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2024-05-16Stop 'configure --enable-threading' if std::thread doesn't workPedro Alves1-3/+11
Currently, if you configure gdb with explicit --enable-threading, but then configure detects std::thread does not work, configure silently disables threading support and continues configuring. This patch makes that scenario cause a configuration error, like so: $ /home/pedro/gdb/src/configure --enable-threading && make ... configure: error: std::thread does not work; disable threading make[1]: *** [Makefile:11225: configure-gdbsupport] Error 1 make[1]: Leaving directory '/home/pedro/gdb/build-windows-threads' make: *** [Makefile:1041: all] Error 2 $ Additionally, if you don't explicitly pass --enable-threading, and std::thread does not work, we will now get a warning (and the build continues): $ /home/pedro/gdb/src/configure && make ... configure: WARNING: std::thread does not work; disabling threading ... This is similar to how we handle --enable-tui and missing curses. The code and error/warning messages were borrowed from there. Change-Id: I73a8b580d1e2a796b23136920c0e181408ae1b22 Approved-By: Tom Tromey <tom@tromey.com>
2024-05-07gdbserver: convert have_ptrace_getregset to a triboolAndrew Burgess4-10/+10
Convert the have_ptrace_getregset global within gdbserver to a tribool. This brings the flag into alignment with the corresponding flag in GDB. The gdbserver have_ptrace_getregset variable is already used as a tribool, it just doesn't have the tribool type. In a future commit I plan to share more code between GDB and gdbserver, and having this variable be the same type in both code bases will make the sharing much easier. There should be no user visible changes after this commit. Approved-By: John Baldwin <jhb@FreeBSD.org> Reviewed-By: Felix Willgerodt <felix.willgerodt@intel.com>
2024-05-07gdbserver/ipa/x86: remove unneeded declarationsAndrew Burgess1-4/+0
Spotted some declarations in gdbserver/linux-amd64-ipa.cc that are no longer needed. These are: 1. 'init_registers_amd64_linux' - the comment claims this function is auto generated, but I don't believe that this is still the case. Also the function is not used in this file, 2. 'tdesc_amd64_linux' - this variable doesn't seem to exist any more, I suspect this was renamed to 'tdesc_amd64_linux_no_xml', but neither are used in this file, so lets remove the declaration. The amd64 in-process-agent still builds fine after this commit. There should be no user visible changes after this commit. Approved-By: Felix Willgerodt <felix.willgerodt@intel.com>
2024-05-06Fix build issues with mingw toolchainBernd Edlinger1-0/+1
With a x86_64-pc-mingw32 toolchain there is a build issue whether or not the --disable-threading option is used. The problem happens because _WIN32_WINNT is defined to 0x501 before #include <mutex> which makes the compilation abort due to missing support for __gthread_cond_t in std_mutex.h, which is conditional on _WIN32_WINNT >= 0x600. Fix the case when --disable-threading is used, by only including <mutex> in gdb/complaints.c when STD_CXX_THREAD is defined. Additionally make the configure script try to #include <mutex> to automatically select --disable-threading when the header file is not able to compile. Approved-By: Tom Tromey <tom@tromey.com>
2024-05-03[gdb/build] Fix gdbserver/linux-aarch64-low.cc buildMark Wielaard1-1/+1
Commit 0ee25f97d21e ("Fix regression on aarch64-linux gdbserver") removed the last use of i in gdbserver/linux-aarch64-low.cc (aarch64_target::low_stopped_data_address). Breaking the build on aarch64 with: gdbserver/linux-aarch64-low.cc: In member function ?virtual CORE_ADDR aarch64_target::low_stopped_data_address()?: gdbserver/linux-aarch64-low.cc:557:12: error: unused variable ?i? [-Werror=unused-variable] 557 | int pid, i; | ^ cc1plus: all warnings being treated as errors Fix this by removing the variable i completely. Fixes: 0ee25f97d21e ("Fix regression on aarch64-linux gdbserver")
2024-05-02Fix regression on aarch64-linux gdbserverTom Tromey1-35/+3
Commit 9a03f218 ("Fix gdb.base/watchpoint-unaligned.exp on aarch64") fixed a watchpoint bug in gdb -- but did not touch the corresponding code in gdbserver. This patch moves the gdb code into gdb/nat, so that it can be shared with gdbserver, and then changes gdbserver to use it, fixing the bug. This is yet another case where having a single back end would prevent bugs. I tested this using the AdaCore internal gdb testsuite. Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=29423 Approved-By: Luis Machado <luis.machado@arm.com>
2024-04-26gdbserver: Fix vAttach response when attaching is not supportedPedro Alves1-1/+4
handle_v_attach calls attach_inferior, which says: "return -1 if attaching is unsupported, 0 if it succeeded, and call error() otherwise." So if attach_inferior return != 0, we have the unsupported case, meaning we should return the empty packet instead of an error. In practice, this shouldn't trigger, as vAttach support is supposed to be reported via qSupported. But it doesn't hurt to be pedantic here. Change-Id: I99cce6fa678f2370571e6bca0657451300956127 Approved-By: Tom Tromey <tom@tromey.com>
2024-04-26Fix "attach" failure handling with GDBserverPedro Alves1-17/+24
This fixes the same issue as the previous patch, but for "attach" instead of "run". If attaching to a process with "attach" (vAttach packet) fails, GDBserver throws an error that escapes all the way to the top level. When an error escapes all the way like that, GDBserver interprets it as a disconnection, and either goes back to waiting for a new GDB connection, or exits, if --once was specified. Here's an example: On the GDB side: ... (gdb) tar extended-remote :9999 ... Remote debugging using :9999 (gdb) attach 1 Attaching to process 1 Attaching to process 1 failed (gdb) On the GDBserver side: $ gdbserver --once --multi :9999 Listening on port 9999 Remote debugging from host 127.0.0.1, port 37464 gdbserver: Cannot attach to process 1: Operation not permitted (1) $ # gdbserver exited This is wrong, as we've connected with extended-remote/--multi. GDBserver should just report an error to vAttach, and continue connected to GDB, waiting for other commands. This commit fixes GDBserver by catching the error locally in handle_v_attach. Note we now let pid == 0 pass down to attach_inferior. That is so we get a useful textual error message to report to GDB. This fixes a couple KFAILs in gdb.base/attach.exp. Still, I thought it would be useful to add a new testcase specifically for this scenario, in case gdb.base/attach.exp is ever split and stops trying to attach again after a failed attach, with the same GDB session. Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=19558 Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=31554 Change-Id: I25314c7e5f1435eff69cb84d57ecac13d8de3393 Approved-By: Tom Tromey <tom@tromey.com>
2024-04-26Fix "run" failure handling with GDBserverPedro Alves1-1/+9
If starting the inferior process with "run" (vRun packet) fails, GDBserver throws an error that escapes all the way to the top level. When an error escapes all the way like that, GDBserver interprets it as a disconnection, and either goes back to waiting for a new GDB connection, or exits, if --once was specified. E.g., with the testcase program added by this commit, we see: On GDB side: ... (gdb) tar extended-remote :999 ... Remote debugging using :9999 (gdb) r Starting program: Running ".../gdb.base/run-fail-twice/run-fail-twice.nox" on the remote target failed (gdb) On GDBserver side: $ gdbserver --once --multi :9999 Remote debugging from host 127.0.0.1, port 34344 bash: line 1: .../gdb.base/run-fail-twice/run-fail-twice.nox: Permission denied bash: line 1: exec: .../gdb.base/run-fail-twice/run-fail-twice.nox: cannot execute: Permission denied gdbserver: During startup program exited with code 126. $ # gdbserver exited This is wrong, as we've connected with extended-remote/--multi. GDBserver should just report an error to vCont, and continue connected to GDB, waiting for other commands. This commit fixes GDBserver by catching the error locally in handle_v_run. Change-Id: Ib386f267522603f554b52a885b15229c9639e870 Approved-By: Tom Tromey <tom@tromey.com>
2024-04-18gdbsupport: constify some return values in print-utils.{h,cc}Simon Marchi2-2/+2
There is no reason the callers of these functions need to change the returned string, so change the `char *` return types to `const char *`. Update a few callers to also use `const char *`. Change-Id: I94adff574d5e1b326e8cc688cf1817a15b408b96 Approved-By: Tom Tromey <tom@tromey.com>
2024-04-17gdb+gdbserver/Linux: Remove USE_SIGTRAP_SIGINFO fallbackPedro Alves1-37/+2
It's been over 9 years (since commit faf09f0119da) since Linux GDB and GDBserver started relying on SIGTRAP si_code to tell whether a breakpoint triggered, which is important for non-stop mode. When that then-new code was added, I had left the then-old code as fallback, in case some architectured still needed it. Given AFAIK there haven't been complaints since, this commit finally removes the fallback code, along with USE_SIGTRAP_SIGINFO. Change-Id: I140a5333a9fe70e90dbd186aca1f081549b2e63d
2024-04-17gdbsupport, gdbserver, gdb: use -Wno-vla-cxx-extensionSimon Marchi1-0/+1
When building with clang 18, I see: CXX aarch64-linux-tdep.o /home/smarchi/src/binutils-gdb/gdb/aarch64-linux-tdep.c:1299:26: error: variable length arrays in C++ are a Clang extension [-Werror,-Wvla-cxx-extension] 1299 | gdb_byte za_zeroed[za_bytes]; | ^~~~~~~~ /home/smarchi/src/binutils-gdb/gdb/aarch64-linux-tdep.c:1299:26: note: read of non-const variable 'za_bytes' is not allowed in a constant expression /home/smarchi/src/binutils-gdb/gdb/aarch64-linux-tdep.c:1282:10: note: declared here 1282 | size_t za_bytes = std::pow (sve_vl_from_vg (svg), 2); | ^ Since we are using VLAs right now, that warning doesn't make sense for us. add `-Wno-vla-cxx-extension` to the list of warning flags we try to enable. If we ever choose to disallow VLAs, we can remove that flag. Change-Id: Ie41feafc50c343f6e75333d4f836ce32fbeb6d8c
2024-04-10gdb, gdbserver: Add missing install-dvi Makefile targetChristophe Lyon1-0/+1
For some reason install-dvi is missing although other targets of the same family are present. This looks like an oversight. This enables calling 'make install-dvi' from the top-level build directory. Fix what looks like another oversight: include 'pdf' in 'all-doc' in gdb/doc/Makefile.in. Approved-By: Luis Machado <luis.machado@arm.com> Tested-By: Luis Machado <luis.machado@arm.com>
2024-03-26gdb, gdbserver, gdbsupport: remove includes of early headersSimon Marchi56-57/+0
Now that defs.h, server.h and common-defs.h are included via the `-include` option, it is no longer necessary for source files to include them. Remove all the inclusions of these files I could find. Update the generation scripts where relevant. Change-Id: Ia026cff269c1b7ae7386dd3619bc9bb6a5332837 Approved-By: Pedro Alves <pedro@palves.net>
2024-03-26gdb, gdbserver, gdbsupport: include early header files with `-include`Simon Marchi1-2/+12
The motivation for this change is for analysis tools and IDEs to be better at analyzing header files on their own. There are some definitions and includes we want to occur at the very beginning of all translation units. The way we currently do that is by requiring all source files (.c and .cc files) to include one of defs.h (for gdb), server.h (for gdbserver) of common-defs.h (for gdbsupport and shared source files). These special header files define and include everything that needs to be included at the very beginning. Other header files are written in a way that assume that these special "prologue" header files have already been included. My problem with that is that my editor (clangd-based) provides a very bad experience when editing header files. Since clangd doesn't know that one of defs.h/server.h/common-defs.h was included already, a lot of things are flagged as errors. For instance, CORE_ADDR is not known. It's possible to edit the files in this state, but a lot of the power of the editor is unavailable. My proposal to help with this is to include those things we always want to be there using the compilers' `-include` option. Tom Tromey said that the current approach might exist because not all compilers used to have an option like this. But I believe that it's safe to assume they do today. With this change, clangd picks up the -include option from the compile command, and is able to analyze the header file correctly, as it sees all that stuff included or defined by that -include option. That works because when editing a header file, clangd tries to get the compilation flags from a source file that includes said header file. This change is a bit self-serving, because it addresses one of my frustrations when editing header files, but it might help others too. I'd be curious to know if others encounter the same kinds of problems when editing header files. Also, even if the change is not necessary by any means, I think the solution of using -include for stuff we always want to be there is more elegant than the current solution. Even with this -include flag, many header files currently don't include what they use, but rather depend on files included before them. This will still cause errors when editing them, but it should be easily fixable by adding the appropriate include. There's no rush to do so, as long as the code still compiles, it's just a convenience thing. The changes are: - Add the appropriate `-include` option to the various Makefiles. - There is one particularity for gdbserver's Makefile: we do not want to include server.h when building `gdbreplay.o`, as `gdbreplay.cc` doesn't include it. So we can't simply put the `-include` in `INTERNAL_CFLAGS`. Add the `-include server.h` option to the `COMPILE` and `IPAGENT_COMPILE` variables, and added a special rule to compile `gdbreplay.o` with `-include gdbsupport/common-defs.h`. - Remove the `-include` option from the `check-headers` rule in gdb/Makefile.in, since it is already included in `INTERNAL_CFLAGS`. Change-Id: If3e345d00a9fc42336322f1d8286687d22134340 Approved-By: Pedro Alves <pedro@palves.net>
2024-03-26{gdb,gdbserver}/Makefile.in: remove unnecessary intermediary variablesSimon Marchi1-9/+3
Remove `INTERNAL_CFLAGS_BASE` and `INTERNAL_WARN_CFLAGS`, inline their contents in `INTERNAL_CFLAGS`. Not functional changes expected. Change-Id: I6a09794835ca2cfd4a88a3e9f2e627c8f5bd569f Approved-By: Pedro Alves <pedro@palves.net>
2024-03-26gdb, gdbserver, gdbsupport: reformat some Makefile variables, one entry per lineSimon Marchi1-12/+38
Reformat some variables definitions. I think it makes them easier to read, and it also makes diffs clearer. Change-Id: I82f63ba0e6d0fe268eb1f1ad5ab22c3cd016ab02 Approved-By: Pedro Alves <pedro@palves.net>
2024-03-26Revert "gdbserver: convert have_ptrace_getregset to a tribool"Andrew Burgess4-10/+10
This reverts commit 5920765d7513aaae9241a1850d62d73e0477f81c.
2024-03-26Revert "gdbserver/x86: move no-xml code earlier in x86_linux_read_description"Andrew Burgess1-16/+11
This reverts commit 0a7bb97ad2f2fe2d18a442dad265051e34eab13e.
2024-03-26Revert "gdb/gdbserver: share I386_LINUX_XSAVE_XCR0_OFFSET definition"Andrew Burgess1-1/+21
This reverts commit 7816b81e9b36ea0f57662bfd7446b573bf0c9e54.
2024-03-26Revert "gdb/gdbserver: share some code relating to target description creation"Andrew Burgess6-49/+111
This reverts commit cd9b374ffe372dcaf7e4c15548cf53a301d8dcdd.
2024-03-26Revert "gdbserver: update target description creation for x86/linux"Andrew Burgess5-277/+168
This reverts commit 61bb321605fc74703adc994fd7a78e9d2495ca7a.
2024-03-26Revert "gdb/gdbserver: share x86/linux tdesc caching"Andrew Burgess7-12/+332
This reverts commit 198ff6ff819c240545f9fc68b39636fd376d4ba9.
2024-03-26Revert "gdbserver/Makefile.in: add missing `-x c++`"Andrew Burgess1-1/+1
This reverts commit c7c9820071f8b81a64221f5cfafb3cbfeafe7916.
2024-03-25gdbserver/Makefile.in: add missing `-x c++`Simon Marchi1-1/+1
When building with Clang, I get: CXX nat/x86-linux-tdesc-ipa.o clang++: error: treating 'c' input as 'c++' when in C++ mode, this behavior is deprecated [-Werror,-Wdeprecated] Fix that by adding the missing `-x c++` in the rule building `gdb/nat/*.c` files for the in-process agent. Change-Id: Ie53e4b9a8b57bef9669397fdfaf21617107c7180 Approved-By: Tom Tromey <tom@tromey.com>
2024-03-25gdb/gdbserver: share x86/linux tdesc cachingAndrew Burgess7-332/+12
This commit builds on the previous series of commits to share the target description caching code between GDB and gdbserver for x86/Linux targets. The objective of this commit is to move the four functions (2 each of) i386_linux_read_description and amd64_linux_read_description into gdb/nat/x86-linux-tdesc.c and combine them so we have just a single copy of each. Then both GDB and gdbserver will link against these shared functions. It is worth reading the description of the previous commit to see why this merging is not as simple as it seems: on the gdbserver side we actually have two users of these functions, gdbserver itself, and the in process agent (IPA). However, the previous commit streamlined the gdbserver code, and so now it is simple to move the two functions along with all their support functions from the gdbserver directory into the gdb/nat/ directory, and then GDB is fine to call these functions. One small curiosity with this patch is the function x86_linux_post_init_tdesc. On the gdbserver side the two functions amd64_linux_read_description and i386_linux_read_description have some functionality that is not present on the GDB side, that is some additional configuration that is performed as each target description is created to setup the expedited registers. To support this I've added the function x86_linux_post_init_tdesc. This function is called from the two *_linux_read_description functions, but is implemented separately for GDB and gdbserver. This does mean adding back some non-shared code when this whole series has been about sharing code, but now the only non-shared bit is the single line that is actually different between GDB and gdbserver, all the rest, which is identical, is now shared. I did need to add a new rule to the gdbserver Makefile, this is to allow the nat/x86-linux-tdesc.c file to be compiled for the IPA. Approved-By: John Baldwin <jhb@FreeBSD.org>
2024-03-25gdbserver: update target description creation for x86/linuxAndrew Burgess5-168/+277
This commit is part of a series which aims to share more of the target description creation between GDB and gdbserver for x86/Linux. After some refactoring, the previous commit actually started to share some code, we added the shared x86_linux_tdesc_for_tid function into nat/x86-linux-tdesc.c. However, this function still relies on amd64_linux_read_description and i386_linux_read_description which are implemented separately for both gdbserver and GDB. Given that at their core, all these functions to is: 1. take an xcr0 value as input, 2. mask out some feature bits, 3. look for a cached pre-generated target description and return it if found, 4. if no cached target description is found then call either amd64_create_target_description or i386_create_target_description to create a new target description, which is then added to the cache. Return the newly created target description. The inner functions amd64_create_target_description and i386_create_target_description are already shared between GDB and gdbserver (in the gdb/arch/ directory), so the only thing that the *_read_description functions really do is add the caching layer, and it feels like this really could be shared. However, we have a small problem. On the GDB side we create target descriptions using a different set of cpu features than on the gdbserver side! This means that for the exact same target, we might get a different target description when using native GDB vs using gdbserver. This surely feels like a mistake, I would expect to get the same target description on each. The table below shows the number of possible different target descriptions that we can create on the GDB side vs on the gdbserver side for each target type: | GDB | gdbserver ------|-----|---------- i386 | 64 | 7 amd64 | 32 | 7 x32 | 16 | 7 So in theory, all I want to do is move the GDB version of *_read_description into the nat/ directory and have gdbserver use that, then both GDB and gdbserver would be able to create any of the possible target descriptions. Unfortunately it's a little more complex than that due to the in process agent (IPA). When the IPA is in use, gdbserver sends a target description index to the IPA, and the IPA uses this to find the correct target description to use. ** START OF AN ASIDE ** Back in the day I suspect this approach made perfect sense. However since this commit: commit a8806230241d201f808d856eaae4d44088117b0c Date: Thu Dec 7 17:07:01 2017 +0000 Initialize target description early in IPA I think passing the index is now more trouble than its worth. We used to pass the index, and then use that index to lookup which target description to instantiate and use. However, the above commit fixed an issue where we can't call malloc() within (certain parts of) the IPA (apparently), so instead we now pre-compute _every_ possible target description within the IPA. The index is now only used to lookup which of the (many) pre-computed target descriptions to use. It would (I think) have been easier all around if the IPA just self-inspected, figured out its own xcr0 value, and used that to create the one target description that is required. So long as the xcr0 to target description code is shared (at compile time) with gdbserver, then we can be sure that the IPA will derive the same target description as gdbserver, and we would avoid all this index passing business, which has made this commit so very, very painful. ** END OF AN ASIDE ** Currently then for x86/linux, gdbserver sends a number between 0 and 7 to the IPA, and the IPA uses this to create a target description. However, I am proposing that gdbserver should now create one of (up to) 64 different target descriptions for i386, so this 0 to 7 index isn't going to be good enough any more (amd64 and x32 have slightly fewer possible target descriptions, but still more than 8, so the problem is the same). For a while I wondered if I was going to have to try and find some backward compatible solution for this mess. But after seeing how lightly the IPA is actually documented, I wonder if it is not the case that there is a tight coupling between a version of gdbserver and a version of the IPA? At least I'm hoping so. In this commit I have thrown out the old IPA target description index numbering scheme, and switched to a completely new numbering scheme. Instead of the index that is passed being arbitrary, the index is instead calculated from the set of cpu features that are present on the target. Within the IPA we can then reverse this logic to recreate the xcr0 value based on the index, and from the xcr0 value we can create the correct target description. With the gdbserver to IPA numbering scheme issue resolved I have then update the gdbserver versions of amd64_linux_read_description and i386_linux_read_description so that they create target descriptions using the same set of cpu features as GDB itself. After this gdbserver should now always come up with the same target description as GDB does on any x86/Linux target. This commit does not introduce any new code sharing between GDB and gdbserver as previous commits in this series does. Instead this commit is all about bringing GDB and gdbserver into alignment functionally so that the next commit can merge the GDB and gdbserver versions of these functions. Approved-By: John Baldwin <jhb@FreeBSD.org>
2024-03-25gdb/gdbserver: share some code relating to target description creationAndrew Burgess6-111/+49
This commit is part of a series to share more of the x86 target description creation code between GDB and gdbserver. Unlike previous commits which were mostly refactoring, this commit is the first that makes a real change, though that change should mostly be for gdbserver; I've largely adopted the "GDB" way of doing things for gdbserver, and this fixes a real gdbserver bug. On a x86-64 Linux target, running the test: gdb.server/connect-with-no-symbol-file.exp results in two core files being created. Both of these core files are from the inferior process, created after gdbserver has detached. In this test a gdbserver process is started and then, after gdbserver has started, but before GDB attaches, we either delete the inferior executable, or change its permissions so it can't be read. Only after doing this do we attempt to connect with GDB. As GDB connects to gdbserver, gdbserver attempts to figure out the target description so that it can send the description to GDB, this involves a call to x86_linux_read_description. In x86_linux_read_description one of the first things we do is try to figure out if the process is 32-bit or 64-bit. To do this we look up the executable via the thread-id, and then attempt to read the architecture size from the executable. This isn't going to work if the executable has been deleted, or is no longer readable. And so, as we can't read the executable, we default to an i386 target and use an i386 target description. A consequence of using an i386 target description is that addresses are assumed to be 32-bits. Here's an example session that shows the problems this causes. This is run on an x86-64 machine, and the test binary (xx.x) is a standard 64-bit x86-64 binary: shell_1$ gdbserver --once localhost :54321 /tmp/xx.x shell_2$ gdb -q (gdb) set sysroot (gdb) shell chmod 000 /tmp/xx.x (gdb) target remote :54321 Remote debugging using :54321 warning: /tmp/xx.x: Permission denied. 0xf7fd3110 in ?? () (gdb) show architecture The target architecture is set to "auto" (currently "i386"). (gdb) p/x $pc $1 = 0xf7fd3110 (gdb) info proc mappings process 2412639 Mapped address spaces: Start Addr End Addr Size Offset Perms objfile 0x400000 0x401000 0x1000 0x0 r--p /tmp/xx.x 0x401000 0x402000 0x1000 0x1000 r-xp /tmp/xx.x 0x402000 0x403000 0x1000 0x2000 r--p /tmp/xx.x 0x403000 0x405000 0x2000 0x2000 rw-p /tmp/xx.x 0xf7fcb000 0xf7fcf000 0x4000 0x0 r--p [vvar] 0xf7fcf000 0xf7fd1000 0x2000 0x0 r-xp [vdso] 0xf7fd1000 0xf7fd3000 0x2000 0x0 r--p /usr/lib64/ld-2.30.so 0xf7fd3000 0xf7ff3000 0x20000 0x2000 r-xp /usr/lib64/ld-2.30.so 0xf7ff3000 0xf7ffb000 0x8000 0x22000 r--p /usr/lib64/ld-2.30.so 0xf7ffc000 0xf7ffe000 0x2000 0x2a000 rw-p /usr/lib64/ld-2.30.so 0xf7ffe000 0xf7fff000 0x1000 0x0 rw-p 0xfffda000 0xfffff000 0x25000 0x0 rw-p [stack] 0xff600000 0xff601000 0x1000 0x0 r-xp [vsyscall] (gdb) info inferiors Num Description Connection Executable * 1 process 2412639 1 (remote :54321) (gdb) shell cat /proc/2412639/maps 00400000-00401000 r--p 00000000 fd:03 45907133 /tmp/xx.x 00401000-00402000 r-xp 00001000 fd:03 45907133 /tmp/xx.x 00402000-00403000 r--p 00002000 fd:03 45907133 /tmp/xx.x 00403000-00405000 rw-p 00002000 fd:03 45907133 /tmp/xx.x 7ffff7fcb000-7ffff7fcf000 r--p 00000000 00:00 0 [vvar] 7ffff7fcf000-7ffff7fd1000 r-xp 00000000 00:00 0 [vdso] 7ffff7fd1000-7ffff7fd3000 r--p 00000000 fd:00 143904 /usr/lib64/ld-2.30.so 7ffff7fd3000-7ffff7ff3000 r-xp 00002000 fd:00 143904 /usr/lib64/ld-2.30.so 7ffff7ff3000-7ffff7ffb000 r--p 00022000 fd:00 143904 /usr/lib64/ld-2.30.so 7ffff7ffc000-7ffff7ffe000 rw-p 0002a000 fd:00 143904 /usr/lib64/ld-2.30.so 7ffff7ffe000-7ffff7fff000 rw-p 00000000 00:00 0 7ffffffda000-7ffffffff000 rw-p 00000000 00:00 0 [stack] ffffffffff600000-ffffffffff601000 r-xp 00000000 00:00 0 [vsyscall] (gdb) Notice the difference between the mappings reported via GDB and those reported directly from the kernel via /proc/PID/maps, the addresses of every mapping is clamped to 32-bits for GDB, while the kernel reports real 64-bit addresses. Notice also that the $pc value is a 32-bit value. It appears to be within one of the mappings reported by GDB, but is outside any of the mappings reported from the kernel. And this is where the problem arises. When gdbserver detaches from the inferior we pass the inferior the address from which it should resume. Due to the 32/64 bit confusion we tell the inferior to resume from the 32-bit $pc value, which is not within any valid mapping, and so, as soon as the inferior resumes, it segfaults. If we look at how GDB (not gdbserver) figures out its target description then we see an interesting difference. GDB doesn't try to read the executable. Instead GDB uses ptrace to query the thread's state, and uses this to figure out the if the thread is 32 or 64 bit. If we update gdbserver to do it the "GDB" way then the above problem is resolved, gdbserver now sees the process as 64-bit, and when we detach from the inferior we give it the correct 64-bit address, and the inferior no longer segfaults. Now, I could just update the gdbserver code, but better, I think, to share one copy of the code between GDB and gdbserver in gdb/nat/. That is what this commit does. The cores of x86_linux_read_description from gdbserver and x86_linux_nat_target::read_description from GDB are moved into a new file gdb/nat/x86-linux-tdesc.c and combined into a single function x86_linux_tdesc_for_tid which is called from each location. This new function does things the GDB way, the only changes are to allow for the sharing; we now have a callback function to call the first time that the xcr0 state is read, this allows for GDB and gdbserver to perform their own initialisation as needed, and additionally, the new function takes a pointer for where to cache the xcr0 value, this isn't needed for this commit, but will be useful in a later commit where gdbserver will want to read this cached xcr0 value. Another thing to note about this commit is how the functions i386_linux_read_description and amd64_linux_read_description are handled. For now I've left these function as implemented separately in GDB and gdbserver. I've moved the declarations of these functions into gdb/nat/x86-linux-tdesc.h, but the implementations are left as separate. A later commit in this series will make these functions shared too, but doing this is not trivial, so I've left that for a separate commit. Merging the declarations as I've done here ensures that everyone implements the function to the same API, and once these functions are shared (in a later commit) we'll want a shared declaration anyway. Approved-By: John Baldwin <jhb@FreeBSD.org>
2024-03-25gdb/gdbserver: share I386_LINUX_XSAVE_XCR0_OFFSET definitionAndrew Burgess1-21/+1
Share the definition of I386_LINUX_XSAVE_XCR0_OFFSET between GDB and gdbserver. This commit is part of a series that aims to share more of the x86 target description creation code between GDB and gdbserver. The I386_LINUX_XSAVE_XCR0_OFFSET #define is used as part of the target description creation, and I noticed that this constant is defined separately for GDB and gdbserver. This commit moves the definition into gdb/nat/x86-linux.h, which allows the #define to be shared. There should be no user visible changes after this commit. Approved-By: John Baldwin <jhb@FreeBSD.org>
2024-03-25gdbserver/x86: move no-xml code earlier in x86_linux_read_descriptionAndrew Burgess1-11/+16
This commit is part of a series that aims to share more of the x86 target description reading/generation code between GDB and gdbserver. There are a huge number of similarities between the code in gdbserver's x86_linux_read_description function and GDB's x86_linux_nat_target::read_description function, and it is this similarity that I plan, in a later commit, to share between GDB and gdbserver. However, one thing that is different in x86_linux_read_description is the code inside the '!use_xml' block. This is the code that handles the case where gdbserver is not allowed to send an XML target description back to GDB. In this case gdbserver uses some predefined, fixed, target descriptions. First, it's worth noting that I suspect this code is not tested any more. I couldn't find anything in the testsuite that tries to disable XML target description support. And the idea of having a single "fixed" target description really doesn't work well when we think about all the various x86 extensions that exist. Part of me would like to rip out the no-xml support in gdbserver (at least for x86), and if a GDB connects that doesn't support XML target descriptions, gdbserver can just give an error and drop the connection. GDB has supported XML target descriptions for 16 years now, I think it would be reasonable for our shipped gdbserver to drop support for the old way of doing things. Anyway.... this commit doesn't do that. What I did notice was that, over time, the '!use_xml' block appears to have "drifted" within the x86_linux_read_description function; it's now not the first check we do. Instead we make some ptrace calls and return a target description generated based on the result of these ptrace calls. Surely it only makes sense to generate variable target descriptions if we can send these back to GDB? So in this commit I propose to move the '!use_xml' block earlier in the x86_linux_read_description function. The benefit of this is that this leaves the later half of x86_linux_read_description much more similar to the GDB function x86_linux_nat_target::read_description and sets us up for potentially sharing code between GDB and gdbserver in a later commit. Approved-By: John Baldwin <jhb@FreeBSD.org>
2024-03-25gdbserver: convert have_ptrace_getregset to a triboolAndrew Burgess4-10/+10
Convert the have_ptrace_getregset global within gdbserver to a tribool. This brings the flag into alignment with the corresponding flag in GDB. The gdbserver have_ptrace_getregset variable is already used as a tribool, it just doesn't have the tribool type. In a future commit I plan to share more code between GDB and gdbserver, and having this variable be the same type in both code bases will make the sharing much easier. There should be no user visible changes after this commit. Approved-By: John Baldwin <jhb@FreeBSD.org>
2024-03-21gdbserver: Clear X86_XSTATE_MPX bits in xcr0 on x32H.J. Lu1-0/+4
Since MPX isn't available for x32, we should clear X86_XSTATE_MPX bits on x32. PR server/31511 * linux-x86-low.cc (x86_linux_read_description): Clear X86_XSTATE_MPX bits in xcr0 on x32. Reviewed-by: Felix Willgerodt <felix.willgerodt@intel.com>
2024-03-14gdbserver/linux: probe for libiconv in configureSimon Marchi6-5/+381
Make gdbserver's build system locate libiconv when building for Linux. Commit 07b3255c3bae ("Filter invalid encodings from Linux thread names") make libiconv madantory for building gdbserver on Linux. While trying to cross-compile gdb for xtensa-fsf-linux-uclibc (with a toolchain generated with crosstool-ng), I got: /home/smarchi/src/binutils-gdb/gdbserver/linux-low.cc:48:10: fatal error: iconv.h: No such file or directory 48 | #include <iconv.h> | ^~~~~~~~~ I downloaded GNU libiconv, built it for that host, and installed it in an arbitrary directory. I had to modify the gdbserver build system to locate libiconv and use it, the result is this patch. I eventually found that crosstool-ng has a config option to make uclibc provide an implementation of iconv, which is of course much easier. But given that this patch is now written, I think it would be worth merging it, it could help some people who do not have iconv built-in their libc in the future (and may not have the luxury of rebuilding their libc like I do). Using AM_ICONV in configure.ac adds these options for configure (the same we have for gdb): --with-libiconv-prefix[=DIR] search for libiconv in DIR/include and DIR/lib --without-libiconv-prefix don't search for libiconv in includedir and libdir --with-libiconv-type=TYPE type of library to search for (auto/static/shared) It sets the `LIBICONV` variable with whatever is needed to link with libiconv, and adds the necessary `-I` flag to `CPPFLAGS`. To avoid unnecessarily linking against libiconv on hosts that don't need it, set `MAYBE_LIBICONV` with the contents of `LIBICONV` only if the host is Linux, and use `MAYBE_LIBICONV` in `Makefile.in`. Since libiconv is a hard requirement for Linux hosts, error out if it is not found. The bits in acinclude.m4 are similar to what we have in gdb/acinclude.m4. Update the top-level build system to support building against an in-tree libiconv (I did not test this part though). Something tells me that the all-gdbserver dependency on all-libiconv is unnecessary, since there is already a dependency of configure-gdbserver on all-libiconv (and all-gdbserver surely depends on configure-gdbserver). I just copied what's done for GDB though. ChangeLog: * Makefile.def: Add configure-gdbserver and all-gdbserver dependencies on all-libiconv. * Makefile.in: Re-generate. Change-Id: I90f8ef88dd4917df5a68b45550d93622fc9cfed4 Approved-By: Tom Tromey <tom@tromey.com>
2024-02-29gdb/arm: Remove tpidruro register from non-FreeBSD target descriptionsThiago Jung Bauermann1-1/+1
Commit 92d48a1e4eac ("Add an arm-tls feature which includes the tpidruro register from CP15.") introduced the org.gnu.gdb.arm.tls feature, which adds the tpidruro register, and unconditionally enabled it in aarch32_create_target_description. In Linux, the tpidruro register isn't available via ptrace in the 32-bit kernel but it is available for an aarch32 program running under an arm64 kernel via the ptrace compat interface. This isn't currently implemented however, which causes GDB on arm-linux with 64-bit kernel to list the register but show it as unavailable, as reported by Tom de Vries: $ gdb -q -batch a.out -ex start -ex 'p $tpidruro' Temporary breakpoint 1 at 0x512 Temporary breakpoint 1, 0xaaaaa512 in main () $1 = <unavailable> Simon Marchi then clarified: > The only time we should be seeing some "unavailable" registers or memory > is in the context of tracepoints, for things that are not collected. > Seeing an unavailable register here is a sign that something is not > right. Therefore, disable the TLS feature in aarch32 target descriptions for Linux and NetBSD targets (the latter also doesn't seem to support accessing tpidruro either, based on a quick look at arm-netbsd-nat.c). This patch fixes the following tests: Running gdb.base/inline-frame-cycle-unwind.exp ... FAIL: gdb.base/inline-frame-cycle-unwind.exp: cycle at level 3: backtrace when the unwind is broken at frame 3 FAIL: gdb.base/inline-frame-cycle-unwind.exp: cycle at level 5: backtrace when the unwind is broken at frame 5 FAIL: gdb.base/inline-frame-cycle-unwind.exp: cycle at level 1: backtrace when the unwind is broken at frame 1 Tested with Ubuntu 22.04.3 on armv8l-linux-gnueabihf in native, native-gdbserver and native-extended-gdbserver targets with no regressions. PR tdep/31418 Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=31418 Approved-By: John Baldwin <jhb@FreeBSD.org>
2024-02-26gdb: Modify the output of "info breakpoints" and "delete breakpoints"Tiezhu Yang2-6/+8
The output of "info breakpoints" includes breakpoint, watchpoint, tracepoint, and catchpoint if they are created, so it should show all the four types are deleted in the output of "info breakpoints" to report empty list after "delete breakpoints". It should also change the output of "delete breakpoints" to make it clear that watchpoints, tracepoints, and catchpoints are also being deleted. This is suggested by Guinevere Larsen, thank you. $ make check-gdb TESTS="gdb.base/access-mem-running.exp" $ gdb/gdb gdb/testsuite/outputs/gdb.base/access-mem-running/access-mem-running [...] (gdb) break main Breakpoint 1 at 0x12000073c: file /home/loongson/gdb.git/gdb/testsuite/gdb.base/access-mem-running.c, line 32. (gdb) watch global_counter Hardware watchpoint 2: global_counter (gdb) trace maybe_stop_here Tracepoint 3 at 0x12000071c: file /home/loongson/gdb.git/gdb/testsuite/gdb.base/access-mem-running.c, line 27. (gdb) catch fork Catchpoint 4 (fork) (gdb) info breakpoints Num Type Disp Enb Address What 1 breakpoint keep y 0x000000012000073c in main at /home/loongson/gdb.git/gdb/testsuite/gdb.base/access-mem-running.c:32 2 hw watchpoint keep y global_counter 3 tracepoint keep y 0x000000012000071c in maybe_stop_here at /home/loongson/gdb.git/gdb/testsuite/gdb.base/access-mem-running.c:27 not installed on target 4 catchpoint keep y fork Without this patch: (gdb) delete breakpoints Delete all breakpoints? (y or n) y (gdb) info breakpoints No breakpoints or watchpoints. (gdb) info breakpoints 3 No breakpoint or watchpoint matching '3'. With this patch: (gdb) delete breakpoints Delete all breakpoints, watchpoints, tracepoints, and catchpoints? (y or n) y (gdb) info breakpoints No breakpoints, watchpoints, tracepoints, or catchpoints. (gdb) info breakpoints 3 No breakpoint, watchpoint, tracepoint, or catchpoint matching '3'. Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn> Approved-by: Kevin Buettner <kevinb@redhat.com> Reviewed-By: Eli Zaretskii <eliz@gnu.org>
2024-02-21gdb: remove some GCC version checksSimon Marchi1-5/+1
Since we now require C++17, and therefore gcc >= 9, it's no longer useful to have gcc version checks for older gcc version. Change-Id: I3a87baa03c475f2b847b422b16b69c5ff7215b54 Reviewed-by: Kevin Buettner <kevinb@redhat.com> Approved-By: Pedro Alves <pedro@palves.net>
2024-02-09Fix crash in aarch64-linux gdbserverPedro Alves1-6/+15
Since commit 393a6b5947d0 ("Thread options & clone events (Linux GDBserver)"), aarch64-linux gdbserver crashes when the inferior vforks. This happens in aarch64_get_debug_reg_state: struct process_info *proc = find_process_pid (pid); return &proc->priv->arch_private->debug_reg_state; Here, find_process_pid returns nullptr -- the new inferior hasn't yet been created in linux_process_target::handle_extended_wait. This patch fixes the problem by having linux_process_target::handle_extended_wait create the child process earlier, before the child LWP is created. This is what the function did before it was reorganized by the commit referred above. Change-Id: Ib8b3a2e6048c3ad2b91a92ea4430da507db03c50 Co-Authored-By: Tom Tromey <tromey@adacore.com>
2024-02-06gdb: LoongArch: Add LBT extension supportFeiyang Chen1-0/+43
Loongson Binary Translation (LBT) is used to accelerate binary translation, which contains 4 scratch registers (scr0 to scr3), x86/ARM eflags (eflags) and x87 fpu stack pointer (ftop). This patch support gdb to fetch/store these registers. Signed-off-by: Feiyang Chen <chenfeiyang@loongson.cn> # Framework Signed-off-by: Binbin Zhou <zhoubinbin@loongson.cn> # Detail Optimizes Signed-off-by: Hui Li <lihui@loongson.cn> # Error Fixes Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
2024-02-06gdb: LoongArch: Add vector extensions supportHui Li1-0/+52
Add LoongArch's vector extensions support, which including 128bit LSX (i.e., Loongson SIMD eXtension) and 256bit LASX (i.e., Loongson Advanced SIMD eXtension). This patch support gdb to fetch/store vector registers. Signed-off-by: Hui Li <lihui@loongson.cn> Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
2024-01-30Really fix Windows gdbserver segment registersTom Tromey1-9/+76
My earlier attempt to mask the segment registers in gdbserver for Windows introduced some bugs. That patch is here: https://sourceware.org/pipermail/gdb-patches/2023-December/205306.html The problem turned out to be that these fields in the Windows 'CONTEXT' type are just 16 bits, so while masking the values on read is fine, writing the truncated values back then causes zeros to be written to some subsequent field. This patch cleans this up by arranging never to write too much data to a field. I also noticed that two register numbers here were never updated for the 64-bit port. This patch fixes this as well, and renames the "FCS" register to follow gdb. Finally, this patch applies the same treatment to windows-nat.c. Reviewed-by: John Baldwin <jhb@FreeBSD.org>
2024-01-12Update copyright year range in header of all files managed by GDBAndrew Burgess91-93/+93
This commit is the result of the following actions: - Running gdb/copyright.py to update all of the copyright headers to include 2024, - Manually updating a few files the copyright.py script told me to update, these files had copyright headers embedded within the file, - Regenerating gdbsupport/Makefile.in to refresh it's copyright date, - Using grep to find other files that still mentioned 2023. If these files were updated last year from 2022 to 2023 then I've updated them this year to 2024. I'm sure I've probably missed some dates. Feel free to fix them up as you spot them.
2024-01-10gdbsupport: tighten up libiberty code a bit with dnlMike Frysinger1-3/+1
No functional change here, just touch up generated output slightly. Approved-By: Tom Tromey <tom@tromey.com>
2024-01-10gdb: libiberty: switch to AC_CHECK_DECLS_ONCEMike Frysinger1-58/+69
Only check these decls once in case other m4 macros also look for them. Approved-By: Tom Tromey <tom@tromey.com>
2024-01-10gdb: move libiberty.m4 to gdbsupportMike Frysinger1-1/+1
This is used by gdb, gdbsupport, and gdbserver. We want to use it in the sim tree too. Move it to gdbsupport which is meant as the common sharing space for these projects. Approved-By: Tom Tromey <tom@tromey.com>
2024-01-09Fix two bugs in gdbserver thread name handlingTom Tromey1-3/+6
Simon pointed out that my earlier patch to gdbserver's thread name code: commit 07b3255c3bae7126a0d679f957788560351eb236 Author: Tom Tromey <tom@tromey.com> Date: Thu Jul 13 17:28:48 2023 -0600 Filter invalid encodings from Linux thread names ... introduced a regression. This bug was that the iconv output was not \0-terminated. Looking at it, I found another bug as well -- replace_non_ascii would not \0-terminate, and also would return the wrong pointer This patch fixes both of them. Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=31153
2023-12-14gdb: change regcache interface to use array_viewSimon Marchi2-23/+30
Change most of regcache (and base classes) to use array_view when possible, instead of raw pointers. By propagating the use of array_view further, it enables having some runtime checks to make sure the what we read from or write to regcaches has the expected length (such as the one in the `copy(array_view, array_view)` function. It also integrates well when connecting with other APIs already using gdb::array_view. Add some overloads of the methods using raw pointers to avoid having to change all call sites at once (which is both a lot of work and risky). I tried to do this change in small increments, but since many of these functions use each other, it ended up simpler to do it in one shot than having a lot of intermediary / transient changes. This change extends into gdbserver as well, because there is some part of the regcache interface that is shared. Changing the reg_buffer_common interface to use array_view caused some build failures in nat/aarch64-scalable-linux-ptrace.c. That file currently "takes advantage" of the fact that reg_buffer_common::{raw_supply,raw_collect} operates on `void *`, which IMO is dangerous. It uses raw_supply/raw_collect directly on uint64_t's, which I guess is fine because it is expected that native code will have the same endianness as the debugged process. To accomodate that, add some overloads of raw_collect and raw_supply that work on uint64_t. This file also uses raw_collect and raw_supply on `char` pointers. Change it to use `gdb_byte` pointers instead. Add overloads of raw_collect and raw_supply that work on `gdb_byte *` and make an array_view on the fly using the register's size. Those call sites could be converted to use array_view with not much work, in which case these overloads could be removed, but I didn't want to do it in this patch, to avoid starting to dig in arch-specific code. During development, I inadvertently changed reg_buffer::raw_compare's behavior to not accept an offset equal to the register size. This behavior (effectively comparing 0 bytes, returning true) change was caught by the AArch64 SME core tests. Add a selftest to make sure that this raw_compare behavior is preserved in the future. Change-Id: I9005f04114543ddff738949e12d85a31855304c2 Reviewed-By: John Baldwin <jhb@FreeBSD.org>
2023-12-14gdb: use reg_buffer_common throughout gdbsupport/common-regcache.hSimon Marchi2-7/+14
Right now, gdbsupport/common-regcache.h contains two abstractons for a regcache. An opaque type `regcache` (gdb and gdbserver both have their own regcache that is the concrete version of this) and an abstract base class `reg_buffer_common`, that is the base of regcaches on both sides. These abstractions allow code to be written for both gdb and gdbserver, for instance in the gdb/arch sub-directory. However, having two different abstractions is impractical. If some common code has a regcache, and wants to use an operation defined on reg_buffer_common, it can't. It would be better to have just one. Change all instances of `regcache *` in gdbsupport/common-regcache.h to be `reg_buffer_common *`, then fix fallouts. Implementations in gdb and gdbserver now need to down-cast (using gdb::checked_static_cast) from reg_buffer_common to their concrete regcache type. Some of them could be avoided by changing free functions (like regcache_register_size) to be virtual methods on reg_buffer_common. I tried it, it seems to work, but I did not include it in this series to avoid adding unnecessary changes. Change-Id: Ia5503adb6b5509a0f4604bd2a68b4642cc5283fd Reviewed-by: John Baldwin <jhb@FreeBSD.org>
2023-12-12gdbserver/win32: fix crash on detachStefano Moioli1-1/+1
this patch fixes a crash in gdbserver whenever a process is detached. the crash is caused by `detach` calling `remove_process` before `win32_clear_inferiors` error message: Detaching from process 184 ../../gdbserver/inferiors.cc:160: A problem internal to GDBserver has been detec ted. remove_process: Assertion `find_thread_process (process) == NULL' failed. This application has requested the Runtime to terminate it in an unusual way. Please contact the application's support team for more information. Approved-By: Tom Tromey <tom@tromey.com>
2023-12-08gdbserver: allow for general 'monitor set debug COMPONENT VALUE' useAndrew Burgess1-32/+143
Building on the last commit, which added a general --debug=COMPONENT option to the gdbserver command line, this commit updates the monitor command to allow for general: (gdb) monitor set debug COMPONENT off|on style commands. Just like with the previous commit, the COMPONENT can be any one of all, threads, remote, event-loop, and correspond to the same set of global debug flags. While on the command line it is possible to do: --debug=remote,event-loop,threads the components have to be entered one at a time with the monitor command. I guess there's no reason why we couldn't allow component grouping within the monitor command, but (to me) what I have here seemed more in the spirit of GDB's existing 'set debug ...' commands. If people want it then we can always add component grouping later. Notice in the above that I use 'off' and 'on' instead of '0' and '1', which is what the 'monitor set debug' command used to use. The 0/1 can still be used, but I now advertise off/on in all the docs and help text, again, this feels more inline with GDB's existing boolean settings. I have removed the two existing monitor commands: monitor set remote-debug 0|1 monitor set event-loop-debug 0|1 These are replaced by: monitor set debug remote off|on monitor set debug event-loop off|on respectively. Approved-By: Tom Tromey <tom@tromey.com> Reviewed-By: Eli Zaretskii <eliz@gnu.org>
2023-12-08gdbserver: allow the --debug command line option to take a valueAndrew Burgess1-8/+150
Currently, gdbserver has the following command line options related to debugging output: --debug --remote-debug --event-loop-debug This doesn't scale well. If I want an extra debug component I need to add another command line flag. This commit changes --debug to take a list of components. The currently supported components are: all, threads, remote, and event-loop. The 'threads' component represents the debug we currently get from the --debug option. And if --debug is used without a component list then the threads component is assumed as the default. Currently the threads component actually includes a lot of output that is not really threads related. In the future I'd like to split this up into some new, separate components. But that is not part of this commit, or even this series. The special component 'all' does what you'd expect: enables debug output from all supported components. The component list is parsed left to write, and you can prefix a component with '-' to disable that component, so I can write: target> gdbserver --debug=all,-event-loop to get debug for all components except the event-loop component. I've removed the existing --remote-debug and --event-loop-debug command line options, these are equivalent to --debug=remote and --debug=event-loop respectively, or --debug=remote,event-loop to enable both components. In this commit I've only update the command line options, in the next commit I'll update the monitor commands to support a similar interface. Reviewed-By: Eli Zaretskii <eliz@gnu.org> Approved-By: Tom Tromey <tom@tromey.com>