[Bug 203477] New: [AMD][KVM] Windows L1 guest becomes extremely slow and unusable after enabling Hyper-V

[Bug 203477] New: [AMD][KVM] Windows L1 guest becomes extremely slow and unusable after enabling Hyper-V

[bugzilla-daemon]

https://bugzilla.kernel.org/show_bug.cgi?id=203477

            Bug ID: 203477
           Summary: [AMD][KVM] Windows L1 guest becomes extremely slow and
                    unusable after enabling Hyper-V
           Product: Virtualization
           Version: unspecified
    Kernel Version: Debian 4.19.28-2~bpo9+1
          Hardware: All
                OS: Linux
              Tree: Mainline
            Status: NEW
          Severity: normal
          Priority: P1
         Component: kvm
          Assignee: virtualization_kvm@kernel-bugs.osdl.org
          Reporter: hjc@hjc.im
        Regression: No

Created attachment 282583
  --> https://bugzilla.kernel.org/attachment.cgi?id=282583&action=edit
libvirt XML

I'm not sure if it is a supported scenario to run Hyper-V inside KVM, however
this worked for me on Intel platform, and I only have this issue on AMD Ryzen.

After enabling Hyper-V feature in Windows guest, I could successfully boot into
Windows L1 guest desktop, however after that the L1 guest system consumes all
available CPU cores, freezes and becomes unusable. 

Hardware platform:  
CPU: AMD Ryzen Threadripper 2950X
Board: ASUS Prime X399-A (SVM, IOMMU related settings enabled in BIOS)


Linux boot command line: BOOT_IMAGE=/boot/vmlinuz-4.19.0-0.bpo.4-amd64
root=UUID=<guid> ro quiet apparmor=0 amd_iommu=pt nopti noibrs noibpb
nospectre_v2 nospec_store_bypass_disable pcie_aspm=off apparmor=0

KVM module parameters:
options kvm ignore_msrs=1
options kvm report_ignored_msrs=0
options kvm allow_unsafe_assigned_interrupts=1
options vfio_iommu_type1 allow_unsafe_interrupts=1


QEMU: QEMU emulator version 4.0.0 built with ./configure
--target-list=x86_64-softmmu --audio-drv-list=pa,alsa,sdl,oss --enable-attr
--enable-bluez --enable-brlapi --enable-virtfs --enable-cap-ng --enable-curl
--enable-fdt --enable-gnutls --disable-gtk --disable-vte --enable-libiscsi
--enable-libnfs --enable-curses --enable-numa --enable-rbd --enable-glusterfs
--enable-vnc-sasl --enable-sdl --enable-seccomp --enable-spice --enable-libusb
--enable-usb-redir --enable-libssh2 --enable-vde --enable-xfsctl --enable-vnc
--enable-vnc-jpeg --enable-vnc-png --enable-kvm --enable-vhost-net
--enable-opengl --enable-virglrenderer --enable-avx2 --enable-tpm
--enable-vhost-kernel --enable-virtfs

libvirt XML is attached

L1 Guest OS: Windows Server 2016, 2019 and Windows 10
L2 Guest OS: (Not ever had a chance to start one)


`perf kvm stat live` shows unusual numbers of vmrun and msr, comparing to
normal VMs:
             VM-EXIT    Samples  Samples%     Time%    Min Time    Max Time    
    Avg time 

               vmrun      71298    47.13%     2.61%      1.07us  46197.83us    
19.09us ( +-   9.11% )
                 msr      71217    47.08%     1.24%      0.61us  31213.68us    
 9.04us ( +-  10.45% )
                 hlt       3465     2.29%    95.58%      0.70us  78318.83us 
14370.28us ( +-   0.93% )
                 npf       2053     1.36%     0.38%      0.64us  15532.20us    
96.25us ( +-  26.48% )
             invlpga       1514     1.00%     0.00%      0.28us     60.25us    
 1.06us ( +-  10.58% )
           interrupt        740     0.49%     0.04%      0.22us  15289.36us    
25.67us ( +-  80.62% )
               vintr        328     0.22%     0.12%      0.37us  31341.32us   
194.65us ( +-  59.60% )
                stgi        134     0.09%     0.00%      0.32us     49.18us    
 1.34us ( +-  31.81% )
                iret        133     0.09%     0.00%      0.28us      1.52us    
 0.58us ( +-   3.36% )
                  io        119     0.08%     0.00%      2.37us     51.02us    
14.38us ( +-   4.98% )
           hypercall        104     0.07%     0.03%      0.77us  15522.73us   
152.12us ( +-  98.10% )
                 nmi         96     0.06%     0.00%      0.67us     40.84us    
 2.89us ( +-  20.49% )
           write_cr8         66     0.04%     0.00%      0.72us      3.09us    
 1.77us ( +-   3.19% )

There are also a few number of errors in kmsg after L1 guest boots:
[755580.533587] svm_set_msr: 2 callbacks suppressed
[755580.533588] SVM: kvm [14227]: vcpu0, guest rIP: 0xfffff986014dca0c
unimplemented wrmsr: 0xc0010115 data 0x0
[755581.191889] SVM: kvm [14227]: vcpu1, guest rIP: 0xfffff986014dca0c
unimplemented wrmsr: 0xc0010115 data 0x0
[755581.323561] SVM: kvm [14227]: vcpu2, guest rIP: 0xfffff986014dca0c
unimplemented wrmsr: 0xc0010115 data 0x0
[755581.482291] SVM: kvm [14227]: vcpu3, guest rIP: 0xfffff986014dca0c
unimplemented wrmsr: 0xc0010115 data 0x0
[755581.642842] SVM: kvm [14227]: vcpu4, guest rIP: 0xfffff986014dca0c
unimplemented wrmsr: 0xc0010115 data 0x0
[755581.803020] SVM: kvm [14227]: vcpu5, guest rIP: 0xfffff986014dca0c
unimplemented wrmsr: 0xc0010115 data 0x0
[755581.963498] SVM: kvm [14227]: vcpu6, guest rIP: 0xfffff986014dca0c
unimplemented wrmsr: 0xc0010115 data 0x0
[755582.123565] SVM: kvm [14227]: vcpu7, guest rIP: 0xfffff986014dca0c
unimplemented wrmsr: 0xc0010115 data 0x0
[755616.107080] SVM: kvm [14227]: vcpu0, guest rIP: 0xfffffb735a8dca0c
unimplemented wrmsr: 0xc0010115 data 0x0
[755616.778183] SVM: kvm [14227]: vcpu1, guest rIP: 0xfffffb735a8dca0c
unimplemented wrmsr: 0xc0010115 data 0x0
[755616.910078] SVM: kvm [14227]: vcpu2, guest rIP: 0xfffffb735a8dca0c
unimplemented wrmsr: 0xc0010115 data 0x0
[755617.047056] SVM: kvm [14227]: vcpu3, guest rIP: 0xfffffb735a8dca0c
unimplemented wrmsr: 0xc0010115 data 0x0
[755617.180127] SVM: kvm [14227]: vcpu4, guest rIP: 0xfffffb735a8dca0c
unimplemented wrmsr: 0xc0010115 data 0x0
[755617.327040] SVM: kvm [14227]: vcpu5, guest rIP: 0xfffffb735a8dca0c
unimplemented wrmsr: 0xc0010115 data 0x0
[755617.487152] SVM: kvm [14227]: vcpu6, guest rIP: 0xfffffb735a8dca0c
unimplemented wrmsr: 0xc0010115 data 0x0
[755617.626337] SVM: kvm [14227]: vcpu7, guest rIP: 0xfffffb735a8dca0c
unimplemented wrmsr: 0xc0010115 data 0x0

-- 
You are receiving this mail because:
You are watching the assignee of the bug.

[Bug 203477] [AMD][KVM] Windows L1 guest becomes extremely slow and unusable after enabling Hyper-V

[bugzilla-daemon]

https://bugzilla.kernel.org/show_bug.cgi?id=203477

lol123lol125@gmail.com changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |lol123lol125@gmail.com

--- Comment #1 from lol123lol125@gmail.com ---
I am having a similar probably the same issue with proxmox 6/windows server
2019. i am able to boot an ubuntu image as l2 guest. But Either the l1 system
is unresponsive or it crashes with a bluesceen before reaching the gui.
Bluescreens seem to be all watchdog related but vary. (DPC Watchdog
Violation,clock watchdog timeout).



Hardware platform:  
CPU: AMD Ryzen Threadripper 2950X
Board: ASRock X399 Taichi X399-A (SVM, IOMMU related settings enabled in BIOS)


root@pve-master:~# grep -H '' /sys/module/kvm_amd/parameters/*
/sys/module/kvm_amd/parameters/avic:0
/sys/module/kvm_amd/parameters/nested:1
/sys/module/kvm_amd/parameters/npt:1
/sys/module/kvm_amd/parameters/pause_filter_count:3000
/sys/module/kvm_amd/parameters/pause_filter_count_grow:2
/sys/module/kvm_amd/parameters/pause_filter_count_max:65535
/sys/module/kvm_amd/parameters/pause_filter_count_shrink:0
/sys/module/kvm_amd/parameters/pause_filter_thresh:128
/sys/module/kvm_amd/parameters/sev:0
/sys/module/kvm_amd/parameters/vgif:1
/sys/module/kvm_amd/parameters/vls:1

root@pve-master:~# grep -H '' /sys/module/kvm/parameters/*
/sys/module/kvm/parameters/enable_vmware_backdoor:N
/sys/module/kvm/parameters/force_emulation_prefix:N
/sys/module/kvm/parameters/halt_poll_ns:200000
/sys/module/kvm/parameters/halt_poll_ns_grow:0
/sys/module/kvm/parametQers/halt_poll_ns_shrink:0
/sys/module/kvm/parameters/ignore_msrs:Y
/sys/module/kvm/parameters/kvmclock_periodic_sync:Y
/sys/module/kvm/parameters/lapic_timer_advance_ns:4294967295
/sys/module/kvm/parameters/min_timer_period_us:200
/sys/module/kvm/parameters/report_ignored_msrs:N
/sys/module/kvm/parameters/tsc_tolerance_ppm:250
/sys/module/kvm/parameters/vector_hashing:Y


/usr/bin/kvm -id 114 -name server2019 -chardev
socket,id=qmp,path=/var/run/qemu-server/114.qmp,server,nowait -mon
chardev=qmp,mode=control -chardev
socket,id=qmp-event,path=/var/run/qmeventd.sock,reconnect=5 -mon
chardev=qmp-event,mode=control -pidfile /var/run/qemu-server/114.pid -daemonize
-smbios type=1,uuid=8167be1e-8f3d-4667-8535-62a035ebd087 -smp
6,sockets=1,cores=6,maxcpus=6 -nodefaults -boot
menu=on,strict=on,reboot-timeout=1000,splash=/usr/share/qemu-server/bootsplash.jpg
-vnc unix:/var/run/qemu-server/114.vnc,password -no-hpet -cpu
EPYC,+kvm_pv_unhalt,+kvm_pv_eoi,hv_spinlocks=0x1fff,hv_vapic,hv_time,hv_reset,hv_vpindex,hv_runtime,hv_relaxed,hv_synic,hv_stimer,hv_tlbflush,hv_ipi,enforce,vendor=AuthenticAMD
-m 8192 -device vmgenid,guid=53ded4c7-f067-4ae6-8ab0-6a571ccbc1ba -readconfig
/usr/share/qemu-server/pve-q35-4.0.cfg -device
qxl-vga,id=vga,bus=pcie.0,addr=0x1 -spice
tls-port=61000,addr=127.0.0.1,tls-ciphers=HIGH,seamless-migration=on -device
virtio-serial,id=spice,bus=pci.0,addr=0x9 -chardev
spicevmc,id=vdagent,name=vdagent -device
virtserialport,chardev=vdagent,name=com.redhat.spice.0 -device
virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x3 -iscsi
initiator-name=iqn.1993-08.org.debian:01:6ff4f776953c -drive
file=/pool_t1/t1_dir//template/iso/virtio-win-0.1.141.iso,if=none,id=drive-ide0,media=cdrom,aio=threads
-device ide-cd,bus=ide.0,unit=0,drive=drive-ide0,id=ide0,bootindex=200 -drive
file=/pool_t1/t1_dir//template/iso/winserver19_17763.1.180914-1434.rs5_release_SERVER_EVAL_x64fre_de-de.iso,if=none,id=drive-ide2,media=cdrom,aio=threads
-device ide-cd,bus=ide.1,unit=0,drive=drive-ide2,id=ide2,bootindex=201 -drive
file=/dev/zvol/pool_t1/vmdata/vm-114-disk-0,if=none,id=drive-virtio0,format=raw,cache=none,aio=native,detect-zeroes=on
-device
virtio-blk-pci,drive=drive-virtio0,id=virtio0,bus=pci.0,addr=0xa,bootindex=100
-netdev
type=tap,id=net0,ifname=tap114i0,script=/var/lib/qemu-server/pve-bridge,downscript=/var/lib/qemu-server/pve-bridgedown,vhost=on
-device
virtio-net-pci,mac=16:72:12:9F:33:FA,netdev=net0,bus=pci.0,addr=0x12,id=net0,bootindex=300
-rtc driftfix=slew,base=localtime -machine type=q35 -global
kvm-pit.lost_tick_policy=discard -cpu host,+svm

-- 
You are receiving this mail because:
You are watching the assignee of the bug.

[Bug 203477] [AMD][KVM] Windows L1 guest becomes extremely slow and unusable after enabling Hyper-V

[bugzilla-daemon]

https://bugzilla.kernel.org/show_bug.cgi?id=203477

wUFr (jiribelsky@hotmail.com) changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |jiribelsky@hotmail.com

--- Comment #2 from wUFr (jiribelsky@hotmail.com) ---
I have same errors pop in "dmesg", but only when my second VM (Ubuntu 18.04) is
running. Windows 10 VM does not seem to be causing these (at least not for me).
Kernel 5.1.16-050116-generic (Elementary OS 5), QEMU emulator version
2.11.1(Debian 1:2.11+dfsg-1ubuntu7.15). Can post configs later if needed

-- 
You are receiving this mail because:
You are watching the assignee of the bug.

[Bug 203477] [AMD][KVM] Windows L1 guest becomes extremely slow and unusable after enabling Hyper-V

[bugzilla-daemon]

https://bugzilla.kernel.org/show_bug.cgi?id=203477

--- Comment #3 from Eduardo Frazão (edufrazao@gmail.com) ---
I have the exact same errors, but here my Windows 10 Pro L1 freezes few seconds
start. I'm trying to use Windows SandBox.

Ryzen 3700x // Gigabyte X570 Aorus Elite
Kernel 5.3.0.

I have AMD SVM enabled in BIOS and IOMMU disabled.



beast ~ # grep -H '' /sys/module/kvm_amd/parameters/*
/sys/module/kvm_amd/parameters/avic:0
/sys/module/kvm_amd/parameters/dump_invalid_vmcb:N
/sys/module/kvm_amd/parameters/nested:1
/sys/module/kvm_amd/parameters/npt:1
/sys/module/kvm_amd/parameters/nrips:1
/sys/module/kvm_amd/parameters/pause_filter_count:3000
/sys/module/kvm_amd/parameters/pause_filter_count_grow:2
/sys/module/kvm_amd/parameters/pause_filter_count_max:65535
/sys/module/kvm_amd/parameters/pause_filter_count_shrink:0
/sys/module/kvm_amd/parameters/pause_filter_thresh:128
/sys/module/kvm_amd/parameters/sev:0
/sys/module/kvm_amd/parameters/vgif:1
/sys/module/kvm_amd/parameters/vls:1

beast ~ # grep -H '' /sys/module/kvm/parameters/*
/sys/module/kvm/parameters/enable_vmware_backdoor:N
/sys/module/kvm/parameters/force_emulation_prefix:N
/sys/module/kvm/parameters/halt_poll_ns:200000
/sys/module/kvm/parameters/halt_poll_ns_grow:2
/sys/module/kvm/parameters/halt_poll_ns_grow_start:10000
/sys/module/kvm/parameters/halt_poll_ns_shrink:0
/sys/module/kvm/parameters/ignore_msrs:Y
/sys/module/kvm/parameters/kvmclock_periodic_sync:Y
/sys/module/kvm/parameters/lapic_timer_advance_ns:-1
/sys/module/kvm/parameters/min_timer_period_us:200
/sys/module/kvm/parameters/pi_inject_timer:0
/sys/module/kvm/parameters/report_ignored_msrs:Y
/sys/module/kvm/parameters/tsc_tolerance_ppm:250
/sys/module/kvm/parameters/vector_hashing:Y


QEMU Command line:
usr/bin/qemu-system-x86_64 -name guest=Win10Devel,debug-threads=on -S -object
secret,id=masterKey0,format=raw,file=/var/lib/libvirt/qemu/domain-1-Win10Devel/master-key.aes
-machine pc-q35-4.0.1,accel=kvm,usb=off,dump-guest-core=off -cpu
EPYC-IBPB,svm=on,hv_time,hv_relaxed,hv_vapic,hv_spinlocks=0x1fff -m 6072
-overcommit mem-lock=off -smp 4,sockets=1,cores=2,threads=2 -uuid
466412cf-36da-4297-ba3e-6f7e7b0b0b5d -no-user-config -nodefaults -chardev
socket,id=charmonitor,fd=22,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 -global
ICH9-LPC.disable_s3=1 -global ICH9-LPC.disable_s4=1 -boot strict=on -device
pcie-root-port,port=0x10,chassis=1,id=pci.1,bus=pcie.0,multifunction=on,addr=0x2
-device pcie-root-port,port=0x11,chassis=2,id=pci.2,bus=pcie.0,addr=0x2.0x1
-device pcie-root-port,port=0x12,chassis=3,id=pci.3,bus=pcie.0,addr=0x2.0x2
-device pcie-root-port,port=0x13,chassis=4,id=pci.4,bus=pcie.0,addr=0x2.0x3
-device pcie-root-port,port=0x14,chassis=5,id=pci.5,bus=pcie.0,addr=0x2.0x4
-device pcie-root-port,port=0x15,chassis=6,id=pci.6,bus=pcie.0,addr=0x2.0x5
-device qemu-xhci,p2=15,p3=15,id=usb,bus=pci.2,addr=0x0 -device
virtio-serial-pci,id=virtio-serial0,bus=pci.3,addr=0x0 -drive
file=/mnt/storage/Eduardo/VM/KVM/win10_desenvolvimento.qcow2,format=qcow2,if=none,id=drive-virtio-disk0,cache=none,aio=native
-device
virtio-blk-pci,scsi=off,bus=pci.4,addr=0x0,drive=drive-virtio-disk0,id=virtio-disk0,bootindex=2,write-cache=on
-drive if=none,id=drive-sata0-0-1,readonly=on -device
ide-cd,bus=ide.1,drive=drive-sata0-0-1,id=sata0-0-1,bootindex=1 -drive
if=none,id=drive-fdc0-0-0 -device isa-fdc,driveA=drive-fdc0-0-0 -netdev
tap,fd=24,id=hostnet0,vhost=on,vhostfd=25 -device
virtio-net-pci,netdev=hostnet0,id=net0,mac=52:54:00:00:2f:ca,bus=pci.1,addr=0x0
-chardev pty,id=charserial0 -device isa-serial,chardev=charserial0,id=serial0
-chardev spicevmc,id=charchannel0,name=vdagent -device
virtserialport,bus=virtio-serial0.0,nr=1,chardev=charchannel0,id=channel0,name=com.redhat.spice.0
-chardev socket,id=charchannel1,fd=26,server,nowait -device
virtserialport,bus=virtio-serial0.0,nr=2,chardev=charchannel1,id=channel1,name=org.qemu.guest_agent.0
-chardev spiceport,id=charchannel2,name=org.spice-space.webdav.0 -device
virtserialport,bus=virtio-serial0.0,nr=3,chardev=charchannel2,id=channel2,name=org.spice-space.webdav.0
-device usb-tablet,id=input0,bus=usb.0,port=1 -spice
port=5900,addr=127.0.0.1,disable-ticketing,image-compression=off,seamless-migration=on
-device
qxl-vga,id=video0,ram_size=134217728,vram_size=134217728,vram64_size_mb=0,vgamem_mb=64,max_outputs=1,bus=pcie.0,addr=0x1
-device virtio-balloon-pci,id=balloon0,bus=pci.5,addr=0x0 -sandbox
on,obsolete=deny,elevateprivileges=deny,spawn=deny,resourcecontrol=deny -msg
timestamp=on

-- 
You are receiving this mail because:
You are watching the assignee of the bug.

[Bug 203477] [AMD][KVM] Windows L1 guest becomes extremely slow and unusable after enabling Hyper-V

[bugzilla-daemon]

https://bugzilla.kernel.org/show_bug.cgi?id=203477

--- Comment #4 from Timo Sandmann (lists@cety.de) ---
I have the same problem on a Ryzen 3950x (Asus PRIME X570-PRO) with kernel
5.6.19 (Fedora 32).

-- 
You are receiving this mail because:
You are watching the assignee of the bug.

[Bug 203477] [AMD][KVM] Windows L1 guest becomes extremely slow and unusable after enabling Hyper-V

[bugzilla-daemon]

https://bugzilla.kernel.org/show_bug.cgi?id=203477

Yonggang Luo (luoyonggang@gmail.com) changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |luoyonggang@gmail.com

--- Comment #5 from Yonggang Luo (luoyonggang@gmail.com) ---
I have the same problem on a Ryzen 3950x, are this a problem in kvm or in
windows guest or in qemu?

-- 
You are receiving this mail because:
You are watching the assignee of the bug.

[Bug 203477] [AMD][KVM] Windows L1 guest becomes extremely slow and unusable after enabling Hyper-V

[bugzilla-daemon]

https://bugzilla.kernel.org/show_bug.cgi?id=203477

--- Comment #6 from Yonggang Luo (luoyonggang@gmail.com) ---
The command line I am using
```
/usr/bin/kvm -id 101 -name Win10-Video -chardev
socket,id=qmp,path=/var/run/qemu-server/101.qmp,server,nowait -mon
chardev=qmp,mode=control -chardev
socket,id=qmp-event,path=/var/run/qmeventd.sock,reconnect=5 -mon
chardev=qmp-event,mode=control -pidfile /var/run/qemu-server/101.pid -daemonize
-smbios type=1,uuid=0e1a8f04-2fcd-4e7b-a615-b5f60c17c244 -smp
16,sockets=1,cores=16,maxcpus=16 -nodefaults -boot
menu=on,strict=on,reboot-timeout=1000,splash=/usr/share/qemu-server/bootsplash.jpg
-vnc unix:/var/run/qemu-server/101.vnc,password -no-hpet -cpu
kvm64,enforce,hv_ipi,hv_relaxed,hv_reset,hv_runtime,hv_spinlocks=0x1fff,hv_stimer,hv_synic,hv_time,hv_vapic,hv_vpindex,+kvm_pv_eoi,+kvm_pv_unhalt,+lahf_lm,+sep
-m 16384 -readconfig /usr/share/qemu-server/pve-q35-4.0.cfg -device
vmgenid,guid=4d51db1b-14b4-48ee-a10e-87e12165dd90 -device
nec-usb-xhci,id=xhci,bus=pci.1,addr=0x1b -device
usb-tablet,id=tablet,bus=ehci.0,port=1 -device
usb-host,bus=xhci.0,hostbus=4,hostport=2,id=usb0 -device
qxl-vga,id=vga,bus=pcie.0,addr=0x1 -device
virtio-serial,id=spice,bus=pci.0,addr=0x9 -chardev
spicevmc,id=vdagent,name=vdagent -device
virtserialport,chardev=vdagent,name=com.redhat.spice.0 -spice
tls-port=61000,addr=127.0.0.1,tls-ciphers=HIGH,seamless-migration=on -device
virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x3 -iscsi
initiator-name=iqn.1993-08.org.debian:01:fbd3a8f979d -drive
file=/var/lib/vz/template/iso/virtio-win-0.1.189.iso,if=none,id=drive-ide0,media=cdrom,aio=threads
-device ide-cd,bus=ide.0,unit=0,drive=drive-ide0,id=ide0,bootindex=200 -drive
file=/var/lib/vz/template/iso/cn_windows_10_business_editions_version_2004_updated_sep_2020_x64_dvd_7134ba4b.iso,if=none,id=drive-ide2,media=cdrom,aio=threads
-device ide-cd,bus=ide.1,unit=0,drive=drive-ide2,id=ide2,bootindex=201 -drive
file=/dev/pve/vm-101-disk-0,if=none,id=drive-virtio0,format=raw,cache=none,aio=native,detect-zeroes=on
-device
virtio-blk-pci,drive=drive-virtio0,id=virtio0,bus=pci.0,addr=0xa,bootindex=100
-netdev
type=tap,id=net0,ifname=tap101i0,script=/var/lib/qemu-server/pve-bridge,downscript=/var/lib/qemu-server/pve-bridgedown,vhost=on
-device
virtio-net-pci,mac=AE:79:28:76:97:65,netdev=net0,bus=pci.0,addr=0x12,id=net0,bootindex=300
-rtc driftfix=slew,base=localtime -machine type=q35+pve0 -global
kvm-pit.lost_tick_policy=discard -cpu
host,enforce,hv_ipi,hv_relaxed,hv_reset,hv_runtime,hv_spinlocks=0x1fff,hv_stimer,hv_synic,hv_time,hv_vapic,hv_vpindex,+kvm_pv_eoi,+kvm_pv_unhalt,+lahf_lm,+sep,+svm,-hypervisor
```

-- 
You are receiving this mail because:
You are watching the assignee of the bug.

[Bug 203477] [AMD][KVM] Windows L1 guest becomes extremely slow and unusable after enabling Hyper-V

[bugzilla-daemon]

https://bugzilla.kernel.org/show_bug.cgi?id=203477

vkuznets@redhat.com changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |vkuznets@redhat.com

--- Comment #7 from vkuznets@redhat.com ---
(In reply to Yonggang Luo from comment #6)
>-cpu
> host,enforce,hv_ipi,hv_relaxed,hv_reset,hv_runtime,hv_spinlocks=0x1fff,
> hv_stimer,hv_synic,hv_time,hv_vapic,hv_vpindex,+kvm_pv_eoi,+kvm_pv_unhalt,
> +lahf_lm,+sep,+svm,-hypervisor
> ```

Try adding 'hv_stimer_direct' to the list, Hyper-V can't use synthetic timers
otherwise. Also, why do you need '-hypervisor' flag? Could you try without it?

Also, please try with the latest upstream kernel (5.9). 5.3 has a lot of known
nested SVM related bugs.

-- 
You are receiving this mail because:
You are watching the assignee of the bug.

[Bug 203477] [AMD][KVM] Windows L1 guest becomes extremely slow and unusable after enabling Hyper-V

[bugzilla-daemon]

https://bugzilla.kernel.org/show_bug.cgi?id=203477

--- Comment #8 from Timo Sandmann (lists@cety.de) ---
An upgrade to kernel 5.8.13 solved the issue for me.

-- 
You are receiving this mail because:
You are watching the assignee of the bug.

[Bug 203477] [AMD][KVM] Windows L1 guest becomes extremely slow and unusable after enabling Hyper-V

[bugzilla-daemon]

https://bugzilla.kernel.org/show_bug.cgi?id=203477

--- Comment #9 from Yonggang Luo (luoyonggang@gmail.com) ---
(In reply to Timo Sandmann from comment #8)
> An upgrade to kernel 5.8.13 solved the issue for me.

What's youd qemu command line parameters?

-- 
You may reply to this email to add a comment.

You are receiving this mail because:
You are watching the assignee of the bug.

[Bug 203477] [AMD][KVM] Windows L1 guest becomes extremely slow and unusable after enabling Hyper-V

[bugzilla-daemon]

https://bugzilla.kernel.org/show_bug.cgi?id=203477

hjc@hjc.im changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
         Resolution|---                         |OBSOLETE

--- Comment #10 from hjc@hjc.im ---
Confirmed that it is no longer an issue on 6.1.0 kernel.

-- 
You may reply to this email to add a comment.

You are receiving this mail because:
You are watching the assignee of the bug.