Hi,
We see the following fail in the real remote testing...
(gdb) Executing on target: kill -9 29808 (timeout = 300)
spawn [open ...]^M
sh: 1: kill: No such process
The test tries to kill gdbserver in this way:
set server_pid [exp_pid -i [board_info target fileid]]
remote_exec target "kill -9 $server_pid"
in native testing, we'll get the pid of spawned gdbserver, however, in
remote testing, we'll get the pid of ssh session, since we start
gdbserver on the remote target through ssh. The pid on build doesn't
exist on target.
In this patch, we tweak server-kill.c to get the parent pid, which is
the pid of GDBserver. GDB gets it and kill GDBserver on target.
gdb/testsuite:
2014-10-11 Yao Qi <yao@codesourcery.com>
* gdb.server/server-kill.c: Include sys/types.h and unistd.h.
(main): Call getppid.
* gdb.server/server-kill.exp: Set breakpoint on line "i = 0;"
and continue to it. Read variable "server_pid".
This patch is to remove some lines which looks unnecessary. These
lines were added when server-kill.exp was added. In the version 1,
https://sourceware.org/ml/gdb-patches/2013-03/msg00691.html the test
calls runto_main and delete breakpoint on main,
+if ![runto_main] {
+ return -1
+}
+
+# Otherwise the breakpoint at 'main' would not cause insert
breakpoints during
+# first step.
+delete_breakpoints
However, in the version 2
https://sourceware.org/ml/gdb-patches/2013-03/msg00854.html runto_main
is removed but delete_breakpoints is still there. AFAICS, the line of
delete_breakpoints can be removed too.
gdb/testsuite:
2014-10-11 Yao Qi <yao@codesourcery.com>
* gdb.server/server-kill.exp: Remove "delete_breakpoints".
As the result of the patch below, GDB updates thread list when a stop is
presented to user. The tests don't have to fetch thread list explicitly.
[PATCH 3/3] Fix non-stop regressions caused by "breakpoints always-inserted off" changes
https://sourceware.org/ml/gdb-patches/2014-09/msg00734.html
This patch is to remove the test code updating thread list.
Run these three tests many times on arm-linux-gnueabi and x86-linux.
No regressions.
gdb/testsuite:
2014-10-11 Yao Qi <yao@codesourcery.com>
* gdb.threads/thread-find.exp: Don't execute command
"info threads".
* gdb.threads/attach-into-signal.exp (corefunc): Likewise.
* gdb.threads/linux-dp.exp: Don't check the condition
$threads_created equals to zero.
This does most of the mechanical removal. IOW, the easy part.
This doesn't touch procfs.c as that'd be a harder excision,
potentially affecting Solaris.
mips-tdep.c is left alone. E.g., I didn't delete the GDB_OSABI_IRIX
enum value, nor references to it in mips-tdep.c. Some comments
mentioning IRIX ABIs may still be relevant and I wouldn't know what to
do with them. in That can always be done on a separate pass,
preferably by someone who can test on MIPS.
I didn't remove a reference to IRIX in testsuite/lib/future.exp, as I
believe that code is imported from DejaGNU.
Built and tested on x86_64 Fedora 20, with --enable-targets=all.
Tested that building for --target=mips-sgi-irix6 on x86_64 Fedora 20
fails with:
checking for default auto-load directory... $debugdir:$datadir/auto-load
checking for default auto-load safe-path... $debugdir:$datadir/auto-load
*** Configuration mips-sgi-irix6 is obsolete.
*** Support has been REMOVED.
make[1]: *** [configure-gdb] Error 1
make[1]: Leaving directory `/home/pedro/gdb/mygit/build-irix'
make: *** [all] Error 2
gdb/
2014-10-10 Pedro Alves <palves@redhat.com>
* Makefile.in (ALL_TARGET_OBS): Remove mips-irix-tdep.o and solib-irix.o.
(ALLDEPFILES): Remove mips-irix-tdep.c and solib-irix.c.
(HFILES_NO_SRCDIR): Remove solib-irix.h.
* NEWS: Mention that support for mips-sgi-irix5* mips-sgi-irix6*
and been removed.
* config/mips/irix5.mh, config/mips/irix6.mh: Delete files.
* configure.ac: Remove references to IRIX.
* configure.host: Add *-*-irix* to the obsolete hosts section.
Remove all other references to irix.
* irix5-nat.c, mips-irix-tdep.c, solib-irix.c, solib-irix.h:
Delete files.
gdb/testsuite/
2014-10-10 Pedro Alves <palves@redhat.com>
* gdb.base/bigcore.exp: Remove references to IRIX.
* gdb.base/funcargs.exp: Likewise.
* gdb.base/interrupt.exp: Likewise.
* gdb.base/mips_pro.exp: Likewise.
* gdb.base/nodebug.exp: Likewise.
* gdb.base/setvar.exp: Likewise.
* lib/gdb.exp (gdb_compile_shlib): Remove mips-sgi-irix* case.
We currently validate the target description, but then forget to
reject it if found invalid.
Tested that incorrect descriptions are rejected and GDB warns about
them.
Tested the Microblaze Design with and without stack-protect registers.
The gdb command "info registers" displayed the register correctly. If
a stack protect design is not selected, only core registers are
displayed. When the stack-protect registers are selected in the
design, the core registers along with stack-protect registers are
displayed.
gdb/
2014-10-10 Ajit Agarwal <ajitkum@xilinx.com>
* microblaze-tdep.c (microblaze_gdbarch_init): If the description
isn't valid, release the tdesc arch data and return NULL.
We're now doing a vsyscall/vDSO address range lookup whenever we fetch
shared libraries, either through an explicit "info shared", or when
the target reports new libraries have been loaded, in order to filter
out the vDSO from glibc's DSO list. Before we started doing that, GDB
would only ever lookup the vsyscall's address range once in the
process's lifetime.
Looking up the vDSO address range requires an auxv lookup (which is
already cached, so no problem), but also reading the process's
mappings from /proc to find out the vDSO's mapping's size. That
generates extra RSP traffic when remote debugging. Particularly
annoying when the process's mappings grow linearly as more libraries
are mapped in, and we went through the trouble of making incremental
DSO list updates work against gdbserver (when the probes-based dynamic
linker interface is available).
The vsyscall/vDSO is mapped by the kernel when the process is
initially mapped in, and doesn't change throughout the process's
lifetime, so we can cache its address range.
Caching at this level brings GDB back to one and only one vsyscall
address range lookup per process.
Tested on x86_64 Fedora 20.
gdb/
2014-10-10 Pedro Alves <palves@redhat.com>
* linux-tdep.c: Include observer.h.
(linux_inferior_data): New global.
(struct linux_info): New structure.
(invalidate_linux_cache_inf, linux_inferior_data_cleanup)
(get_linux_inferior_data): New functions.
(linux_vsyscall_range): Rename to ...
(linux_vsyscall_range_raw): ... this.
(linux_vsyscall_range): New function; handles caching.
(_initialize_linux_tdep): Register linux_inferior_data. Install
inferior_exit and inferior_appeared observers.
With upstream glibc, GDB prints:
warning: Could not load shared library symbols for linux-vdso.so.1.
Do you need "set solib-search-path" or "set sysroot"?
A bug's been filed for glibc a few years back:
http://sourceware.org/bugzilla/show_bug.cgi?id=13097
but it's still not resolved. It's not clear whether there's even
consensus that this is indeed a glibc bug. It would actually be nice
if GDB also listed the vDSO in the shared library list, but there are
some design considerations with that:
- the vDSO is mapped by the kernel, not userspace, therefore we
should load its symbols right from the process's start of life,
even before glibc / the userspace loader sets up the initial DSO
list. The program might even be using a custom loader or no
loader.
- that kind of hints at that solib.c should handle retrieving shared
library lists from more than one source, and that symfile-mem.c's
loading of the vDSO would be converted to load and relocate the
vDSO's bfd behind the target_so_ops interface.
- and then, once glibc links in the vDSO to its DSO list, we'd need
to either:
a) somehow hand over the vDSO from one target_so_ops to the other
b) simply keep hiding glibc's entry.
And then b) seems the simplest.
With that in mind, this patch simply discards the vDSO from glibc's
reported shared library list.
We can match the vDSO address range with the addresses found iterating
the dynamic linker list, to tell which dynamic linker entry is the
vDSO.
Tested on x86_64 Fedora 20.
gdb/
2014-10-10 Jan Kratochvil <jan.kratochvil@redhat.com>
Pedro Alves <palves@redhat.com>
PR symtab/14466
* solib-svr4.c (svr4_read_so_list): Rename to ...
(svr4_current_sos_1): ... this and change the function comment.
(svr4_current_sos): New function.
gdb/testsuite/
2014-10-10 Jan Kratochvil <jan.kratochvil@redhat.com>
Pedro Alves <palves@redhat.com>
PR symtab/14466
* gdb.base/vdso-warning.c: New file.
* gdb.base/vdso-warning.exp: New file.
We have a case in solib-svr4.c where we could reuse symfile-mem.c's
vDSO range lookup. Since symfile-mem.c is not present in all
configurations solib-svr4.c is, move that lookup to a gdbarch hook.
This has the minor (good) side effect that we stop even trying the
target_auxv_search lookup against targets that don't have a concept of
a vDSO, in case symfile-mem.c happens to be linked in the build
(--enable-targets=all).
Tested on x86_64 Fedora 20.
gdb/
2014-10-10 Pedro Alves <palves@redhat.com>
* arch-utils.c (default_vsyscall_range): New function.
* arch-utils.h (default_vsyscall_range): New declaration.
* gdbarch.sh (vsyscall_range): New hook.
* gdbarch.h, gdbarch.c: Regenerate.
* linux-tdep.c (linux_vsyscall_range): New function.
(linux_init_abi): Install linux_vsyscall_range as
vsyscall_range gdbarch hook.
* memrange.c (address_in_mem_range): New function.
* memrange.h (address_in_mem_range): New declaration.
* symfile-mem.c (find_vdso_size): Delete function.
(add_vsyscall_page): Use gdbarch_vsyscall_range.
This patch fixes the bug described in PR tdep/9390, which is about a
wrong check in the following code:
...
/* optional copying of args in r2-r7 to r10-r13. */
/* Probably only in optimized case but legal action for prologue. */
else if ((inst & 0xff00) == 0x4600 /* 46SD mov rD, rS */
&& (inst & 0x00f0) >= 0x0020 && (inst & 0x00f0) <= 0x0070
&& (inst & 0x000f) >= 0x00a0 && (inst & 0x000f) <= 0x000d)
^^^^^^^^^^^^^^^^^^^^^^^^^
...
This condition will never trigger, and the fix proposed in the bug
(which made sense to me) was to test against 0x000a. I tried finding
documentation about this target, but couldn't find anything. I don't
even know if it is still used, but decided to submit the fix anyway.
Tested on my x86_64 Fedora 20 GNU/Linux.
gdb/ChangeLog:
2014-09-16 Sergio Durigan Junior <sergiodj@redhat.com>
PR tdep/9390
* xstorxstormy16-tdep.c (xstormy16_analyze_prologue): Fix possible
typo when using logical AND to determine instruction type.
As a result of commit b57bacec, local variable 'printed' is no longer
used. This patch is to remove it.
gdb:
2014-10-09 Yao Qi <yao@codesourcery.com>
* infrun.c (handle_signal_stop): Remove local variable 'printed'.
Add the relocation numbers defined in ABI release 1.0 but missing
from the current header. This will allow tools like objdump to dump
objects that use these relocations.
include/elf/ChangeLog:
2014-10-08 Will Newton <will.newton@linaro.org>
* aarch64.h: Sync up relocations with ABI release 1.0.
This commit makes fbsd-tdep.c not include string.h or gdb_assert.h
as both are already included by defs.h.
gdb/ChangeLog:
* fbsd-tdep.c: Do not include string.h or gdb_assert.h.
This commit includes common-exceptions.h in common-defs.h and removes
all other inclusions.
gdb/ChangeLog:
* common/common-defs.h: Include common-exceptions.h.
* exceptions.h: Do not include common-exceptions.h.
gdb/gdbserver/ChangeLog:
* server.h: Do not include common-exceptions.h.
This commit includes cleanups.h in common-defs.h and removes all other
inclusions.
gdb/ChangeLog:
* common/common-defs.h: Include cleanups.h.
* common/common-exceptions.c: Do not include cleanups.h.
* utils.h: Likewise.
gdb/gdbserver/ChangeLog:
* server.h: Do not include cleanups.h.
A helper function called `add_offset_16' is used by
`extended_mips16_next_pc' to calculate branch destinations. Weirdly
enough the helper does not do what the name suggests and rather than
doing its work for a 16-bit immediate branch offset it makes its
calculations on a 26-bit immediate target used by JAL and JALX
instructions. Furthermore the JAL/JALX calculation is only needed once
by `extended_mips16_next_pc' while a 16-bit branch offset calculation
is made inline several times across `extended_mips16_next_pc'.
This change therefore replaces the contents of `add_offset_16' with the
16-bit branch offset calculation and updates `extended_mips16_next_pc'
accordingly.
* mips-tdep.c (add_offset_16): Rewrite to implement what the
name implies.
(extended_mips16_next_pc): Update accordingly.
This change addresses a regression in gdb.dwarf2/dw2-skip-prologue.exp
across MIPS16 multilibs:
(gdb) file .../gdb.dwarf2/dw2-skip-prologue
Reading symbols from .../gdb.d/gdb.dwarf2/dw2-skip-prologue...done.
(gdb) delete breakpoints
(gdb) info breakpoints
No breakpoints or watchpoints.
(gdb) break main
warning: Breakpoint address adjusted from 0x00400725 to 0x00400721.
Breakpoint 1 at 0x400721
(gdb) set remotetimeout 5
(gdb) kill
The program is not being run.
(gdb)
[...]
target remote ...:2345
Reading symbols from .../mips16/lib/ld.so.1...done.
warning: Breakpoint address adjusted from 0x00400725 to 0x00400721.
warning: Breakpoint address adjusted from 0x00400725 to 0x00400721.
0x2aaa8e81 in __start () from .../mips16/lib/ld.so.1
(gdb) continue
Continuing.
warning: Breakpoint address adjusted from 0x00400725 to 0x00400721.
warning: Breakpoint 1 address previously adjusted from 0x00400725 to
0x00400721.
Breakpoint 1, 0x00400721 in main ()
(gdb) break func
Breakpoint 2 at 0x4006a1: func. (2 locations)
(gdb) continue
Continuing.
warning: GDB can't find the start of the function at 0x4006dd.
GDB is unable to find the start of the function at 0x4006dd
and thus can't determine the size of that function's stack frame.
This means that GDB may be unable to access that stack frame, or
the frames below it.
This problem is most likely caused by an invalid program counter or
stack pointer.
However, if you think GDB should simply search farther back
from 0x4006dd for code which looks like the beginning of a
function, you can increase the range of the search using the `set
heuristic-fence-post' command.
Program received signal SIGBUS, Bus error.
0x0040072b in main ()
(gdb) FAIL: gdb.dwarf2/dw2-skip-prologue.exp: continue to breakpoint: func
-- notice the breakpoint adjustment messages that are already a bad
sign. These happen when a breakpoint is requested in a branch delay
slot and are not supposed to happen unless explicitly requested with an
address pointing to a branch delay slot instruction. No symbol or line
debug information is supposed to direct GDB to place a breakpoint in a
delay slot.
Here's how `main' looks like:
00400718 <main>:
400718: 64f5 save 40,ra,s0-s1
40071a: 1a00 01a8 jal 4006a0 <func>
40071e: 0104 addiu s1,sp,16
400720: 1a00 01b7 jal 4006dc <func+0x3c>
400724: 6702 move s0,v0
400726: e049 addu v0,s0,v0
400728: 65b9 move sp,s1
40072a: 6473 restore 24,ra,s0-s1
40072c: e8a0 jrc ra
40072e: 6500 nop
-- so 0x400725 is the MIPS16 instruction address of the first MOVE
instruction seen above, in a delay slot of the preceding JAL instruction
indeed. This test case arranges for `main' to have no debug information
so it is one of the heuristic prologue scanners, `mips16_scan_prologue'
specifically in this case, that is responsible for finding the right
location for the breakpoint to place.
In this case the prologue really ends with the ADDIU instruction,
reordered into the delay slot of the first JAL instruction. Of course
we can't place the breakpoint for `main' after it as by doing so we'll
let `func' to be called before hitting this breakpoint. So the
breakpoint has to go at the JAL instruction instead, or 0x40071b.
To make a general case out of it we must never consider any jump or
branch instruction to be a part of a function's prologue. In the
presence of a jump or branch at the beginning of a function the furthest
instruction examined for the purpose of constructing frame information
can be one in the delay slot of that jump or branch if present, and
otherwise -- that is when the jump or branch is compact and has no delay
slot -- the instruction immediately preceding the jump or branch.
This change implements that approach across prologue scanners for the
three instruction ISAs. In implementing it I have factored out code
from the existing `*_instruction_has_delay_slot' handlers to be shared
and a side effect for the microMIPS implementation is it now always
fetches the second 16-bit halfword of 32-bit instructions even if it
eventually is not going to be needed. I think it's an acceptable
tradeoff for the purpose of code sharing.
To make things more consistent I also carried logic from
`micromips_scan_prologue' over to the other two scanners to accept (and
ignore) a single non-prologue non-control transfer instruction reordered
by the compiler into the prologue. While doing this I simplified the
exit path from the scan loop such that `end_prologue_addr' is set only
once. This made some concerns expressed in comments no longer
applicable, although even before they were not valid.
I have not fixed the logic around `load_immediate_bytes' in
`mips32_scan_prologue' though, it remains broken, although I took care
not to break it more. An approach similar to one taken for handling
larger stack adjustments in `micromips_scan_prologue' will have to be
eventually implemented here.
For regression testing I used my usual choice of the mips-linux-gnu
target and the following multilibs:
-EB
-EB -msoft-float
-EB -mips16
-EB -mips16 -msoft-float
-EB -mmicromips
-EB -mmicromips -msoft-float
-EB -mabi=n32
-EB -mabi=n32 -msoft-float
-EB -mabi=64
-EB -mabi=64 -msoft-float
and the -EL variants of same.
That removed gdb.dwarf2/dw2-skip-prologue.exp failures across MIPS16
multilibs, the test log now shows:
(gdb) file .../gdb.dwarf2/dw2-skip-prologue
Reading symbols from .../gdb.d/gdb.dwarf2/dw2-skip-prologue...done.
(gdb) delete breakpoints
(gdb) info breakpoints
No breakpoints or watchpoints.
(gdb) break main
Breakpoint 1 at 0x40071b
(gdb) set remotetimeout 5
(gdb) kill
The program is not being run.
(gdb)
[...]
target remote ...:2345
Reading symbols from .../mips16/lib/ld.so.1...done.
0x2aaa8e81 in __start () from .../mips16/lib/ld.so.1
(gdb) continue
Continuing.
Breakpoint 1, 0x0040071b in main ()
(gdb) break func
Breakpoint 2 at 0x4006a1: func. (2 locations)
(gdb) continue
Continuing.
Breakpoint 2, func (param=0) at main.c:5
5 This program is free software; you can redistribute it and/or modify
(gdb) PASS: gdb.dwarf2/dw2-skip-prologue.exp: continue to breakpoint: func
-- so things look like intended.
That also did regress, again across MIPS16 multilibs, another test case,
gdb.base/step-symless.exp:
(gdb) file .../gdb.d/gdb.base/step-symless
Reading symbols from .../gdb.base/step-symless...done.
(gdb) delete breakpoints
(gdb) info breakpoints
No breakpoints or watchpoints.
(gdb) break main
Breakpoint 1 at 0x4006d3
(gdb) set remotetimeout 5
(gdb) kill
The program is not being run.
(gdb)
[...]
target remote ...:2345
Reading symbols from .../mips16/lib/ld.so.1...done.
0x2aaa8e81 in __start () from .../mips16/lib/ld.so.1
(gdb) continue
Continuing.
Breakpoint 1, 0x004006d3 in main ()
(gdb) break symful
Breakpoint 2 at 0x4006a5
(gdb) step
Single stepping until exit from function main,
which has no line number information.
warning: GDB can't find the start of the function at 0x4006b9.
GDB is unable to find the start of the function at 0x4006b9
and thus can't determine the size of that function's stack frame.
This means that GDB may be unable to access that stack frame, or
the frames below it.
This problem is most likely caused by an invalid program counter or
stack pointer.
However, if you think GDB should simply search farther back
from 0x4006b9 for code which looks like the beginning of a
function, you can increase the range of the search using the `set
heuristic-fence-post' command.
0x004006b9 in ?? ()
(gdb) FAIL: gdb.base/step-symless.exp: step
-- but that is actually a good sign. Here `main', again, has no debug
information and code involved looks like:
004006a0 <symful>:
4006a0: 6491 save 8,s1
4006a2: 673d move s1,sp
4006a4: b204 lw v0,4006b4 <symful+0x14>
4006a6: 9a40 lw v0,0(v0)
4006a8: 4261 addiu v1,v0,1
4006aa: b203 lw v0,4006b4 <symful+0x14>
4006ac: da60 sw v1,0(v0)
4006ae: 65b9 move sp,s1
4006b0: 6411 restore 8,s1
4006b2: e8a0 jrc ra
4006b4: 0041 addiu s0,sp,260
4006b6: 0860 la s0,400834 <__libc_start_main@mips16plt+0x54>
4006b8: 6491 save 8,s1
4006ba: 673d move s1,sp
4006bc: b204 lw v0,4006cc <symful+0x2c>
4006be: 9a40 lw v0,0(v0)
4006c0: 4261 addiu v1,v0,1
4006c2: b203 lw v0,4006cc <symful+0x2c>
4006c4: da60 sw v1,0(v0)
4006c6: 65b9 move sp,s1
4006c8: 6411 restore 8,s1
4006ca: e8a0 jrc ra
4006cc: 0041 addiu s0,sp,260
4006ce: 0860 la s0,40084c <__libc_start_main@mips16plt+0x6c>
004006d0 <main>:
4006d0: 64d4 save 32,ra,s1
4006d2: 1a00 01ae jal 4006b8 <symful+0x18>
4006d6: 0104 addiu s1,sp,16
4006d8: 1a00 01a8 jal 4006a0 <symful>
4006dc: 6500 nop
4006de: 6740 move v0,zero
4006e0: 65b9 move sp,s1
4006e2: 6452 restore 16,ra,s1
4006e4: e8a0 jrc ra
4006e6: 6500 nop
4006e8: 6500 nop
4006ea: 6500 nop
4006ec: 6500 nop
4006ee: 6500 nop
-- and the original log:
(gdb) file .../gdb.base/step-symless
Reading symbols from .../gdb.base/step-symless...done.
(gdb) delete breakpoints
(gdb) info breakpoints
No breakpoints or watchpoints.
(gdb) break main
warning: Breakpoint address adjusted from 0x004006dd to 0x004006d9.
Breakpoint 1 at 0x4006d9
(gdb) set remotetimeout 5
(gdb) kill
The program is not being run.
(gdb)
[...]
target remote ...:2345
Reading symbols from .../mips16/lib/ld.so.1...done.
warning: Breakpoint address adjusted from 0x004006dd to 0x004006d9.
warning: Breakpoint address adjusted from 0x004006dd to 0x004006d9.
0x2aaa8e81 in __start () from .../mips16/lib/ld.so.1
(gdb) continue
Continuing.
warning: Breakpoint address adjusted from 0x004006dd to 0x004006d9.
warning: Breakpoint 1 address previously adjusted from 0x004006dd to
0x004006d9.
Breakpoint 1, 0x004006d9 in main ()
(gdb) break symful
Breakpoint 2 at 0x4006a5
(gdb) step
Single stepping until exit from function main,
which has no line number information.
Breakpoint 2, 0x004006a5 in symful ()
(gdb) PASS: gdb.base/step-symless.exp: step
So the breakpoint at `main' was actually set at an instruction after the
call to `symful+0x18' aka `symless' and the test only passed because
single-stepping through `symless' wasn't actually done at all. With
this change in place this test fails for MIPS16 multilibs consistently
with all the other multilibs where it already failed in this manner
previously.
* mips-tdep.c (mips16_instruction_is_compact_branch): New
function.
(micromips_instruction_is_compact_branch): Likewise.
(mips16_scan_prologue): Terminate scanning upon seeing a branch
or a compact jump, reaching a jump delay slot, or seeing a
second non-prologue instruction.
(micromips_scan_prologue): Also terminate scanning upon seeing a
compact branch or jump, or reaching a branch or jump delay slot.
(mips32_scan_prologue): Terminate scanning upon reaching a branch
or jump delay slot, or seeing a second non-prologue instruction.
(mips32_instruction_has_delay_slot): Retain instruction
examination code only, update arguments accordingly and move
instruction fetch pieces to...
(mips32_insn_at_pc_has_delay_slot): ... this new function.
(micromips_instruction_has_delay_slot): Likewise and to...
(micromips_insn_at_pc_has_delay_slot): ... this new function.
(mips16_instruction_has_delay_slot): Likewise and to...
(mips16_insn_at_pc_has_delay_slot): ... this new function.
(mips_single_step_through_delay): Update accordingly.
(mips_adjust_breakpoint_address): Likewise.
This change addresses `micromips_instruction_has_delay_slot' and
`mips16_instruction_has_delay_slot' that both incorrectly interpret
their MUSTBE32 argument. Their callers assume that when the flag is
clear these functions will return 1 when any non-compact jump or branch
instruction is present at ADDR, while in fact they will only return 1
for 16-bit such instructions only. This change makes the implementation
match the expectations.
* mips-tdep.c (micromips_instruction_has_delay_slot): When
!mustbe32 also return 1 for 32-bit instructions.
(mips16_instruction_has_delay_slot): Likewise. Add an
explanatory comment.
These are useless because they can't match any address. In fact,
worse than useless because the .eh_frame_hdr lookup table matching
addresses to FDEs does not contain information about the FDE range.
The table is sorted by address; Range is inferred by the address
delta from one entry to the next. So if a zero address range FDE is
followed by a normal non-zero range FDE for the same address,
everything is good. However, the qsort could just as easily sort the
FDEs in the other order, in which case the normal FDE would
effectively be seen to have a zero range.
bfd/
PR 17447
* elf-bfd.h (struct eh_cie_fde): Comment re NULL u.fde.cie_inf.
* elf-eh-frame.c (_bfd_elf_parse_eh_frame): Mark zero address
range FDEs for discarding.
(vma_compare): Sort on range after address.
(_bfd_elf_gc_mark_fdes): Test for NULL u.fde.cie_inf.
(_bfd_elf_discard_section_eh_frame): Likewise. Write "FDE" in
error message rather than "fde".
(_bfd_elf_write_section_eh_frame_hdr): Write "PC" and "FDE" in
error message.
ld/testsuite/
* ld-elf/eh1.s: Don't create FDEs with zero address ranges.
* ld-elf/eh3.s: Likewise.
* ld-elf/eh1.d, * ld-elf/eh2.d, * ld-elf/eh3.d: Adjust.
* ld-mips-elf/eh-frame1-n32.d: Warning match update.
* ld-mips-elf/eh-frame1-n64.d: Likewise.
* ld-mips-elf/eh-frame2-n32.d: Likewise.
* ld-mips-elf/eh-frame2-n64.d: Likewise.
This patch was committed to GCC trunk as revision 215865.
2014-10-03 Jing Yu <jingyu@google.com>
* configure.ac: Add aarch64 to list of targets that support gold.
* configure: Regenerate.
In installing minimal symbols for ELF shared library trampolines
we "forget" to make individual symbols special where required. This
leads to problems on the MIPS target using microMIPS SVR4 lazy stubs.
Lacking the special annotation these stubs are treated as standard
MIPS code and this makes GDB insert the wrong software breakpoint
instruction, breaking e.g. single-stepping through these stubs. This
is not a very frequent scenario as microMIPS SVR4 lazy stubs are
typically only used in shared libraries with the main executable
using PLT, handled elsewhere. Still it triggers e.g. when a software
watchpoint has been installed. The symptom is SIGILL or the program
going astray, depending on the endianness. Disassembly of these stubs
is also wrong.
* elfread.c (elf_symtab_read): Also mark solib trampoline minimal
symbols special.
This change:
commit b775012e84
Author: Luis Machado <luisgpm@br.ibm.com>
Date: Fri Feb 24 15:10:59 2012 +0000
2012-02-24 Luis Machado <lgustavo@codesourcery.com>
* remote.c (remote_supports_cond_breakpoints): New forward
declaration.
[...]
changed the way breakpoints are inserted and removed such that
`insert_bp_location' can now be called with the breakpoint being handled
already in place, while previously the call was only ever made for
breakpoints that have not been put in place. This in turn caused an
issue for software breakpoints and targets for which a breakpoint's
`placed_address' may not be the same as the original requested address.
The issue is `insert_bp_location' overwrites the previously adjusted
value in `placed_address' with the original address, that is only
replaced back with the correct adjusted address later on when
`gdbarch_breakpoint_from_pc' is called. Meanwhile there's a window
where the value in `placed_address' does not correspond to data stored
in `shadow_contents', leading to incorrect instruction bytes being
supplied when `one_breakpoint_xfer_memory' is called to supply the
instruction overlaid by the breakpoint.
And this is exactly what happens on the MIPS target with software
breakpoints placed in microMIPS code. In this case not only
`placed_address' is not the original address because of the ISA bit, but
`mips_breakpoint_from_pc' has to read the original instruction to
determine which one of the two software breakpoint instruction encodings
to choose as well. The 16-bit encoding is used to replace 16-bit
instructions and similarly the 32-bit one is used with 32-bit
instructions, to satisfy branch delay slot size requirements.
The mismatch between `placed_address' and the address data in
`shadow_contents' has been obtained from leads to the wrong encoding
being used in some cases, which in the case of a 32-bit software
breakpoint instruction replacing a 16-bit instruction causes corruption
to the adjacent following instruction and leads the debug session astray
if execution reaches there e.g. with a jump.
To address this problem I made the change below, that adds a
`reqstd_address' field to `struct bp_target_info' and leaves
`placed_address' unchanged once it has been set. This ensures data in
`shadow_contents' is always consistent with `placed_address'.
This approach also has this good side effect that all the places that
examine the breakpoint's address see a consistent value, either
`reqstd_address' or `placed_address', as required. Currently some
places see either the original or the adjusted address in
`placed_address', depending on whether they have been called before
`gdbarch_remote_breakpoint_from_pc' or afterwards. This is in
particular true for subsequent calls to
`gdbarch_remote_breakpoint_from_pc' itself, e.g. from
`one_breakpoint_xfer_memory'. This is also important for places like
`find_single_step_breakpoint' where a breakpoint's address is compared
to the raw value of $pc.
* breakpoint.h (bp_target_info): Add `reqstd_address' member,
update comments.
* breakpoint.c (one_breakpoint_xfer_memory): Use `reqstd_address'
for the breakpoint's address. Don't preinitialize `placed_size'.
(insert_bp_location): Set `reqstd_address' rather than
`placed_address'.
(bp_target_info_copy_insertion_state): Also copy `placed_address'.
(bkpt_insert_location): Use `reqstd_address' for the breakpoint's
address.
(bkpt_remove_location): Likewise.
(deprecated_insert_raw_breakpoint): Likewise.
(deprecated_remove_raw_breakpoint): Likewise.
(find_single_step_breakpoint): Likewise.
* mem-break.c (default_memory_insert_breakpoint): Use
`reqstd_address' for the breakpoint's address. Don't set
`placed_address' or `placed_size' if breakpoint contents couldn't
have been determined.
* remote.c (remote_insert_breakpoint): Use `reqstd_address' for
the breakpoint's address.
(remote_insert_hw_breakpoint): Likewise. Don't set
`placed_address' or `placed_size' if breakpoint couldn't have been
set.
* aarch64-linux-nat.c (aarch64_linux_insert_hw_breakpoint): Use
`reqstd_address' for the breakpoint's address.
* arm-linux-nat.c (arm_linux_hw_breakpoint_initialize): Likewise.
* ia64-tdep.c (ia64_memory_insert_breakpoint): Likewise.
* m32r-tdep.c (m32r_memory_insert_breakpoint): Likewise.
* microblaze-linux-tdep.c
(microblaze_linux_memory_remove_breakpoint): Likewise.
* monitor.c (monitor_insert_breakpoint): Likewise.
* nto-procfs.c (procfs_insert_breakpoint): Likewise.
(procfs_insert_hw_breakpoint): Likewise.
* ppc-linux-nat.c (ppc_linux_insert_hw_breakpoint): Likewise.
* ppc-linux-tdep.c (ppc_linux_memory_remove_breakpoint): Likewise.
* remote-m32r-sdi.c (m32r_insert_breakpoint): Likewise.
* remote-mips.c (mips_insert_breakpoint): Likewise.
* x86-nat.c (x86_insert_hw_breakpoint): Likewise.
On MIPS64 little endian, attempting an assignment to a bit field
that lives in a register yields the wrong result. It just corrupts
the data in the register depending on the specific position of the
bit field inside the structure.
FAIL: gdb.base/store.exp: f_1.j
FAIL: gdb.base/store.exp: f_1.k
FAIL: gdb.base/store.exp: F_1.i
FAIL: gdb.base/store.exp: F_1.j
FAIL: gdb.base/store.exp: F_1.k
FAIL: gdb.base/store.exp: f_2.j
FAIL: gdb.base/store.exp: f_2.k
FAIL: gdb.base/store.exp: F_2.i
FAIL: gdb.base/store.exp: F_2.j
FAIL: gdb.base/store.exp: F_2.k
FAIL: gdb.base/store.exp: f_3.j
FAIL: gdb.base/store.exp: f_3.k
FAIL: gdb.base/store.exp: F_3.i
FAIL: gdb.base/store.exp: F_3.j
FAIL: gdb.base/store.exp: F_3.k
FAIL: gdb.base/store.exp: f_4.j
FAIL: gdb.base/store.exp: f_4.k
FAIL: gdb.base/store.exp: F_4.i
FAIL: gdb.base/store.exp: F_4.j
FAIL: gdb.base/store.exp: F_4.k
=== gdb Summary ===
Now, GDB knows how to do bit field assignment properly, but MIPS is
one of those architectures that uses a hook for the register-to-value
conversion. Although we can properly tell when the type being passed
is a structure or union, we cannot tell when it is a bit field,
because the bit field data lives in a value structure. Such data
only lives in a "type" structure when the parent structure is being
referenced, thus you can collect them from the flds_bnds members.
A bit field type structure looks pretty much the same as any other
primitive type like int or char, so we can't distinguish them.
Forcing more fields into the type structure wouldn't help much,
because the type structs are shared.
2014-10-03 Luis Machado <lgustavo@codesourcery.com>
* valops.c (value_assign): Check for bit field assignments
before calling architecture-specific register value
conversion functions.
Trying to debug gdb with itself,
I stumbled on the following complaints
Unknown symbol type 0x2e
or
Unknown symbol type 0x4e
It appears that those corrspond to N_BNSYM and N_ENSYM,
which are MacOS extensions of stabs debugging format.
But these extensions have been used inside gcc probalby
for a while already, see:
https://gcc.gnu.org/ml/gcc/2004-08/msg00157.html
As the only purpose of these entries is to allow for removal
of stabs information if the function is removed,
it can be safely ignored by GDB.
This patch simply adds those two entry types to the list
of ignored entry type in read_dbx_symtab function.
Is this OK?
Pierre Muller
2014-10-03 Pierre Muller <muller@sourceware.org>
* dbxread.c (read_dbx_symtab): Also ignore N_BNSYM/N_ENSYM.
In git b57bacec, I said:
> With that in place, the need to delay "Program received signal FOO"
> was actually caught by the manythreads.exp test. Without that bit, I
> was getting:
>
> [Thread 0x7ffff7f13700 (LWP 4499) exited]
> [New Thread 0x7ffff7f0b700 (LWP 4500)]
> ^C
> Program received signal SIGINT, Interrupt.
> [New Thread 0x7ffff7f03700 (LWP 4501)] <<< new output
> [Switching to Thread 0x7ffff7f0b700 (LWP 4500)]
> __GI___nptl_death_event () at events.c:31
> 31 {
> (gdb) FAIL: gdb.threads/manythreads.exp: stop threads 1
>
> That is, I was now getting "New Thread" lines after the "Program
> received signal" line, and the test doesn't expect them. As the
> number of new threads discovered before and after the "Program
> received signal" output is unbounded, it's much nicer to defer
> "Program received signal" until after synching the thread list, thus
> close to the "switching to thread" output and "current frame/source"
> info:
>
> [Thread 0x7ffff7863700 (LWP 7647) exited]
> ^C[New Thread 0x7ffff786b700 (LWP 7648)]
>
> Program received signal SIGINT, Interrupt.
> [Switching to Thread 0x7ffff7fc4740 (LWP 6243)]
> __GI___nptl_create_event () at events.c:25
> 25 {
> (gdb) PASS: gdb.threads/manythreads.exp: stop threads 1
This commit factors out the two places in the test that are effected
by this, and adds there a destilled version of the comment above.
gdb/testsuite/
2014-10-02 Pedro Alves <palves@redhat.com>
* gdb.threads/manythreads.exp (interrupt_and_wait): New procedure.
(top level) <stop threads 1, stop threads 2>: Use it.
Commit a25a5a45 (Fix "breakpoint always-inserted off"; remove
"breakpoint always-inserted auto") regressed non-stop remote
debugging.
This was exposed by mi-nsintrall.exp intermittently failing with a
spurious SIGTRAP.
The problem is that when debugging with "target remote", new threads
the target has spawned but have never reported a stop aren't visible
to GDB until it explicitly resyncs its thread list with the target's.
For example, in a program like this:
int
main (void)
{
pthread_t child_thread;
pthread_create (&child_thread, NULL, child_function, NULL);
return 0; <<<< set breakpoint here
}
If the user sets a breakpoint at the "return" statement, and runs the
program, when that breakpoint hit is reported, GDB is only aware of
the main thread. So if we base the decision to remove or insert
breakpoints from the target based on whether all the threads we know
about are stopped, we'll miss that child_thread is running, and thus
we'll remove breakpoints from the target, even through they should
still remain inserted, otherwise child_thread will miss them.
The break-while-running.exp test actually should also be exposing this
thread-list-out-of-synch problem. That test sets a breakpoint while
the main thread is stopped, but other threads are running. Because
other threads are running, the breakpoint is supposed to be inserted
immediately. But, unless something forces a refetch of the thread
list, like, e.g., "info threads", GDB won't be aware of the other
threads that had been spawned by the main thread, and so won't insert
new or old breakpoints in the target. And it turns out that the test
is exactly doing an explicit "info threads", masking out the
problem... This commit adjust the test to exercise the case of not
issuing "info threads". The test then fails without the GDB fix.
In the ni-nsintrall.exp case, what happens is that several threads hit
the same breakpoint, and when the first thread reports the stop,
because GDB wasn't aware other threads exist, all threads known to GDB
are found stopped, so GDB removes the breakpoints from the target.
The other threads follow up with SIGTRAPs too for that same
breakpoint, which has already been removed. For the first few
threads, the moribund breakpoints machinery suppresses the SIGTRAPs,
but after a few events (precisely '3 * thread_count () + 1' at the
time the breakpoint was removed, see update_global_location_list), the
moribund breakpoint machinery is no longer aware of the removed
breakpoint, and the SIGTRAP is reported as a spurious stop.
The fix is naturally then to stop assuming that if no thread in the
list is executing, then the target is fully stopped. We can't know
that until we fully sync the thread list. Because updating the thread
list on every stop would be too much RSP traffic, I chose instead to
update it whenever we're about to present a stop to the user.
Actually updating the thread list at that point happens to be an item
I had added to the local/remote parity wiki page a while ago:
Native GNU/Linux debugging adds new threads to the thread list as
the program creates them "The [New Thread foo] messages". Remote
debugging can't do that, and it's arguable whether we shouldn't even
stop native debugging from doing that, as it hinders inferior
performance. However, a related issue is that with remote targets
(and gdbserver), even after the program stops, the user still needs
to do "info threads" to pull an updated thread list. This, should
most likely be addressed, so that GDB pulls the list itself, perhaps
just before presenting a stop to the user.
With that in place, the need to delay "Program received signal FOO"
was actually caught by the manythreads.exp test. Without that bit, I
was getting:
[Thread 0x7ffff7f13700 (LWP 4499) exited]
[New Thread 0x7ffff7f0b700 (LWP 4500)]
^C
Program received signal SIGINT, Interrupt.
[New Thread 0x7ffff7f03700 (LWP 4501)] <<< new output
[Switching to Thread 0x7ffff7f0b700 (LWP 4500)]
__GI___nptl_death_event () at events.c:31
31 {
(gdb) FAIL: gdb.threads/manythreads.exp: stop threads 1
That is, I was now getting "New Thread" lines after the "Program
received signal" line, and the test doesn't expect them. As the
number of new threads discovered before and after the "Program
received signal" output is unbounded, it's much nicer to defer
"Program received signal" until after synching the thread list, thus
close to the "switching to thread" output and "current frame/source"
info:
[Thread 0x7ffff7863700 (LWP 7647) exited]
^C[New Thread 0x7ffff786b700 (LWP 7648)]
Program received signal SIGINT, Interrupt.
[Switching to Thread 0x7ffff7fc4740 (LWP 6243)]
__GI___nptl_create_event () at events.c:25
25 {
(gdb) PASS: gdb.threads/manythreads.exp: stop threads 1
Tested on x86_64 Fedora 20, native and gdbserver.
gdb/
2014-10-02 Pedro Alves <palves@redhat.com>
* breakpoint.c (breakpoints_should_be_inserted_now): Use
threads_are_executing.
* breakpoint.h (breakpoints_should_be_inserted_now): Add
describing comment.
* gdbthread.h (threads_are_executing): Declare.
(handle_signal_stop) <random signals>: Don't print about the
signal here if stopping.
(end_stepping_range): Don't notify observers here.
(normal_stop): Update the thread list. If stopped by a random
signal or a stepping range ended, notify observers.
* thread.c (threads_executing): New global.
(init_thread_list): Clear 'threads_executing'.
(set_executing): Set or clear 'threads_executing'.
(threads_are_executing): New function.
(update_threads_executing): New function.
(update_thread_list): Use it.
gdb/testsuite/
2014-10-02 Pedro Alves <palves@redhat.com>
* gdb.threads/break-while-running.exp (test): Add new
'update_thread_list' argument. Skip "info threads" if false.
(top level): Add new 'update_thread_list' axis.
Following an exec with "breakpoint always-inserted on" tries to insert
breakpoints in the new image at the addresses the symbols had in the
old image.
With "always-inserted off", we see:
gdb gdb.multi/multi-arch-exec -ex "set breakpoint always-inserted off"
GNU gdb (GDB) 7.8.50.20140924-cvs
...
(gdb) b main
Breakpoint 1 at 0x400664: file gdb.multi/multi-arch-exec.c, line 24.
^^^^^^^^
(gdb) c
The program is not being run.
(gdb) r
Starting program: testsuite/gdb.multi/multi-arch-exec
Breakpoint 1, main () at gdb/testsuite/gdb.multi/multi-arch-exec.c:24
24 execl (BASEDIR "/multi-arch-exec-hello",
(gdb) c
Continuing.
process 9212 is executing new program: gdb/testsuite/gdb.multi/multi-arch-exec-hello
Breakpoint 1, main () at gdb/testsuite/gdb.multi/hello.c:40
40 bar();
(gdb) info breakpoints
Num Type Disp Enb Address What
1 breakpoint keep y 0x080484e4 in main at gdb/testsuite/gdb.multi/hello.c:40
^^^^^^^^^^
breakpoint already hit 2 times
(gdb)
Note how main was 0x400664 in multi-arch-exec, and 0x080484e4 in
gdb.multi/hello.
With "always-inserted on", we get:
Breakpoint 1, main () at gdb/testsuite/gdb.multi/multi-arch-exec.c:24
24 execl (BASEDIR "/multi-arch-exec-hello",
(gdb) c
Continuing.
infrun: target_wait (-1, status) =
infrun: 9444 [process 9444],
infrun: status->kind = execd
infrun: infwait_normal_state
infrun: TARGET_WAITKIND_EXECD
Warning:
Cannot insert breakpoint 1.
Cannot access memory at address 0x400664
(gdb)
That is, GDB is trying to insert a breakpoint at 0x400664, after the
exec, and then that address happens to not be mapped at all in the new
image.
The problem is that update_breakpoints_after_exec is creating
breakpoints, which ends up in update_global_location_list immediately
inserting breakpoints if "breakpoints always-inserted" is "on".
update_breakpoints_after_exec is called very early when we see an exec
event. At that point, we haven't loaded the symbols of the new
post-exec image yet, and thus haven't reset breakpoint's addresses to
whatever they may be in the new image. All we should be doing in
update_breakpoints_after_exec is deleting breakpoints that no longer
make sense after an exec. So the fix removes those breakpoint
creations.
The question is then, if not here, where are those breakpoints
re-created? Turns out we don't need to do anything else, because at
the end of follow_exec, we call breakpoint_re_set, whose tail is also
creating exactly the same breakpoints update_breakpoints_after_exec is
currently creating:
breakpoint_re_set (void)
{
...
create_overlay_event_breakpoint ();
create_longjmp_master_breakpoint ();
create_std_terminate_master_breakpoint ();
create_exception_master_breakpoint ();
}
A new test is added to exercise this.
Tested on x86_64 Fedora 20.
gdb/
2014-10-02 Pedro Alves <palves@redhat.com>
PR breakpoints/17431
* breakpoint.c (update_breakpoints_after_exec): Don't create
overlay, longjmp, std terminate nor exception breakpoints here.
gdb/testsuite/
2014-10-02 Pedro Alves <palves@redhat.com>
PR breakpoints/17431
* gdb.base/execl-update-breakpoints.c: New file.
* gdb.base/execl-update-breakpoints.exp: New file.
A patch I wrote made GDB pull the thread list sooner when debugging
with target remote, and I noticed an intended consequence. GDB
started bouncing around the currently selected remote/general thread
more frequently. E.g.:
Sending packet: $qTMinFTPILen#3b...Packet received: 5
+Sending packet: $Hgp726d.726d#53...Packet received: OK
Sending packet: $m400680,40#2f...Packet received: 85c0741455bff00d60004889e5ffd05de97bffffff0f1f00e973ffffff0f1f00554889e5c745fc00000000c745fc01000000e900000000c745fc02000000b800
+Sending packet: $Hgp726d.7278#28...Packet received: OK
Sending packet: $m4006b2,1#28...Packet received: e9
Fast tracepoint 2 at 0x4006b2: file gdb/testsuite/gdb.trace/range-stepping.c, line 53.
Sending packet: $qTStatus#49...Packet received: T0;tnotrun:0;tframes:0;tcreated:0;tfree:500000;tsize:500000;circular:0;disconn:0;starttime:0;stoptime:0;username:;notes::
This ended up breaking "tstart" when one has fast tracepoints set,
because gdbserver isn't expecting an Hg packet in response to
qRelocInsn:
(gdb) ftrace *set_point
Fast tracepoint 3 at 0x4006b2: file gdb/testsuite/gdb.trace/range-stepping.c, line 53.
(gdb) PASS: gdb.trace/range-stepping.exp: ftrace: ftrace *set_point
tstart
gdbserver: Malformed response to qRelocInsn, ignoring: Hgp2783.2783
Target does not support this command.
(gdb) FAIL: gdb.trace/range-stepping.exp: ftrace: tstart
remote_trace_start should probably start by making sure the remote
current thread matches inferior_ptid (calling set_general_thread), but
still, reducing unnecessary bouncing is a good idea. It happens
because the memory/symbol/breakpoint routines use
switch_to_program_space_and_thread to do something in the right
context and then revert back to the previously current thread.
The fix is to simply make any_thread_of_process,
find_inferior_for_program_space, etc. give preference to the current
thread/inferior it if matches.
gdb/
2014-10-02 Pedro Alves <palves@redhat.com>
* gdbthread.h (any_thread_of_process, any_live_thread_of_process):
Adjust comments.
* inferior.c (find_inferior_for_program_space): Give preference to
the current inferior.
* inferior.h (find_inferior_for_program_space): Update comment.
* progspace.c (switch_to_program_space_and_thread): Prefer the
current inferior if it's bound to the program space requested. If
the inferior found doesn't have a PID yet, don't bother looking up
a thread.
* progspace.h (switch_to_program_space_and_thread): Adjust
comment.
* thread.c (any_thread_of_process, any_live_thread_of_process):
Give preference to the current thread.
Currently, with "set breakpoint auto-hw off", we'll still try to
insert a software breakpoint at addresses covered by supposedly
read-only or inacessible regions:
(top-gdb) mem 0x443000 0x450000 ro
(top-gdb) set mem inaccessible-by-default off
(top-gdb) disassemble
Dump of assembler code for function main:
0x0000000000443956 <+34>: movq $0x0,0x10(%rax)
=> 0x000000000044395e <+42>: movq $0x0,0x18(%rax)
0x0000000000443966 <+50>: mov -0x24(%rbp),%eax
0x0000000000443969 <+53>: mov %eax,-0x20(%rbp)
End of assembler dump.
(top-gdb) b *0x0000000000443969
Breakpoint 5 at 0x443969: file ../../src/gdb/gdb.c, line 29.
(top-gdb) c
Continuing.
warning: cannot set software breakpoint at readonly address 0x443969
Breakpoint 5, 0x0000000000443969 in main (argc=1, argv=0x7fffffffd918) at ../../src/gdb/gdb.c:29
29 args.argc = argc;
(top-gdb)
We warn, saying that the insertion can't be done, but then proceed
attempting the insertion anyway, and in case of manually added
regions, the insert actually succeeds.
This is a regression; GDB used to fail inserting the breakpoint. More
below.
I stumbled on this as I wrote a test that manually sets up a read-only
memory region with the "mem" command, in order to test GDB's behavior
with breakpoints set on read-only regions, even when the real memory
the breakpoints are set at isn't really read-only. I wanted that in
order to add a test that exercises software single-stepping through
read-only regions.
Note that the memory regions that target_memory_map returns aren't
like e.g., what would expect to see in /proc/PID/maps on Linux.
Instead, they're the physical memory map from the _debuggers_
perspective. E.g., a read-only region would be real ROM or flash
memory, while a read-only+execute mapping in /proc/PID/maps is still
read-write to the debugger (otherwise the debugger wouldn't be able to
set software breakpoints in the code segment).
If one tries to manually write to memory that falls within a memory
region that is known to be read-only, with e.g., "p foo = 1", then we
hit a check in memory_xfer_partial_1 before the write mananges to make
it to the target side.
But writing a software/memory breakpoint nowadays goes through
target_write_raw_memory, and unlike when writing memory with
TARGET_OBJECT_MEMORY, nothing on the TARGET_OBJECT_RAW_MEMORY path
checks whether we're trying to write to a read-only region.
At the time "breakpoint auto-hw" was added, we didn't have the
TARGET_OBJECT_MEMORY vs TARGET_OBJECT_RAW_MEMORY target object
distinction yet, and the code path in memory_xfer_partial that blocks
writes to read-only memory was hit for memory breakpoints too. With
GDB 6.8 we had:
warning: cannot set software breakpoint at readonly address 0000000000443943
Warning:
Cannot insert breakpoint 1.
Error accessing memory address 0x443943: Input/output error.
So I started out by fixing this by adding the memory region validation
to TARGET_OBJECT_RAW_MEMORY too.
But later, when testing against GDBserver, I realized that that would
only block software/memory breakpoints GDB itself inserts with
gdb/mem-break.c. If a target has a to_insert_breakpoint method, the
insertion request will still pass through to the target. So I ended
up converting the "cannot set breakpoint" warning in breakpoint.c to a
real error return, thus blocking the insertion sooner.
With that, we'll end up no longer needing the TARGET_OBJECT_RAW_MEMORY
changes once software single-step breakpoints are converted to real
breakpoints. We need them today as software single-step breakpoints
bypass insert_bp_location. But, it'll be best to leave that in as
safeguard anyway, for other direct uses of TARGET_OBJECT_RAW_MEMORY.
Tested on x86_64 Fedora 20, native and gdbserver.
gdb/
2014-10-01 Pedro Alves <palves@redhat.com>
* breakpoint.c (insert_bp_location): Error out if inserting a
software breakpoint at a read-only address.
* target.c (memory_xfer_check_region): New function, factored out
from ...
(memory_xfer_partial_1): ... this. Make the 'reg_len' local a
ULONGEST.
(target_xfer_partial) <TARGET_OBJECT_RAW_MEMORY>: Check the access
against the memory region attributes.
gdb/testsuite/
2014-10-01 Pedro Alves <palves@redhat.com>
* gdb.base/breakpoint-in-ro-region.c: New file.
* gdb.base/breakpoint-in-ro-region.exp: New file.
Don't reset the exit code at inferior exit and print it in
-list-thread-groups.
gdb/ChangeLog:
* NEWS: Announce new exit-code field in -list-thread-groups
output.
* inferior.c (exit_inferior_1): Don't clear exit code.
(inferior_appeared): Clear exit code.
* mi/mi-main.c (print_one_inferior): Add printing of the exit
code.
gdb/testsuite/ChangeLog:
* gdb.mi/mi-exit-code.exp: New file.
* gdb.mi/mi-exit-code.c: New file.
gdb/doc/ChangeLog:
* gdb.texinfo (Miscellaneous gdb/mi Commands): Document new
exit-code field in -list-thread-groups output.
This makes it easier to rebuild all GDB's generated target description
C files.
It also clarifies the comments a bit. One might think we need a GDB
configured for the particular arquitecture (--target=foo). But a
build that includes support for the target description is sufficient.
(GDB rejects target descriptions that explicitly specify the
architecture, with an <architecture> element, if the architecture is
unknown.)
Tested that "make clean-cfiles" deletes all .c files under
src/gdb/features/, and that "make cfiles" generates them all without
error, and that diffing the newly generated C files against master
comes out an empty diff.
gdb/
2014-10-01 Pedro Alves <palves@redhat.com>
* features/Makefile: Update comments.
(XMLTOC): List all xml files we build C files from.
(clean-cfiles): New rule.
I regenerated all the .c files under src/gdb/features/ and this is
what I got.
gdb/
2014-10-01 Pedro Alves <palves@redhat.com>
* features/i386/amd64-avx512-linux.c: Regenerate.
* features/i386/amd64-avx512.c: Regenerate.
* features/i386/x32-avx512-linux.c: Regenerate.
* features/i386/x32-avx512.c: Regenerate.
The only reason .dat files exist is for GBBserver to use them in its
build system.
A few .dat files are listed as targets for generation that shouldn't.
The target descriptions these files are built from aren't used by
GDBserver. They're fallback descriptions GDB itself has baked in.
Remove them from the list of .dat files to be generated, otherwise a
plain "make" under src/gdb/features/ generates new .dat files that
aren't even in the tree today.
gdb/
2014-10-01 Pedro Alves <palves@redhat.com>
* features/Makefile (WHICH): Remove arm-with-m,
arm-with-m-fpa-layout and arm-with-m-vfp-d16.
So that we can do "make clean all" to regenerate all the renerated
.dat files.
gdb/
2014-10-01 Pedro Alves <palves@redhat.com>
* features/Makefile (clean): New rule.
This file's format is invalid, as it's missing some end quotes.
I noticed this because I tried to regenerate all the .dat files in
gdb/regformats/. I got:
sh ../../move-if-change ../regformats/i386/x32-avx.tmp ../regformats/i386/x32-avx.dat
echo "# DO NOT EDIT: generated from i386/x32-avx512.xml" > ../regformats/i386/x32-avx512.tmp
echo "name:`echo x32-avx512 | sed 's/-/_/g'`" >> ../regformats/i386/x32-avx512.tmp
echo "xmltarget:x32-avx512.xml" >> ../regformats/i386/x32-avx512.tmp
echo "expedite:rbp,rsp,rip" \
>> ../regformats/i386/x32-avx512.tmp
xsltproc --path "/home/pedro/gdb/mygit/src/gdb/features" --xinclude number-regs.xsl i386/x32-avx512.xml | \
xsltproc sort-regs.xsl - | \
xsltproc gdbserver-regs.xsl - >> ../regformats/i386/x32-avx512.tmp
i386/64bit-avx512.xml:81: parser error : Unescaped '<' not allowed in attributes values
<reg name="zmm11h" bitsize="256" type="v2ui128/>
^
i386/64bit-avx512.xml:81: parser error : attributes construct error
<reg name="zmm11h" bitsize="256" type="v2ui128/>
^
i386/64bit-avx512.xml:81: parser error : Couldn't find end of Start Tag reg line 80
<reg name="zmm11h" bitsize="256" type="v2ui128/>
^
i386/64bit-avx512.xml:82: parser error : Unescaped '<' not allowed in attributes values
<reg name="zmm12h" bitsize="256" type="v2ui128/>
^
i386/64bit-avx512.xml:82: parser error : attributes construct error
<reg name="zmm12h" bitsize="256" type="v2ui128/>
^
...
i386/x32-avx512.xml:17: element include: XInclude error : could not load i386/64bit-avx512.xml, and no fallback was found
-:1: parser error : Document is empty
^
-:1: parser error : Start tag expected, '<' not found
^
unable to parse -
-:1: parser error : Document is empty
^
-:1: parser error : Start tag expected, '<' not found
^
unable to parse -
make: *** [../regformats/i386/x32-avx512.dat] Error 6
Interestingly, gdb/expat manages to grok the broken file.
gdb/
2014-10-01 Pedro Alves <palves@redhat.com>
* features/i386/64bit-avx512.xml (zmm10h, zmm11h, zmm12h, zmm13h)
(zmm14h): Add missing end quotes.
