[Qemu-devel] [Bug 1433081] Re: qcow2 causing kvm hardware error 0xffffffff with vfio-pci VGA passthrough

[v2min]

** Description changed:

- Hi,
- 
- Using qcow2 format for an ide-hd device is causing "KVM: entry failed,
- hardware error 0xffffffff". When this error occurs, qemu-monitor shows
- the guest has stopped. The error did not occur immediately, but at the
- point that the boot, running from an attached Ubuntu 14.04.1 iso,
- switched to graphical mode after text-mode startup.
- 
- The root-cause was verified by switching only the ide-hd disk to raw
- format (no OS installed), which allowed the guest to boot normally from
- the iso. The error and fix are reliably repeatable.
- 
- The interesting part is that the ide-hd (with no OS installed) with
- qcow2 format was not actually being used for boot - the boot was from a
- Ubuntu iso, with the intention of installing an ubuntu guest on the
- attached ide-hd device. The guest was using a vfio-pci passthrough GPU
- connected to an external UHD monitor.
- 
- The commands used to create the disk images:
- qemu-img create -f qcow2 
/media/v2min/Data/VMachines-KVM/KVM-NVidia/kvm-nvidia.img 20G
- qemu-img create -f raw 
/media/v2min/Data/VMachines-KVM/KVM-NVidia/kvm-nvidia.img 20G
- 
- The script vm1 was used to launch the guests with "sudo ./vm1", with the
- only difference between launches being the ide-hd format (raw vs qcow2).
- With qcow2 this resulted in the terminal below. The corresponding dmesg
- snippets are attached. There were two dmesg entries each time the error
- occurred.
- 
- The same problem occurred when using the latest packages from the
- ppa:jacob/virtualisation. However, when using jacob's packages, it was
- not verified that raw format resolves the error (I am running this on my
- primary system and purged jacob's ppa when this problem first occured).
- 
- A fix would be helpful as the qcow2 format allows snapshots, while raw
- does not.
- 
- ----------------------------------System 
info-----------------------------------------------------------
- Linux v2min 3.18.9-031809-generic #201503080036 SMP Sun Mar 8 00:37:46 UTC 
2015 x86_64 x86_64 x86_64 GNU/Linux
- 
- /var/log/libvirt/libvirt.d is 0 bytes
- 
- Libvirt versions are these:
- 
- address@hidden:~/QCOW2-Error$ dpkg -l | grep libvirt
- ii  libvirt-bin                         1.2.2-0ubuntu13.1.9        amd64      
  programs for the libvirt library
- rc  libvirt-glib-1.0-0                  0.1.6-1ubuntu2             amd64      
  libvirt glib mainloop integration
- ii  libvirt0                            1.2.2-0ubuntu13.1.9        amd64      
  library for interfacing with different virtualization systems
- ii  python-libvirt                      1.2.2-0ubuntu2             amd64      
  libvirt Python bindings
- 
- 
- address@hidden:~/QCOW2-Error$ dpkg -l | grep qemu
- ii  ipxe-qemu                           1.0.0+git-20131111.c3d1e78-2ubuntu1.1 
              all          PXE boot firmware - ROM images for qemu
- ii  qemu-keymaps                        2.0.0+dfsg-2ubuntu1.10                
              all          QEMU keyboard maps
- ii  qemu-kvm                            2.0.0+dfsg-2ubuntu1.10                
              amd64        QEMU Full virtualization on x86 hardware 
(transitional package)
- ii  qemu-system-common                  2.0.0+dfsg-2ubuntu1.10                
              amd64        QEMU full system emulation binaries (common files)
- ii  qemu-system-x86                     2.0.0+dfsg-2ubuntu1.10                
              amd64        QEMU full system emulation binaries (x86)
- ii  qemu-utils                          2.0.0+dfsg-2ubuntu1.10                
              amd64        QEMU utilities
- 
- Passthrough GPU: Zotac GT 730 2GB.
- Processor: AMD A10-5800K APU
- Primary GPU: Radeon R9-290X
- 
- 
- ------------------------------------------vm1 
script-----------------------------------------------------
- #!/bin/bash
- 
- configfile=/etc/vfio-pci1.cfg
- 
- vfiobind() {
-     dev="$1"
-         vendor=$(cat /sys/bus/pci/devices/$dev/vendor)
-         device=$(cat /sys/bus/pci/devices/$dev/device)
-         if [ -e /sys/bus/pci/devices/$dev/driver ]; then
-                 echo $dev > /sys/bus/pci/devices/$dev/driver/unbind
-         fi
-         echo $vendor $device > /sys/bus/pci/drivers/vfio-pci/new_id
-    
- }
- 
- modprobe vfio-pci
- 
- cat $configfile | while read line;do
-     echo $line | grep ^# >/dev/null 2>&1 && continue
-         vfiobind $line
- done
- 
- sudo qemu-system-x86_64 -enable-kvm -M q35 -m 4096 -cpu host \
- -smp 2,sockets=1,cores=2,threads=1 \
- -bios /usr/share/qemu/bios.bin -vga none \
- -usb -device usb-host,hostbus=5,hostaddr=8 \
- -device 
ioh3420,bus=pcie.0,addr=1c.0,multifunction=on,port=1,chassis=1,id=root.1 \
- -device vfio-pci,host=04:00.0,bus=root.1,addr=00.0,multifunction=on,x-vga=on \
- -device vfio-pci,host=04:00.1,bus=root.1,addr=00.1 \
- -drive 
file=/media/v2min/Data/VMachines-KVM/KVM-NVidia/kvm-nvidia.img,id=disk,format=qcow2
 -device ide-hd,bus=ide.0,drive=disk \
- -drive 
file=/media/v2min/Data/Shr/Software/OSes/ubuntu-14.04.1-desktop-amd64.iso,id=isocd
 -device ide-cd,bus=ide.1,drive=isocd \
- -boot menu=on \
- -boot d
- 
- exit 0
- 
- 
------------------------------------------------------------gnome-terminal-----------------------------
- address@hidden:~$ sudo ./vm1
- [sudo] password for v2min: 
- KVM: entry failed, hardware error 0xffffffff
- RAX=0000000000000005 RBX=0000000000000000 RCX=0000000000000000 
RDX=ffffffff81eaf3e8
- RSI=0000000000000000 RDI=0000000000000000 RBP=ffff880179553930 
RSP=ffff880179553910
- R8 =ffffffff81eaf3e0 R9 =000000000000ffff R10=0000000000000206 
R11=000000000000000f
- R12=ffff880179597b1c R13=0000000000000028 R14=0000000000000000 
R15=ffff880179597800
- RIP=ffffffff8104ed58 RFL=00000046 [---Z-P-] CPL=0 II=0 A20=1 SMM=0 HLT=0
- ES =0000 0000000000000000 ffffffff 00800000
- CS =0010 0000000000000000 ffffffff 00a09b00 DPL=0 CS64 [-RA]
- SS =0018 0000000000000000 ffffffff 00c09300 DPL=0 DS   [-WA]
- DS =0000 0000000000000000 ffffffff 00800000
- FS =0000 00007f51d8a96880 ffffffff 00800000
- GS =0000 ffff88017fd00000 ffffffff 00800000
- LDT=0000 0000000000000000 0000ffff 00000000
- TR =0040 ffff88017fd11900 00002087 00008b00 DPL=0 TSS64-busy
- GDT=     ffff88017fd0a000 0000007f
- IDT=     ffffffffff576000 00000fff
- CR0=8005003b CR2=00007f51d8a99000 CR3=00000001740be000 CR4=000406e0
- DR0=0000000000000000 DR1=0000000000000000 DR2=0000000000000000 
DR3=0000000000000000 
- DR6=00000000ffff0ff0 DR7=0000000000000400
- EFER=0000000000000d01
- Code=00 01 48 c7 c0 6a b0 00 00 31 db 0f b7 0c 01 b8 05 00 00 00 <0f> 01 c1 
0f 1f 44 00 00 5b 41 5c 41 5d 41 5e 5d c3 89 f0 31 c9 f0 0f b0 0d 9b 06 e6 00 40
- address@hidden:~$ sudo ./vm1
- KVM: entry failed, hardware error 0xffffffff
- RAX=0000000000000005 RBX=0000000000000000 RCX=0000000000000000 
RDX=ffffffff81eaf3e8
- RSI=0000000000000000 RDI=0000000000000000 RBP=ffff88017957f9e8 
RSP=ffff88017957f9c8
- R8 =ffffffff81eaf3e0 R9 =0000000000000000 R10=ffff88017b001d00 
R11=0000000000000246
- R12=ffff880179527ac0 R13=000000000000003e R14=0000000000000000 
R15=0000000000000001
- RIP=ffffffff8104ed58 RFL=00000046 [---Z-P-] CPL=0 II=0 A20=1 SMM=0 HLT=0
- ES =0000 0000000000000000 ffffffff 00800000
- CS =0010 0000000000000000 ffffffff 00a09b00 DPL=0 CS64 [-RA]
- SS =0018 0000000000000000 ffffffff 00c09300 DPL=0 DS   [-WA]
- DS =0000 0000000000000000 ffffffff 00800000
- FS =0000 00007f49153a6740 ffffffff 00800000
- GS =0000 ffff88017fd00000 ffffffff 00800000
- LDT=0000 0000000000000000 0000ffff 00000000
- TR =0040 ffff88017fd11900 00002087 00008b00 DPL=0 TSS64-busy
- GDT=     ffff88017fd0a000 0000007f
- IDT=     ffffffffff576000 00000fff
- CR0=8005003b CR2=00007f4914e82170 CR3=0000000001c0e000 CR4=000406e0
- DR0=0000000000000000 DR1=0000000000000000 DR2=0000000000000000 
DR3=0000000000000000 
- DR6=00000000ffff0ff0 DR7=0000000000000400
- EFER=0000000000000d01
- Code=00 01 48 c7 c0 6a b0 00 00 31 db 0f b7 0c 01 b8 05 00 00 00 <0f> 01 c1 
0f 1f 44 00 00 5b 41 5c 41 5d 41 5e 5d c3 89 f0 31 c9 f0 0f b0 0d 9b 06 e6 00 40
+ Please delete this bug report - it's conclusions are incorrect. While
+ the iso boots with raw but not qcow2, attempting to install using the
+ iso causes the same hardware error. Changing smp and cores to 1 allows
+ both qcow2 and raw to move forward with installs.

** Summary changed:

- qcow2 causing kvm hardware error 0xffffffff with vfio-pci VGA passthrough
+ kvm hardware error 0xffffffff with vfio-pci VGA passthrough

** Changed in: qemu
     Assignee: (unassigned) => v2min (straussbd-lp)

** Information type changed from Public to Private

** Changed in: qemu
       Status: New => Invalid

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https://bugs.launchpad.net/bugs/1433081

Title:
  kvm hardware error 0xffffffff with vfio-pci VGA passthrough

Status in QEMU:
  Invalid

Bug description:
  Please delete this bug report - it's conclusions are incorrect. While
  the iso boots with raw but not qcow2, attempting to install using the
  iso causes the same hardware error. Changing smp and cores to 1 allows
  both qcow2 and raw to move forward with installs.

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