On Wed, Oct 10, 2018 at 08:17:41PM -0500, Eric Blake wrote: > On 10/10/18 7:05 PM, Peter Xu wrote: > > > > other than the command line that is hanging: > > > > > > /home/eblake/qemu/x86_64-softmmu/qemu-system-x86_64 -S -no-user-config > > > -nodefaults -nographic -machine none,accel=kvm:tcg -qmp > > > unix:/var/lib/libvirt/qemu/capabilities.monitor.sock,server,nowait > > > -pidfile > > > /var/lib/libvirt/qemu/capabilities.pidfile -daemonize > > > > > > And I suspect it is the -daemonize that is causing the hang I'm seeing > > > when > > > run by libvirt. > > > > > > > > It's very possible the daemonize thing, actually Wolfgang Bumiller has > > posted patches to fix this up (it's not the problem of this series, > > but it just exposed this to libvirt by the series since it only > > happens when oob and daemonize are both enabled). The fixes are: > > > > [PATCH v2 0/2] delay monitor iothread creation > > > > Since it cannot be applied cleanly onto this series, I resolved the > > conflicts and pushed a tree here in case you wanna try with these two > > extra patches applied: > > > > https://github.com/xzpeter/qemu/tree/test-oob > > Technically, we should apply the patches in the opposite order (Wolfgang's > first, then yours), so that bisection does not land on a known-bad hang > situation.
Agreed, that patch actually fixes bug of current master (current master could possibly hit the same issue when with x-oob=on and -daemonize), so should be applied earlier when proper. > > > > > Please feel free to test with libvirt again with that. > > > > Thanks for playing with the tree and further investigation! I will > > also mention this in the next version of cover letter (if there is one). > > Confirmed that libvirt no longer hung with Wolfgang's patches added in. Thanks! -- Peter Xu