On Sat, Nov 16, 2019 at 01:58:55PM -0700, Alex Williamson wrote: > On Thu, 10 Oct 2019 09:30:08 -0300 > Marcelo Tosatti <mtosa...@redhat.com> wrote: > > > commit 369b41359af46bded5799c9ef8be2b641d92e043 broke timer interrupt > > reinjection when there is no period change by the guest. > > > > In that case, old_period is 0, which ends up zeroing irq_coalesced > > (counter of reinjected interrupts). > > > > The consequence is Windows 7 is unable to synchronize time via NTP. > > Easily reproducible by playing a fullscreen video with cirrus and VNC. > > > > Fix by not updating s->irq_coalesced when old_period is 0. > > > > V2: reorganize code (Paolo Bonzini) > > > > Signed-off-by: Marcelo Tosatti <mtosa...@redhat.com> > > This causes a regression for me, my win10 VM with assigned GPU > experiences hangs and slowness with this. Found via bisect, reverting > restores normal behavior. libvirt uses this commandline: > > /usr/local/bin/qemu-system-x86_64 \ > -name guest=Steam-GeForce,debug-threads=on \ > -S \ > -object > secret,id=masterKey0,format=raw,file=/var/lib/libvirt/qemu/domain-1-Steam-GeForce/master-key.aes > \ > -machine pc-i440fx-4.1,accel=kvm,usb=off,vmport=off,dump-guest-core=off \ > -cpu > host,hv-time,hv-relaxed,hv-vapic,hv-spinlocks=0x1fff,hv-vendor-id=KeenlyKVM,kvm=off > \ > -drive > file=/usr/share/edk2/ovmf/OVMF_CODE.fd,if=pflash,format=raw,unit=0,readonly=on > \ > -drive > file=/var/lib/libvirt/qemu/nvram/Steam_VARS.fd,if=pflash,format=raw,unit=1 \ > -m 4096 \ > -mem-prealloc \ > -mem-path /dev/hugepages/libvirt/qemu/1-Steam-GeForce \ > -overcommit mem-lock=off \ > -smp 4,sockets=1,cores=2,threads=2 \ > -uuid 2b417d4b-f25b-4522-a5be-e105f032f99c \ > -display none \ > -no-user-config \ > -nodefaults \ > -chardev socket,id=charmonitor,fd=38,server,nowait \ > -mon chardev=charmonitor,id=monitor,mode=control \ > -rtc base=localtime,driftfix=slew \ > -global kvm-pit.lost_tick_policy=delay \ > -no-hpet \ > -no-shutdown \ > -boot menu=on,strict=on \ > -device nec-usb-xhci,id=usb,bus=pci.0,addr=0x8 \ > -device virtio-scsi-pci,id=scsi0,num_queues=4,bus=pci.0,addr=0x5 \ > -drive > file=/mnt/ssd/Steam.qcow2,format=qcow2,if=none,id=drive-scsi0-0-0-0,cache=none > \ > -device > scsi-hd,bus=scsi0.0,channel=0,scsi-id=0,lun=0,device_id=drive-scsi0-0-0-0,drive=drive-scsi0-0-0-0,id=scsi0-0-0-0,bootindex=2,write-cache=on > \ > -netdev tap,fd=40,id=hostnet0,vhost=on,vhostfd=41 \ > -device > virtio-net-pci,netdev=hostnet0,id=net0,mac=52:54:00:60:ef:ac,bus=pci.0,addr=0x3 > \ > -device vfio-pci,host=0000:01:00.0,id=hostdev0,bus=pci.0,addr=0x4,rombar=1 \ > -device vfio-pci,host=0000:01:00.1,id=hostdev1,bus=pci.0,addr=0x6,rombar=0 \ > -S \ > -debugcon file:/tmp/Steam-ovmf-debug.log \ > -global isa-debugcon.iobase=0x402 \ > -set device.hostdev0.x-pci-vendor-id=0x10de \ > -trace events=/var/lib/libvirt/images/Steam-GeForce.events \ > -sandbox > on,obsolete=deny,elevateprivileges=deny,spawn=deny,resourcecontrol=deny \ > -msg timestamp=on
Alex, -rtc base=localtime,driftfix=none should fix it. Can you confirm?
