Hello, When running "gui-installed-desktop-os-encrypted" test, Shepherd seems to deadlock when restarting "guix-daemon". This can happen at different stages: * In "umount-cow-store" procedure, just before finishing the install. * During "set-http-proxy" tests inside the marionette. This is not always reproducible. In order to gather some information, I created a Shepherd "strace" service that logs what's happening in Shepherd itself (patch attached). It seems that, just after blocking signals, in "fork+exec-command", I guess, Shepherd is taking a lock: --8<---------------cut here---------------start------------->8--- 183553:1 chdir("/") = 0 183554:1 clock_gettime(CLOCK_PROCESS_CPUTIME_ID, {tv_sec=1, tv_nsec=4387222}) = 0 183555:1 rt_sigprocmask(SIG_BLOCK, NULL, [HUP INT TERM CHLD], 8) = 0 183560:1 madvise(0x7f179782d000, 12288, MADV_DONTNEED) = 0 183561:1 clock_gettime(CLOCK_PROCESS_CPUTIME_ID, {tv_sec=1, tv_nsec=13592357}) = 0 183562:1 clone(child_stack=0x7f17981e6fb0, flags=CLONE_VM|CLONE_FS|CLONE_FILES|CLONE_SIGHAND|CLONE_THREAD|CLONE_SYSVSEM|CLONE_SETTLS|CLONE_PARENT_SETTID|CLONE_CHILD_CLEARTID, parent_tid=[271], tls=0x7f17981e7700, child_tidptr=0x7f17981e79d0) = 271 183563:1 stat("/etc/localtime", {st_mode=S_IFREG|0444, st_size=1920, ...}) = 0 183564:1 write(15, "shepherd[1]: changing HTTP/HTTPS"..., 86 183566:1 <... write resumed>) = 86 183575:1 getpgid(169) = 169 183576:1 getpgid(0) = 0 183577:1 kill(-169, SIGTERM 183579:1 <... kill resumed>) = 0 183582:1 stat("/etc/localtime", {st_mode=S_IFREG|0444, st_size=1920, ...}) = 0 183583:1 write(15, "shepherd[1]: Service guix-daemon"..., 51 183585:1 <... write resumed>) = 51 183594:1 getuid() = 0 183595:1 rt_sigprocmask(SIG_BLOCK, [HUP INT TERM CHLD], [HUP INT TERM CHLD], 8) = 0 183596:1 write(6, "\1", 1 183598:1 <... write resumed>) = 1 183605:1 futex(0x7f17981e79d0, FUTEX_WAIT, 271, NULL --8<---------------cut here---------------end--------------->8--- and is then blocking forever. I cannot find any trace of locking in Shepherd, except for "without-automatic-finalization" procedure. Thanks, Mathieu