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cmd/ate-env-guest: run under a minimal PID 1 init to reap orphaned children - #106
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Tomer Glottmann (tomergee) wants to merge 1 commit into
Open
Tomer Glottmann (tomergee) wants to merge 1 commit into
Tomer Glottmann (tomergee) wants to merge 1 commit into
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…ildren When ate-env-guest starts as PID 1 inside an actor container or microVM, re-execute the guest server as a supervised child process and reap all reparented descendants in PID 1 via wait4(-1, WNOHANG) without racing os/exec's cmd.Wait() in ProcessService or sidecar supervisors. Fixes #105
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Fixes #105.
Problem
Inside an actor container or microVM,
ate-env-gueststarts as PID 1 (/proc/1/comm=ate-env-guest). PID 1 inherits every orphaned descendant whose parent exits first, and is the only process that can reap them.ate-env-guestwaits on its own direct children (guest/process/tracker.goandcmd/ate-env-guest/sidecar.go), but had no orphan reaper, causing reparented grandchildren to accumulate as zombies (Z) for the lifetime of the guest.Solution
runIfPID1()incmd/ate-env-guest/init_linux.go(invoked at the start ofmain()), following the same minimal-init pattern asagent-substrate/substrate#2626.os.Getpid() == 1, PID 1 re-executesate-env-guestas a supervised child process, forwards termination/user signals (SIGTERM,SIGINT,SIGHUP,SIGQUIT,SIGUSR1,SIGUSR2) to it, and loopssyscall.Wait4(-1, &status, syscall.WNOHANG, nil)onSIGCHLDto reap all reparented orphans without racingos/exec'scmd.Wait()in the guest server.TestSuperviseReturnsExitCode,TestSuperviseReturnsSignalExitCode,TestSuperviseReapsOrphans,TestSuperviseForwardsSignals) usingPR_SET_CHILD_SUBREAPER.