[Qemu-devel] [Bug 1175513] Re: Qemu 1.5-git gpu clock control doesn`t work after guest reboot

[Alex Williamson]

Please confirm that you're running the kernel from this branch on the
host system:

git://github.com/awilliam/linux-vfio.git vfio-vga-reset

Both host kernel and qemu changes are required.  Unfortunately the error
code from the ioctl makes it difficult to tell if it isn't available in
the kernel or failed, something I need to correct in getting them
upstream.  These branches only modify the x-vga=on path.  Comment #8
indicates using this hangs the host, but comments #9 & #10 says the bus
reset call didn't work, did you perhaps boot back into the wrong kernel
after the system hang?

>From your lspci, 02:00.0 and 02:00.1 are below the 00:0b.0 root port.
The properties of 00:0b.0 seem to indicate that 02:00.0 and 02:00.1
should be the only iommu group below this root port, so a bus reset
should be available, assuming we're using the correct kernel.  In
addition to verifying the kernel in use, please attach the output of
`find /sys/kernel/iommu_groups/`

-- 
You received this bug notification because you are a member of qemu-
devel-ml, which is subscribed to QEMU.
https://bugs.launchpad.net/bugs/1175513

Title:
  Qemu 1.5-git gpu clock control doesn`t work after guest reboot

Status in QEMU:
  New

Bug description:
  I run qemu from git with such command:

  qemu-system-x86_64 -nodefaults -m 4096 -smp 8,cores=4,threads=2,sockets=1 
-cpu 'kvm64' -device usb-mouse -M q35 -vga qxl -no-hpet -boot once=c,menu=on 
-device vfio-pci,host=02:00.0,x-vga=on \
  -enable-kvm -monitor stdio -chardev 
socket,path=/tmp/qga.sock,server,nowait,id=qga0 -device virtio-serial -device 
virtserialport,chardev=qga0,name=org.qemu.guest_agent.0 -net 
nic,vlan=0,model=e1000 -net tap,ifname=tap0,script=/etc/guest-ifup -usb -device 
intel-hda -device hda-duplex \
  -drive 
file='/home/<user>/qemu/win7',if=none,id=drive-virtio-disk0,cache=writeback,aio=native,format=qed,discard=on
 -device virtio-blk-pci,drive=drive-virtio-disk0,id=virtio-disk \
  -drive 
file='/dev/sr0',if=none,id=drive-ide1-0-0,media=cdrom,snapshot=off,format=raw 
-device ide-drive,bus=ide.1,unit=0,drive=drive-ide1-0-0,id=ide1-0-0 \
  -spice port=5930,disable-ticketing

  Before guest (Windows 7) reboot, videocard works in 3D mode with full
  frequency. But after reboot videocard works in 3D only with powersafe
  frequency. Then I must reboot host for recover gpu clock control.

To manage notifications about this bug go to:
https://bugs.launchpad.net/qemu/+bug/1175513/+subscriptions