| Summary: | systemctl start xxx hung, strace -p pid show: recvmsg(4, 0x7fffd1450970, MSG_DONTWAIT|MSG_NOSIGNAL|MSG_CMSG_CLOEXEC) = -1 EAGAIN (Resource temporarily unavailable) | ||
|---|---|---|---|
| Product: | Red Hat Enterprise Linux 7 | Reporter: | yzh <1062635196> |
| Component: | systemd | Assignee: | systemd-maint |
| Status: | CLOSED INSUFFICIENT_DATA | QA Contact: | qe-baseos-daemons |
| Severity: | unspecified | Docs Contact: | |
| Priority: | unspecified | ||
| Version: | 7.2 | CC: | 1062635196, bblaskov, jsynacek, paul.clements, systemd-maint-list |
| Target Milestone: | rc | ||
| Target Release: | --- | ||
| Hardware: | Unspecified | ||
| OS: | Unspecified | ||
| Whiteboard: | |||
| Fixed In Version: | Doc Type: | If docs needed, set a value | |
| Doc Text: | Story Points: | --- | |
| Clone Of: | Environment: | ||
| Last Closed: | 2017-01-25 12:04:20 UTC | Type: | Bug |
| Regression: | --- | Mount Type: | --- |
| Documentation: | --- | CRM: | |
| Verified Versions: | Category: | --- | |
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |
| Cloudforms Team: | --- | Target Upstream Version: | |
It is better to use --no-block when you are calling systemctl from script. Especially when tehere is a chance that that script will be called from systemd service. (In reply to Lukáš Nykrýn from comment #2) > It is better to use --no-block when you are calling systemctl from script. > Especially when tehere is a chance that that script will be called from > systemd service. I don't understander the means what's you said. What is the reason for this service to hung? What can I do to solve this problem，or to avoid the problem? I think this a bug of systemd, because of i didn't do anything, except call daemon(), And I think other service also have the problem when systemctl start xxx . (In reply to Lukáš Nykrýn from comment #2) > It is better to use --no-block when you are calling systemctl from script. > Especially when tehere is a chance that that script will be called from > systemd service. I don't understander the means what's you said. What is the reason for this service to hung? What can I do to solve this problem，or to avoid the problem? I think this a bug of systemd, because of i didn't do anything, except call daemon(), And I think other service also have the problem when systemctl start xxx . Hi, There is a lot of service hung when systemctl start xxx today. The services also didn't do anything, except call daemon(). I find the process of the service socket with pid = 1(/usr/lib/systemd/systemd --switched-root),so the log of strace is systemctl Internal socket communication. You give advice to use --no-block, I think it is no use, because of my service is xxxx.service , no xxxx.socket. I need your help, and now this problem has affected the normal work. I hope you can give me some advice to avoid the problem. Had better be able to find the cause of the problem, I also look at the code here to find way to solve the problem. Thank you very much. There's nothing we can do with so little information. If you still have the problem, please provide a reproducer. I have the same problem. Here is the end of the strace of:
systemctl start lifekeeper
recvmsg(3, {msg_name(0)=NULL, msg_iov(1)=[{"l\4\1\1B\0\0\0\6\0\0\0q\0\0\0\1\1o\0\31\0\0\0", 24}], msg_controllen=32, {cmsg_len=28, cmsg_level=SOL_SOCKET, cmsg_type=SCM_CREDENTIALS{pid=1, uid=0, gid=0}}, msg_flags=MSG_CMSG_CLOEXEC}, MSG_DONTWAIT|MSG_NOSIGNAL|MSG_CMSG_CLOEXEC) = 24
recvmsg(3, {msg_name(0)=NULL, msg_iov(1)=[{"/org/freedesktop/systemd1\0\0\0\0\0\0\0"..., 178}], msg_controllen=32, {cmsg_len=28, cmsg_level=SOL_SOCKET, cmsg_type=SCM_CREDENTIALS{pid=1, uid=0, gid=0}}, msg_flags=MSG_CMSG_CLOEXEC}, MSG_DONTWAIT|MSG_NOSIGNAL|MSG_CMSG_CLOEXEC) = 178
recvmsg(3, {msg_name(0)=NULL, msg_iov(1)=[{"l\4\1\1M\0\0\0\7\0\0\0z\0\0\0\1\1o\0\31\0\0\0", 24}], msg_controllen=32, {cmsg_len=28, cmsg_level=SOL_SOCKET, cmsg_type=SCM_CREDENTIALS{pid=1, uid=0, gid=0}}, msg_flags=MSG_CMSG_CLOEXEC}, MSG_DONTWAIT|MSG_NOSIGNAL|MSG_CMSG_CLOEXEC) = 24
recvmsg(3, {msg_name(0)=NULL, msg_iov(1)=[{"/org/freedesktop/systemd1\0\0\0\0\0\0\0"..., 197}], msg_controllen=32, {cmsg_len=28, cmsg_level=SOL_SOCKET, cmsg_type=SCM_CREDENTIALS{pid=1, uid=0, gid=0}}, msg_flags=MSG_CMSG_CLOEXEC}, MSG_DONTWAIT|MSG_NOSIGNAL|MSG_CMSG_CLOEXEC) = 197
recvmsg(3, 0x7ffd8ea88e20, MSG_DONTWAIT|MSG_NOSIGNAL|MSG_CMSG_CLOEXEC) = -1 EAGAIN (Resource temporarily unavailable)
ppoll([{fd=3, events=POLLIN}], 1, NULL, NULL, 8) = 1 ([{fd=3, revents=POLLIN}])
recvmsg(3, {msg_name(0)=NULL, msg_iov(1)=[{"l\4\1\1H\0\0\0\10\0\0\0\226\0\0\0\1\1o\0004\0\0\0", 24}], msg_controllen=32, {cmsg_len=28, cmsg_level=SOL_SOCKET, cmsg_type=SCM_CREDENTIALS{pid=1, uid=0, gid=0}}, msg_flags=MSG_CMSG_CLOEXEC}, MSG_DONTWAIT|MSG_NOSIGNAL|MSG_CMSG_CLOEXEC) = 24
recvmsg(3, {msg_name(0)=NULL, msg_iov(1)=[{"/org/freedesktop/systemd1/unit/s"..., 216}], msg_controllen=32, {cmsg_len=28, cmsg_level=SOL_SOCKET, cmsg_type=SCM_CREDENTIALS{pid=1, uid=0, gid=0}}, msg_flags=MSG_CMSG_CLOEXEC}, MSG_DONTWAIT|MSG_NOSIGNAL|MSG_CMSG_CLOEXEC) = 216
recvmsg(3, {msg_name(0)=NULL, msg_iov(1)=[{"l\4\1\1\304\2\0\0\t\0\0\0\226\0\0\0\1\1o\0004\0\0\0", 24}], msg_controllen=32, {cmsg_len=28, cmsg_level=SOL_SOCKET, cmsg_type=SCM_CREDENTIALS{pid=1, uid=0, gid=0}}, msg_flags=MSG_CMSG_CLOEXEC}, MSG_DONTWAIT|MSG_NOSIGNAL|MSG_CMSG_CLOEXEC) = 24
recvmsg(3, {msg_name(0)=NULL, msg_iov(1)=[{"/org/freedesktop/systemd1/unit/s"..., 852}], msg_controllen=32, {cmsg_len=28, cmsg_level=SOL_SOCKET, cmsg_type=SCM_CREDENTIALS{pid=1, uid=0, gid=0}}, msg_flags=MSG_CMSG_CLOEXEC}, MSG_DONTWAIT|MSG_NOSIGNAL|MSG_CMSG_CLOEXEC) = 852
recvmsg(3, 0x7ffd8ea88e20, MSG_DONTWAIT|MSG_NOSIGNAL|MSG_CMSG_CLOEXEC) = -1 EAGAIN (Resource temporarily unavailable)
ppoll([{fd=3, events=POLLIN}], 1, NULL, NULL, 8) = 1 ([{fd=3, revents=POLLIN}])
recvmsg(3, {msg_name(0)=NULL, msg_iov(1)=[{"l\4\1\1Q\0\0\0\n\0\0\0x\0\0\0\1\1o\0\31\0\0\0", 24}], msg_controllen=32, {cmsg_len=28, cmsg_level=SOL_SOCKET, cmsg_type=SCM_CREDENTIALS{pid=1, uid=0, gid=0}}, msg_flags=MSG_CMSG_CLOEXEC}, MSG_DONTWAIT|MSG_NOSIGNAL|MSG_CMSG_CLOEXEC) = 24
recvmsg(3, {msg_name(0)=NULL, msg_iov(1)=[{"/org/freedesktop/systemd1\0\0\0\0\0\0\0"..., 193}], msg_controllen=32, {cmsg_len=28, cmsg_level=SOL_SOCKET, cmsg_type=SCM_CREDENTIALS{pid=1, uid=0, gid=0}}, msg_flags=MSG_CMSG_CLOEXEC}, MSG_DONTWAIT|MSG_NOSIGNAL|MSG_CMSG_CLOEXEC) = 193
recvmsg(3, 0x7ffd8ea88e20, MSG_DONTWAIT|MSG_NOSIGNAL|MSG_CMSG_CLOEXEC) = -1 EAGAIN (Resource temporarily unavailable)
ppoll([{fd=3, events=POLLIN}], 1, NULL, NULL, 8) = 1 ([{fd=3, revents=POLLIN}])
recvmsg(3, {msg_name(0)=NULL, msg_iov(1)=[{"l\4\1\1Q\0\0\0\v\0\0\0p\0\0\0\1\1o\0\31\0\0\0", 24}], msg_controllen=32, {cmsg_len=28, cmsg_level=SOL_SOCKET, cmsg_type=SCM_CREDENTIALS{pid=1, uid=0, gid=0}}, msg_flags=MSG_CMSG_CLOEXEC}, MSG_DONTWAIT|MSG_NOSIGNAL|MSG_CMSG_CLOEXEC) = 24
recvmsg(3, {msg_name(0)=NULL, msg_iov(1)=[{"/org/freedesktop/systemd1\0\0\0\0\0\0\0"..., 185}], msg_controllen=32, {cmsg_len=28, cmsg_level=SOL_SOCKET, cmsg_type=SCM_CREDENTIALS{pid=1, uid=0, gid=0}}, msg_flags=MSG_CMSG_CLOEXEC}, MSG_DONTWAIT|MSG_NOSIGNAL|MSG_CMSG_CLOEXEC) = 185
recvmsg(3, {msg_name(0)=NULL, msg_iov(1)=[{"l\4\1\1Q\0\0\0\f\0\0\0x\0\0\0\1\1o\0\31\0\0\0", 24}], msg_controllen=32, {cmsg_len=28, cmsg_level=SOL_SOCKET, cmsg_type=SCM_CREDENTIALS{pid=1, uid=0, gid=0}}, msg_flags=MSG_CMSG_CLOEXEC}, MSG_DONTWAIT|MSG_NOSIGNAL|MSG_CMSG_CLOEXEC) = 24
recvmsg(3, {msg_name(0)=NULL, msg_iov(1)=[{"/org/freedesktop/systemd1\0\0\0\0\0\0\0"..., 193}], msg_controllen=32, {cmsg_len=28, cmsg_level=SOL_SOCKET, cmsg_type=SCM_CREDENTIALS{pid=1, uid=0, gid=0}}, msg_flags=MSG_CMSG_CLOEXEC}, MSG_DONTWAIT|MSG_NOSIGNAL|MSG_CMSG_CLOEXEC) = 193
recvmsg(3, 0x7ffd8ea88e20, MSG_DONTWAIT|MSG_NOSIGNAL|MSG_CMSG_CLOEXEC) = -1 EAGAIN (Resource temporarily unavailable)
ppoll([{fd=3, events=POLLIN}], 1, NULL, NULL, 8) = 1 ([{fd=3, revents=POLLIN}])
recvmsg(3, {msg_name(0)=NULL, msg_iov(1)=[{"l\4\1\1Q\0\0\0\r\0\0\0p\0\0\0\1\1o\0\31\0\0\0", 24}], msg_controllen=32, {cmsg_len=28, cmsg_level=SOL_SOCKET, cmsg_type=SCM_CREDENTIALS{pid=1, uid=0, gid=0}}, msg_flags=MSG_CMSG_CLOEXEC}, MSG_DONTWAIT|MSG_NOSIGNAL|MSG_CMSG_CLOEXEC) = 24
recvmsg(3, {msg_name(0)=NULL, msg_iov(1)=[{"/org/freedesktop/systemd1\0\0\0\0\0\0\0"..., 185}], msg_controllen=32, {cmsg_len=28, cmsg_level=SOL_SOCKET, cmsg_type=SCM_CREDENTIALS{pid=1, uid=0, gid=0}}, msg_flags=MSG_CMSG_CLOEXEC}, MSG_DONTWAIT|MSG_NOSIGNAL|MSG_CMSG_CLOEXEC) = 185
recvmsg(3, {msg_name(0)=NULL, msg_iov(1)=[{"l\4\1\1Q\0\0\0\16\0\0\0x\0\0\0\1\1o\0\31\0\0\0", 24}], msg_controllen=32, {cmsg_len=28, cmsg_level=SOL_SOCKET, cmsg_type=SCM_CREDENTIALS{pid=1, uid=0, gid=0}}, msg_flags=MSG_CMSG_CLOEXEC}, MSG_DONTWAIT|MSG_NOSIGNAL|MSG_CMSG_CLOEXEC) = 24
recvmsg(3, {msg_name(0)=NULL, msg_iov(1)=[{"/org/freedesktop/systemd1\0\0\0\0\0\0\0"..., 193}], msg_controllen=32, {cmsg_len=28, cmsg_level=SOL_SOCKET, cmsg_type=SCM_CREDENTIALS{pid=1, uid=0, gid=0}}, msg_flags=MSG_CMSG_CLOEXEC}, MSG_DONTWAIT|MSG_NOSIGNAL|MSG_CMSG_CLOEXEC) = 193
recvmsg(3, 0x7ffd8ea88e20, MSG_DONTWAIT|MSG_NOSIGNAL|MSG_CMSG_CLOEXEC) = -1 EAGAIN (Resource temporarily unavailable)
ppoll([{fd=3, events=POLLIN}], 1, NULL, NULL, 8
systemctl just hangs and doesn't ever progress.
I can add --no-block, and it doesn't hang, but it just exits 0 and doesn't start the service:
systemctl start --no-block --no-ask-password lifekeeper; echo $?
0
system information: rpm -q systemd systemd-219-67.el7_7.2.x86_64 uname -a Linux baymax 3.10.0-327.el7.x86_64 #1 SMP Thu Nov 19 22:10:57 UTC 2015 x86_64 x86_64 x86_64 GNU/Linux |
Description of problem: 1、I have two service hung when systemctl start xxx(but this rarely happens ): a、 /bin/bash -xe ./post_deploy.d/sso_proxy.sh \_ /bin/bash -xe ./resources/sso_proxy/install.sh \_ systemctl start hssoproxy b、 /bin/hotplugusb \_sh -c systemctl start authorize_server \_systemctl start authorize_server 2、Two service didn't do anything else, except calling daemon(), When systemctl start the service; 3、strace -p pid -s 1024 : ppoll([{fd=4, events=POLLIN}], 1, NULL, NULL, 8) = 1 ([{fd=4, revents=POLLIN}]) recvmsg(4, {msg_name(0)=NULL, msg_iov(1)=[{"l\4\1\1I\0\0\0\233\245\1\0p\0\0\0\1\1o\0\31\0\0\0", 24}], msg_controllen=32, {cmsg_len=28, cmsg_level=SOL_SOCKET, cmsg_type=SCM_CREDENTIALS{pid=1, uid=0, gid=0}}, msg_flags=MSG_CMSG_CLOEXEC}, MSG_DONTWAIT|MSG_NOSIGNAL|MSG_CMSG_CLOEXEC) = 24 .......................... recvmsg(4, 0x7fffd1450970, MSG_DONTWAIT|MSG_NOSIGNAL|MSG_CMSG_CLOEXEC) = -1 EAGAIN (Resource temporarily unavailable) ppoll([{fd=4, events=POLLIN}], 1, NULL, NULL, 8) = 1 ([{fd=4, revents=POLLIN}]) ........... recvmsg(4, 0x7fffd1450970, MSG_DONTWAIT|MSG_NOSIGNAL|MSG_CMSG_CLOEXEC) = -1 EAGAIN (Resource temporarily unavailable) Two services are like this, as the above has been circulating. Version-Release number of selected component (if applicable): How reproducible: This situation rarely occurs, the phenomenon is difficult to reproduce Steps to Reproduce: 1. 2. 3. Actual results: Expected results: Additional info: