On 11/27/2017 at 05:55 PM Michal Kubecek wrote: > On Mon, Nov 27, 2017 at 05:46:14PM +0100, Andreas Hartmann wrote: >> >> Using virtio not just breaks the network completely as described above, >> it even leaves a never stoppable or restartable qemu process (even kill >> -9 doesn't work). It's absolutely necessary to *force* a reboot to exit >> or restart the VM. >> >> I switched back to linux 4.13 as 4.14 virtualization is quite unusable. >> >> I'm not the only one affected: >> https://bugzilla.kernel.org/show_bug.cgi?id=197861 > > What does stack trace of that process look like (/proc/$pid/stack)? Is > it similar to the stack trace from kernel.org bugzilla?
Unfortunately, I didn't look at /proc/$pid/stack at this moment (I had two hanging VMs). I didn't get any log entry neither on the host nor in the VM. I tried to strace one - but strace didn't show anything, two. As I could see at the moment now, according to the logfiles of the VMs, they have been shutdown completely - but qemu can't be killed: Nov 26 20:43:08 proxy systemd: Stopping Remount Root and Kernel File Systems... Nov 26 20:43:08 proxy systemd: Stopping Monitoring of LVM2 mirrors, snapshots etc. using dmeventd or progress polling... Nov 26 20:43:08 proxy systemd: Stopped Create Static Device Nodes in /dev. Nov 26 20:43:08 proxy systemd: Stopping Create Static Device Nodes in /dev... Nov 26 20:43:08 proxy systemd: Reached target Shutdown. Nov 26 20:43:08 proxy systemd: Starting Shutdown. Nov 26 20:43:08 proxy systemd: Reached target Final Step. Nov 26 20:43:08 proxy systemd: Starting Final Step. Nov 26 20:43:08 proxy systemd: Starting Power-Off... Nov 26 20:43:08 proxy systemd: Shutting down. Nov 26 20:43:08 proxy lvm: 3 logical volume(s) in volume group "centos" unmonitored Nov 26 20:43:08 proxy systemd-shutdown[1]: Sending SIGTERM to remaining processes... Nov 26 20:43:08 proxy lvmetad[500]: Failed to accept connection errno 11. Nov 26 20:43:08 proxy journal: Journal stopped Anyway, I reproduced the situation at the moment to get a stack while qemu hangs forever. It looks like this: [<ffffffffc0d0e3c5>] vhost_net_ubuf_put_and_wait+0x35/0x60 [vhost_net] [<ffffffffc0d0f264>] vhost_net_ioctl+0x304/0x870 [vhost_net] [<ffffffff9b25460f>] do_vfs_ioctl+0x8f/0x5c0 [<ffffffff9b254bb4>] SyS_ioctl+0x74/0x80 [<ffffffff9b00365b>] do_syscall_64+0x5b/0x100 [<ffffffff9b78e7ab>] entry_SYSCALL64_slow_path+0x25/0x25 [<ffffffffffffffff>] 0xffffffffffffffff Regards, Andreas
