- deadlock proven first: chatty child (200 KB stdout, stderr held open)
hung the old sequential drain 5.0 s into the alarm, code -1, stdout
truncated at 8192; the leg demands completion under 4 s
- rework: nonblocking pipe read ends + pidfd_open behind one epoll fd the
fiber parks on (the _dl retry mould); both pipes drain on readiness, so
the deadlock is gone structurally — leg passes in 15 ms
- wo_child slot table in wo_vm (32/shard) carries cross-park state; caps
refuse by name (kill + WO_T_IO), deadline armed via dl_active/dl_at,
defaults 30 s / 1 MiB / 64 KiB
- WO_B_PROC_RUN_DL = 96 shares the case (per-call deadline_ms/out_cap/
err_cap; compiler row lands in a later task)
- fib_reap kills a reaped fiber's child; wo_vm_destroy sweeps the table
- raw syscalls for pidfd_open/pidfd_send_signal: glibc 2.35 build floor
has no wrappers
- all 19 suites green under ASan+UBSan
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
shoney.arickathil
258222c3a1