Description of problem: Running qemu-kvm (and thus libvirt/kvm) just hangs with no activity on some hardware. Right now the only affected hardware that we have noticed this on some Intel Xeon based processors (These are the Fedora build hosts and thus they can no longer run ImageFactory to build images). Here is reproducer and a list of hardware and success/failure: Steps to try to reproduce issue: 1. cd /root/ 2. wget http://download.cirros-cloud.net/0.3.4/cirros-0.3.4-x86_64-disk.img 3. /usr/bin/qemu-kvm -m 1024 -name f15 -drive file=/root/cirros-0.3.4-x86_64-disk.img,if=virtio -nographic IT IS A SUCCESS IF YOU SEE SERIAL CONSOLE OUTPUT IT IS A FAILURE IF YOU SEE NO OUTPUT AND NOTHING HAPPENS NOTE - to get out of qemu: ctrl-a c then type 'quit' ***RESULTS*** [dl160 server FAILURE] model name : Intel(R) Xeon(R) CPU L5520 @ 2.27GHz [root@cob-dl160 ~]# rpm -q kernel qemu-kvm kernel-4.2.3-300.fc23.x86_64 kernel-4.2.5-300.fc23.x86_64 qemu-kvm-2.4.0.1-1.fc23.x86_64 # Tried with newer and older kernel [IBM Product Name: BladeCenter HS22 -[7870AC1]- FAILURE] model name : Intel(R) Xeon(R) CPU E5540 @ 2.53GHz kernel-4.2.5-300.fc23.x86_64 qemu-kvm-2.4.1-1.fc23.x86_64 [ibm x3250 m4 SUCCESS] Intel(R) Xeon(R) CPU E3-1220 V2 @ 3.10GHz] kernel-4.2.5-300.fc23.x86_64 qemu-kvm-2.4.1-1.fc23.x86_64 [Lenovo laptop Success] model name : Intel(R) Core(TM) i7-3520M CPU @ 2.90GHz [root@hattop ~]# rpm -q kernel qemu-kvm kernel-4.2.3-300.fc23.x86_64 qemu-kvm-2.4.0.1-1.fc23.x86_64 [Dell server success] model name : Six-Core AMD Opteron(tm) Processor 2419 EE [root@cob-dell9 ~]# rpm -q kernel qemu-kvm kernel-4.2.3-300.fc23.x86_64 qemu-kvm-2.4.0.1-1.fc23.x86_64 [Lenovo T500 Success] model name : Intel(R) Core(TM)2 Duo CPU T9600 @ 2.80GHz [root@cob-T500 ~]# rpm -q kernel qemu-kvm kernel-4.2.3-300.fc23.x86_64 qemu-kvm-2.4.0.1-1.fc23.x86_64 [Lenovo T450s Success] model name :Intel(R) Core(TM) i7-5600U CPU @ 2.60GHz [prkumar@localhost ~]$ rpm -q kernel qemu-kvm kernel-4.2.5-300.fc23.x86_64 qemu-kvm-2.4.1-1.fc23.x86_64
Paolo, is this related to bug 1278688?
As denoted in https://bugzilla.redhat.com/show_bug.cgi?id=1278688 this is fixed in newer versions of the kernel (>4.3). Using kernel kernel-4.4.0-0.rc1.git0.1.fc24.x86_64 it worked: dnf install fedora-repos-rawhide dnf update kernel --enablerepo=rawhide reboot
*********** MASS BUG UPDATE ************** We apologize for the inconvenience. There is a large number of bugs to go through and several of them have gone stale. Due to this, we are doing a mass bug update across all of the Fedora 23 kernel bugs. Fedora 23 has now been rebased to 4.7.4-100.fc23. Please test this kernel update (or newer) and let us know if you issue has been resolved or if it is still present with the newer kernel. If you have moved on to Fedora 24 or 25, and are still experiencing this issue, please change the version to Fedora 24 or 25. If you experience different issues, please open a new bug report for those.
As denoted in comment #2 this is fixed.