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bug#36609: 27.0.50; Possible race-condition in threading implementation
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From: |
Pip Cet |
|
Subject: |
bug#36609: 27.0.50; Possible race-condition in threading implementation |
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Date: |
Fri, 12 Jul 2019 13:40:15 +0000 |
On Fri, Jul 12, 2019 at 12:55 PM Eli Zaretskii <eliz@gnu.org> wrote:
> > From: Pip Cet <pipcet@gmail.com>
> > Date: Fri, 12 Jul 2019 12:44:35 +0000
> > Cc: 36609@debbugs.gnu.org
> >
> > Okay, I'm still not sure this is really the problem Andreas was
> > seeing, but this code fails to work with xg_select:
> >
> > (let ((thread (make-thread (lambda ()
> > (sleep-for 3)))))
> > (thread-yield)
> > (thread-signal thread 'error nil))
>
> What do you mean by "fails"? What do you see when you eval this?
With `emacs -Q', a blinking cursor and an unresponsive emacs (no
response to key presses, not even triple C-g). Sometimes, at least.
Here's a full backtrace of a session where the hang did happen:
Thread 4 (Thread 0x7fffeeb8a700 (LWP 26117)):
#0 0x00007ffff4967819 in __GI___poll (fds=0xd93070, nfds=1, timeout=-1)
at ../sysdeps/unix/sysv/linux/poll.c:29
resultvar = 18446744073709551100
sc_cancel_oldtype = 0
#1 0x00007ffff698e136 in () at /lib/x86_64-linux-gnu/libglib-2.0.so.0
#2 0x00007ffff698e25c in g_main_context_iteration ()
at /lib/x86_64-linux-gnu/libglib-2.0.so.0
#3 0x00007fffeebd7ffd in ()
at /usr/lib/x86_64-linux-gnu/gio/modules/libdconfsettings.so
#4 0x00007ffff69b6415 in () at /lib/x86_64-linux-gnu/libglib-2.0.so.0
#5 0x00007ffff4b38fa3 in start_thread (arg=<optimized out>)
at pthread_create.c:486
ret = <optimized out>
pd = <optimized out>
now = <optimized out>
unwind_buf = {
cancel_jmp_buf = {{
jmp_buf = {140737198466816, -2332898995959237690,
140737488337566, 140737488337567, 140737198466816, 13933232,
2332932536188793798, 2332875456844002246},
mask_was_saved = 0
}},
priv = {
pad = {0x0, 0x0, 0x0, 0x0},
data = {
prev = 0x0,
cleanup = 0x0,
canceltype = 0
}
}
}
not_first_call = <optimized out>
#6 0x00007ffff49724cf in clone () at
../sysdeps/unix/sysv/linux/x86_64/clone.S:95
Thread 3 (Thread 0x7fffef59e700 (LWP 26116)):
#0 0x00007ffff4967819 in __GI___poll (fds=0xcb7a20, nfds=2, timeout=-1)
at ../sysdeps/unix/sysv/linux/poll.c:29
resultvar = 18446744073709551100
sc_cancel_oldtype = 0
#1 0x00007ffff698e136 in () at /lib/x86_64-linux-gnu/libglib-2.0.so.0
#2 0x00007ffff698e4c2 in g_main_loop_run ()
at /lib/x86_64-linux-gnu/libglib-2.0.so.0
#3 0x00007ffff6bba0d6 in () at /lib/x86_64-linux-gnu/libgio-2.0.so.0
#4 0x00007ffff69b6415 in () at /lib/x86_64-linux-gnu/libglib-2.0.so.0
#5 0x00007ffff4b38fa3 in start_thread (arg=<optimized out>)
at pthread_create.c:486
ret = <optimized out>
pd = <optimized out>
now = <optimized out>
unwind_buf = {
cancel_jmp_buf = {{
jmp_buf = {140737209034496, -2332898995959237690,
140737488336926, 140737488336927, 140737209034496, 13323152,
2332932821804118982, 2332875456844002246},
mask_was_saved = 0
}},
priv = {
pad = {0x0, 0x0, 0x0, 0x0},
data = {
prev = 0x0,
cleanup = 0x0,
canceltype = 0
}
}
}
not_first_call = <optimized out>
#6 0x00007ffff49724cf in clone () at
../sysdeps/unix/sysv/linux/x86_64/clone.S:95
Thread 2 (Thread 0x7ffff017d700 (LWP 26115)):
#0 0x00007ffff4967819 in __GI___poll (fds=0xb400d0, nfds=1, timeout=-1)
at ../sysdeps/unix/sysv/linux/poll.c:29
resultvar = 18446744073709551100
sc_cancel_oldtype = 0
#1 0x00007ffff698e136 in () at /lib/x86_64-linux-gnu/libglib-2.0.so.0
#2 0x00007ffff698e25c in g_main_context_iteration ()
at /lib/x86_64-linux-gnu/libglib-2.0.so.0
#3 0x00007ffff698e2a1 in () at /lib/x86_64-linux-gnu/libglib-2.0.so.0
#4 0x00007ffff69b6415 in () at /lib/x86_64-linux-gnu/libglib-2.0.so.0
#5 0x00007ffff4b38fa3 in start_thread (arg=<optimized out>)
at pthread_create.c:486
ret = <optimized out>
pd = <optimized out>
now = <optimized out>
unwind_buf = {
cancel_jmp_buf = {{
jmp_buf = {140737221482240, -2332898995959237690,
140737488347710, 140737488347711, 140737221482240, 0,
2332865253915489222, 2332875456844002246},
mask_was_saved = 0
}},
priv = {
pad = {0x0, 0x0, 0x0, 0x0},
data = {
prev = 0x0,
cleanup = 0x0,
canceltype = 0
}
}
}
not_first_call = <optimized out>
#6 0x00007ffff49724cf in clone () at
../sysdeps/unix/sysv/linux/x86_64/clone.S:95
Thread 1 (Thread 0x7ffff0e30e00 (LWP 26108)):
#0 0x00007ffff4b404c6 in pthread_sigmask
(how=2, newmask=<optimized out>, oldmask=0x0)
at ../sysdeps/unix/sysv/linux/pthread_sigmask.c:48
local_newmask = {
__val = {7, 17697270867008781056, 11498208, 5790296, 0,
140737488342800, 2, 0, 0, 0, 0, 0, 0, 0, 0, 6922490}
}
result = 0
#1 0x0000000000585a7d in restore_signal_mask (oldset=0x7fffffffcf10)
at sysdep.c:876
#2 0x0000000000699292 in really_call_select (arg=0x7fffffffd060) at
thread.c:584
sa = 0x7fffffffd060
self = 0xa745c0 <main_thread>
oldset = {
__val = {0, 5710159, 8192, 126116988112, 140737488344608,
140737298839344, 7, 0, 11381952, 0, 8192, 1562936528, 140737488342720,
5968906924941129, 0, 16538645}
}
#3 0x00000000005e5ee0 in flush_stack_call_func
(func=0x699239 <really_call_select>, arg=0x7fffffffd060) at alloc.c:4969
end = 0x7fffffffd020
self = 0xa745c0 <main_thread>
sentry = {
o = {
__max_align_ll = 0,
__max_align_ld = <invalid float value>
}
}
#4 0x0000000000699389 in thread_select
(func=0x419320 <pselect@plt>, max_fds=6, rfds=0x7fffffffd590,
wfds=0x7fffffffd510, efds=0x0, timeout=0x7fffffffd840, sigmask=0x0) at
thread.c:616
sa = {
func = 0x419320 <pselect@plt>,
max_fds = 6,
rfds = 0x7fffffffd590,
wfds = 0x7fffffffd510,
efds = 0x0,
timeout = 0x7fffffffd840,
sigmask = 0x0,
result = -157757095
}
#5 0x00000000006bfeac in xg_select
(fds_lim=6, rfds=0x7fffffffd8e0, wfds=0x7fffffffd860, efds=0x0,
timeout=0x7fffffffd840, sigmask=0x0) at xgselect.c:117
all_rfds = {
fds_bits = {32, 0 <repeats 15 times>}
}
all_wfds = {
fds_bits = {0 <repeats 16 times>}
}
tmo = {
tv_sec = 5621546,
tv_nsec = 15785445
}
tmop = 0x7fffffffd840
context = 0xc1c200
have_wfds = true
gfds_buf = {{
fd = 895,
events = 0,
revents = 0
}, {
fd = 0,
events = 0,
revents = 0
}, {
fd = 0,
events = 0,
revents = 0
}, {
fd = 8096,
events = 65535,
revents = 0
}, {
fd = 0,
events = 0,
revents = 0
}, {
fd = 0,
events = 0,
revents = 0
}, {
fd = 0,
events = 0,
revents = 0
}, {
fd = 0,
events = 0,
revents = 0
}, {
fd = 0,
events = 0,
revents = 0
}, {
fd = 0,
events = 0,
revents = 0
}, {
fd = 16,
events = 0,
revents = 0
}, {
fd = 0,
events = 0,
revents = 0
} <repeats 11 times>, {
fd = -2057698731,
events = 39706,
revents = 28662
}, {
fd = 3,
events = 0,
revents = 0
}, {
fd = -2057698731,
events = 39706,
revents = 28662
}, {
fd = -161788823,
events = 32767,
revents = 0
}, {
fd = -2057698731,
events = 39642,
revents = 28662
}, {
fd = -190624704,
events = 32767,
revents = 0
}, {
fd = 16,
events = 0,
revents = 0
}, {
fd = 0,
events = 0,
revents = 0
}, {
fd = -664,
events = 65535,
revents = 65535
}, {
fd = -504530176,
events = 22038,
revents = 62873
}, {
fd = 12553216,
events = 0,
revents = 0
}, {
fd = -1252392363,
events = 44399,
revents = 28662
}, {
fd = 32,
events = 0,
revents = 0
}, {
fd = 0,
events = 0,
revents = 0
}, {
fd = 0,
events = 0,
revents = 0
}, {
fd = 0,
events = 0,
revents = 0
}, {
fd = 12553216,
events = 0,
revents = 0
}, {
fd = -191458327,
events = 32767,
revents = 0
}, {
fd = -190624704,
events = 32767,
revents = 0
}, {
fd = 139264,
events = 0,
revents = 0
}, {
fd = 17472,
events = 0,
revents = 0
}, {
fd = -191893943,
events = 32767,
revents = 0
}, {
fd = 128,
events = 0,
revents = 0
}, {
fd = -191909562,
events = 32767,
revents = 0
}, {
fd = 48,
events = 0,
revents = 0
}, {
fd = 1,
events = 0,
revents = 0
}, {
fd = 7,
events = 0,
revents = 0
}, {
fd = 64,
events = 0,
revents = 0
}, {
fd = 4,
events = 32767,
revents = 0
}, {
fd = 11649056,
events = 0,
revents = 0
}, {
fd = 47,
events = 0,
revents = 0
}, {
fd = 96,
events = 0,
revents = 0
}, {
fd = -664,
events = 65535,
revents = 65535
}, {
fd = 1,
events = 0,
revents = 0
}, {
fd = 4,
events = 49,
revents = 0
}, {
fd = 0,
events = 0,
revents = 0
}, {
fd = 0,
events = 0,
revents = 0
}, {
fd = 91,
events = 110,
revents = 0
}, {
fd = 124,
events = 119,
revents = 0
}, {
fd = 0,
events = 0,
revents = 0
}, {
fd = 17456,
events = 0,
revents = 0
}, {
fd = -190624704,
events = 32767,
revents = 0
}, {
fd = 48,
events = 0,
revents = 0
}, {
fd = 2,
events = 0,
revents = 0
}, {
fd = -664,
events = 65535,
revents = 65535
}, {
fd = 0,
events = 0,
revents = 0
}, {
fd = 0,
events = 0,
revents = 0
}, {
fd = -191900310,
events = 32767,
revents = 0
}, {
fd = -664,
events = 65535,
revents = 65535
}, {
fd = 0,
events = 0,
revents = 0
}, {
fd = 48,
events = 0,
revents = 0
}, {
fd = 187264016,
events = 0,
revents = 0
}, {
fd = 11498208,
events = 0,
revents = 0
}, {
fd = 0,
events = 0,
revents = 0
}, {
fd = 0,
events = 0,
revents = 0
}, {
fd = -11392,
events = 32767,
revents = 0
}, {
fd = 5621546,
events = 0,
revents = 0
}, {
fd = 187264016,
events = 0,
revents = 0
}, {
fd = -11360,
events = 32767,
revents = 0
}, {
fd = 187280083,
events = 0,
revents = 0
}, {
fd = -11344,
events = 32767,
revents = 0
}, {
fd = 5622263,
events = 0,
revents = 0
}, {
fd = 0,
events = 0,
revents = 0
}, {
fd = 187280083,
events = 0,
revents = 0
}, {
fd = -11280,
events = 32767,
revents = 0
}, {
fd = 6170867,
events = 0,
revents = 0
}, {
fd = 0,
events = 0,
revents = 0
}, {
fd = 0,
events = 0,
revents = 0
}, {
fd = 5627325,
events = 0,
revents = 0
}, {
fd = 6,
events = 0,
revents = 0
}, {
fd = 1,
events = 0,
revents = 0
}, {
fd = 0,
events = 1,
revents = 0
}, {
fd = 11498208,
events = 0,
revents = 0
}, {
fd = 0,
events = 0,
revents = 0
}, {
fd = 0,
events = 0,
revents = 0
}, {
fd = -11232,
events = 32767,
revents = 0
}, {
fd = 5621546,
events = 0,
revents = 0
}, {
fd = -134398935,
events = 0,
revents = 0
}, {
fd = -11200,
events = 32767,
revents = 0
}, {
fd = 187280099,
events = 0,
revents = 0
}, {
fd = -11184,
events = 32767,
revents = 0
}, {
fd = 5622263,
events = 0,
revents = 0
}, {
fd = 0,
events = 0,
revents = 0
}, {
fd = 187280099,
events = 0,
revents = 0
}, {
fd = -11120,
events = 32767,
revents = 0
}, {
fd = 6170867,
events = 0,
revents = 0
}, {
fd = 0,
events = 0,
revents = 0
}, {
fd = 0,
events = 0,
revents = 0
}, {
fd = 5627325,
events = 0,
revents = 0
}, {
fd = 6,
events = 0,
revents = 0
}, {
fd = 1,
events = 0,
revents = 0
}, {
fd = 0,
events = 1,
revents = 0
}, {
fd = 11498208,
events = 0,
revents = 0
}, {
fd = 187280099,
events = 0,
revents = 0
}, {
fd = -11072,
events = 32767,
revents = 0
}, {
fd = 5622263,
events = 0,
revents = 0
}, {
fd = -11024,
events = 32767,
revents = 0
}, {
fd = -134398935,
events = 32767,
revents = 0
}, {
fd = -10944,
events = 32767,
revents = 0
}, {
fd = 15785445,
events = 0,
revents = 0
}, {
fd = -11016,
events = 32767,
revents = 0
}, {
fd = 5623097,
events = 0,
revents = 0
}, {
fd = 11498208,
events = 0,
revents = 0
}, {
fd = 0,
events = 0,
revents = 0
}, {
fd = 0,
events = 0,
revents = 0
}, {
fd = -10992,
events = 32767,
revents = 0
}}
gfds = 0x7fffffffd100
gfds_size = 128
n_gfds = -1
retval = 0
our_fds = 0
max_fds = 5
context_acquired = false
i = 0
nfds = 0
tmo_in_millisec = 0
must_free = 0
need_to_dispatch = false
#6 0x000000000066b757 in wait_reading_process_output
(time_limit=0, nsecs=0, read_kbd=-1, do_display=true,
wait_for_cell=XIL(0), wait_proc=0x0, just_wait_proc=0) at
process.c:5423
process_skipped = false
channel = 6
nfds = 1
Available = {
fds_bits = {32, 0 <repeats 15 times>}
}
Writeok = {
fds_bits = {0 <repeats 16 times>}
}
check_write = true
check_delay = 0
no_avail = false
xerrno = 11
proc = XIL(0xcf7c00)
timeout = {
tv_sec = 100000,
tv_nsec = 0
}
end_time = {
tv_sec = 0,
tv_nsec = 140737488345168
}
timer_delay = {
tv_sec = 0,
tv_nsec = -1
}
got_output_end_time = {
tv_sec = 0,
tv_nsec = -1
}
wait = FOREVER
got_some_output = -1
prev_wait_proc_nbytes_read = 0
retry_for_async = false
count = 4
now = {
tv_sec = 0,
tv_nsec = -1
}
#7 0x000000000056c31e in kbd_buffer_get_event
(kbp=0x7fffffffdbd8, used_mouse_menu=0x7fffffffe1bf, end_time=0x0)
at keyboard.c:3836
do_display = true
obj = XIL(0x14bfd3fb)
#8 0x0000000000568706 in read_event_from_main_queue
(end_time=0x0, local_getcjmp=0x7fffffffdf80, used_mouse_menu=0x7fffffffe1bf)
at keyboard.c:2138
c = XIL(0)
save_jump = {{
__jmpbuf = {0, 0, 0, 0, 0, 0, 0, 0},
__mask_was_saved = 0,
__saved_mask = {
__val = {0 <repeats 16 times>}
}
}}
kb = 0x55c9f7 <XSETCDR+28>
count = 3
#9 0x0000000000568970 in read_decoded_event_from_main_queue
(end_time=0x0, local_getcjmp=0x7fffffffdf80, prev_event=XIL(0),
used_mouse_menu=0x7fffffffe1bf) at keyboard.c:2202
nextevt = XIL(0x7fffffffde30)
frame = 0x0
terminal = 0x0
events =
{XIL(0x7fffffffddb0), make_fixnum(1422534), XIL(0xaf72e0),
XIL(0), XIL(0), XIL(0x7fffffffddb0), make_fixnum(1405386),
XIL(0x135b623), XIL(0x7fffffffddf0), make_fixnum(1420782),
XIL(0xaf72e0), XIL(0x100000000), XIL(0), XIL(0x7fffffffddf0),
make_fixnum(1405386), XIL(0)}
n = 0
#10 0x000000000056a002 in read_char
(commandflag=1, map=XIL(0xfbaa33), prev_event=XIL(0),
used_mouse_menu=0x7fffffffe1bf, end_time=0x0) at keyboard.c:2810
c = XIL(0)
jmpcount = 3
local_getcjmp = {{
__jmpbuf = {0, 2332898996579464134, 16538645, 48, 0, 0,
2332898994838827974, -2332899704998988858},
__mask_was_saved = 0,
__saved_mask = {
__val = {140737214405912, 0, 140737225904168, 11498208,
0, 0, 140737488347152, 5621546, 4032516088, 11498208, 0, 0,
140737488347200, 5621546, 12363987, 140737488347296}
}
}}
save_jump = {{
__jmpbuf = {0, 0, 140737224472304, 0, 0, 11529984, 5621546, 0},
__mask_was_saved = -8336,
__saved_mask = {
__val = {6254137, 140737231486936, 12884893472, 0,
31776, 140737224472304, 140737231486936, 5623453, 51539607552,
140737224472309, 140737224472304, 5632971, 11529984, 11529984, 0,
11498208}
}
}}
tem = XIL(0x7fffefa759f0)
save = XIL(0)
previous_echo_area_message = XIL(0)
also_record = XIL(0)
reread = false
recorded = false
polling_stopped_here = true
orig_kboard = 0xc863c0
#11 0x0000000000576842 in read_key_sequence
(keybuf=0x7fffffffe3a0, prompt=XIL(0), dont_downcase_last=false,
can_return_switch_frame=true, fix_current_buffer=true,
prevent_redisplay=false)
at keyboard.c:9124
interrupted_kboard = 0xc863c0
interrupted_frame = 0xf976a0
key = XIL(0xf97ac0)
used_mouse_menu = false
echo_local_start = 0
last_real_key_start = 0
keys_local_start = 0
new_binding = XIL(0xf97ac0)
count = 3
t = 0
echo_start = 0
keys_start = 0
current_binding = XIL(0xfbaa33)
first_unbound = 31
mock_input = 0
used_mouse_menu_history = {false <repeats 30 times>}
fkey = {
parent = XIL(0xbe3cd3),
map = XIL(0xbe3cd3),
start = 0,
end = 0
}
keytran = {
parent = XIL(0x7ffff0ae0eeb),
map = XIL(0x7ffff0ae0eeb),
start = 0,
end = 0
}
indec = {
parent = XIL(0xbe3cc3),
map = XIL(0xbe3cc3),
start = 0,
end = 0
}
shift_translated = false
delayed_switch_frame = XIL(0)
original_uppercase = XIL(0)
original_uppercase_position = -1
dummyflag = false
starting_buffer = 0x7ffff04576f0
fake_prefixed_keys = XIL(0)
first_event = XIL(0)
second_event = XIL(0)
#12 0x00000000005667ae in command_loop_1 () at keyboard.c:1348
cmd = XIL(0x7fffffffe4f0)
keybuf =
{XIL(0x7fffffffe420), XIL(0x7ffff0b08008), XIL(0x100000007),
XIL(0), XIL(0), XIL(0x80a0), XIL(0x11f), XIL(0xaff380), XIL(0xaff380),
XIL(0), XIL(0x7fffffffe440), XIL(0x617021), make_fixnum(1073741824),
XIL(0x7fffffffe460), XIL(0xaf72e0), XIL(0), XIL(0),
XIL(0x7fffffffe440), make_fixnum(1405386), XIL(0xf04576f5),
XIL(0x7fffffffe4a0), XIL(0x61729f), XIL(0xaf72e0), XIL(0), XIL(0),
XIL(0x7fffffffe480), make_fixnum(1405386), XIL(0xf04576f5),
XIL(0x7fffffffe4c0), make_fixnum(1591385)}
i = 0
prev_modiff = 0
prev_buffer = 0x0
already_adjusted = false
#13 0x0000000000611d61 in internal_condition_case
(bfun=0x566384 <command_loop_1>, handlers=XIL(0x90), hfun=0x565b7d
<cmd_error>) at eval.c:1351
val = make_fixnum(1405386)
c = 0xb99e70
#14 0x000000000056607a in command_loop_2 (ignore=XIL(0)) at keyboard.c:1091
val = XIL(0)
#15 0x000000000061161a in internal_catch
(tag=XIL(0xd140), func=0x566051 <command_loop_2>, arg=XIL(0)) at eval.c:1112
val = XIL(0x7fffffffe5c0)
c = 0xb94fd0
#16 0x000000000056601c in command_loop () at keyboard.c:1070
#17 0x0000000000565752 in recursive_edit_1 () at keyboard.c:714
count = 1
val = XIL(0x7fffffffe620)
#18 0x00000000005658d4 in Frecursive_edit () at keyboard.c:786
count = 0
buffer = XIL(0)
#19 0x0000000000563961 in main (argc=4, argv=0x7fffffffe878) at emacs.c:2086
stack_bottom_variable = 0x5e00
do_initial_setlocale = true
no_loadup = false
junk = 0x0
dname_arg = 0x0
ch_to_dir = 0x0
original_pwd = 0x0
dump_mode = 0x0
skip_args = 0
temacs = 0x0
attempt_load_pdump = true
rlim = {
rlim_cur = 10022912,
rlim_max = 18446744073709551615
}
sockfd = -1
i thr
Id Target Id Frame
* 1 Thread 0x7ffff0e30e00 (LWP 26108) "emacs" pthread_sigmask (how=0,
newmask=<optimized out>, oldmask=0x7fffffffcf10)
at ../sysdeps/unix/sysv/linux/pthread_sigmask.c:48
2 Thread 0x7ffff017d700 (LWP 26115) "gmain"
0x00007ffff4967819 in __GI___poll (fds=0xb400d0, nfds=1, timeout=-1)
at ../sysdeps/unix/sysv/linux/poll.c:29
3 Thread 0x7fffef59e700 (LWP 26116) "gdbus"
0x00007ffff4967819 in __GI___poll (fds=0xcb7a20, nfds=2, timeout=-1)
at ../sysdeps/unix/sysv/linux/poll.c:29
4 Thread 0x7fffeeb8a700 (LWP 26117) "dconf worker"
0x00007ffff4967819 in __GI___poll (fds=0xd93070, nfds=1, timeout=-1)
at ../sysdeps/unix/sysv/linux/poll.c:29
> > Proposed patch attached.
>
> As I said earlier, I don't think it's right to use stack unwinding at
> this level. (Did you try this in a -nw session?)
Sorry, I didn't see that email until after I'd sent mine. I did try
with an -nw session, now, but I really think thread_select should not
return abnormally.
> I'd appreciate a description of what you think happens here, and why.
When a thread is signalled (by thread-signal, which sets another
thread's error_symbol) while the signalled thread is inside a
select(), thread_select() will return non-locally for that thread, and
we fail to release an internal GLib lock through
g_main_context_release(). That's the first bug.
When xg_select() fails to acquire the internal GLib lock, it simply
does a select() on the remaining file descriptors:
context_acquired = g_main_context_acquire (context);
/* FIXME: If we couldn't acquire the context, we just silently proceed
because this function handles more than just glib file descriptors.
Note that, as implemented, this failure is completely silent: there is
no feedback to the caller. */
This seems like a second, albeit documented, bug to me. I think we're
risking not waking up from the actual select because another
(non-Emacs) thread happened to hold the main context at the time.
- bug#36609: 27.0.50; Possible race-condition in threading implementation, (continued)
- bug#36609: 27.0.50; Possible race-condition in threading implementation, Pip Cet, 2019/07/13
- bug#36609: 27.0.50; Possible race-condition in threading implementation, Eli Zaretskii, 2019/07/13
- bug#36609: 27.0.50; Possible race-condition in threading implementation, Eli Zaretskii, 2019/07/13
- bug#36609: 27.0.50; Possible race-condition in threading implementation, Eli Zaretskii, 2019/07/13
- bug#36609: 27.0.50; Possible race-condition in threading implementation, Pip Cet, 2019/07/13
- bug#36609: 27.0.50; Possible race-condition in threading implementation, Eli Zaretskii, 2019/07/13
- bug#36609: 27.0.50; Possible race-condition in threading implementation, Pip Cet, 2019/07/13
- bug#36609: 27.0.50; Possible race-condition in threading implementation, Andreas Politz, 2019/07/13
bug#36609: 27.0.50; Possible race-condition in threading implementation, Pip Cet, 2019/07/12
- bug#36609: 27.0.50; Possible race-condition in threading implementation, Eli Zaretskii, 2019/07/12
- bug#36609: 27.0.50; Possible race-condition in threading implementation,
Pip Cet <=
- bug#36609: 27.0.50; Possible race-condition in threading implementation, Eli Zaretskii, 2019/07/12
- bug#36609: 27.0.50; Possible race-condition in threading implementation, Pip Cet, 2019/07/12
- bug#36609: 27.0.50; Possible race-condition in threading implementation, Eli Zaretskii, 2019/07/12
- bug#36609: 27.0.50; Possible race-condition in threading implementation, Pip Cet, 2019/07/12
- bug#36609: 27.0.50; Possible race-condition in threading implementation, Eli Zaretskii, 2019/07/13