OpenE2K/qemu-e2k
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qemu-e2k/util
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Emilio Cota 1ff4a81bd3 tcg: use QTree instead of GTree 
qemu-user can hang in a multi-threaded fork. One common
reason is that when creating a TB, between fork and exec
we manipulate a GTree whose memory allocator (GSlice) is
not fork-safe.

Although POSIX does not mandate it, the system's allocator
(e.g. tcmalloc, libc malloc) is probably fork-safe.

Fix some of these hangs by using QTree, which uses the system's
allocator regardless of the Glib version that we used at
configuration time.

Tested with the test program in the original bug report, i.e.:
```

void garble() {
  int pid = fork();
  if (pid == 0) {
    exit(0);
  } else {
    int wstatus;
    waitpid(pid, &wstatus, 0);
  }
}

void supragarble(unsigned depth) {
  if (depth == 0)
    return ;

  std::thread a(supragarble, depth-1);
  std::thread b(supragarble, depth-1);
  garble();
  a.join();
  b.join();
}

int main() {
  supragarble(10);
}
```

Resolves: https://gitlab.com/qemu-project/qemu/-/issues/285
Reported-by: Valentin David <me@valentindavid.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Emilio Cota <cota@braap.org>
Message-Id: <20230205163758.416992-3-cota@braap.org>
[rth: Add QEMU_DISABLE_CFI for all callback using functions.]
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2023-03-28 15:23:10 -07:00
..
aio-posix.c aio: make aio_set_fd_poll() static to aio-posix.c 2023-03-13 15:23:37 +04:00
aio-posix.h aio-posix: fix spurious ->poll_ready() callbacks in main loop 2022-03-17 11:23:18 +00:00
aio-wait.c aio_wait_kick: add missing memory barrier 2022-06-24 17:07:06 +02:00
aio-win32.c win32: avoid mixing SOCKET and file descriptor space 2023-03-13 15:39:31 +04:00
aiocb.c
async-teardown.c Fix non-first inclusions of qemu/osdep.h 2023-02-08 07:28:05 +01:00
async.c async: clarify usage of barriers in the polling case 2023-03-07 12:39:53 +01:00
atomic64.c osdep: Move memalign-related functions to their own header 2022-03-07 13:16:49 +00:00
base64.c
bitmap.c migration: Use non-atomic ops for clear log bitmap 2022-11-21 11:58:10 +01:00
bitops.c replace TABs with spaces 2023-03-20 12:43:50 +01:00
block-helpers.c
block-helpers.h
buffer.c
bufferiszero.c include/qemu/cpuid: Introduce xgetbv_low 2023-03-05 13:44:07 -08:00
cacheflush.c util/cacheflush: fix cache on windows-arm64 2023-02-21 08:53:03 -10:00
compatfd.c util: replace pipe()+cloexec with g_unix_open_pipe() 2022-05-03 15:18:14 +04:00
coroutine-sigaltstack.c Remove qemu-common.h include from most units 2022-04-06 14:31:55 +02:00
coroutine-ucontext.c coroutine-ucontext: use QEMU_DEFINE_STATIC_CO_TLS() 2022-05-04 15:55:23 +02:00
coroutine-win32.c coroutine-win32: use QEMU_DEFINE_STATIC_CO_TLS() 2022-05-04 15:55:23 +02:00
crc32c.c
crc-ccitt.c
cutils.c util: remove support for hex numbers with a scaling suffix 2023-01-06 00:51:02 +01:00
dbus.c
drm.c
envlist.c replace TABs with spaces 2023-03-20 12:43:50 +01:00
error-report.c util/error: add G_GNUC_PRINTF for various functions 2023-01-11 10:44:34 +01:00
error.c error: add global &error_warn destination 2023-03-13 15:23:37 +04:00
event_notifier-posix.c Replace qemu_pipe() with g_unix_open_pipe() 2022-05-03 15:17:56 +04:00
event_notifier-win32.c Remove qemu-common.h include from most units 2022-04-06 14:31:55 +02:00
fdmon-epoll.c aio-posix: fix race between epoll upgrade and aio_set_fd_handler() 2023-03-27 15:12:17 +02:00
fdmon-io_uring.c aio-posix: fix build failure io_uring 2.2 2022-03-17 11:23:18 +00:00
fdmon-poll.c
fifo8.c
filemonitor-inotify.c
filemonitor-stub.c
getauxval.c
guest-random.c replay: Extract core API to 'exec/replay-core.h' 2023-02-27 22:29:01 +01:00
hbitmap.c hbitmap: fix hbitmap_status() return value for first dirty bit case 2023-02-17 14:34:24 +01:00
hexdump.c include: move C/util-related declarations to cutils.h 2022-04-06 14:31:43 +02:00
host-utils.c host-utils: Implemented signed 256-by-128 division 2022-06-20 08:38:58 -03:00
id.c
int128.c include/qemu/int128: Use Int128 structure for TCI 2023-02-04 06:19:42 -10:00
interval-tree.c util: Add interval-tree.c 2022-12-20 17:09:41 -08:00
iov.c util: make do_send_recv work with partial send/recv 2022-10-12 19:22:01 +04:00
iova-tree.c util: accept iova_tree_remove_parameter by value 2022-09-02 10:22:39 +08:00
keyval.c include: add qemu/keyval.h 2022-04-21 17:03:51 +04:00
lockcnt.c
log.c log: Remove unneeded new line 2023-03-08 00:37:48 +01:00
main-loop.c main-loop: remove qemu_fd_register(), win32/slirp/socket specific 2023-03-13 15:39:31 +04:00
memalign.c osdep: Move memalign-related functions to their own header 2022-03-07 13:16:49 +00:00
memfd.c
meson.build util: import GTree as QTree 2023-03-28 15:23:10 -07:00
mmap-alloc.c util/mmap-alloc: Remove qemu_mempath_getpagesize() 2022-08-26 13:34:21 +02:00
module.c module: add Error arguments to module_load and module_load_qom 2022-11-06 09:48:50 +01:00
notify.c
nvdimm-utils.c
osdep.c error handling: Use RETRY_ON_EINTR() macro where applicable 2023-01-09 13:50:47 +01:00
oslib-posix.c util: drop qemu_fork() 2023-03-13 15:23:37 +04:00
oslib-win32.c win32: add qemu_close_socket_osfhandle() 2023-03-21 11:16:03 +04:00
path.c
qdist.c
qemu-co-shared-resource.c
qemu-co-timeout.c util: add qemu-co-timeout 2022-06-29 10:56:12 +03:00
qemu-config.c error: Drop superfluous #include "qapi/qmp/qerror.h" 2023-02-23 13:56:14 +01:00
qemu-coroutine-io.c Remove qemu-common.h include from most units 2022-04-06 14:31:55 +02:00
qemu-coroutine-lock.c qemu-coroutine-lock: add smp_mb__after_rmw() 2023-03-07 12:39:53 +01:00
qemu-coroutine-sleep.c coroutine: Clean up superfluous inclusion of qemu/coroutine.h 2023-01-19 10:18:28 +01:00
qemu-coroutine.c coroutine: Clean up superfluous inclusion of qemu/coroutine.h 2023-01-19 10:18:28 +01:00
qemu-option.c
qemu-print.c
qemu-progress.c include: move progress API to qemu-progress.h 2022-04-06 14:31:43 +02:00
qemu-sockets.c win32: replace closesocket() with close() wrapper 2023-03-13 15:39:31 +04:00
qemu-thread-common.h
qemu-thread-posix.c qemu-thread-posix: cleanup, fix, document QemuEvent 2023-03-07 12:38:40 +01:00
qemu-thread-win32.c qemu-thread-win32: cleanup, fix, document QemuEvent 2023-03-07 12:38:40 +01:00
qemu-timer-common.c
qemu-timer.c qemu-timer: Skip empty timer lists before locking in qemu_clock_deadline_ns_all 2022-06-21 09:24:34 -07:00
qht.c util/qht: use striped locks under TSAN 2023-02-02 11:48:20 +00:00
qsp.c
qtree.c tcg: use QTree instead of GTree 2023-03-28 15:23:10 -07:00
range.c
rcu.c rcu: use coroutine TLS macros 2022-03-04 18:14:40 +01:00
readline.c readline: Extract readline_add_completion_of() from monitor 2023-02-04 07:56:54 +01:00
selfmap.c
stats64.c
sys_membarrier.c
systemd.c
thread-context.c qapi: Use returned bool to check for failure (again) 2022-12-14 16:19:35 +01:00
thread-pool.c thread-pool: remove stopping variable 2022-05-25 21:26:26 +02:00
throttle.c
timed-average.c
trace-events util/userfaultfd: Support /dev/userfaultfd 2023-02-11 16:51:09 +01:00
trace.h
transactions.c
unicode.c
uri.c Updated the FSF address to <https://www.gnu.org/licenses/> 2023-02-27 09:15:39 +01:00
userfaultfd.c util/userfaultfd: Support /dev/userfaultfd 2023-02-11 16:51:09 +01:00
uuid.c
vfio-helpers.c error handling: Use RETRY_ON_EINTR() macro where applicable 2023-01-09 13:50:47 +01:00
vhost-user-server.c block/export: only acquire AioContext once for vhost_user_server_stop() 2023-03-27 13:46:30 +02:00
yank.c