On 6/12/12, Stefan Hajnoczi <stefanha@xxxxxxxxx> wrote: Further tests done on the following set only >> qemu-kvm-0.12.1.2-2.209.el6_2.4.x86_64 >> on SLES 6, 2.6.32-220.7.1.el.x86_64 (Intel 82801JI ICH10) >> 1. VMM add physical host usb device -> select storage to guest >> 2. VMM remove hardware >> 3. Physically remove the USB storage from the host, thread/core >> assigned to guest goes 100% > > Two clarifications: > > 1. Can you confirm that the 100% CPU utilization only happens in Step > #3? For example, if it happened in Step #2 that would suggest the > guest is entering a loop. Step #3 suggests the host is entering a > loop. Verified Step #3 triggers the issue. > 2. Please run top(1) on the host during high CPU utilization to > confirm which process is causing high CPU utilization. Verified is the VM's process. If unpinned, the utilization floats around the cores, if pinned, the 100% load stays with the physical core. Load on the core stabilizes at around 32% usr 67% sys if the VM is active. Pausing the VM makes it go to around 80+ sys. Other info selinux: no difference between enforcing/permissive Does NOT happen if Step #2 is not done. i.e. simply yanking the USB drive physically gives no problem. The PCI-USB device must be removed from the guest in order for this to trigger. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
