Packer: Not possible to *add* custom qemu '-device'

[alexz-kh]

Not possible to pass custom qemu '-device' args

packer version
Packer v1.3.1

• Host platform

uname -a ; dpkg -l |grep qemu
Linux s1 -87-generic #110-Ubuntu SMP Tue Jul 18 12:55:35 UTC 2017 x86_64 x86_64 x86_64 GNU/Linux
ii  ipxe-qemu                          1.0.0+git-20150424.a25a16d-1ubuntu1.2      all          PXE boot firmware - ROM images for qemu
ii  qemu-block-extra:amd64             1:2.5+dfsg-5ubuntu10.16                    amd64        extra block backend modules for qemu-system and qemu-utils
ii  qemu-kvm                           1:2.5+dfsg-5ubuntu10.16                    amd64        QEMU Full virtualization
ii  qemu-system-common                 1:2.5+dfsg-5ubuntu10.16                    amd64        QEMU full system emulation binaries (common files)
ii  qemu-system-x86                    1:2.5+dfsg-5ubuntu10.16                    amd64        QEMU full system emulation binaries (x86)
ii  qemu-utils                         1:2.5+dfsg-5ubuntu10.16                    amd64        QEMU utilities

template.json:

...
    {                                                                           
      "type": "qemu",                                                           
      "qemuargs": [                                                             
        [                                                                       
          "-m",                                                                 
          "8096M"                                                               
        ],                                                                      
        [                                                                       
          "-fda",                                                               
          "config-drive/cloudata.iso"                                           
        ],                                                                      
        [                                                                       
          "-smp",                                                               
          "4"                                                                   
        ],                                                                      
        ["-object","rng-random,id=objrng0,filename=/dev/urandom"],              
        ["-device", "virtio-rng-pci,rng=objrng0,id=rng0,bus=pci.0,addr=0x10" ]  
      ],  
...

From debug log:

# W\o device section
Executing /usr/bin/qemu-system-x86_64: []string{"-name", "mcp-offline-mirror-2018-10-24-13-22-19-201810241122", "-netdev", "user,id=user.0,hostfwd=tcp::7021-:22", "-boot", "c", "-vnc", "0.0.0.0:56", "-machine", "type=pc,accel=kvm", "-device", "virtio-net,netdev=user.0", "-drive", "file=images/mcp-offline-mirror-2018-10-24-13-22-19-qemu-201810241122/mcp-offline-mirror-2018-10-24-13-22-19-201810241122,if=virtio,cache=writeback,discard=ignore,format=qcow2", "-m", "8096M", "-fda", "config-drive/cloudata.iso", "-smp", "4"}

# With device section
Executing /usr/bin/qemu-system-x86_64: []string{"-name", "mcp-offline-mirror-2018-10-24-13-23-42-201810241123", "-fda", "config-drive/cloudata.iso", "-object", "rng-random,id=objrng0,filename=/dev/urandom", "-machine", "type=pc,accel=kvm", "-netdev", "user,id=user.0,hostfwd=tcp::7003-:22", "-boot", "c", "-vnc", "0.0.0.0:56", "-m", "8096M", "-smp", "4", "-device", "virtio-rng-pci,rng=objrng0,id=rng0,bus=pci.0,addr=0x10", "-drive", "file=images/mcp-offline-mirror-2018-10-24-13-23-42-qemu-201810241123/mcp-offline-mirror-2018-10-24-13-23-42-201810241123,if=virtio,cache=writeback,discard=ignore,format=qcow2"}

looks like packer exactly overwrite default one:
"-device", "virtio-net,netdev=user.0"
with passed
"-device", "virtio-rng-pci,rng=objrng0,id=rng0,bus=pci.0,addr=0x10"

[SwampDragons]

Hi! I believe this should be closed by a recent PR, #6807 -- this will be going out with the v. 1.3.2 release that should be happening this week or next, but if you want to test it out, here's a linux build of the current master branch, which contains this patch:

packer.zip

[SwampDragons]

I'll keep this issue open until you can confirm whether your issue is solved.

[alexz-kh]

I just quickly w\a it with manual passing both 'devices'.
Would check those with new release, and post result.
Thanks for quick response!

[alexz-kh]

Ah...just saw attachments,
yup, in attached version of packer - issue fixed.
Thanks!

[trodemaster]

I'm still having issues with this on packer linux 1.3.2. I'm using
"disk_interface": "virtio-scsi",

A full functioning qemu string looks like this for me.
Executing /usr/local/bin/qemu-system-x86_64: []string{"-m", "6144", "-usbdevice", "tablet", "-fda", "/tmp/packer651374824", "-cdrom", "/files/packer-itcloud/ISO/en_windows_7_enterprise_with_sp1_x64_dvd_620201.iso", "-vnc", "127.0.0.1:10", "-machine", "type=pc,accel=kvm", "-device", "virtio-scsi-pci,id=scsi0", "-device", "scsi-hd,bus=scsi0.0,drive=drive0", "-device", "virtio-net,netdev=user.0", "-drive", "if=none,file=VM/Win7-qemu/Win7.qcow2,id=drive0,cache=unsafe,discard=ignore,format=qcow2", "-name", "Win7.qcow2", "-netdev", "user,id=user.0,hostfwd=tcp::3889-:5985", "-boot", "once=d"}

Seems like the -device arguments for scsi disks still get wiped even after this code change.

[hashibot[bot]]

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