Commit graph

1420 commits

Author SHA1 Message Date
Yao Qi
9f6a71b4bf Clear *VAL in regcache_raw_read_unsigned
We have function regcache_raw_read_unsigned defined in both GDB and
GDBserver, so that it is used in common like this,

  ULONGEST value;
  status = regcache_raw_read_unsigned (regcache, regnum, &value);

'value' is correctly set in GDB side, but may not be correctly set
in GDBserver, because &value is passed in regcache_raw_read_unsigned
but collect_register may only set part of the whole variable.  In my
test, I see the top half of 'value' is garbage.  This patch fixes this
problem by clearing *VAL before calling collect_register.

gdb/gdbserver:

2016-02-10  Yao Qi  <yao.qi@linaro.org>

	* regcache.c (regcache_raw_read_unsigned): Clear *VAL.
2016-02-10 16:40:52 +00:00
Simon Marchi
1e94266c4d Modernize configure.ac's
Using AC_OUTPUT with arguments has been deprecated for some time in
autoconf, even in version 2.64, which we are using.  This change should
not affect functionality.

I also removed the "exit 0"'s, they shouldn't be necessary.

gdb/ChangeLog:

	* configure.ac: Use AC_CONFIG_FILES instead of passing arguments
	to AC_OUTPUT.  Remove "exit 0" at the end.
	* configure: Regenerate.

gdb/testsuite/ChangeLog:

	* configure.ac: Use AC_CONFIG_FILES instead of passing arguments
	to AC_OUTPUT.
	* configure: Regenerate.

gdb/gdbserver/ChangeLog:

	* configure.ac: Use AC_CONFIG_FILES instead of passing arguments
	to AC_OUTPUT.
	* configure: Regenerate.
2016-02-09 09:01:58 -05:00
Simon Marchi
8adce0342f Fix siginfo C++ build error
Change the signature of gdbserver's siginfo_fixup functions so that it's
in line with gdb's.  This gets rid of the following build error in C++:

  /home/emaisin/src/binutils-gdb/gdb/gdbserver/linux-x86-low.c: In function ‘int x86_siginfo_fixup(siginfo_t*, void*, int)’:
  /home/emaisin/src/binutils-gdb/gdb/gdbserver/linux-x86-low.c:694:21: error: invalid conversion from ‘void*’ to ‘gdb_byte* {aka unsigned char*}’ [-fpermissive]
               FIXUP_32);
                       ^
  In file included from /home/emaisin/src/binutils-gdb/gdb/gdbserver/linux-x86-low.c:31:0:
  /home/emaisin/src/binutils-gdb/gdb/gdbserver/../nat/amd64-linux-siginfo.h:52:5: error:   initializing argument 2 of ‘int amd64_linux_siginfo_fixup_common(siginfo_t*, gdb_byte*, int, amd64_siginfo_fixup_mode)’ [-fpermissive]
   int amd64_linux_siginfo_fixup_common (siginfo_t *native, gdb_byte *inf,
       ^
  /home/emaisin/src/binutils-gdb/gdb/gdbserver/linux-x86-low.c:698:20: error: invalid conversion from ‘void*’ to ‘gdb_byte* {aka unsigned char*}’ [-fpermissive]
             FIXUP_X32);
                      ^
  In file included from /home/emaisin/src/binutils-gdb/gdb/gdbserver/linux-x86-low.c:31:0:
  /home/emaisin/src/binutils-gdb/gdb/gdbserver/../nat/amd64-linux-siginfo.h:52:5: error:   initializing argument 2 of ‘int amd64_linux_siginfo_fixup_common(siginfo_t*, gdb_byte*, int, amd64_siginfo_fixup_mode)’ [-fpermissive]
   int amd64_linux_siginfo_fixup_common (siginfo_t *native, gdb_byte *inf,
       ^

gdb/gdbserver/ChangeLog:

	* linux-aarch64-low.c (aarch64_linux_siginfo_fixup): Change
	void * to gdb_byte *.
	* linux-low.c (siginfo_fixup): Likewise.
	(linux_xfer_siginfo): Likewise.
	* linux-low.h (struct linux_target_ops) <siginfo_fixup>:
	Likewise.
	* linux-x86-low.c (x86_siginfo_fixup): Likewise.
2016-02-09 11:18:15 +00:00
Walfred Tedeschi
c23bbc1cda Revert "Fix build breakage"
This reverts commit 222cab58b7.
2016-02-09 11:36:54 +01:00
Walfred Tedeschi
222cab58b7 Fix build breakage
Add a cast to reinterpret a void* as a gdb_byte*.

2016-02-09  Walfred Tedeschi  <walfred.tedeschi@intel.com>

gdb/gdbserver/ChangeLog:

        * linux-x86-low.c (x86_siginfo_fixup): Add cast to gdb_byte*.
2016-02-09 11:26:13 +01:00
Walfred Tedeschi
93813b37c8 Merge gdb and gdbserver implementations for siginfo
Extract the compatible siginfo handling from amd64-linux-nat.c and
gdbserver/linux-x86-low to a new file nat/amd64-linux-siginfo.c.

2016-02-02  Walfred Tedeschi  <walfred.tedeschi@intel.com>

gdb/ChangeLog:

	* nat/amd64-linux-siginfo.c: New file.
	* nat/amd64-linux-siginfo.h: New file.
	* Makefile.in (HFILES_NO_SRCDIR): Add nat/amd64-linux-siginfo.h.
	(amd64-linux-siginfo.o): New rule.
	* config/i386/linux64.mh (NATDEPFILES): Add amd64-linux-siginfo.o.
	* amd64-linux-nat.c (nat/amd64-linux-siginfo.h): New include.
	(compat_siginfo_from_siginfo, siginfo_from_compat_siginfo)
	(compat_x32_siginfo_from_siginfo, siginfo_from_compat_x32_siginfo)
	(compat_timeval, compat_sigval, compat_x32_clock, cpt_si_pid)
	(cpt_si_uid, cpt_si_timerid, cpt_si_overrun, cpt_si_status)
	(cpt_si_utime, cpt_si_stime, cpt_si_ptr, cpt_si_addr, cpt_si_band)
	(cpt_si_fd, si_timerid, si_overrun): Move to nat/amd64-linux-siginfo.c.

gdb/gdbserver/ChangeLog:

	* configure.srv (x86_64-*-linux*): Add amd64-linux-siginfo.o
	to srv_tgtobj.
	(i[34567]86-*-linux*): Add amd64-linux-siginfo.o
	to srv_tgtobj.
	* linux-x86-low.c [__x86_64__]: Include
	"nat/amd64-linux-siginfo.h".
	(compat_siginfo_from_siginfo, siginfo_from_compat_siginfo)
	(compat_x32_siginfo_from_siginfo, siginfo_from_compat_x32_siginfo)
	(compat_timeval, compat_sigval, compat_x32_clock, cpt_si_pid)
	(cpt_si_uid, cpt_si_timerid, cpt_si_overrun, cpt_si_status)
	(cpt_si_utime, cpt_si_stime, cpt_si_ptr, cpt_si_addr, cpt_si_band)
	(cpt_si_fd, si_timerid, si_overrun): Move from
	nat/amd64-linux-siginfo.c.
	* Makefile.in (amd64-linux-siginfo.o:): New rule.
2016-02-02 11:42:56 +01:00
Simon Marchi
8424cc978c Import strchrnul from gnulib and use it
For a forthcoming patch, I need a "skip_to_colon" function.  I noticed
there are two skip_to_semicolon (one in gdb and one in gdbserver). I
thought we could put it in common/, and generalize it for any character.
It turns out that the strchrnul function does exactly that.  I imported
the corresponding module from gnulib, for those systems that do not have
it.

There are probably more places where this function can be used instead
of doing the work by hand (I am looking at
remote-utils.c::look_up_one_symbol).

gdb/ChangeLog:

	* remote.c (skip_to_semicolon): Remove.
	(remote_parse_stop_reply): Use strchrnul instead of
	skip_to_semicolon.
	* gnulib/update-gnulib.sh (IMPORTED_GNULIB_MODULES): Add
	strchrnul.
	* gnulib/aclocal.m4: Regenerate.
	* gnulib/config.in: Regenerate.
	* gnulib/configure: Regenerate.
	* gnulib/import/Makefile.am: Regenerate.
	* gnulib/import/Makefile.in: Regenerate.
	* gnulib/import/m4/gnulib-cache.m4: Regenerate.
	* gnulib/import/m4/gnulib-comp.m4: Regenerate.
	* gnulib/import/m4/rawmemchr.m4: New file.
	* gnulib/import/m4/strchrnul.m4: New file.
	* gnulib/import/rawmemchr.c: New file.
	* gnulib/import/rawmemchr.valgrind: New file.
	* gnulib/import/strchrnul.c: New file.
	* gnulib/import/strchrnul.valgrind: New file.

gdb/gdbserver/ChangeLog:

	* server.c (skip_to_semicolon):  Remove.
	(process_point_options): Use strchrnul instead of
	skip_to_semicolon.
2016-01-28 10:28:56 -05:00
Yao Qi
4d18591be9 Remove argument pc in get_next_pcs
Nowadays, get_next_pcs in linux_target_ops has two parameters PC
and REGCACHE.  Parameter PC looks redundant because it can be go
from REGCACHE.  The patch is to remove PC from the arguments for
various functions.

gdb:

2016-01-26  Yao Qi  <yao.qi@linaro.org>

	* arch/arm-get-next-pcs.c (thumb_deal_with_atomic_sequence_raw):
	Remove argument pc.  Get pc by regcache_read_pc.  Callers updated.
	(arm_deal_with_atomic_sequence_raw): Likewise.
	(thumb_get_next_pcs_raw): Likewise.
	(arm_get_next_pcs_raw): Likewise.
	(arm_get_next_pcs): Remove argument pc.  Callers updated.
	* arch/arm-get-next-pcs.h (arm_get_next_pcs): Update declaration.

gdb/gdbserver:

2016-01-26  Yao Qi  <yao.qi@linaro.org>

	* linux-arm-low.c (arm_gdbserver_get_next_pcs): Remove argument pc.
	* linux-low.c (install_software_single_step_breakpoints): Don't
	call regcache_read_pc.
	* linux-low.h (struct linux_target_ops) <get_next_pcs>: Remove
	argument pc.
2016-01-26 14:08:26 +00:00
Yao Qi
d80209703e [GDBserver] Use regcache_read_pc in install_software_single_step_breakpoints
In install_software_single_step_breakpoints, we've got the regcache
of current_thread, so we don't have to bother get_pc to get pc,
instead we can get pc from regcache directly.  Note that the callers
of install_software_single_step_breakpoints have already switched
current_thread to LWP.

Since the pc is got from regcache_read_pc, in the next patch, we can
get pc inside the implementation of *the_low_target.get_next_pcs and
stop passing pc to *the_low_target.get_next_pcs.

gdb/gdbserver:

2016-01-26  Yao Qi  <yao.qi@linaro.org>

	* linux-low.c (install_software_single_step_breakpoints): Call
	regcache_read_pc instead of get_pc.
2016-01-26 14:08:26 +00:00
Yao Qi
8b20733984 [GDBserver] Block and unblock SIGIO
Nowadays, GDBserver disables async io (by ignoring SIGIO) when process
a serial event, and enables async io (by installing signal handler) when
resume the inferior and wait.  GDBserver may miss SIGIO (by interrupt)
and doesn't process SIGIO in time, which is shown by
gdb.base/interrupt-noterm.exp.  In the test, GDB sends "continue &" and
then "interrupt".  if '\003' arrives at a period between GDBserver
receives vCont;c and enables async io, SIGIO is ignored because signal
handler isn't installed.  GDBserver waits for the inferior and can not
notice '\003' until it returns from wait.

This patch changes the code to install SIGIO handler early, but block
and unblock SIGIO as needed.  In this way, we don't remove SIGIO
handler, so SIGIO can't be ignored.  However, GDBserver needs to
remove the signal handler when connection is closed.

gdb/gdbserver:

2016-01-26  Yao Qi  <yao.qi@linaro.org>

	* remote-utils.c (remote_close) [!USE_WIN32API]: Ignore SIGIO.
	(unblock_async_io): Rename to ...
	(block_unblock_async_io): ... it.  New function.
	(enable_async_io): Don't install SIGIO handler.  Unblock it
	instead.
	(disable_async_io): Don't ignore SIGIO.  Block it instead.
	(initialize_async_io): Install SIGIO handler.  Don't call
	unblock_async_io.
2016-01-26 13:50:22 +00:00
Yao Qi
18879fef17 [GDBserver] Check input interrupt after reading in a packet
GDBserver may read some packet together with '\003' in one go.  We've
already checked '\003' first when reading packet by my patch,

  Check input interrupt first when reading packet
  https://sourceware.org/ml/gdb-patches/2016-01/msg00057.html

but if we don't check '\003' *after* each packet, the interrupt will
be processed next time GDBserver reads from the buffer, so that the
interrupt isn't processed in time.  For example, GDB sends vCont;c and
interrupt (see gdb.base/interrupt-noterm.exp), we'll resume the
inferior and wait once packet vCont;c is seen.  If we don't check the
interrupt character after vCont;c packet, interrupt character will stay
in the buffer unattended until GDBserver returns from the wait, which
may take a while.  Note that since we've read '\003' from file
descriptor, SIGIO signal handler input_interrupt doesn't help either.

This issue can be exposed by hacking the end of getpkt like
@@ -1041,6 +1050,9 @@ getpkt (char *buf)
        }
     }

+  if (readchar_bufcnt > 0)
+    gdb_assert (*readchar_bufp != '\003');
+
   return bp - buf;
 }

and this can trigger internal error,
(gdb) PASS: gdb.base/interrupt-noterm.exp: interrupt
Remote connection closed^M
(gdb) FAIL: gdb.base/interrupt-noterm.exp: inferior received SIGINT
Remote debugging from host 10.2.206.40^M
/home/yao/SourceCode/gnu/gdb/git/gdb/gdbserver/remote-utils.c:1054: A problem internal to GDBserver has been detected.^M
getpkt: Assertion `*readchar_bufp != '\003'' failed.^M

This patch is to peek the buffer, if it is '\003', consume it and call
*the_target->request_interrupt.

gdb/gdbserver:

2016-01-26  Yao Qi  <yao.qi@linaro.org>

	* remote-utils.c (getpkt): If the buffer isn't empty, and the
	first character is '\003', call *the_target->request_interrupt.
2016-01-26 13:50:22 +00:00
Yao Qi
a0f8e08a3c Remove new_thread_notify and dead_thread_notify
They were added by

  PATCH: Multithreaded debugging for gdbserver
  https://sourceware.org/ml/gdb-patches/2002-06/msg00157.html

but as a no-op, and the last usage of them was removed by

  [gdbserver/RFC/RFA] Implement multiprocess extensions, add linux multiproces support.
  https://sourceware.org/ml/gdb-patches/2009-03/msg00667.html

This patch is to remove them.

gdb/gdbserver:

2016-01-25  Yao Qi  <yao.qi@linaro.org>

	* remote-utils.c (new_thread_notify): Remove.
	(dead_thread_notify): Likewise.
	* remote-utils.h (new_thread_notify): Remove declaration.
	(dead_thread_notify): Likewise.
2016-01-25 16:11:43 +00:00
Marcin Kościelnicki
cc5fd9abe4 gdb.trace: Fix another expected message on continue.
Missed one message in bd0a71fa16, since it
didn't trigger on s390x or amd64 (fast tracepoint out of range due to
shared library usage), noticed on s390.

Pushed as obvious.

gdb/testsuite/ChangeLog:

	* gdb.trace/pending.exp: Fix expected message on continue.
2016-01-23 12:16:19 +01:00
Marcin Kościelnicki
99e8eb11cf gdb.trace: Fix write_inferior_data_ptr on 32-bit big-endian machines.
Noticed and tested on 31-bit s390.  This bug caused completely broken
fast tracepoints.

gdb/gdbserver/ChangeLog:

	* tracepoint.c (write_inferior_data_ptr): Cast to uintptr_t, so that
	it works properly on big-endian machines where sizeof (CORE_ADDR)
	!= sizeof (void *).
2016-01-22 15:03:47 +01:00
Pedro Alves
a994041db3 gdb: Respect CXXFLAGS when building with C++ compiler
Currently, even when built with --enable-build-with-cxx, gdb uses
CFLAGS instead of CXXFLAGS.  This commit fixes it.

CXXFLAGS set in the environment when configure was run is now honored
in the generated gdb/Makefile, and you can also override CXXFLAGS in
the command like at make time, with the usual 'make CXXFLAGS="..."'

Objects built with a C compiler (e.g., gnulib) still honor CFLAGS
instead.

gdb/ChangeLog:
2016-01-21  Pedro Alves  <palves@redhat.com>

	* Makefile.in (COMPILER_CFLAGS): New.
	(CXXFLAGS): Get it from configure.
	(INTERNAL_CFLAGS_BASE, INTERNAL_LDFLAGS): Use COMPILER_CFLAGS
	instead of CFLAGS.
	* build-with-cxx.m4 (GDB_AC_BUILD_WITH_CXX): Set and AC_SUBST
	COMPILER_CFLAGS.
	* configure: Regenerate.

gdb/gdbserver/ChangeLog:
2016-01-21  Pedro Alves  <palves@redhat.com>

	* Makefile.in (COMPILER_CFLAGS, CXXFLAGS): New.
	(INTERNAL_CFLAGS_BASE): Use COMPILER_CFLAGS instead of CFLAGS.
	* configure: Regenerate.
2016-01-21 11:18:45 +00:00
Yao Qi
f7a6a40dbc Detect the arm/thumb mode of code SIGRETURN or RT_SIGRETURN returns to
This patch fixes the following regression introduced by commit d0e59a68

step^M
39      } /* handler */^M
1: x/i $pc^M
=> 0x8740 <handler+80>: sub     sp, r11, #0^M
(gdb) step^M
^M
Program received signal SIGSEGV, Segmentation fault.^M
setitimer () at ../sysdeps/unix/syscall-template.S:81^M
81      ../sysdeps/unix/syscall-template.S: No such file or directory.^M
1: x/i $pc^M
=> 0xb6eff9c0 <setitimer>:      push    {r7}^M
(gdb) FAIL: gdb.base/sigstep.exp: continue to handler, si+advance in handler, step from handler: leave handler

in my test setting, program is compiled in arm mode, but the glibc
is built in thumb mode, so when we do 'step' to step over syscall
instruction svc for SIGRETURN, GDB should set breakpoint for arm mode
in the program, even though the current program in glibc is in thumb
mode.  Current GDB doesn't consider the case that the mode of program
SIGRETURN goes to can be different from current program mode.

In fact, GDB has taken care of this arm/thumb mode changes already,
see

/* Copy the value of next pc of sigreturn and rt_sigrturn into PC,
   return 1.  In addition, set IS_THUMB depending on whether we
   will return to ARM or Thumb code.  Return 0 if it is not a
   rt_sigreturn/sigreturn syscall.  */
static int
arm_linux_sigreturn_return_addr (struct frame_info *frame,
				 unsigned long svc_number,
				 CORE_ADDR *pc, int *is_thumb)

but in the commit d0e59a68

> -  arm_linux_sigreturn_return_addr (frame, svc_number, &return_addr, &is_thumb);
> +  if (svc_number == ARM_SIGRETURN || svc_number == ARM_RT_SIGRETURN)
> +    next_pc = arm_linux_sigreturn_next_pc (regcache, svc_number);

the IS_THUMB setting is lost, so it is a regression.

gdb:

2016-01-21  Yao Qi  <yao.qi@linaro.org>

	* arm-linux-tdep.c (arm_linux_sigreturn_next_pc): Add parameter
	is_thumb and set it according to CPSR saved on the stack.
	(arm_linux_get_next_pcs_syscall_next_pc): Pass is_thumb to
	arm_linux_sigreturn_next_pc.

gdb/gdbserver:

2016-01-21  Yao Qi  <yao.qi@linaro.org>

	* linux-arm-low.c (arm_sigreturn_next_pc): Add parameter
	is_thumb and set it according to CPSR saved on the stack.
	(get_next_pcs_syscall_next_pc): Pass is_thumb to
	arm_sigreturn_next_pc.
2016-01-21 07:48:50 +00:00
Yao Qi
6f69e52067 Replace some $ARCH_{get,set}_pc with linux_{get,set}_pc_64bit
This patch is the follow-up of
https://sourceware.org/ml/gdb-patches/2016-01/msg00164.html to provide
linux_{get,set}_pc_64bit functions.

Rebuild GDBserver with tilegx-linux-gcc.  Not tested.

I think about pc in Tile-GX a little bit.  Looks current Tile-GX
supports debugging 32-bit program (multi-arch), but PC is always
64-bit.  See this thread
https://sourceware.org/ml/gdb-patches/2013-02/msg00113.html
and GDBserver reads PC as 64-bit through ptrace.  However, if
the inferior is 32-bit, the PC in the target description and
regcache is 32-bit, so only 32-bit contents are sent back GDB.
Anyway, Tile-GX GDBserver may have some problems here, but this
patch doesn't change anything.

gdb/gdbserver:

2016-01-18  Yao Qi  <yao.qi@linaro.org>

	* linux-low.c (linux_set_pc_64bit): New function.
	(linux_get_pc_64bit): New function.
	* linux-low.h (linux_set_pc_64bit, linux_get_pc_64bit):
	Declare.
	* linux-sparc-low.c (debug_threads): Remove declaration.
	(sparc_get_pc): Remove.
	(the_low_target): Use linux_get_pc_64bit instead of
	sparc_get_pc.
	* linux-tile-low.c (tile_get_pc, tile_set_pc): Remove.
	(the_low_target): Use linux_get_pc_64bit and
	linux_set_pc_64bit.
2016-01-18 15:03:18 +00:00
Yao Qi
276d4552df Replace some $ARCH_{get,set}_pc with linux_{get,set}_pc_32bit
This patch adds a pair of new functions linux_get_pc_32bit and
linux_set_pc_32bit which get and set 32-bit register "pc" from
regcache.  This function can be used some targets and these own
$ARCH_{get,set}_pc are replaced by linux_{get,set}_pc_32bit
respectively.

This patch touches many targets, but I only have arm board to
test and no regression.  I also rebuilt nios2-linux GDBserver.
If it is right to go, I'll post the 64-bit counterpart later.

gdb/gdbserver:

2016-01-18  Yao Qi  <yao.qi@linaro.org>

	* linux-arm-low.c (debug_threads): Remove declaration.
	(arm_get_pc, arm_set_pc): Remove.
	(the_low_target): Use linux_get_pc_32bit and
	linux_set_pc_32bit.
	* linux-bfin-low.c (bfin_get_pc, bfin_set_pc): Remove.
	(the_low_target): Use linux_get_pc_32bit and
	linux_set_pc_32bit.
	* linux-cris-low.c (debug_threads): Remove declaration.
	(cris_get_pc, cris_set_pc,): Remove.
	(the_low_target): Use linux_get_pc_32bit and
	linux_set_pc_32bit.
	* linux-crisv32-low.c (debug_threads): Remove declaration.
	(cris_get_pc, cris_set_pc): Remove.
	(the_low_target): Use linux_get_pc_32bit and
	linux_set_pc_32bit.
	* linux-low.c: Include inttypes.h.
	(linux_get_pc_32bit, linux_set_pc_32bit): New functions.
	* linux-low.h (linux_get_pc_32bit, linux_set_pc_32bit): Declare.
	* linux-m32r-low.c (m32r_get_pc, m32r_set_pc): Remove.
	(the_low_target): Use linux_get_pc_32bit and
	linux_set_pc_32bit.
	* linux-m68k-low.c (m68k_get_pc, m68k_set_pc): Remove.
	(the_low_target): Use linux_get_pc_32bit and
	linux_set_pc_32bit.
	* linux-nios2-low.c (nios2_get_pc, nios2_set_pc): Remove.
	(the_low_target): Use linux_get_pc_32bit and
	linux_set_pc_32bit.
	* linux-sh-low.c (sh_get_pc, sh_set_pc): Remove.
	(the_low_target): Use linux_get_pc_32bit and
	linux_set_pc_32bit.
	* linux-xtensa-low.c (xtensa_get_pc, xtensa_set_pc): Remove.
	(the_low_target): Use linux_get_pc_32bit and
	linux_set_pc_32bit.
2016-01-18 14:59:11 +00:00
Gary Benson
eb0edac83f Fix gdbserver build failure on targets without fork
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.
2016-01-18 11:39:42 +00:00
Yao Qi
1b451dda5f [ARM] Make thumb2_breakpoint static again
This patch makes thumb2_breakpoint static.  When writing this patch,
I find the only reason we keep thumb2_breakpoint extern is that it
is used as an argument passed to arm_gdbserver_get_next_pcs.  However,
field arm_thumb2_breakpoint is only used in a null check in
thumb_get_next_pcs_raw, so I wonder why do need to pass thumb2_breakpoint
to arm_gdbserver_get_next_pcs.

thumb2_breakpoint was added by Daniel Jacobowitz in order to support
single-step IT block
https://sourceware.org/ml/gdb-patches/2010-01/msg00624.html  the logic
there was if we have 32-bit thumb-2 breakpoint defined, we can safely
single-step IT block, otherwise, we can't.  Daniel didn't want to use
16-bit thumb BKPT instruction, because it triggers even on instruction
which should be executed.  Secondly, using 16-bit thumb illegal
instruction on top of 32-bit thumb instruction may break the meaning of
original IT blocks, because the other 16-bit can be regarded as an
instruction.  See more explanations from Daniel's kernel patch
http://www.spinics.net/lists/arm-kernel/msg80476.html

Let us back to this patch, GDB/GDBserver can safely single step
IT block if thumb2_breakpoint is defined, but the single step logic
doesn't have to know the thumb-2 breakpoint instruction.  Only
breakpoint insertion mechanism decides to use which breakpoint
instruction.  In the software single step code, instead of pass
thumb2_breakpoint, we can pass a boolean variable
has_thumb2_breakpoint indicate whether the target has thumb-2
breakpoint defined, which is equivalent to the original code.

Regression tested on arm-linux.  No regression.

gdb:

2016-01-14  Yao Qi  <yao.qi@linaro.org>

	* arch/arm-get-next-pcs.c (arm_get_next_pcs_ctor): Change
	argument arm_thumb2_breakpoint to has_thumb2_breakpoint.
	(thumb_get_next_pcs_raw): Check has_thumb2_breakpoint
	instead.
	* arch/arm-get-next-pcs.h (struct arm_get_next_pcs)
	<arm_thumb2_breakpoint>: Remove.
	<has_thumb2_breakpoint>: New field.
	(arm_get_next_pcs_ctor): Update declaration.
	* arm-linux-tdep.c (arm_linux_software_single_step): Pass
	1 to arm_get_next_pcs_ctor.
	* arm-tdep.c (arm_software_single_step): Pass 0 to
	arm_get_next_pcs_ctor.

gdb/gdbserver:

2016-01-14  Yao Qi  <yao.qi@linaro.org>

	* linux-aarch32-low.c (thumb2_breakpoint): Make it static.
	* linux-aarch32-low.h (thumb2_breakpoint): Remove declaration.
	* linux-arm-low.c (arm_gdbserver_get_next_pcs): Pass 1 to
	arm_get_next_pcs_ctor.
2016-01-14 09:36:43 +00:00
Josh Stone
82075af2c1 Implement 'catch syscall' for gdbserver
This adds a new QCatchSyscalls packet to enable 'catch syscall', and new
stop reasons "syscall_entry" and "syscall_return" for those events.  It
is currently only supported on Linux x86 and x86_64.

gdb/ChangeLog:

2016-01-12  Josh Stone  <jistone@redhat.com>
	    Philippe Waroquiers  <philippe.waroquiers@skynet.be>

	* NEWS (Changes since GDB 7.10): Mention QCatchSyscalls and the
	syscall_entry and syscall_return stop reasons.  Mention GDB
	support for remote catch syscall.
	* remote.c (PACKET_QCatchSyscalls): New enum.
	(remote_set_syscall_catchpoint): New function.
	(remote_protocol_features): New element for QCatchSyscalls.
	(remote_parse_stop_reply): Parse syscall_entry/return stops.
	(init_remote_ops): Install remote_set_syscall_catchpoint.
	(_initialize_remote): Config QCatchSyscalls.
	* linux-nat.h (struct lwp_info) <syscall_state>: Comment typo.

gdb/doc/ChangeLog:

2016-01-12  Josh Stone  <jistone@redhat.com>
	    Philippe Waroquiers  <philippe.waroquiers@skynet.be>

	* gdb.texinfo (Remote Configuration): List the QCatchSyscalls packet.
	(Stop Reply Packets): List the syscall entry and return stop reasons.
	(General Query Packets): Describe QCatchSyscalls, and add it to the
	table and the detailed list of stub features.

gdb/gdbserver/ChangeLog:

2016-01-12  Josh Stone  <jistone@redhat.com>
	    Philippe Waroquiers  <philippe.waroquiers@skynet.be>

	* inferiors.h: Include "gdb_vecs.h".
	(struct process_info): Add syscalls_to_catch.
	* inferiors.c (remove_process): Free syscalls_to_catch.
	* remote-utils.c (prepare_resume_reply): Report syscall_entry and
	syscall_return stops.
	* server.h (UNKNOWN_SYSCALL, ANY_SYSCALL): Define.
	* server.c (handle_general_set): Handle QCatchSyscalls.
	(handle_query): Report support for QCatchSyscalls.
	* target.h (struct target_ops): Add supports_catch_syscall.
	(target_supports_catch_syscall): New macro.
	* linux-low.h (struct linux_target_ops): Add get_syscall_trapinfo.
	(struct lwp_info): Add syscall_state.
	* linux-low.c (handle_extended_wait): Mark syscall_state as an entry.
	Maintain syscall_state and syscalls_to_catch across exec.
	(get_syscall_trapinfo): New function, proxy to the_low_target.
	(linux_low_ptrace_options): Enable PTRACE_O_TRACESYSGOOD.
	(linux_low_filter_event): Toggle syscall_state entry/return for
	syscall traps, and set it ignored for all others.
	(gdb_catching_syscalls_p): New function.
	(gdb_catch_this_syscall_p): New function.
	(linux_wait_1): Handle SYSCALL_SIGTRAP.
	(linux_resume_one_lwp_throw): Add PTRACE_SYSCALL possibility.
	(linux_supports_catch_syscall): New function.
	(linux_target_ops): Install it.
	* linux-x86-low.c (x86_get_syscall_trapinfo): New function.
	(the_low_target): Install it.

gdb/testsuite/ChangeLog:

2016-01-12  Josh Stone  <jistone@redhat.com>
	    Philippe Waroquiers  <philippe.waroquiers@skynet.be>

	* gdb.base/catch-syscall.c (do_execve): New variable.
	(main): Conditionally trigger an execve.
	* gdb.base/catch-syscall.exp: Enable testing for remote targets.
	(test_catch_syscall_execve): New, check entry/return across execve.
	(do_syscall_tests): Call test_catch_syscall_execve.
2016-01-12 12:27:27 -08:00
Mike Frysinger
8f13a3ce8a gdbserver: use the new gdb warning helpers
We need to use -Wno-missing-prototypes for now as much of the code
sticks externs in local files and not in common headers.

2016-01-11  Mike Frysinger  <vapier@gentoo.org>

	* acinclude.m4: Include new ../warning.m4 file.
	* configure: Regenerated.
	* configure.ac: Replace all warning logic with AM_GDB_WARNINGS.
2016-01-12 10:34:57 -05:00
Mike Frysinger
5b3da067f0 gdbserver: fix various warnings
Delete unused funcs, update old prototypes, and mark local funcs
as static.  This doesn't cover all missing prototype warnings.
2016-01-12 10:34:17 -05:00
Pedro Alves
bc504a3117 Remove trademark acknowledgements throughout
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.
2016-01-12 15:03:11 +00:00
Yao Qi
5a0dd67a45 Check input interrupt first when reading packet
Hi,
I see timeout in one of several runs of random-signal.exp like this,

 $ (set -e; while true; do make check RUNTESTFLAGS="--target_board=native-gdbserver random-signal.exp"; done)

In about every five runs, we can see a fail,

PASS: gdb.base/random-signal.exp: continue
^CFAIL: gdb.base/random-signal.exp: stop with control-c (timeout)

after some investigation, I find '\003' may be discarded by GDBserver when
it is expecting '$'.  In GDB side, both normal packets and '\003' are sent
via function send, but GDBserver may receive them at any time, that is to
say, in the receive buffer in GDBserver, '\003' may appear before or after
normal packet.  However, current GDBserver doesn't handle this case.

With this patch applied, I don't see this fail in multiple runs.
Although there is still timeout fail, that is a different problem, the
next patch will fix it.

gdb/gdbserver:

2016-01-08  Yao Qi  <yao.qi@linaro.org>

	* remote-utils.c (getpkt): If c is '\003', call target hook
	request_interrupt.
2016-01-08 11:06:00 +00:00
Yao Qi
b2ca446f68 [ARM/AArch64] Fix -Werror=unused-const-variable warnings in GDBserver
This patch fixes gcc warning when build ARM GDBserver and AArch64
GDBserver,

AArch64 GDBserver:

gdb/gdbserver/linux-aarch32-low.h:36:29: error: 'thumb2_breakpoint' defined but not used [-Werror=unused-const-variable]
 static const unsigned short thumb2_breakpoint[] = { 0xf7f0, 0xa000 };
                             ^
gdb/gdbserver/linux-aarch32-low.h:34:29: error: 'thumb_breakpoint' defined but not used [-Werror=unused-const-variable]
 static const unsigned short thumb_breakpoint = 0xde01;
                             ^
gdb/gdbserver/linux-aarch32-low.h:28:28: error: 'arm_breakpoint' defined but not used [-Werror=unused-const-variable]
 static const unsigned long arm_breakpoint = arm_eabi_breakpoint;
                            ^
cc1: all warnings being treated as errors

ARM GDBserver:

gdb/gdbserver/linux-aarch32-low.h:34:29: error: 'thumb_breakpoint' defined but not used [-Werror=unused-const-variable]
 static const unsigned short thumb_breakpoint = 0xde01;
                             ^~~~~~~~~~~~~~~~

gdb/gdbserver/linux-aarch32-low.h:28:28: error: 'arm_breakpoint' defined but not used [-Werror=unused-const-variable]
 static const unsigned long arm_breakpoint = arm_eabi_breakpoint;
                            ^~~~~~~~~~~~~~

by simply moving these macros and variables to
linux-aarch32-low.c and only declare thumb2_breakpoint in
linux-aarch32-low.h, which is not perfect, and reveals some issues
in recent arm GDBserver software single step changes.  I'll post
follow-up patches.

gdb/gdbserver:

2016-01-06  Yao Qi  <yao.qi@linaro.org>

	* linux-aarch32-low.h (arm_abi_breakpoint): Move to
	linux-aarch32-low.c.
	(arm_eabi_breakpoint, arm_breakpoint): Likewise.
	(arm_breakpoint_len, thumb_breakpoint_len): Likewise.
	(thumb2_breakpoint, thumb2_breakpoint_len): Likewise.
	(thumb2_breakpoint): Declare.
	* linux-aarch32-low.c (arm_abi_breakpoint): Moved from
	linux-aarch32-low.h.
	(arm_eabi_breakpoint, arm_breakpoint): Likewise.
	(arm_breakpoint_len, thumb_breakpoint_len): Likewise.
	(thumb2_breakpoint, thumb2_breakpoint_len): Likewise.
2016-01-06 15:00:58 +00:00
Joel Brobecker
618f726fcb GDB copyright headers update after running GDB's copyright.py script.
gdb/ChangeLog:

        Update year range in copyright notice of all files.
2016-01-01 08:43:22 +04:00
Joel Brobecker
edd8878834 update copyright year printed by GDB, GDBserver and gdbreplay.
gdb/ChangeLog:

        * top.c (print_gdb_version): Change copyright year in version
        message.

gdb/gdbserver/ChangeLog:

        * gdbreplay.c (gdbreplay_version): Change copyright year in
        version message.
        * server.c (gdbserver_version): Likewise.
2016-01-01 08:26:14 +04:00
Patrick Palka
65da7f144f Use libiberty's crc32 implementation in gdbserver
Tested on x86_64-pc-linux-gnu native-gdbserver, no new regressions.

gdb/gdbserver/ChangeLog:

	* server.c (crc32_table): Delete.
	(crc32): Use libiberty's xcrc32 function.
2015-12-28 11:17:57 -05:00
Joel Brobecker
4abd5ed222 [lynxos] gdbserver hangs when killing inferior from GDB
With any program under GDBserver control on LynxOS, killing
the program from the debugger (using the "kill" command) causes
GDBserver to properly kill the inferior but GDBserver then hangs.

This change of behavior occured after the following change was
applied:

    commit f0ea042932e6922c90df3fd0001497d287b97677
    Date:   Mon Nov 30 16:05:27 2015 +0000
    Subject: gdbserver: don't exit until GDB disconnects

One of the changes introduced by the commit above is that
process_serial_event no longer calls exit after handling
the vKill packet. Instead, what happens is that we wait
until captured_main finds that we no longer have any inferior
to debug, at which point it throws_quit. This (normal) exception
is then expected to propagate all the way to the exception handle
in function "main", which calls exit.

However, before the exception gets propagated, the cleanups
are first executed, and one of the cleanups in question is
detach_or_kill_for_exit_cleanup, which was put in place by
captured_main. detach_or_kill_for_exit_cleanup is basically
a wrapper around detach_or_kill_for_exit, which iterates
over all inferiors, and kills them all.

In our case, we have only one inferior, which we have already
killed during the handling for the "vKill" packet. Unfortunately,
we did not properly clean our internal data for that inferior up,
and so detach_or_kill_for_exit thinks that we still have one inferior,
and therefore tries to kill it. This results in lynx_kill being
called, doing the following:

    lynx_ptrace (PTRACE_KILL, ptid, 0, 0, 0);
    lynx_wait (ptid, &status, 0);
    the_target->mourn (process);

The hang is caused by the call to lynx_wait, which waits for
an event from a process which does not exist...

This patch fixes the issue by enhancing lynx_mourn to clean
the threads and process list up.

gdb/gdbserver/ChangeLog:

        * lynx-low.c (lynx_delete_thread_callback): New function.
        (lynx_mourn): Properly delete our process and all of its
        threads.  Remove call to clear_inferiors.
2015-12-22 19:28:10 +04:00
Joel Brobecker
0e50fe5ca6 gdbserver crash in gdb/gdbserver/thread.c::thread_search_callback
Connecting GDB to a LynxOS-178 GDBserver causes GDBserver to crash:

    % gdbserver :4444 simple_main
    Process simple_main created; pid = 19
    Listening on port 4444
    Remote debugging from host 205.232.38.10
    Segmentation fault (core dumped)

The crash happens in thread_search_callback where the function
calls the_target->thread_stopped (via the thread_stopped macro)
without verifying whether the callback is NULL or not.

For the record, the regression was introduced by:

    commit a67a9faef0
    Date:   Mon Nov 30 16:05:26 2015 +0000
    Subject: gdbserver:prepare_access_memory: pick another thread

This patch avoids the crash by checking the value of the callback
first, before calling it.

gdb/gdbserver/ChangeLog:

        * target.c (thread_search_callback): Add check that
        the thread_stopped target callback is not NULL before
        calling it.
2015-12-22 19:26:17 +04:00
Yao Qi
35adc03f37 Use arm_eabi_breakpoint on aarch32
This patch is to get b37a6290 back again, which was removed by
d9311bfa by mistake.

gdb/gdbserver:

2015-12-21  Yao Qi  <yao.qi@linaro.org>

	* linux-aarch32-low.h [__aarch64__]: Use arm_abi_breakpoint
	arm breakpoint.
2015-12-21 13:55:45 +00:00
Antoine Tremblay
bd2b290956 Enable conditional breakpoints for targets that support software single step in GDBServer
This patch enables support for conditional breakpoints if the target supports
software single step.

This was disabled before as the implementations of software single step were too
simple as discussed in
https://sourceware.org/ml/gdb-patches/2015-04/msg01110.html.

Since these issues are now fixed support can be added back.

New tests passing :
PASS: gdb.base/cond-eval-mode.exp: set breakpoint condition-evaluation
target and related...

No regressions, tested on ubuntu 14.04 ARMv7 and x86.
With gdbserver-{native,extended} / { -marm -mthumb }

gdb/gdbserver/ChangeLog:

	* server.c (handle_query): Call target_supports_software_single_step.
2015-12-18 11:40:36 -05:00
Antoine Tremblay
7fe5e27e9d Enable software single stepping for while-stepping actions in GDBServer
This patch enables software single stepping if the targets support it,
to do while-stepping actions.

No regressions, tested on ubuntu 14.04 ARMv7 and x86.
With gdbserver-{native,extended} / { -marm -mthumb }

gdb/gdbserver/ChangeLog:

	* linux-low.c (single_step): New function.
	(linux_resume_one_lwp_throw): Call single_step.
	(start_step_over): Likewise.
2015-12-18 11:40:23 -05:00
Antoine Tremblay
d9311bfaf5 Support software single step on ARM in GDBServer
This patch teaches GDBServer how to software single step on ARM
linux by sharing code with GDB.

The arm_get_next_pcs function in GDB is now shared with GDBServer.  So
that GDBServer can use the function to return the possible addresses of
the next PC.

A proper shared context was also needed so that we could share the code,
this context is described in the arm_get_next_pcs structure.

Testing :

No regressions, tested on ubuntu 14.04 ARMv7 and x86.
With gdbserver-{native,extended} / { -marm -mthumb }

gdb/ChangeLog:

	* Makefile.in (ALL_TARGET_OBS): Append arm-get-next-pcs.o,
	arm-linux.o.
	(ALLDEPFILES): Append arm-get-next-pcs.c, arm-linux.c
	(arm-linux.o): New rule.
	(arm-get-next-pcs.o): New rule.
	* arch/arm-get-next-pcs.c: New file.
	* arch/arm-get-next-pcs.h: New file.
	* arch/arm-linux.h: New file.
	* arch/arm-linux.c: New file.
	* arm.c: Include common-regcache.c.
	(thumb_advance_itstate): Moved from arm-tdep.c.
	(arm_instruction_changes_pc): Likewise.
	(thumb_instruction_changes_pc): Likewise.
	(thumb2_instruction_changes_pc): Likewise.
	(shifted_reg_val): Likewise.
	* arm.h (submask): Move macro from arm-tdep.h
	(bit): Likewise.
	(bits): Likewise.
	(sbits): Likewise.
	(BranchDest): Likewise.
	(thumb_advance_itstate): Moved declaration from arm-tdep.h
	(arm_instruction_changes_pc): Likewise.
	(thumb_instruction_changes_pc): Likewise.
	(thumb2_instruction_changes_pc): Likewise.
	(shifted_reg_val): Likewise.
	* arm-linux-tdep.c: Include arch/arm.h, arch/arm-get-next-pcs.h
	arch/arm-linux.h.
	(arm_linux_get_next_pcs_ops): New struct.
	(ARM_SIGCONTEXT_R0, ARM_UCONTEXT_SIGCONTEXT,
	ARM_OLD_RT_SIGFRAME_SIGINFO, ARM_OLD_RT_SIGFRAME_UCONTEXT,
	ARM_NEW_RT_SIGFRAME_UCONTEXT, ARM_NEW_SIGFRAME_MAGIC): Move stack
	layout defines to arch/arm-linux.h.
	(arm_linux_sigreturn_next_pc_offset): Move to arch/arm-linux.c.
	(arm_linux_software_single_step): Adjust for arm_get_next_pcs
	implementation.
	* arm-tdep.c: Include arch/arm-get-next-pcs.h.
	(arm_get_next_pcs_ops): New struct.
	(submask): Move macro to arm.h.
	(bit): Likewise.
	(bits): Likewise.
	(sbits): Likewise.
	(BranchDest): Likewise.
	(thumb_instruction_changes_pc): Move to arm.c
	(thumb2_instruction_changes_pc): Likewise.
	(arm_instruction_changes_pc): Likewise.
	(shifted_reg_val): Likewise.
	(thumb_advance_itstate): Likewise.
	(thumb_get_next_pc_raw): Move to arm-get-next-pcs.c.
	(arm_get_next_pc_raw): Likewise.
	(arm_get_next_pc): Likewise.
	(thumb_deal_with_atomic_sequence_raw): Likewise.
	(arm_deal_with_atomic_sequence_raw): Likewise.
	(arm_deal_with_atomic_sequence): Likewise.
	(arm_get_next_pcs_read_memory_unsigned_integer): New function.
	(arm_get_next_pcs_addr_bits_remove): Likewise.
	(arm_get_next_pcs_syscall_next_pc): Likewise.
	(arm_get_next_pcs_is_thumb): Likewise.
	(arm_software_single_step): Adjust for arm_get_next_pcs
	implementation.
	* arm-tdep.h: (arm_get_next_pc): Remove declaration.
	(arm_get_next_pcs_read_memory_unsigned_integer):
	New declaration.
	(arm_get_next_pcs_addr_bits_remove): Likewise.
	(arm_get_next_pcs_syscall_next_pc): Likewise.
	(arm_get_next_pcs_is_thumb): Likewise.
	(arm_deal_with_atomic_sequence: Remove declaration.
	* common/gdb_vecs.h: Add CORE_ADDR vector definition.
	* configure.tgt (aarch64*-*-linux): Add arm-get-next-pcs.o,
	arm-linux.o.
	(arm*-wince-pe): Add arm-get-next-pcs.o.
	(arm*-*-linux*): Add arm-get-next-pcs.o, arm-linux.o,
	arm-get-next-pcs.o
	(arm*-*-netbsd*,arm*-*-knetbsd*-gnu): Add arm-get-next-pcs.o.
	(arm*-*-openbsd*): Likewise.
	(arm*-*-symbianelf*): Likewise.
	(arm*-*-*): Likewise.
	* symtab.h: Move CORE_ADDR vector definition to gdb_vecs.h.

gdb/gdbserver/ChangeLog:

	* Makefile.in (SFILES): Append arch/arm-linux.c,
	arch/arm-get-next-pcs.c.
	(arm-linux.o): New rule.
	(arm-get-next-pcs.o): New rule.
	* configure.srv (arm*-*-linux*): Add arm-get-next-pcs.o,
	arm-linux.o.
	* linux-aarch32-low.c (arm_abi_breakpoint): Remove macro.  Moved
	to linux-aarch32-low.c.
	(arm_eabi_breakpoint, arm_breakpoint): Likewise.
	(arm_breakpoint_len, thumb_breakpoint): Likewise.
	(thumb_breakpoint_len, thumb2_breakpoint): Likewise.
	(thumb2_breakpoint_len): Likewise.
	(arm_is_thumb_mode): Make non-static.
	* linux-aarch32-low.h (arm_abi_breakpoint): New macro.  Moved
	from linux-aarch32-low.c.
	(arm_eabi_breakpoint, arm_breakpoint): Likewise.
	(arm_breakpoint_len, thumb_breakpoint): Likewise.
	(thumb_breakpoint_len, thumb2_breakpoint): Likewise.
	(thumb2_breakpoint_len): Likewise.
	(arm_is_thumb_mode): New declaration.
	* linux-arm-low.c: Include arch/arm-linux.h
	aarch/arm-get-next-pcs.h, sys/syscall.h.
	(get_next_pcs_ops): New struct.
	(get_next_pcs_addr_bits_remove): New function.
	(get_next_pcs_is_thumb): New function.
	(get_next_pcs_read_memory_unsigned_integer): Likewise.
	(arm_sigreturn_next_pc): Likewise.
	(get_next_pcs_syscall_next_pc): Likewise.
	(arm_gdbserver_get_next_pcs): Likewise.
	(struct linux_target_ops) <arm_gdbserver_get_next_pcs>:
	Initialize.
	* linux-low.h: Move CORE_ADDR vector definition to gdb_vecs.h.
	* server.h: Include gdb_vecs.h.
2015-12-18 11:39:48 -05:00
Antoine Tremblay
68ce205943 Share regcache function regcache_raw_read_unsigned
This patch is in preparation for software single step support on ARM in
GDBServer. It adds a new shared function regcache_raw_read_unsigned and
regcache_raw_get_unsigned so that GDB and GDBServer can use the same call
to fetch a raw register into an integer.

No regressions, tested on ubuntu 14.04 ARMv7 and x86.
With gdbserver-{native,extended} / { -marm -mthumb }

gdb/ChangeLog:

	* Makefile.in (SFILES): Append common/common-regcache.c.
	(COMMON_OBS): Append common/common-regcache.o.
	(common-regcache.o): New rule.
	* common/common-regcache.h (register_status) New enum.
	(regcache_raw_read_unsigned): New declaration.
	* common/common-regcache.c: New file.
	* regcache.h (enum register_status): Move to common-regcache.h.
	(regcache_raw_read_unsigned): Likewise.
	(regcache_raw_get_unsigned): Likewise.

gdb/gdbserver/ChangeLog:

	* Makefile.in (SFILES): Append common/common-regcache.c.
	(OBS): Append common-regcache.o.
	(common-regcache.o): New rule.
	* regcache.c (init_register_cache): Initialize cache to
	REG_UNAVAILABLE.
	(regcache_raw_read_unsigned): New function.
	* regcache.h (REG_UNAVAILABLE, REG_VALID): Replaced by shared
	register_status enum.
2015-12-18 11:39:21 -05:00
Antoine Tremblay
fa5308bdcc Replace breakpoint_reinsert_addr by get_next_pcs operation in GDBServer
This patch in preparation for software single step support on ARM. It refactors
breakpoint_reinsert_addr into get_next_pcs so that multiple location can be
returned.

When software single stepping there can be multiple possible next addresses
because we're stepping over a conditional branch instruction, for example.

The operation get_next_pcs handles that by returning a vector of all the
possible next addresses.

Software breakpoints are installed at each location returned.

No regressions, tested on ubuntu 14.04 ARMv7 and x86.
With gdbserver-{native,extended} / { -marm -mthumb }

gdb/gdbserver/ChangeLog:

	* linux-aarch64-low.c (the_low_targets): Rename
	breakpoint_reinsert_addr to get_next_pcs.
	* linux-arm-low.c (the_low_targets): Likewise.
	* linux-bfin-low.c (the_low_targets): Likewise.
	* linux-cris-low.c (the_low_targets): Likewise.
	* linux-crisv32-low.c (the_low_targets): Likewise.
	* linux-low.c (can_software_single_step): Likewise.
	(install_software_single_step_breakpoints): New function.
	(start_step_over): Use install_software_single_step_breakpoints.
	* linux-low.h: New CORE_ADDR vector.
	(struct linux_target_ops) Rename breakpoint_reinsert_addr to
	get_next_pcs.
	* linux-mips-low.c (the_low_targets): Likewise.
	* linux-nios2-low.c (the_low_targets): Likewise.
	* linux-sparc-low.c (the_low_targets): Likewise.
2015-12-18 11:33:58 -05:00
Pedro Alves
4a6ed09b0f Remove support for LinuxThreads and vendor 2.4 kernels w/ backported NPTL
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.
2015-12-17 14:20:51 +00:00
Pedro Alves
7544db951a Fix -Wno-unknown-warning support detection
Ref: https://sourceware.org/ml/gdb/2015-12/msg00024.html

We have code in configure.ac that tries to detect whether the compiler
supports each warning and suppress it if not, but that doesn't work
with "-Wno-" options, because gcc doesn't error out for
-Wno-unknown-warning unless other diagnostics are being produced.

See https://gcc.gnu.org/onlinedocs/gcc/Warning-Options.html.

Handle this by checking whether -Wfoo works when we actually want
-Wno-foo.

gdb/ChangeLog:
2015-12-16  Pedro Alves  <palves@redhat.com>

	* configure.ac (compiler warning flags): When testing a
	-Wno-foo option, check whether -Wfoo works instead.
	* configure: Regenerate.

gdb/gdbserver/ChangeLog:
2015-12-16  Pedro Alves  <palves@redhat.com>

	* configure.ac (compiler warning flags): When testing a
	-Wno-foo option, check whether -Wfoo works instead.
	* configure: Regenerate.
2015-12-16 22:56:49 +00:00
Don Breazeal
8020350c52 Target remote mode fork and exec event support
This patch implements support for fork and exec events with target remote
mode Linux targets.  For such targets with Linux kernels 2.5.46 and later,
this enables follow-fork-mode, detach-on-fork and fork and exec
catchpoints.

The changes required to implement this included:

 * Don't exit from gdbserver if there are still active inferiors.

 * Allow changing the active process in remote mode.

 * Enable fork and exec events in remote mode.

 * Print "Ending remote debugging" only when disconnecting.

 * Combine remote_kill and extended_remote_kill into a single function
   that can handle the multiple inferior case for target remote.  Also,
   the same thing for remote_mourn and extended_remote_mourn.

 * Enable process-style ptids in target remote.

 * Remove restriction on multiprocess mode in target remote.

gdb/gdbserver/ChangeLog:

	* server.c (process_serial_event): Don't exit from gdbserver
	in remote mode if there are still active inferiors.

gdb/ChangeLog:

	* inferior.c (number_of_live_inferiors): New function.
	(have_live_inferiors): Use number_of_live_inferiors in place
	of duplicate code.
	* inferior.h (number_of_live_inferiors): Declare new function.
	* remote.c (set_general_process): Remove restriction on target
	remote mode.
	(remote_query_supported): Likewise.
	(remote_detach_1): Exit in target remote mode only when there
	is just one live inferior left.
	(remote_disconnect): Unpush the target directly instead of
	calling remote_mourn.
	(remote_kill): Rewrite function to handle both target remote
	and extended-remote.  Call remote_kill_k.
	(remote_kill_k): New function.
	(extended_remote_kill): Delete function.
	(remote_mourn, extended_remote_mourn): Combine functions into
	one, remote_mourn, and enable extended functionality for target
	remote.
	(remote_pid_to_str): Enable "process" style ptid string for
	target remote.
	(remote_supports_multi_process): Remove restriction on target
	remote mode.
2015-12-14 11:18:05 -08:00
Yao Qi
db91f50261 Understand arm breakpoints in aarch64_breakpoint_at
AArch64 GDBserver can debug ARM program, and it should recognize
various arm breakpoint instructions.  This patch should be included
in 17b1509a.

gdb/gdbserver:

2015-12-11  Yao Qi  <yao.qi@linaro.org>

	* linux-aarch64-low.c (aarch64_breakpoint_at): Call
	arm_breakpoint_at if the process is 32-bit.
2015-12-11 11:19:52 +00:00
Yao Qi
b37a6290be Use arm_eabi_breakpoint on aarch32
Nowdays, GDBserver chooses arm breakpoint instructions by checking
macro __ARM_EABI__.  When aarch64 GDBserver debugs arm program,
arm_eabi_breakpoint is still needed, but __ARM_EABI__ isn't defined
in aarch64 compiler.  This causes GDBserver chooses the wrong
breakpoint instruction for arm program.  This patch fixes it.

gdb/gdbserver:

2015-12-11  Yao Qi  <yao.qi@linaro.org>

	* linux-aarch32-low.c [__aarch64__]: Use arm_abi_breakpoint
	arm breakpoint.
2015-12-11 11:19:52 +00:00
Yao Qi
17b1509aac Support Z0 packet in AArch64 multi-arch debugging
In commit 6085d6f6, Z0 packet is disabled in aarch64 GDBserver if
the inferior is 32-bit or there may be multiple inferiors, because
Z0 packet isn't supported for arm then.  Recently, Z0 packet
is supported in arm target, so we don't have such limitation in
aarch64 GDBserver, that is to say, aarch64 GDBserver can use Z0
packet in multi-arch/multi-inferior debugging when the inferior's
arch is arm.

Part of this patch is to revert 6085d6f6, and the rest of the patch
is to move some breakpoint related arm_* functions into
linux-aarch32-low.c in order to share them between arm and aarch64.

This patch is regression tested on aarch64-linux for debugging both
aarch64 programs and arm programs respectively.

gdb/gdbserver:

2015-12-07  Yao Qi  <yao.qi@linaro.org>

	* configure.srv: Append arm.o to srv_tgtobj for
	aarch64*-*-linux* target.
	* linux-aarch32-low.c (arm_abi_breakpoint): New macro.  Moved
	from linux-arm-low.c.
	(arm_eabi_breakpoint, arm_breakpoint): Likewise.
	(arm_breakpoint_len, thumb_breakpoint): Likewise.
	(thumb_breakpoint_len, thumb2_breakpoint): Likewise.
	(thumb2_breakpoint_len): Likewise.
	(arm_is_thumb_mode, arm_breakpoint_at): Likewise.
	(arm_breakpoint_kinds): Likewise.
	(arm_breakpoint_kind_from_pc): Likewise.
	(arm_sw_breakpoint_from_kind): Likewise.
	(arm_breakpoint_kind_from_current_state): Likewise.
	* linux-aarch32-low.h (arm_breakpoint_kind_from_pc): Declare.
	(arm_sw_breakpoint_from_kind): Declare.
	(arm_breakpoint_kind_from_current_state): Declare.
	(arm_breakpoint_at): Declare.
	* linux-aarch64-low.c (aarch64_sw_breakpoint_from_kind): Call
	arm_sw_breakpoint_from_kind if process is 32-bit.
	(aarch64_breakpoint_kind_from_pc): New function.
	(aarch64_breakpoint_kind_from_current_state): New function.
	(the_low_target): Initialize fields breakpoint_kind_from_pc
	and breakpoint_kind_from_current_state.
	* linux-arm-low.c (arm_breakpoint_kinds): Move to
	linux-aarch32-low.c.
	(arm_abi_breakpoint, arm_eabi_breakpoint): Likewise.
	(arm_breakpoint, arm_breakpoint_len): Likewise.
	(thumb_breakpoint, thumb_breakpoint_len): Likewise.
	(thumb2_breakpoint, thumb2_breakpoint_len): Likewise.
	(arm_is_thumb_mode): Likewise.
	(arm_breakpoint_at): Likewise.
	(arm_breakpoint_kind_from_pc): Likewise.
	(arm_sw_breakpoint_from_kind): Likewise.
	(arm_breakpoint_kind_from_current_state): Likewise.

	Revert:
	2015-08-04  Yao Qi  <yao.qi@linaro.org>

	* linux-aarch64-low.c (aarch64_supports_z_point_type): Return
	0 for Z_PACKET_SW_BP if it may be used in multi-arch debugging.
	* server.c (extended_protocol): Remove "static".
	* server.h (extended_protocol): Declare it.
2015-12-07 15:56:31 +00:00
Josh Stone
ece66d6510 gdbserver: set ptrace flags after creating inferiors
Rename target_ops.arch_setup to .post_create_inferior.  In the Linux
hook, continue calling the low arch setup, then also set ptrace flags.
This corrects the possibility of running without flags, demonstrated by
a new test that would fail to catch a fork before.

gdb/gdbserver/ChangeLog:

2015-12-04  Josh Stone  <jistone@redhat.com>

	* target.h (struct target_ops) <arch_setup>: Rename to ...
	(struct target_ops) <post_create_inferior>: ... this.
	(target_arch_setup): Rename to ...
	(target_post_create_inferior): ... this, calling post_create_inferior.
	* server.c (start_inferior): Update target_arch_setup calls to
	target_post_create_inferior.
	* linux-low.c (linux_low_ptrace_options): Forward declare.
	(linux_arch_setup): Update its comment for general use.
	(linux_post_create_inferior): New, run arch_setup and setup ptrace.
	(struct linux_target_ops): Use linux_post_create_inferior.
	* lynx-low.c (struct lynx_target_ops): Update arch_setup stub comment
	to post_create_inferior.
	* nto-low.c (struct nto_target_ops): Likewise.
	* spu-low.c (struct spu_target_ops): Likewise.
	* win32-low.c (struct win32_target_ops): Likewise.

gdb/testsuite/ChangeLog:

2015-12-04  Josh Stone  <jistone@redhat.com>

	* gdb.base/catch-fork-static.exp: New.
2015-12-04 18:25:26 -08:00
Antoine Tremblay
e58c48b4c8 Remove duplicate arch/arm.h include in linux-arm-low.c.
A duplicate include arm/arm.h was introduced, remove it.
Pushed as obvious.

gdb/gdbserver/ChangeLog:

	* linux-arm-low.c: Remove duplicate arch/arm.h include.
2015-12-03 14:00:24 -05:00
Antoine Tremblay
fbec895607 Remove too simple breakpoint_reinsert_addr implementations.
This patch removes too simple implementations of the breakpoint_reinsert_addr
operation.

The only reason to keep them around was to support thread events when
PTRACE_EVENT_CLONE was not present but this support has been removed in a
previous patch.

No regressions, tested on ubuntu 14.04 ARMv7 and x86.
With gdbserver-{native,extended} / { -marm -mthumb }

Also compilation was tested on aarch64, bfin, cris, crisv32,
m32r, mips, nios2, ppc, s390, sparc, tic6x, tile,  xtensa.

gdb/gdbserver/ChangeLog:

	* linux-arm-low.c (arm_reinsert_addr): Remove function.
	(struct linux_target_ops <breakpoint_reinsert_addr>: Set to NULL.
	* linux-cris-low.c (cris_reinsert_addr> Remove function.
	(struct linux_target_ops) <breakpoint_reinsert_addr>: Set to NULL.
	* linux-crisv32-low.c (cris_reinsert_addr): Remove function.
	(struct linux_target_ops) <breakpoint_reinsert_addr>: Set to NULL.
	* linux-mips-low.c (mips_reinsert_addr): Remove function.
	(struct linux_target_ops) <breakpoint_reinsert_addr>: Set to NULL.
	* linux-nios2-low.c (nios2_reinsert_addr): Remove function.
	(struct linux_target_ops) <breakpoint_reinsert_addr>: Set to NULL.
	* linux-sparc-low.c (sparc_reinsert_addr): Remove function.
	(struct linux_target_ops) <breakpoint_reinsert_addr>: Set to NULL.
2015-11-30 15:19:11 -05:00
Antoine Tremblay
9b4c5f878f Remove support for thread events without PTRACE_EVENT_CLONE in GDBServer.
This patch removes support for thread events if PTRACE_EVENT_CLONE is not
supported in GDBServer.

Before, on systems that did not support PTRACE_EVENT_CLONE, both GDB and
GDBServer coordinated with libthread_db.so to insert breakpoints at magic
locations in libpthread.so, in order to break at thread creation and thread
death.

Simple software single stepping support was implemented to step over these
breakpoints in case there was no hardware single stepping support. However,
these simple software single stepping implementations were not fit for any other
use as discussed in :
https://sourceware.org/ml/gdb-patches/2015-04/msg01110.html

These too simple implementations conflict with ongoing work to make proper
implementations of software single stepping in GDBServer.

The problem is that if some implementations are correct and others are not and
only there for the thread magic breakpoint, we can't enable features based
solely software single step support since some would be broken.

To keep the incorrect implementations and allow the new proper ones at the same
time we would need to implement fallback code and it quickly becomes ugly and
confusing with multiple checks for legacy software single step or proper
software single step.

However, PTRACE_EVENT_CLONE was first introduced in Linux 2.5.46,
released in November 2002.

So I think it's reasonable to just remove support for kernels that don't support
PTRACE_EVENT_CLONE, and sidestep the libthread_db breakpoints issues entirely.

This thread on the mailling list discusses the issue :
https://sourceware.org/ml/gdb/2015-10/msg00078.html

No regressions, tested on ubuntu 14.04 ARMv7 and x86.
With gdbserver-{native,extended} / { -marm -mthumb }

gdb/gdbserver/ChangeLog:

	* linux-low.c (linux_look_up_symbols): Don't call
	linux_supports_traceclone.
	* linux-low.h (thread_db_init): Remove use_events argument.
	* thread-db.c (thread_db_use_event): Remove global variable.
	(struct thread_db) <td_thr_event_enable_p>: Remove field.
	(struct thread_db) <td_create_bp>: Remove field.
	(thread_db_create_event): Remove function.
	(thread_db_enable_reporting): Likewise.
	(find_one_thread): Don't check for thread_db_use_events.
	(attach_thread): Likewise.
	(thread_db_load_search): Remove td_thr_event_enable_p initialization.
	(try_thread_db_load_1): Don't check for thread_db_use_events.
	(thread_db_init): Remove use_events argument and thread events
	handling.
	(remove_thread_event_breakpoints): Remove function.
	(thread_db_detach): Remove call to remove_thred_event_breakpoints.
2015-11-30 15:18:57 -05:00
Antoine Tremblay
7d00775ece Refactor queries for hardware and software single stepping support in GDBServer.
Before this patch there was only one call: can_hardware_single_step. Its
implementation was a check on breakpoint_reinsert_addr if NULL it assumed
that the target could hardware single step.

This patch prepares for the case where this is not true anymore.

In order to improve software single stepping in GDBServer the
breakpoint_reinsert_addr operation of targets that had a very simple
software implementation used only for stepping over thread creation events
will be removed.

This will create a case where a target does not support hardware single
step and has the operation breakpoint_reinsert_addr set to NULL, thus
can_hardware_single_step needs to be implemented another way.

A new target operation supports_hardware_single_step is introduced and is
to return true if the target does support such a feature, support for the
feature is manually hardcoded.

Note that the hardware single step support was enabled as per the current
behavior, I did not check if tile for example really has ptrace singlestep
support but since the current implementation assumed it had, I kept it
that way.

No regressions on Ubuntu 14.04 on ARMv7 and x86.
With gdbserver-{native,extended} / { -marm -mthumb }

Compilation tested on: aarch64,arm,bfind,crisv32,m32r,ppc,s390,tic6x,tile,
xtensa.
Not tested : sh.

gdb/gdbserver/ChangeLog:

	* linux-aarch64-low.c (aarch64_supports_hardware_single_step):
	New function.
	(struct linux_target_ops) <supports_hardware_single_step>: Initialize.
	* linux-arm-low.c (arm_supports_hardware_single_step): New function.
	(struct linux_target_ops) <supports_hardware_single_step>: Initialize.
	* linux-bfin-low.c (bfin_supports_hardware_single_step): New function.
	(struct linux_target_ops) <bfin_supports_hardware_single_step>:
	Initialize.
	* linux-crisv32-low.c (cris_supports_hardware_single_step):
	New function.
	(struct linux_target_ops) <supports_hardware_single_step>: Initialize.
	* linux-low.c (can_hardware_single_step): Use
	supports_hardware_single_step.
	(can_software_single_step): New function.
	(start_step_over): Call can_software_single_step.
	(linux_supports_hardware_single_step): New function.
	(struct target_ops) <supports_software_single_step>: Initialize.
	* linux-low.h (struct linux_target_ops)
	<supports_hardware_single_step>: Initialize.
	* linux-m32r-low.c (m32r_supports_hardware_single_step): New function.
	(struct linux_target_ops) <supports_hardware_single_step>: Initialize.
	* linux-ppc-low.c (ppc_supports_hardware_single_step): New function.
	(struct linux_target_ops) <supports_hardware_single_step> Initialize.
	* linux-s390-low.c (s390_supports_hardware_single_step): New function.
	(struct linux_target_ops) <supports_hardware_single_step>: Initialize.
	* linux-sh-low.c (sh_supports_hardware_single_step): New function.
	(struct linux_target_ops) <supports_hardware_single_step>: Initialize.
	* linux-tic6x-low.c (tic6x_supports_hardware_single_step): New function.
	(struct linux_target_ops) <tic6x_supports_hardware_single_step>:
	Initialize.
	* linux-tile-low.c (tile_supports_hardware_single_step): New function.
	(struct linux_target_ops) <tile_supports_hardware_single_step>:
	Initialize.
	* linux-x86-low.c (x86_supports_hardware_single_step) New function.
	(struct linux_target_ops) <supports_hardware_single_step>: Initialize.
	* linux-xtensa-low.c (xtensa_supports_hardware_single_step):
	New function.
	(struct linux_target_ops) <supports_hardware_single_step>: Initialize.
	* target.h (struct target_ops): <supports_software_single_step>:
	New field.
	(target_supports_software_single_step): New macro.
2015-11-30 15:17:36 -05:00
Antoine Tremblay
2d97cd356e Fix instruction skipping when using software single step in GDBServer
Without this patch, when doing a software single step, with for example
a conditional breakpoint, gdbserver would wrongly avance the pc of
breakpoint_len and skips an instruction.

This is due to gdbserver assuming that it's hardware single stepping.
When it resumes from the breakpoint address it expects the trap to be
caused by ptrace and if it's rather caused by a software breakpoint
it assumes this is a permanent breakpoint and that it needs to skip
over it.

However when software single stepping, this breakpoint is legitimate as
it's the reinsert breakpoint gdbserver has put in place to break at
the next instruction. Thus gdbserver wrongly advances the pc and skips
an instruction.

This patch fixes this behavior so that gdbserver checks if it is a
reinsert breakpoint from software single stepping. If it is it won't
advance the pc. And if there's no reinsert breakpoint there we assume
then that it's a permanent breakpoint and advance the pc.

Here's a commented log of what would happen before and after the fix on
gdbserver :

/* Here there is a conditional breakpoint at 0x10428 that needs to be
stepped over. */

Need step over [LWP 11204]? yes, found breakpoint at 0x10428
...
/* e7f001f0 is a breakpoint instruction on arm
   Here gdbserver writes the software breakpoint we would like to hit
*/
Writing e7f001f0 to 0x0001042c in process 11204
...
Resuming lwp 11220 (continue, signal 0, stop not expected)
  pending reinsert at 0x10428
stop pc is 00010428
  continue from pc 0x10428
...

/* Here gdbserver hit the software breakpoint that was in place
   for the step over */

stop pc is 0001042c
pc is 0x1042c
step-over for LWP 11220.11220 executed software breakpoint
Finished step over.
Could not find fast tracepoint jump at 0x10428 in list (reinserting).

/* Here gdbserver writes back the original instruction */
Writing e50b3008 to 0x0001042c in process 11220
Step-over finished.
Need step over [LWP 11220]? No

/* Here because gdbserver assumes this is a permenant breakpoint it advances
the pc of breakpoint_len, in this case 4 bytes, so we have just skipped
the instruction that was written back here :
Writing e50b3008 to 0x0001042c in process 11220
*/

stop pc is 00010430
pc is 0x10430
Need step over [LWP 11220]? No, no breakpoint found at 0x10430
Proceeding, no step-over needed
proceed_one_lwp: lwp 11220
stop pc is 00010430

This patch fixes this situation and we get the right behavior :

Writing e50b3008 to 0x0001042c in process 11245
Hit a gdbserver breakpoint.
Hit a gdbserver breakpoint.
Step-over finished.
proceeding all threads.
Need step over [LWP 11245]? No
stop pc is 0001042c
pc is 0x1042c
Need step over [LWP 11245]? No, no breakpoint found at 0x1042c
Proceeding, no step-over needed
proceed_one_lwp: lwp 11245
stop pc is 0001042c
pc is 0x1042c
Resuming lwp 11245 (continue, signal 0, stop not expected)
stop pc is 0001042c
  continue from pc 0x1042c

It also works if the value at 0x0001042c is a permanent breakpoint.
If so gdbserver will finish the step over, remove the reinserted breakpoint,
resume at that location and on the next SIGTRAP gdbserver will trigger
the advance PC condition as reinsert_breakpoint_inserted_here will be false.

I also tested this against bp-permanent.exp on arm (with a work in progress
software single step patchset) without any regressions.

It's also tested against x86 bp-permanent.exp without any regression.

So both software and hardware single step are tested.

No regressions on Ubuntu 14.04 on ARMv7 and x86.
With gdbserver-{native,extended} / { -marm -mthumb }

gdb/gdbserver/ChangeLog:

	* linux-low.c (linux_wait_1): Fix pc advance condition.
	* mem-break.c (reinsert_breakpoint_inserted_here): New function.
	* mem-break.h (reinsert_breakpoint_inserted_here): New declaration.
2015-11-30 15:16:22 -05:00
Antoine Tremblay
769ef81fec Fix breakpoint size when stepping over a permanent breakpoint in GDBServer.
When manually stepping over a permanent breakpoint on ARM we need to fetch the
right breakpoint size based on the current instruction set used.

Since this is not encoded in the stop_pc, the instruction mode needs to be
fetched from the CPSR register.

This is done by introducing a new target operation called :
breakpoint_kind_from_current_state.

For other targets that do not need this, breakpoint_kind_from_pc is used.

No regressions, tested on ubuntu 14.04 ARMv7 and x86.
With gdbserver-{native,extended} / { -marm -mthumb }

gdb/gdbserver/ChangeLog:

	* linux-arm-low.c (arm_is_thumb_mode): New function.
	(arm_breakpoint_at): Use arm_is_thumb_mode.
	(arm_breakpoint_kind_from_current_state): New function.
	(struct linux_target_ops) <breakpoint_kind_from_current_state>:
	Initialize.
	* linux-low.c (linux_wait_1): Call breakpoint_kind_from_current_state.
	(linux_breakpoint_kind_from_current_state): New function.
	(struct target_ops <breakpoint_kind_from_current_state>: Initialize.
	* linux-low.h (struct linux_target_ops)
	<breakpoint_kind_from_current_state>: New field.
	* target.h (struct target_ops): Likewise.
	(target_breakpoint_kind_from_current_state): New macro.
2015-11-30 15:08:04 -05:00