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2024-03-26gdb, gdbserver, gdbsupport: remove includes of early headersSimon Marchi1-1/+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>
2024-01-12Update copyright year range in header of all files managed by GDBAndrew Burgess1-1/+1
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.
2023-01-01Update copyright year range in header of all files managed by GDBJoel Brobecker1-1/+1
This commit is the result of running the gdb/copyright.py script, which automated the update of the copyright year range for all source files managed by the GDB project to be updated to include year 2023.
2022-11-28gdbserver: switch to right process in find_one_threadSimon Marchi1-12/+17
New in this version: add a dedicated test. When I do this: $ ./gdb -nx --data-directory=data-directory -q \ /bin/sleep \ -ex "maint set target-non-stop on" \ -ex "tar ext :1234" \ -ex "set remote exec-file /bin/sleep" \ -ex "run 1231 &" \ -ex add-inferior \ -ex "inferior 2" Reading symbols from /bin/sleep... (No debugging symbols found in /bin/sleep) Remote debugging using :1234 Starting program: /bin/sleep 1231 Reading /lib64/ld-linux-x86-64.so.2 from remote target... warning: File transfers from remote targets can be slow. Use "set sysroot" to access files locally instead. Reading /lib64/ld-linux-x86-64.so.2 from remote target... Reading /usr/lib/debug/.build-id/a6/7a1408f18db3576757eea210d07ba3fc560dff.debug from remote target... [New inferior 2] Added inferior 2 on connection 1 (extended-remote :1234) [Switching to inferior 2 [<null>] (<noexec>)] (gdb) Reading /lib/x86_64-linux-gnu/libc.so.6 from remote target... attach 3659848 Attaching to process 3659848 /home/smarchi/src/binutils-gdb/gdb/thread.c:85: internal-error: inferior_thread: Assertion `current_thread_ != nullptr' failed. Note the "attach" command just above. When doing it on the command-line with a -ex switch, the bug doesn't trigger. The internal error of GDB is actually caused by GDBserver crashing, and the error recovery of GDB is not on point. This patch aims to fix just the GDBserver crash, not the GDB problem. GDBserver crashes with a segfault here: (gdb) bt #0 0x00005555557fb3f4 in find_one_thread (ptid=...) at /home/smarchi/src/binutils-gdb/gdbserver/thread-db.cc:177 #1 0x00005555557fd5cf in thread_db_thread_handle (ptid=<error reading variable: Cannot access memory at address 0xffffffffffffffa0>, handle=0x7fffffffc400, handle_len=0x7fffffffc3f0) at /home/smarchi/src/binutils-gdb/gdbserver/thread-db.cc:461 #2 0x000055555578a0b6 in linux_process_target::thread_handle (this=0x5555558a64c0 <the_x86_target>, ptid=<error reading variable: Cannot access memory at address 0xffffffffffffffa0>, handle=0x7fffffffc400, handle_len=0x7fffffffc3f0) at /home/smarchi/src/binutils-gdb/gdbserver/linux-low.cc:6905 #3 0x00005555556dfcc6 in handle_qxfer_threads_worker (thread=0x60b000000510, buffer=0x7fffffffc8a0) at /home/smarchi/src/binutils-gdb/gdbserver/server.cc:1645 #4 0x00005555556e00e6 in operator() (__closure=0x7fffffffc5e0, thread=0x60b000000510) at /home/smarchi/src/binutils-gdb/gdbserver/server.cc:1696 #5 0x00005555556f54be in for_each_thread<handle_qxfer_threads_proper(buffer*)::<lambda(thread_info*)> >(struct {...}) (func=...) at /home/smarchi/src/binutils-gdb/gdbserver/gdbthread.h:159 #6 0x00005555556e0242 in handle_qxfer_threads_proper (buffer=0x7fffffffc8a0) at /home/smarchi/src/binutils-gdb/gdbserver/server.cc:1694 #7 0x00005555556e04ba in handle_qxfer_threads (annex=0x629000000213 "", readbuf=0x621000019100 '\276' <repeats 200 times>..., writebuf=0x0, offset=0, len=4097) at /home/smarchi/src/binutils-gdb/gdbserver/server.cc:1732 #8 0x00005555556e1989 in handle_qxfer (own_buf=0x629000000200 "qXfer:threads", packet_len=26, new_packet_len_p=0x7fffffffd630) at /home/smarchi/src/binutils-gdb/gdbserver/server.cc:2045 #9 0x00005555556e720a in handle_query (own_buf=0x629000000200 "qXfer:threads", packet_len=26, new_packet_len_p=0x7fffffffd630) at /home/smarchi/src/binutils-gdb/gdbserver/server.cc:2685 #10 0x00005555556f1a01 in process_serial_event () at /home/smarchi/src/binutils-gdb/gdbserver/server.cc:4176 #11 0x00005555556f4457 in handle_serial_event (err=0, client_data=0x0) at /home/smarchi/src/binutils-gdb/gdbserver/server.cc:4514 #12 0x0000555555820f56 in handle_file_event (file_ptr=0x607000000250, ready_mask=1) at /home/smarchi/src/binutils-gdb/gdbsupport/event-loop.cc:573 #13 0x0000555555821895 in gdb_wait_for_event (block=1) at /home/smarchi/src/binutils-gdb/gdbsupport/event-loop.cc:694 #14 0x000055555581f533 in gdb_do_one_event (mstimeout=-1) at /home/smarchi/src/binutils-gdb/gdbsupport/event-loop.cc:264 #15 0x00005555556ec9fb in start_event_loop () at /home/smarchi/src/binutils-gdb/gdbserver/server.cc:3512 #16 0x00005555556f0769 in captured_main (argc=4, argv=0x7fffffffe0d8) at /home/smarchi/src/binutils-gdb/gdbserver/server.cc:3992 #17 0x00005555556f0e3f in main (argc=4, argv=0x7fffffffe0d8) at /home/smarchi/src/binutils-gdb/gdbserver/server.cc:4078 The reason is a wrong current process when find_one_thread is called. The current process is the 2nd one, which was just attached. It does not yet have thread_db data (proc->priv->thread_db is nullptr). As we iterate on all threads of all process to fulfull the qxfer:threads:read request, we get to a thread of process 1 for which we haven't read thread_db information yet (lwp_info::thread_known is false), so we get into find_one_thread. find_one_thread uses `current_process ()->priv->thread_db`, assuming the current process matches the ptid passed as a parameter, which is wrong. A segfault happens when trying to dereference that thread_db pointer. Fix this by making find_one_thread not assume what the current process / current thread is. If it needs to call into libthread_db, which we know will try to read memory from the current process, then temporarily set the current process. In the case where the thread is already know and we return early, we don't need to switch process. Add a test to reproduce this specific situation. Change-Id: I09b00883e8b73b7e5f89d0f47cb4e9c0f3d6caaa Approved-By: Andrew Burgess <aburgess@redhat.com>
2022-01-18gdbserver: introduce threads_debug_printf, THREADS_SCOPED_DEBUG_ENTER_EXITSimon Marchi1-27/+17
Add the threads_debug_printf and THREADS_SCOPED_DEBUG_ENTER_EXIT, which use the logging infrastructure from gdbsupport/common-debug.h. Replace all debug_print uses that are predicated by debug_threads with threads_dethreads_debug_printf. Replace uses of the debug_enter and debug_exit macros with THREADS_SCOPED_DEBUG_ENTER_EXIT, which serves essentially the same purpose, but allows showing what comes between the enter and the exit in an indented form. Note that "threads" debug is currently used for a bit of everything in GDBserver, not only threads related stuff. It should ideally be cleaned up and separated logically as is done in GDB, but that's out of the scope of this patch. Change-Id: I2d4546464462cb4c16f7f1168c5cec5a89f2289a
2022-01-01Automatic Copyright Year update after running gdb/copyright.pyJoel Brobecker1-1/+1
This commit brings all the changes made by running gdb/copyright.py as per GDB's Start of New Year Procedure. For the avoidance of doubt, all changes in this commits were performed by the script.
2021-12-13gdbserver: replace direct assignments to current_threadTankut Baris Aktemur1-9/+5
Replace the direct assignments to current_thread with switch_to_thread. Use scoped_restore_current_thread when appropriate. There is one instance remaining in linux-low.cc's wait_for_sigstop. This will be handled in a separate patch. Regression-tested on X86-64 Linux using the native-gdbserver and native-extended-gdbserver board files.
2021-09-23Remove defaulted 'tid' parameter to ptid_t constructorTom Tromey1-1/+1
I wanted to find, and potentially modify, all the spots where the 'tid' parameter to the ptid_t constructor was used. So, I temporarily removed this parameter and then rebuilt. In order to make it simpler to search through the "real" (nonzero) uses of this parameter, something I knew I'd have to do multiple times, I removed any ", 0" from constructor calls. Co-Authored-By: John Baldwin <jhb@FreeBSD.org>
2021-01-01Update copyright year range in all GDB filesJoel Brobecker1-1/+1
This commits the result of running gdb/copyright.py as per our Start of New Year procedure... gdb/ChangeLog Update copyright year range in copyright header of all GDB files.
2020-07-22gdbserver: handle running threads in qXfer:threads:readPedro Alves1-8/+0
On some systems, the gdb.multi/multi-target.exp testcase occasionally fails like so: Running src/gdb/testsuite/gdb.multi/multi-target.exp ... FAIL: gdb.multi/multi-target.exp: info-inferiors: multi_process=on: inferior 1: info connections FAIL: gdb.multi/multi-target.exp: info-inferiors: multi_process=on: inferior 1: info inferiors FAIL: gdb.multi/multi-target.exp: info-inferiors: multi_process=on: inferior 2: info connections FAIL: gdb.multi/multi-target.exp: info-inferiors: multi_process=on: inferior 2: info inferiors FAIL: gdb.multi/multi-target.exp: info-inferiors: multi_process=on: inferior 3: inferior 3 ... many more cascading fails. The problem starts when the testcase runs an inferior against GDBserver: (gdb) run Starting program: build/gdb/testsuite/outputs/gdb.multi/multi-target/multi-target Reading /lib64/ld-linux-x86-64.so.2 from remote target... warning: File transfers from remote targets can be slow. Use "set sysroot" to access files locally instead. Reading /lib64/ld-linux-x86-64.so.2 from remote target... Reading /lib64/ld-2.31.so from remote target... Reading /lib64/.debug/ld-2.31.so from remote target... Reading /usr/lib/debug//lib64/ld-2.31.so from remote target... Reading /usr/lib/debug/lib64//ld-2.31.so from remote target... Reading target:/usr/lib/debug/lib64//ld-2.31.so from remote target... Reading /lib/x86_64-linux-gnu/libpthread.so.0 from remote target... Reading /lib/x86_64-linux-gnu/libc.so.6 from remote target... Reading /lib/x86_64-linux-gnu/libc-2.31.so from remote target... Reading /lib/x86_64-linux-gnu/.debug/libc-2.31.so from remote target... Reading /usr/lib/debug//lib/x86_64-linux-gnu/libc-2.31.so from remote target... Reading /usr/lib/debug//lib/x86_64-linux-gnu/libc-2.31.so from remote target... Remote connection closed ... Note the "Remote connection closed" message. That means GDBserver exited abruptly. I traced it down to the fact that GDB fetches the thread list from GDBserver while the main thread of the process is still running. On my main system where I wrote the testcase, I have not observed the failure because it is slow enough that the thread stops before GDBserver fetches the thread list in the problem scenario which I'll describe below. With some --remote-debug logging from GDBserver side, we see the last packets before the connection closes: ... getpkt ("vCont;c"); [no ack sent] putpkt ("$OK#9a"); [noack mode] getpkt ("Tp10f9a.10f9a"); [no ack sent] putpkt ("$OK#9a"); [noack mode] getpkt ("Hgp0.0"); [no ack sent] putpkt ("$OK#9a"); [noack mode] getpkt ("qXfer:threads:read::0,1000"); [no ack sent] Note the vCont;c , which sets the program running, and then a qXfer:threads:read packet at the end. The problem happens when the thread list refresh (qXfer:threads:read) is sent just while the main thread is running and it still hasn't initialized its libpthread id internally. In that state, the main thread's lwp will remain with the thread_known flag clear. See in find_one_thread: /* If the new thread ID is zero, a final thread ID will be available later. Do not enable thread debugging yet. */ if (ti.ti_tid == 0) return 0; Now, back in server.cc, to handle the qXfer:threads:read, we reach handle_qxfer_threads -> handle_qxfer_threads_proper, and the latter then calls handle_qxfer_threads_worker for each known thread. In handle_qxfer_threads_worker, we call target_thread_handle. This ends up in thread_db_thread_handle, here: if (!lwp->thread_known && !find_one_thread (thread->id)) return false; Since the thread ID isn't known yet, we call find_one_thread. This calls into libthread_db.so, which accesses memory. Because the current thread is running, that fails and we throw an error, here: /* Get information about this thread. */ err = thread_db->td_ta_map_lwp2thr_p (thread_db->thread_agent, lwpid, &th); if (err != TD_OK) error ("Cannot get thread handle for LWP %d: %s", lwpid, thread_db_err_str (err)); The current design is that whenever GDB-facing packets/requests need to accesses memory, server.cc is supposed to prepare the target for the access. See gdb_read_memory / gdb_write_memory. This preparation means pausing threads if in non-stop mode (someday we could lift this requirement, but we will still need to pause to access registers or do other related ptrace accesses like PTRACE_GET_THREAD_AREA). Note that the multi-target.exp testcase forces "maint set target-non-stop on". So the fix here is to prepare the target to access memory when handling qXfer:threads:read too. gdbserver/ChangeLog: * inferiors.cc (switch_to_process): New, moved here from thread-db.cc, and made extern. * inferiors.h (switch_to_process): Declare. * server.cc: Include "gdbsupport/scoped_restore.h". (handle_qxfer_threads_proper): Now returns bool. Prepare to access memory around target calls. (handle_qxfer_threads): Handle errors. * thread-db.cc (switch_to_process): Moved to inferiors.cc.
2020-04-02gdbserver/linux-low: turn process/thread addition/deletion ops into methodsTankut Baris Aktemur1-1/+1
gdbserver/ChangeLog: 2020-04-02 Tankut Baris Aktemur <tankut.baris.aktemur@intel.com> Turn the 'new_process', 'delete_process', 'new_thread', 'delete_thread', and 'new_fork' linux target ops into methods of linux_process_target. * linux-low.h (struct linux_target_ops): Remove the ops. (class linux_process_target) <add_linux_process> <add_lwp> <delete_lwp> <attach_lwp> <detach_one_lwp> <check_zombie_leaders> <filter_exit_event> <low_new_process> <low_delete_process> <low_new_thread> <low_delete_thread> <low_new_fork>: Declare. * linux-low.cc (delete_lwp): Turn into... (linux_process_target::delete_lwp): ...this. (linux_process_target::low_delete_thread): Define. (linux_add_process): Turn into... (linux_process_target::add_linux_process): ...this. (linux_process_target::low_new_process): Define. (linux_process_target::low_delete_process): Define. (linux_process_target::low_new_fork): Define. (add_lwp): Turn into... (linux_process_target::add_lwp): ...this. (linux_process_target::low_new_thread): Define. (linux_attach_lwp): Turn into... (linux_process_target::attach_lwp): ...this. (linux_detach_one_lwp): Turn into... (linux_process_target::detach_one_lwp): ...this. (linux_detach_lwp_callback): Remove and inline... (linux_process_target::detach): ...here. (check_zombie_leaders): Turn into... (linux_process_target::check_zombie_leaders): ...this. (filter_exit_event): Turn into... (linux_process_target::filter_exit_event): ...this. Update the callers below. (linux_process_target::handle_extended_wait) (linux_process_target::create_inferior) (attach_proc_task_lwp_callback) (linux_process_target::attach) (linux_process_target::detach) (linux_process_target::mourn) * thread-db.cc (attach_thread) * linux-x86-low.cc (class x86_target) <low_new_process> <low_delete_process> <low_new_thread> <low_delete_thread> <low_new_fork>: Declare. (x86_linux_new_process): Turn into... (x86_target::low_new_process): ...this. (x86_linux_delete_process): Turn into... (x86_target::low_delete_process): ...this. (x86_target::low_new_thread): Define. (x86_target::low_delete_thread): Define. (x86_linux_new_fork): Turn into... (x86_target::low_new_fork): ...this. (the_low_target): Remove the op fields. * linux-aarch64-low.cc (class aarch64_target) <low_new_process> <low_delete_process> <low_new_thread> <low_delete_thread> <low_new_fork>: Declare. (aarch64_linux_new_process): Turn into... (aarch64_target::low_new_process): ...this. (aarch64_linux_delete_process): Turn into... (aarch64_target::low_delete_process): ...this. (aarch64_target::low_new_thread): Define. (aarch64_target::low_delete_thread): Define. (aarch64_linux_new_fork): Turn into... (aarch64_target::low_new_fork): ...this. (the_low_target): Remove the op fields. * linux-arm-low.cc (class arm_target) <low_new_process> <low_delete_process> <low_new_thread> <low_delete_thread> <low_new_fork>: Declare. (arm_new_process): Turn into... (arm_target::low_new_process): ...this. (arm_delete_process): Turn into... (arm_target::low_delete_process): ...this. (arm_new_thread): Turn into... (arm_target::low_new_thread): ...this. (arm_delete_thread): Turn into... (arm_target::low_delete_thread): ...this. (arm_new_fork): Turn into... (arm_target::low_new_fork): ...this. (the_low_target): Remove the op fields. * linux-mips-low.cc (class mips_target) <low_new_process> <low_delete_process> <low_new_thread> <low_delete_thread> <low_new_fork>: Declare. (mips_linux_new_process): Turn into... (mips_target::low_new_process): ...this. (mips_linux_delete_process): Turn into... (mips_target::low_delete_process): ...this. (mips_linux_new_thread): Turn into... (mips_target::low_new_thread): ...this. (mips_linux_delete_thread): Turn into... (mips_target::low_delete_thread): ...this. (mips_linux_new_fork): Turn into... (mips_target::low_new_fork): ...this. (the_low_target): Remove the op fields. * linux-bfin-low.cc (the_low_target): Remove the op fields. * linux-crisv32-low.cc (the_low_target): Ditto. * linux-m32r-low.cc (the_low_target): Ditto. * linux-m68k-low.cc (the_low_target): Ditto. * linux-ppc-low.cc (the_low_target): Ditto. * linux-s390-low.cc (the_low_target): Ditto. * linux-sh-low.cc (the_low_target): Ditto. * linux-tic6x-low.cc (the_low_target): Ditto. * linux-tile-low.cc (the_low_target): Ditto. * linux-xtensa-low.cc (the_low_target): Ditto.
2020-02-13gdbserver: rename source files to .ccSimon Marchi1-0/+910
For the same reasons outlined in the previous patch, this patch renames gdbserver source files to .cc. I have moved the "-x c++" switch to only those rules that require it. gdbserver/ChangeLog: * Makefile.in: Rename source files from .c to .cc. * %.c: Rename to %.cc. * configure.ac: Rename server.c to server.cc. * configure: Re-generate.
generated by cgit v1.1 at 2024-09-07 19:54:23 +0000