb_record_ld_st_reg_offset): Fix the register
number of Rd.
We see this error when building with gcc 4.3.
../../gdb/i386-linux-tdep.c: In function ‘i386_linux_handle_segmentation_fault’:
../../gdb/i386-linux-tdep.c:399: error: ‘access’ may be used uninitialized in this function
../../gdb/i386-linux-tdep.c:399: error: ‘upper_bound’ may be used uninitialized in this function
../../gdb/i386-linux-tdep.c:399: error: ‘lower_bound’ may be used uninitialized in this function
It's a false positive, since the variables will always get initialized
in the TRY clause, and the CATCH returns.
gdb/ChangeLog:
* i386-linux-tdep.c (i386_linux_handle_segmentation_fault):
Initialize variables.
When encoding the agent expression operation ax_reg or ax_reg_mask, the
register number used is internal to GDB. However GDBServer expects a tdesc
based number.
This usually does not cause a problem since at the moment, for raw
registers GDBServer R trace action ignores the register mask and just
collects all registers.
It can be a problem, however with pseudo registers on some platforms if the
tdesc number doesn't match the GDB internal register number.
This is the case with ARM, the upcoming ARM tracepoint support, fails
these test cases without this patch:
gdb.trace/collection.exp: collect register locals collectively:*
GDBSever would exit with: unhandled register size
Since the register number is not mapped.
This patch fixes these issues by calling gdbarch_remote_register_number
before encoding the register number in the ax_reg or ax_reg_mask operation.
Tested on x86 native-gdbserver no regressions observed.
gdb/ChangeLog:
* ax-general.c (ax_reg): Call gdbarch_remote_register_number.
(ax_reg_mask): Likewise.
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.
This commit fixes an error in exec_file_locate_attach where
the main executable could be loaded from outside the sysroot
if a nonempty, non-"target:" sysroot was set but the discovered
executable filename did not exist in that sysroot and did exist
on the main filesystem.
gdb/ChangeLog:
* exec.c (exec_file_locate_attach): Do not attempt to
locate main executable locally if not found in sysroot.
gdb/testsuite/ChangeLog:
* gdb.base/attach-pie-noexec.exp: Do not expect an error
message on attach.
gdb/ChangeLog:
Extend "skip" command to support -file, -gfile, -function, -rfunction.
* NEWS: Document new features.
* skip.c: #include "fnmatch.h", "gdb_regex.h".
(skiplist_entry) <file>: Renamed from filename.
<function>: Renamed from function_name.
<file_is_glob, function_is_regexp>: New members.
<compiled_function_regexp, compiled_function_regexp_is_valid>:
New members.
(make_skip_entry): New function.
(free_skiplist_entry, free_skiplist_entry_cleanup): New functions.
(make_free_skiplist_entry_cleanup): New function.
(skip_file_command): Update.
(skip_function, skip_function_command): Update.
(compile_skip_regexp): New functions.
(skip_command): Add support for new options.
(skip_info): Update.
(skip_file_p, skip_gfile_p): New functions.
(skip_function_p, skip_rfunction_p): New functions.
(function_name_is_marked_for_skip): Update and simplify.
(_initialize_step_skip): Update.
* symtab.c: #include "fnmatch.h".
(compare_glob_filenames_for_search): New function.
* symtab.h (compare_glob_filenames_for_search): Declare.
* utils.c (count_path_elements): New function.
(strip_leading_path_elements): New function.
* utils.h (count_path_elements): Declare.
(strip_leading_path_elements): Declare.
gdb/doc/ChangeLog:
* gdb.texinfo (Skipping Over Functions and Files): Document new
options to "skip" command. Update docs of output of "info skip".
gdb/testsuite/ChangeLog:
* gdb.base/skip.c (test_skip): New function.
(end_test_skip_file_and_function): New function.
(test_skip_file_and_function): New function.
* gdb.base/skip1.c (test_skip): New function.
(skip1_test_skip_file_and_function): New function.
* gdb.base/skip.exp: Add tests for new skip options.
* gdb.base/skip-solib.exp: Update expected output.
* gdb.perf/skip-command.cc: New file.
* gdb.perf/skip-command.exp: New file.
* gdb.perf/skip-command.py: New file.
This patch updates the syscalls in sync with syscalls/aarch64-linux.xml.
Some syscalls are still not supported by gdb/linux-record.c yet. Mark
them UNSUPPORTED_SYSCALL_MAP.
This patch fixes the following test fail,
Process record and replay target doesn't support syscall number 56^M
Process record: failed to record execution log.^M
^M
Program stopped.^M
0x00000020000e9dfc in open () from /lib/aarch64-linux-gnu/libc.so.6^M
(gdb) FAIL: gdb.reverse/fstatat-reverse.exp: continue to breakpoint: marker2
gdb:
2016-02-23 Yao Qi <yao.qi@linaro.org>
* aarch64-linux-tdep.c (enum aarch64_syscall) <aarch64_sys_mknod>:
Remove.
<aarch64_sys_mkdir, aarch64_sys_unlink, aarch64_sys_symlink>: Remove.
<aarch64_sys_link, aarch64_sys_rename, aarch64_sys_faccess>: Remove.
<aarch64_sys_mknodat, aarch64_sys_mkdirat>: New.
<aarch64_sys_unlinkat, aarch64_sys_symlinkat>: New.
<aarch64_sys_linkat, aarch64_sys_renameat, aarch64_sys_faccessat>: New.
<aarch64_sys_open, aarch64_sys_readlink, aarch64_sys_fstatat>: Remove.
<aarch64_sys_openat, aarch64_sys_readlinkat>: New.
<aarch64_sys_newfstatat>: New.
(UNSUPPORTED_SYSCALL_MAP): New macro.
(aarch64_canonicalize_syscall): Add missing syscalls.
After building GDB
--with-python=/usr/bin/python3
and for example stripping ./gdb and running:
./gdb -data-directory data-directory/ -iex "add-auto-load-safe-path $PWD/gdb-gdb.gdb" -iex "add-auto-load-safe-path $PWD/gdb-gdb.
py" ./gdb
I get:
Make breakpoint pending on future shared library load? (y or [n]) [answered N; input not from terminal]
File "/home/jkratoch/redhat/gdb-test-python3/gdb/gdb-gdb.py", line 91
print "Warning: Cannot find enum type_flag_value type."
^
SyntaxError: Missing parentheses in call to 'print'
(top-gdb) q
gdb/ChangeLog
2016-02-22 Jan Kratochvil <jan.kratochvil@redhat.com>
* gdb-gdb.py (class TypeFlagsPrinter): Use parentheses for print.
This patch fixes the various code format issues in arm process record
in arm-tdep.c, such as using tab instead of spaces.
gdb:
2016-02-22 Yao Qi <yao.qi@linaro.org>
* arm-tdep.c: Fix code format issues.
With Intel Memory Protection Extensions it was introduced the concept of
boundary violation. A boundary violations is presented to the inferior as
a segmentation fault having SIGCODE 3. This patch adds a
handler for a boundary violation extending the information displayed
when a bound violation is presented to the inferior. In the stop mode
case the debugger will also display the kind of violation: "upper" or
"lower", bounds and the address accessed.
On no stop mode the information will still remain unchanged. Additional
information about bound violations are not meaningful in that case user
does not know the line in which violation occurred as well.
When the segmentation fault handler is stop mode the out puts will be
changed as exemplified below.
The usual output of a segfault is:
Program received signal SIGSEGV, Segmentation fault
0x0000000000400d7c in upper (p=0x603010, a=0x603030, b=0x603050,
c=0x603070, d=0x603090, len=7) at i386-mpx-sigsegv.c:68
68 value = *(p + len);
In case it is a bound violation it will be presented as:
Program received signal SIGSEGV, Segmentation fault
Upper bound violation while accessing address 0x7fffffffc3b3
Bounds: [lower = 0x7fffffffc390, upper = 0x7fffffffc3a3]
0x0000000000400d7c in upper (p=0x603010, a=0x603030, b=0x603050,
c=0x603070, d=0x603090, len=7) at i386-mpx-sigsegv.c:68
68 value = *(p + len);
In mi mode the output of a segfault is:
*stopped,reason="signal-received",signal-name="SIGSEGV",
signal-meaning="Segmentation fault", frame={addr="0x0000000000400d7c",
func="upper",args=[{name="p", value="0x603010"},{name="a",value="0x603030"}
,{name="b",value="0x603050"}, {name="c",value="0x603070"},
{name="d",value="0x603090"},{name="len",value="7"}],
file="i386-mpx-sigsegv.c",fullname="i386-mpx-sigsegv.c",line="68"},
thread-id="1",stopped-threads="all",core="6"
in the case of a bound violation:
*stopped,reason="signal-received",signal-name="SIGSEGV",
signal-meaning="Segmentation fault",
sigcode-meaning="Upper bound violation",
lower-bound="0x603010",upper-bound="0x603023",bound-access="0x60302f",
frame={addr="0x0000000000400d7c",func="upper",args=[{name="p",
value="0x603010"},{name="a",value="0x603030"},{name="b",value="0x603050"},
{name="c",value="0x603070"},{name="d",value="0x603090"},
{name="len",value="7"}],file="i386-mpx-sigsegv.c",
fullname="i386-mpx-sigsegv.c",line="68"},thread-id="1",
stopped-threads="all",core="6"
2016-02-18 Walfred Tedeschi <walfred.tedeschi@intel.com>
gdb/ChangeLog:
* NEWS: Add entry for bound violation.
* amd64-linux-tdep.c (amd64_linux_init_abi_common):
Add handler for segmentation fault.
* gdbarch.sh (handle_segmentation_fault): New.
* gdbarch.c: Regenerate.
* gdbarch.h: Regenerate.
* i386-linux-tdep.c (i386_linux_handle_segmentation_fault): New.
(SIG_CODE_BONDARY_FAULT): New define.
(i386_linux_init_abi): Use i386_mpx_bound_violation_handler.
* i386-linux-tdep.h (i386_linux_handle_segmentation_fault) New.
* i386-tdep.c (i386_mpx_enabled): Add as external.
* i386-tdep.c (i386_mpx_enabled): Add as external.
* infrun.c (handle_segmentation_fault): New function.
(print_signal_received_reason): Use handle_segmentation_fault.
gdb/testsuite/ChangeLog:
* gdb.arch/i386-mpx-sigsegv.c: New file.
* gdb.arch/i386-mpx-sigsegv.exp: New file.
* gdb.arch/i386-mpx-simple_segv.c: New file.
* gdb.arch/i386-mpx-simple_segv.exp: New file.
gdb/doc/ChangeLog:
* gdb.texinfo (Signals): Add bound violation display hints for
a SIGSEGV.
When we're looking at a tracefile trace frame where registers are not
available, and the tracepoint has only one location, we supply
the location's address as the PC register. However, this only works
if PC is not a pseudo register, and individual architectures may want
to guess more registers. Add a gdbarch hook that will handle that.
gdb/ChangeLog:
* arch-utils.c (default_guess_tracepoint_registers): New function.
* arch-utils.h (default_guess_tracepoint_registers): New prototype.
* gdbarch.c: Regenerate.
* gdbarch.h: Regenerate.
* gdbarch.sh: Add guess_tracepoint_registers hook.
* tracefile.c (tracefile_fetch_registers): Use the new gdbarch hook.
exec_file_locate_attach allocates memory for full_exec_path (using
either exec_file_find, source_full_path_of or xstrdup) but this
memory is never freed. This commit adds the necessary cleanup.
gdb/ChangeLog:
* exec.c (exec_file_locate_attach): Add missing cleanup.
This patch fixes an internal error that occurs in
gdb.threads/forking-threads-plus-breakpoint.exp:
/blah/binutils-gdb/gdb/target.c:2723: internal-error: Can't determine the
current address space of thread Thread 3170.3170
In default_thread_address_space, find_inferior_ptid couldn't find 3170.3170
because it had been overwritten in inferior_appeared, called as follows:
inferior_appeared
remote_add_inferior
remote_notice_new_inferior
remote_update_thread_list
The cause of the problem was the following sequence of events:
* GDB knows only about the main thread
* the first fork event is reported to GDB, saved as pending_event
* qXfer:threads:read gets the threads from the remote.
remove_new_fork_children id's the fork child from the pending event
and removes it from the list reported to GDB. All the rest of the
threads, including the fork parent, are added to the GDB thread list.
* GDB stops all the threads. All the stop events are pushed onto the
stop reply queue behind the pending fork event. The fork waitstatus
is saved in the fork parent thread's pending status field
thread_info.suspend.
* remote_wait_ns calls queued_stop_reply and process_stop_reply to
remove the fork event from the front of the stop reply queue and save
event information in the thread_info structure for the fork parent
thread. Unfortunately, none of the information saved in this way is
the fork-specific information.
* A subsequent qXfer:threads:read packet gets the thread list including
the fork parent and fork child. remove_new_fork_children checks the
thread list to see if there is a fork parent, doesn't find one, checks
the stop reply queue for a pending fork event, doesn't find one, and
allows the fork child thread to be reported to GDB before the fork
event has been handled. remote_update_thread_list calls
remote_notice_new_thread and overwrites the current (main) thread in
inferior_appeared.
So the fork event has been reported out of target_wait but it was left
pending on the infrun side (infrun.c:save_waitstatus). IOW, the fork
event hasn't been processed by handle_inferior_event yet, so it hasn't
made it to tp->pending_follow yet.
The fix is to check thread_info.suspend along with the
thread_info.pending_follow in remote.c:remove_new_fork_children, to
prevent premature reporting of the fork child thread creation.
gdb/ChangeLog:
PR remote/19496
* remote.c (remove_new_fork_children): Check for pending
fork status in thread_info.suspend.
gdb/testsuite/ChangeLog:
PR remote/19496
* gdb.threads/forking-threads-plus-breakpoint.exp (do_test):
Remove kfail for PR remote/19496.
I see the following error in testing aarch64 GDB debugging arm
program.
(gdb) PASS: gdb.reverse/readv-reverse.exp: set breakpoint at marker2
continue
Continuing.
=================================================================
==32273==ERROR: AddressSanitizer: attempting free on address which was not malloc()-ed: 0x000000ce4c00 in thread T0
#0 0x2ba5615645c7 in __interceptor_free (/usr/lib/x86_64-linux-gnu/libasan.so.1+0x545c7)^M
#1 0x4be8b5 in VEC_CORE_ADDR_cleanup /home/yao/SourceCode/gnu/gdb/git/gdb/common/gdb_vecs.h:34^M
#2 0x5e6d95 in do_my_cleanups /home/yao/SourceCode/gnu/gdb/git/gdb/common/cleanups.c:154^M
#3 0x64c99a in fetch_inferior_event /home/yao/SourceCode/gnu/gdb/git/gdb/infrun.c:3975^M
#4 0x678437 in inferior_event_handler /home/yao/SourceCode/gnu/gdb/git/gdb/inf-loop.c:44^M
#5 0x5078f6 in remote_async_serial_handler /home/yao/SourceCode/gnu/gdb/git/gdb/remote.c:13223^M
#6 0x4cecfd in run_async_handler_and_reschedule /home/yao/SourceCode/gnu/gdb/git/gdb/ser-base.c:137^M
#7 0x676864 in gdb_wait_for_event /home/yao/SourceCode/gnu/gdb/git/gdb/event-loop.c:834^M
#8 0x676a27 in gdb_do_one_event /home/yao/SourceCode/gnu/gdb/git/gdb/event-loop.c:323^M
#9 0x676aed in start_event_loop /home/yao/SourceCode/gnu/gdb/git/gdb/event-loop.c:347^M
#10 0x6706d2 in captured_command_loop /home/yao/SourceCode/gnu/gdb/git/gdb/main.c:318^M
#11 0x66db8c in catch_errors /home/yao/SourceCode/gnu/gdb/git/gdb/exceptions.c:240^M
#12 0x6716dd in captured_main /home/yao/SourceCode/gnu/gdb/git/gdb/main.c:1157^M
#13 0x66db8c in catch_errors /home/yao/SourceCode/gnu/gdb/git/gdb/exceptions.c:240^M
#14 0x671b7a in gdb_main /home/yao/SourceCode/gnu/gdb/git/gdb/main.c:1165^M
#15 0x467684 in main /home/yao/SourceCode/gnu/gdb/git/gdb/gdb.c:32^M
#16 0x2ba563ed7ec4 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x21ec4)^M
#17 0x4676b2 (/scratch/yao/gdb/build-git/aarch64-linux-gnu/gdb/gdb+0x4676b2)
looks we should discard cleanup if function
arm_linux_software_single_step returns early, or create cleanup when
it is needed.
gdb:
2016-02-16 Yao Qi <yao.qi@linaro.org>
* arm-linux-tdep.c (arm_linux_software_single_step): Assign
'old_chain' later.
Method syscall_next_pc of struct arm_get_next_pcs_ops has an argument
PC, which is not necessary, because PC can be got from regcache in
'struct arm_get_next_pcs'. This patch removes the PC argument of
syscall_next_pc.
gdb:
2016-02-16 Yao Qi <yao.qi@linaro.org>
* arch/arm-get-next-pcs.h (struct arm_get_next_pcs_ops)
<syscall_next_pc>: Remove argument PC. Callers updated.
* arm-linux-tdep.c (arm_linux_get_next_pcs_syscall_next_pc):
Remove argument PC. Get pc from regcache_read_pc.
* arm-tdep.c (arm_get_next_pcs_syscall_next_pc): Remove
argument PC.
gdb/gdbserver:
2016-02-16 Yao Qi <yao.qi@linaro.org>
* linux-arm-low.c (get_next_pcs_syscall_next_pc): Remove argument
PC. Get pc from regcache_read_pc.
core_addr_to_string_nz returns string which has "0x" prefix, so don't
need to print "0x" again. This patch is to remove the "0x".
gdb:
2016-02-15 Yao Qi <yao.qi@linaro.org>
* aarch64-tdep.c (aarch64_analyze_prologue): Remove "0x".
GDB step cross kernel helpers only works if the kernel helpers are tail
called, which is the case how it is used in glibc. See __aeabi_read_tp
in sysdeps/unix/sysv/linux/arm/aeabi_read_tp.S. In __aeabi_read_tp,
branch/jump to the kernel helper is the last instruction, and the next
instruction address is in LR, which is in caller function. GDB can
handle this correctly. For example, glibc function __GI___ctype_init
calls __aeabi_read_tp
0xb6e19b30 <__GI___ctype_init+4>: ldr r3, [pc, #80] ;
0xb6e19b34 <__GI___ctype_init+8>: bl 0xb6e0a6e0 <__aeabi_read_tp>
0xb6e19b38 <__GI___ctype_init+12>: ldr r3, [pc, r3]
and __aeabi_read_tp calls kernel helper,
(gdb) disassemble __aeabi_read_tp
0xb6fef5d0 <+0>: mvn r0, #61440 ; 0xf000
0xb6fef5d4 <+4>: sub pc, r0, #31
once GDB or GDBserver single step instruction on 0xb6fef5d4, LR is
0xb6e19b38, which is right address of next instruction to set breakpoint
on.
However, if the kernel helpers are not tail-called, the LR is still the
address in the caller function of kernel helper's caller, which isn't
the right address of next instruction to set breakpoint on. For example,
we use kernel helper in main,
(gdb) disassemble main
....
0x00008624 <+32>: mov r3, #4064 ; 0xfe0^M
0x00008628 <+36>: movt r3, #65535 ; 0xffff^M
0x0000862c <+40>: blx r3
0x00008630 <+44>: ldr r3, [r11, #-8]
kernel helper is called on 0x0000862c and the expected next instruction
address is 0x00008630, but the LR now is the return address of main.
The problem here is LR may not have the right address because when we
single step the instruction, it isn't executed yet, so the LR isn't
updated. This patch fix this problem by decoding instruction, if the
instruction updates LR (BL and BLX), the next instruction address is
PC + INSN_SIZE, otherwise, get the address of next instruction from LR.
gdb:
2016-02-12 Yao Qi <yao.qi@linaro.org>
* arch/arm-linux.c (arm_linux_get_next_pcs_fixup): Calculate
nextpc according to instruction.
gdb/testsuite:
2016-02-12 Yao Qi <yao.qi@linaro.org>
* gdb.arch/arm-single-step-kernel-helper.c: New.
* gdb.arch/arm-single-step-kernel-helper.exp: New.
When I exercise GDBserver software single step, I see the following
error, which has been already handled by GDB properly.
In GDBserver log, we can see, GDBserver tries to single step instruction
on 0xb6e0a6e4, and destination address is 0xffff0fe0,
stop pc is 0xb6e0a6e4
Writing f001f0e7 to 0xffff0fe0 in process 7132
Failed to insert breakpoint at 0xffff0fe0 (Input/output error).
Failed to insert breakpoint at 0xffff0fe0 (-1).
(gdb) disassemble __aeabi_read_tp,+8
Dump of assembler code from 0xb6e0a6e0 to 0xb6e0a6e8:
0xb6e0a6e0 <__aeabi_read_tp+0>: mvn r0, #61440 ; 0xf000
0xb6e0a6e4 <__aeabi_read_tp+4>: sub pc, r0, #31
however, it fails inserting breakpoint there. This problem has already
fixed by GDB, see comments in arm-linux-tdep.c:arm_linux_software_single_step
/* The Linux kernel offers some user-mode helpers in a high page. We can
not read this page (as of 2.6.23), and even if we could then we
couldn't set breakpoints in it, and even if we could then the atomic
operations would fail when interrupted. They are all called as
functions and return to the address in LR, so step to there
instead. */
so we need to do the same thing in GDB side as well. This patch adds
a new field fixup in arm_get_next_pcs_ops, so that we can fix up PC
for arm-linux target. In this way, both GDB and GDBserver can single
step instructions going to kernel helpers.
gdb:
2016-02-12 Yao Qi <yao.qi@linaro.org>
* arch/arm-get-next-pcs.c (arm_get_next_pcs): Call
self->ops->fixup if it isn't NULL.
* arch/arm-get-next-pcs.h: Include gdb_vecs.h.
(struct arm_get_next_pcs_ops) <fixup>: New field.
* arch/arm-linux.c: Include common-regcache.h and
arch/arm-get-next-pcs.h.
(arm_linux_get_next_pcs_fixup): New function.
* arch/arm-linux.h (arm_linux_get_next_pcs_fixup): Declare.
* arm-linux-tdep.c (arm_linux_get_next_pcs_ops): Initialize
it with arm_linux_get_next_pcs_fixup.
(arm_linux_software_single_step): Move code to
arm_linux_get_next_pcs_fixup.
* arm-tdep.c (arm_get_next_pcs_ops): Initialize it.
gdb/gdbserver:
2016-02-12 Yao Qi <yao.qi@linaro.org>
* linux-arm-low.c (get_next_pcs_ops): Initialize it with
arm_linux_get_next_pcs_fixup.
In skip_artificial_frames we repeatedly call get_prev_frame_always until we get
a non-inline and non-tailcall frame assuming that there must be such a frame
eventually.
For record targets, however, we may have a frame chain that consists only of
artificial frames. This leads to a crash in get_frame_type when dereferencing a
NULL frame pointer.
Change skip_artificial_frames and skip_tailcall_frames to return NULL in such a
case and modify each caller to cope with a NULL return.
In frame_unwind_caller_pc and frame_unwind_caller_arch, we simply assert that
the returned value is not NULL. Their caller was supposed to check
frame_unwind_caller_id before calling those functions.
In other cases, we thrown an error.
In infcmd further move the skip_tailcall_frames call to the forward-stepping
case since we don't need a frame for reverse execution and we don't want to fail
because of that. Reverse-finish does make sense for a tailcall frame.
gdb/
* frame.h (skip_tailcall_frames): Update comment.
* frame.c (skip_artificial_frames, skip_tailcall_frames): Return NULL
if only artificial frames are found. Update comment.
(frame_unwind_caller_id): Handle NULL return.
(frame_unwind_caller_pc, frame_unwind_caller_arch): Assert that
skip_artificial_frames does not return NULL.
(frame_pop): Add an error if only tailcall frames are found.
* infcmd.c (finish_command): Move skip_tailcall_frames call into forward-
execution case. Add an error if only tailcall frames are found.
testsuite/
* gdb.btrace/tailcall-only.exp: New.
* gdb.btrace/tailcall-only.c: New.
* gdb.btrace/x86_64-tailcall-only.S: New.
* gdb.btrace/i686-tailcall-only.S: New.
Callers of frame_unwind_caller_* functions are supposed to check
frame_unwind_caller_id.
Add such a check to frame_info and treat an invalid caller ID as if the caller
PC were not available.
gdb/
* stack.c (frame_info): Check frame_unwind_caller_id.
Currently, you can cd to the gdb/testsuite/ dir and use
make check-parallel, instead of using FORCE_PARALLEL:
$ make -j8 check-parallel RUNTESTFLAGS="--target_board=native-gdbserver"
$ make -j8 check RUNTESTFLAGS="--target_board=native-gdbserver" FORCE_PARALLEL=1
But you can't do that in the build/gdb/ dir:
$ make check-parallel RUNTESTFLAGS="--target_board=native-gdbserver"
make: *** No rule to make target `check-parallel'. Stop.
I find check-parallel a bit more convenient, and more typo-proof, so
this patch makes it work from the gdb build dir too.
While documenting this in testsuite/README, I found that the parallel
testing mode would better be pulled out to its own section and
extended.
gdb/ChangeLog:
2016-02-11 Pedro Alves <palves@redhat.com>
* Makefile.in (check-parallel): New rule.
gdb/testsuite/ChangeLog:
2016-02-11 Pedro Alves <palves@redhat.com>
* README (Parallel testing): New section.
(GDB_PARALLEL): Rewrite.
(FORCE_PARALLEL): Document.
This function is never used, since it is superseded by
arm_linux_displaced_step_copy_insn.
gdb/ChangeLog:
* arm-tdep.c (arm_displaced_step_copy_insn): Remove.
(ARM displaced stepping support): Remove reference to
arm_displaced_step_copy_insn in comment.
* arm-tdep.h (arm_displaced_step_copy_insn): Remove.
* arm-linux-tdep.c (arm_linux_displaced_step_copy_insn): Remove
reference to arm_displaced_step_copy_insn in comment.
Almost obvious... change the type of some insn parameters, so that it
matches the rest of the code.
gdb/ChangeLog:
* arm-tdep.c (thumb_copy_unmodified_16bit): Change type of insn.
(thumb_copy_b): Likewise.
(arm_decode_b_bl_ldmstm): Likewise.
(thumb_copy_16bit_ldr_literal): Likewise.
(thumb_copy_pop_pc_16bit): Likewise.
This patch uses the target architecture rather then the objfile
architecture when encoding tracepoint actions.
The target architecture may contain additional registers. E.g. ARM VFP
registers. This information is needed to allow their collection. Since we
can never know whether the registers numbers in the target match the
binary's we have to use tdesc here.
One note about combined debuggers / multi-inferior from Pedro Alves:
In the combined debugger case taking Cell as the practical example that
gdb supports currently:
In that case, the main target_gdbarch() will be powerpc, but you may have set a
tracepoint on _spu_ code, which has a different gdbarch. so for that case,
target_gdbarch would be wrong. I think that in that case, we'd need to
find __the_ target/tdesc gdbarch that is (bfd) compatible with the
objfile's gdbarch.
I think cell/spu gdbserver doesn't support tracepoints, so we can ignore
this for now.
The multi-inferior/process case is somewhat related, but its simpler.
each inferior has its own gdbarch.
That is, target_gdbarch depends on the current inferior selected.
In fact, that just returns inferior->gdbarch nowaways.
No regressions, tested on ubuntu 14.04 ARMv7 and x86.
With gdbserver-{native,extended} / { -marm -mthumb }
gdb/ChangeLog:
* tracepoint.c (encode_actions_1): Use target_gdbarch () rather
than loc->gdbarch.
