When the first thread of multimedia/mpv exits after having played a video
with the "gpu" (default) output, the programs receives a SIGSEV when it
tries to execute one of its destructor:
void
_rthread_tls_destructors(pthread_t thread)
{
[...]
for (i = 0; i < PTHREAD_DESTRUCTOR_ITERATIONS; i++) {
for (rs = thread->local_storage; rs; rs = rs->next) {
if (!rs->data)
continue;
if (rkeys[rs->keyid].destructor) {
void (*destructor)(void *) =
rkeys[rs->keyid].destructor;
void *data = rs->data;
rs->data = NULL;
_spinunlock(&rkeyslock);
destructor(data); <-- HERE
_spinlock(&rkeyslock);
}
}
}
[...]
}
This doesn't happen with other outputs and I haven't checked/don't know
which piece of code in the "gpu" output calls pthread_key_create().
Full backtrace below.
$ mpv *.mp4
(+) Video --vid=1 (*) (h264 640x352 30.288fps)
(+) Audio --aid=1 (*) (aac 2ch 48000Hz)
libEGL warning: DRI3: Screen seems not DRI3 capable
AO: [sdl] 48000Hz stereo 2ch s32
VO: [gpu] 640x352 yuv420p
AV: 00:01:38 / 00:01:38 (100%) A-V: 0.000
Exiting... (End of file)
pthread_mutex_destroy on mutex with waiters!
Segmentation fault (core dumped)
mpi@oliva $ egdb /usr/local/bin/mpv *.core
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Reading symbols from /usr/local/bin/mpv...Reading symbols from /usr/local/bin/.d
ebug/mpv.dbg...done.
done.
[New process 566589]
[New process 131102]
[New process 552326]
[New process 162644]
Core was generated by `mpv'.
Program terminated with signal SIGSEGV, Segmentation fault.
#0 0x000009b1220dfa70 in ?? ()
[Current thread is 1 (process 566589)]
(gdb) thr apply all bt
Thread 4 (process 162644):
#0 futex () at /tmp/-:3
#1 0x000009b140ca37b5 in _twait (p=0x9b1417da640, val=1, clockid=0, abs=0x0)
at /usr/src/lib/libc/thread/synch.h:34
#2 _rthread_cond_timedwait (cond=0x9b1417da640, mutexp=0x9b0adcb19c8, abs=0x0)
at /usr/src/lib/libc/thread/rthread_cond.c:106
#3 0x000009aea3812d5c in worker_thread (arg=0x9b0adcb19c0)
at ../mpv-0.32.0/misc/thread_pool.c:80
#4 0x000009b19f5a60c1 in _rthread_start (v=<optimized out>)
at /usr/src/lib/librthread/rthread.c:96
#5 0x000009b140c9d7f8 in __tfork_thread ()
at /usr/src/lib/libc/arch/amd64/sys/tfork_thread.S:77
#6 0x0000000000000000 in ?? ()
Thread 3 (process 552326):
#0 _thread_sys_poll () at /tmp/-:3
#1 0x000009b140c659fe in _libc_poll_cancel (fds=0x9b183f0a630, nfds=2,
timeout=-1) at /usr/src/lib/libc/sys/w_poll.c:27
#2 0x000009aea38b1f11 in terminal_thread (ptr=<optimized out>)
at ../mpv-0.32.0/osdep/terminal-unix.c:395
#3 0x000009b19f5a60c1 in _rthread_start (v=<optimized out>)
at /usr/src/lib/librthread/rthread.c:96
#4 0x000009b140c9d7f8 in __tfork_thread ()
at /usr/src/lib/libc/arch/amd64/sys/tfork_thread.S:77
#5 0x0000000000000000 in ?? ()
Thread 2 (process 131102):
#0 futex () at /tmp/-:3
#1 0x000009b19f5a39a4 in _twait (p=0x9b14dbd5648,
val=<error reading variable: Cannot access memory at address 0x0>,
clockid=<error reading variable: Cannot access memory at address 0x0>,
abs=0x0) at /usr/src/lib/librthread/synch.h:41
#2 _sem_wait (sem=0x9b14dbd5640, can_eintr=0, abstime=0x0,
delayed_cancel=0x9b140cac500 <_initial_thread+200>)
at /usr/src/lib/librthread/rthread_sem.c:76
#3 0x000009b19f5a5bc7 in pthread_join (thread=0x9b14dbd5640, retval=0x0)
at /usr/src/lib/librthread/rthread.c:304
#4 0x000009aea389fecf in vo_destroy (vo=0x9b15860cc40)
at ../mpv-0.32.0/video/out/vo.c:380
#5 0x000009aea3852e5c in uninit_video_out (mpctx=0x9b126f8b840)
at ../mpv-0.32.0/player/video.c:130
#6 0x000009aea384a037 in mp_destroy (mpctx=0x9b126f8b840)
at ../mpv-0.32.0/player/main.c:167
#7 0x000009aea384ace4 in mpv_main (argc=<optimized out>, argv=<optimized out>)
at ../mpv-0.32.0/player/main.c:490
#8 0x000009aea37b99f1 in ___start ()
#9 0x0000000000000000 in ?? ()
Thread 1 (process 566589):
#0 0x000009b1220dfa70 in ?? ()
#1 0x000009b140c85075 in _rthread_tls_destructors (thread=0x9b14dbd5640)
at /usr/src/lib/libc/thread/rthread_tls.c:182
#2 0x000009b140c3db93 in _libc_pthread_exit (retval=<optimized out>)
at /usr/src/lib/libc/thread/rthread.c:150
#3 0x000009b19f5a60c9 in _rthread_start (v=<optimized out>)
at /usr/src/lib/librthread/rthread.c:97
#4 0x000009b140c9d7f8 in __tfork_thread ()
at /usr/src/lib/libc/arch/amd64/sys/tfork_thread.S:77
#5 0x0000000000000000 in ?? ()
