systemd hangs while daemon reexec. Reproducible: Always Steps to Reproduce: 1.Make initramfs by dracut without systemd modules; 1.Boot gentoo with systemd init manager; 2.Update sys-apps/systemd package or run systemctl daemon-reexec 1.Make initramfs by dracut or mkosi with systemd as init inside initrd; 1.Boot gentoo with systemd init manager; 2.Switch root hangs Actual Results: May 28 13:28:02 gentoo systemd[1]: Failed to fork off sandboxing environment for executing generators: Protocol error May 28 13:28:02 gentoo systemd[1]: Freezing execution. May 28 13:28:02 gentoo systemd-journald[491]: Failed to send WATCHDOG=1 notification message: Connection refused May 28 13:30:09 gentoo systemd-journald[491]: Failed to send WATCHDOG=1 notification message: Transport endpoint is not connected Any apps who interacts with systemd (resolved, networkd, ..etc) hangs. The problem happens when one init process systemd replace with other init systemd process. Expected Results: No errors. Continue normal operation.
Created attachment 929821 [details] emerge --info
Your steps to reproduce do not make much sense to me: there are four step 1s and two step 2s. Are these two separate failure modes that you have numbered incorrectly? What version of dracut are you using? This issue indicates the problem may be triggered by having a symlink at /tmp: https://github.com/systemd/systemd/issues/29621
> Your steps to reproduce do not make much sense to me: there are four step 1s and two step 2s. Are these two separate failure modes that you have numbered incorrectly? Sorry. This is correct: Steps to Reproduce: case 1: 1.Make initramfs by dracut without systemd modules; 2.Boot gentoo with systemd init manager; 3.Update sys-apps/systemd package or run systemctl daemon-reexec case 2: 1.Make initramfs by dracut or mkosi with systemd as init inside initrd; 2.Boot gentoo with systemd init manager; 3.Switch root hangs > What version of dracut are you using? ``` # qlist -Ive sys-kernel/dracut sys-kernel/dracut-106-r2 ``` I rebuild gentoo-kernel with hardened use flag. The issue still exists. ``` gentoo ~ # dmesg |tail -10 [ 11.231037] netfs: FS-Cache loaded [ 11.671512] RPC: Registered named UNIX socket transport module. [ 11.680124] RPC: Registered udp transport module. [ 11.680129] RPC: Registered tcp transport module. [ 11.680131] RPC: Registered tcp-with-tls transport module. [ 11.680132] RPC: Registered tcp NFSv4.1 backchannel transport module. [ 12.539252] Key type dns_resolver registered [ 13.016849] NFS: Registering the id_resolver key type [ 13.020466] Key type id_resolver registered [ 13.024549] Key type id_legacy registered gentoo ~ # stat /tmp/ File: /tmp/ Size: 200 Blocks: 0 IO Block: 4096 directory Device: 0,40 Inode: 1 Links: 9 Access: (1777/drwxrwxrwt) Uid: ( 0/ root) Gid: ( 0/ root) Access: 2025-05-29 06:37:46.201218476 +0300 Modify: 2025-05-29 06:37:59.079999985 +0300 Change: 2025-05-29 06:37:59.079999985 +0300 Birth: 2025-05-29 06:37:46.201218476 +0300 gentoo ~ # systemctl daemon-reexec gentoo ~ # dmesg |tail -10 [ 13.020466] Key type id_resolver registered [ 13.024549] Key type id_legacy registered [ 394.390989] systemd[1]: systemd 257.5 running in system mode (+PAM +AUDIT -SELINUX -APPARMOR +IMA +IPE +SMACK +SECCOMP +GCRYPT -GNUTLS +OPENSSL +ACL +BLKID +CURL +ELFUTILS +FIDO2 +IDN2 -IDN -IPTC +KMOD +LIBCRYPTSETUP +LIBCRYPTSETUP_PLUGINS +LIBFDISK +PCRE2 -PWQUALITY +P11KIT -QRENCODE +TPM2 +BZIP2 +LZ4 +XZ +ZLIB +ZSTD +BPF_FRAMEWORK +BTF -XKBCOMMON +UTMP -SYSVINIT +LIBARCHIVE) [ 394.399634] systemd[1]: Detected virtualization kvm. [ 394.401080] systemd[1]: Detected architecture x86-64. [ 394.531639] systemd[1]: bpf-restrict-fs: Failed to load BPF object: Invalid argument [ 484.560588] systemd[1]: Failed to fork off sandboxing environment for executing generators: Protocol error [ 484.564853] systemd[1]: Freezing execution. [ 593.468514] systemd-journald[491]: Failed to send WATCHDOG=1 notification message: Connection refused [ 653.469389] systemd-journald[491]: Failed to send WATCHDOG=1 notification message: Transport endpoint is not connected gentoo ~ # systemctl daemon-reload Failed to connect to system scope bus via local transport: Connection refused gentoo ~ # ```
Created attachment 929939 [details] kernel config
> I rebuild gentoo-kernel with hardened use flag. The issue still exists. *without
Ok, I'm afraid I have no idea why it is failing. I would suggest you seek support upstream.
Maybe try booting with the log level set to debug. An easy way to do that is to add this to the kernel command line in your bootloader config. systemd.log-level=debug
Debug logging shows nothing. But I found that freez was because one of systemd-system-generator (netplan). I still have error message: [ 1069.212399] systemd[1]: bpf-restrict-fs: Failed to load BPF object: Invalid argument sys-apps/systemd-257.5::gentoo was built with the following: USE="acl audit boot bpf cryptsetup curl dns-over-tls elfutils fido2 gcrypt importd kernel-install kmod lz4 lzma openssl pam pcre pkcs11 (policykit) seccomp secureboot sysv-utils tpm ukify zstd -apparmor -cgroup-hybrid -gnutls -homed -http -idn -iptables -pwquality -qrcode -resolvconf (-selinux) (-split-usr) -test -vanilla -xkb" PYTHON_SINGLE_TARGET="python3_13 (-python3_11) -python3_12" # zgrep -iE 'bpf|btf' /proc/config.gz CONFIG_BPF=y CONFIG_HAVE_EBPF_JIT=y CONFIG_ARCH_WANT_DEFAULT_BPF_JIT=y # BPF subsystem CONFIG_BPF_SYSCALL=y CONFIG_BPF_JIT=y CONFIG_BPF_JIT_ALWAYS_ON=y CONFIG_BPF_JIT_DEFAULT_ON=y CONFIG_BPF_UNPRIV_DEFAULT_OFF=y CONFIG_BPF_PRELOAD=y # CONFIG_BPF_PRELOAD_UMD is not set CONFIG_BPF_LSM=y # end of BPF subsystem CONFIG_CGROUP_BPF=y CONFIG_IPV6_SEG6_BPF=y CONFIG_NETFILTER_BPF_LINK=y CONFIG_NETFILTER_XT_MATCH_BPF=m CONFIG_NET_CLS_BPF=m CONFIG_NET_ACT_BPF=m CONFIG_BPF_STREAM_PARSER=y CONFIG_LWTUNNEL_BPF=y CONFIG_BPF_LIRC_MODE2=y CONFIG_VIDEO_SONY_BTF_MPX=m # HID-BPF support CONFIG_HID_BPF=y # end of HID-BPF support CONFIG_LSM="landlock,yama,bpf" CONFIG_DEBUG_INFO_BTF=y CONFIG_PAHOLE_HAS_SPLIT_BTF=y CONFIG_DEBUG_INFO_BTF_MODULES=y # CONFIG_MODULE_ALLOW_BTF_MISMATCH is not set CONFIG_PROBE_EVENTS_BTF_ARGS=y CONFIG_BPF_EVENTS=y CONFIG_TEST_BPF=m I don't know open new issue or continue here?
Take it upstream.
(In reply to Alexander Miroshnichenko from comment #8) > Debug logging shows nothing. But I found that freez was because one of > systemd-system-generator (netplan). > > I still have error message: > > [ 1069.212399] systemd[1]: bpf-restrict-fs: Failed to load BPF object: > Invalid argument See https://gcc.gnu.org/PR119731 for this one. It's a kernel bug.
