The outcome of the discussion was:
> Yes, downtimes can sometimes be long. I still think it's correct to
> keep the clock going in that case. The guest may give warnings
> because it's seeing something funny with the clock. Something *is*
> funny with the clock, and those warnings are correct. Basically, when
> the downtime is that long we can't really maintain the illusion of a
> continuously running VM. Pretending we can by fudging the clocks is
> not doing our users a service
Does this mean this bug is invalid?
Description of problem: Do off-line migration via "exec:gzip -c > //home/xianwang/STATEFILE.gz", migration status is "completed", then start listening mode with "-incoming "exec: gzip -c -d //home/xianwang/STATEFILE.gz"", guest hit call trace after boot up. Version-Release number of selected component (if applicable): Host: 3.10.0-862.el7.ppc64le qemu-kvm-rhev-2.10.0-21.el7_5.1.ppc64le SLOF-20170724-2.git89f519f.el7.noarch Guest: 3.10.0-847.el7.ppc64le How reproducible: 50% Steps to Reproduce: 1.Boot a guest with qemu cli as "Additional info" 2.Stop vm and save VM state into a compressed file in host (qemu) stop or {"execute":"stop"} (qemu) migrate_set_speed 1G (qemu) migrate -d "exec:gzip -c> /home/xianwang/STATEFILE.gz" after (qemu) info status VM status: paused (postmigrate) 3.Load the file in local host. "-incoming "exec: gzip -c -d /home/xianwang/STATEFILE.gz"" 4.Check network, dd a file and dmesg inside guest Actual results: guest ping external host--successfully dd a file inside guest--successfully dmesg---hit call trace [ 92.520064] Task dump for CPU 0: [ 92.520078] swapper/0 R running task 0 0 0 0x00000000 [ 92.520098] Call Trace: [ 92.520149] [c000000001273b60] [c0000000001efdd8] rcu_idle_exit+0xb8/0x1d0 (unreliable) [ 92.520171] [c000000001273d30] [c00000000167fc98] cpuidle_curr_governor+0x0/0x8 [ 92.520172] Task dump for CPU 1: [ 92.520180] swapper/1 R running task 0 0 1 0x00000800 [ 92.520182] Call Trace: [ 92.520192] [c00000017b82fba0] [c000000001274700] .TOC.+0x0/0x3900 (unreliable) [ 92.520194] [c00000017b82fd70] [c00000000167fc98] cpuidle_curr_governor+0x0/0x8 [ 92.520195] Task dump for CPU 2: [ 92.520203] goa-daemon R running task 0 2344 2343 0x00040080 [ 92.520212] Call Trace: [ 92.520460] [c0000000296bb780] [c0000000296bb810] 0xc0000000296bb810 [ 92.520461] Task dump for CPU 3: [ 92.520468] swapper/3 R running task 0 0 1 0x00000800 [ 92.520470] Call Trace: [ 92.520473] [c00000017b837ba0] [c00000000014e970] post_schedule_idle+0x0/0x30 (unreliable) [ 92.520475] [c00000017b837d70] [c00000000167fc98] cpuidle_curr_governor+0x0/0x8 [ 92.520476] Task dump for CPU 4: [ 92.520477] swapper/4 R running task 0 0 1 0x00000804 [ 92.520479] Call Trace: [ 92.520481] [c00000017b83b5a0] [c00000000001b5e0] show_stack+0x80/0x330 (unreliable) [ 92.520483] [c00000017b83b650] [c00000000014bcf0] dump_cpu_task+0x100/0x1d0 [ 92.520485] [c00000017b83b6c0] [c0000000001f5a34] rcu_check_callbacks+0x724/0xba0 [ 92.520487] [c00000017b83b800] [c0000000000ff68c] update_process_times+0x5c/0xb0 [ 92.520490] [c00000017b83b840] [c0000000001863c4] tick_sched_timer+0x84/0x180 [ 92.520492] [c00000017b83b880] [c00000000012b4d0] __hrtimer_run_queues+0xf0/0x3f0 [ 92.520494] [c00000017b83b920] [c00000000012bdfc] hrtimer_interrupt+0xdc/0x310 [ 92.520495] [c00000017b83b9e0] [c000000000023060] __timer_interrupt+0x90/0x240 [ 92.520497] [c00000017b83ba30] [c0000000000232b0] timer_interrupt+0xa0/0xe0 [ 92.520499] [c00000017b83ba60] [c000000000002a14] decrementer_common+0x114/0x180 [ 92.520516] --- Exception: 901 at plpar_hcall_norets+0x8c/0xdc LR = shared_cede_loop+0xb8/0xd0 [ 92.520520] [c00000017b83bd50] [c000000140000000] 0xc000000140000000 (unreliable) [ 92.520522] [c00000017b83bdc0] [c0000000007e489c] cpuidle_idle_call+0x11c/0x400 [ 92.520523] [c00000017b83be30] [c0000000000a04a8] pseries_lpar_idle+0x18/0x60 [ 92.520525] [c00000017b83be90] [c00000000001bfb8] arch_cpu_idle+0x68/0x160 [ 92.520527] [c00000017b83bec0] [c0000000001723c0] cpu_startup_entry+0x170/0x1e0 [ 92.520530] [c00000017b83bf20] [c000000000050980] start_secondary+0x310/0x340 [ 92.520532] [c00000017b83bf90] [c000000000009a6c] start_secondary_prolog+0x10/0x14 [ 92.520533] Task dump for CPU 5: [ 92.520540] swapper/5 R running task 0 0 1 0x00000800 [ 92.520542] Call Trace: [ 92.520544] [c00000017b83fd70] [c00000000167fc98] cpuidle_curr_governor+0x0/0x8 [ 92.520545] Task dump for CPU 6: [ 92.520553] swapper/6 R running task 0 0 1 0x00000800 [ 92.520555] Call Trace: [ 92.520557] [c00000017b843ba0] [0000000000000008] 0x8 (unreliable) [ 92.520560] [c00000017b843d70] [c00000000167fc98] cpuidle_curr_governor+0x0/0x8 [ 92.520561] Task dump for CPU 7: [ 92.520568] swapper/7 R running task 0 0 1 0x00000800 [ 92.520570] Call Trace: [ 92.520572] [c00000017b847ba0] [c000000001274700] .TOC.+0x0/0x3900 (unreliable) [ 92.520574] [c00000017b847d70] [c00000000167fc98] cpuidle_curr_governor+0x0/0x8 Expected results: guest don't hit call trace Additional info: /usr/libexec/qemu-kvm \ -nodefaults \ -vnc :19 \ -monitor stdio \ -rtc base=utc,clock=host \ -netdev tap,id=tap0,vhost=on \ -boot menu=off,strict=off,order=cdn,once=c \ -m 4096 \ -drive id=drive_image1,if=none,snapshot=off,aio=threads,cache=none,format=qcow2,file=/home/xianwang/rhel75-ppc64le-virtio-scsi.qcow2 \ -vga std \ -machine pseries \ -sandbox off \ -enable-kvm \ -mon chardev=qmp_id_qmpmonitor1,mode=control \ -mon chardev=qmp_id_catch_monitor,mode=control \ -chardev socket,id=qmp_id_qmpmonitor1,path=/var/tmp/monitor-qmpmonitor1,server,nowait \ -chardev socket,id=qmp_id_catch_monitor,path=/var/tmp/monitor-catch_monitor,server,nowait \ -qmp tcp:0:3339,server,nowait \ -device nec-usb-xhci,id=usb1,bus=pci.0,addr=0x3 \ -device virtio-scsi-pci,id=virtio_scsi_pci0,bus=pci.0,addr=0x4 \ -device scsi-hd,id=image1,drive=drive_image1,bus=virtio_scsi_pci0.0,channel=0,scsi-id=0,lun=0,bootindex=0 \ -device virtio-net-pci,mac=9a:8a:8b:8c:8d:8e,id=net0,vectors=4,netdev=tap0,bus=pci.0,addr=0x5 \ -device usb-tablet,id=usb-tablet1,bus=usb1.0,port=1 \ -serial tcp:0:4449,server,nowait \ -smp 4,maxcpus=4,cores=2,threads=1,sockets=2 \ -name "vm" \