Description of problem: libvirt use wrong format to scan cpu info in /proc/qemupid/task/cputid/stat Version-Release number of selected component (if applicable): v1.3.2-119-g1e34a8f How reproducible: 100% Steps to Reproduce: 1.start a guest with new build libvirt: # virsh start rhel7.0-rhel Domain rhel7.0-rhel started 2. check guest vcpuinfo # virsh vcpuinfo rhel7.0-rhel VCPU: 0 CPU: 0 State: running CPU Affinity: yyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyy VCPU: 1 CPU: 0 State: running CPU Affinity: yyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyy VCPU: 2 CPU: 0 State: running CPU Affinity: -y------------------------------ 3. check log 2016-03-11 06:59:04.653+0000: 4842: warning : qemuGetProcessInfo:1475 : cannot parse process status data 2016-03-11 06:59:04.662+0000: 4842: warning : qemuGetProcessInfo:1475 : cannot parse process status data 2016-03-11 06:59:04.667+0000: 4842: warning : qemuGetProcessInfo:1475 : cannot parse process status data Actual results: libvirt cannot get cpu time any more. Expected results: parse info success Additional info: i have checked stat: # cat /proc/`pidof qemu-kvm`/task/*/stat 5337 (qemu-kvm) S 1 5335 5335 0 -1 1212162432 12799 0 0 0 84 87 0 0 20 0 6 0 10148852 4755070976 104474 18446744073709551615 140268365217792 140268369549260 140721229100000 140721229098976 140268236880959 0 268444224 4096 16963 18446744071580887989 0 0 17 7 0 0 0 0 0 140268371646608 140268372896098 140268408942592 140721229108868 140721229111181 140721229111181 140721229111266 0 5355 (qemu-kvm) S 1 5335 5335 0 -1 1077944384 18 0 0 0 1 1 0 0 20 0 6 0 10148860 4755070976 104474 18446744073709551615 140268365217792 140268369549260 140721229100000 140268096051672 140268236900681 0 2147221247 4096 16963 18446744071579772004 0 0 -1 5 0 0 0 0 0 140268371646608 140268372896098 140268408942592 140721229108868 140721229111181 140721229111181 140721229111266 0 5374 (CPU 0/KVM) S 1 5335 5335 0 -1 138420416 17876 0 0 0 657 149 0 0 20 0 6 0 10148862 4755070976 104474 18446744073709551615 140268365217792 140268369549260 140721229100000 140263924304184 140268236886615 0 2147220671 4096 16963 18446744072104545539 0 0 -1 13 0 3 0 640 0 140268371646608 140268372896098 140268408942592 140721229108868 140721229111181 140721229111181 140721229111266 0 5376 (CPU 1/KVM) S 1 5335 5335 0 -1 138420416 454 0 0 0 150 10 0 0 20 0 6 0 10148863 4755070976 104474 18446744073709551615 140268365217792 140268369549260 140721229100000 140263915911480 140268236886615 0 2147220671 4096 16963 18446744072104545539 0 0 -1 26 0 5 0 149 0 140268371646608 140268372896098 140268408942592 140721229108868 140721229111181 140721229111181 140721229111266 0 5378 (CPU 2/KVM) S 1 5335 5335 0 -1 138420416 311 0 0 0 119 8 0 0 20 0 6 0 10148863 4755070976 104474 18446744073709551615 140268365217792 140268369549260 140721229100000 140263907518776 140268236886615 0 2147220671 4096 16963 18446744072104545539 0 0 -1 1 0 5 0 120 0 140268371646608 140268372896098 140268408942592 140721229108868 140721229111181 140721229111181 140721229111266 0 5410 (qemu-kvm) S 1 5335 5335 0 -1 1212162240 2040 0 0 0 19 41 0 0 20 0 6 0 10148868 4755070976 104474 18446744073709551615 140268365217792 140268369549260 140721229100000 140263748004112 140268236880765 0 2147220087 4096 16963 18446744071580887989 0 0 -1 5 0 0 0 0 0 140268371646608 140268372896098 140268408942592 140721229108868 140721229111181 140721229111181 140721229111266 0 you can see that vcpu tasks now is : 5374 (CPU 0/KVM) S 1 ... ^ | here is the problem so fscanf in qemuGetProcessInfo cannot parse it then report the warnning
debug-threads=on cause the thread name been changed.
Yeah, that's what we get for using fscanf and we deserve the punishment.
Fixed upstream by v1.3.2-339-g801a5f6: commit 801a5f65fa83f03eb8627875c670652cf8c30e4b Author: Jiri Denemark <jdenemar> AuthorDate: Tue Mar 29 15:35:19 2016 +0200 Commit: Jiri Denemark <jdenemar> CommitDate: Tue Mar 29 16:41:20 2016 +0200 qemu: Fix /proc/**/stat parsing Since commit v1.3.2-119-g1e34a8f which enabled debug-threads in QEMU qemuGetProcessInfo would fail to parse stats for any thread with a space in its name. https://bugzilla.redhat.com/show_bug.cgi?id=1316803 Signed-off-by: Jiri Denemark <jdenemar>