Re: [libvirt] [PATCH 2/3] qemu: improve device flag parsing

[replying to myself] On 01/18/2011 08:16 AM, Eric Blake wrote: I may have reproduced your problem. With a Fedora 13 VM (no nested kvm support), I see: $ qemu -version QEMU PC emulator version 0.12.5 (qemu-kvm-0.12.5), Copyright (c) 2003-2008 Fabrice Bellard $ qemu-kvm -device pci-assign,? open /dev/kvm: No such file or directory Could not initialize KVM, will disable KVM support property "pci-assign.?" not found can't set property "?" to "on" for "pci-assign" $ echo $? 1 $ qemu -device pci-assign,? The pci-assign device has not been found $ echo $? 1 $ qemu -device ? name "pci-bridge", bus PCI ... name "isabus-bridge", bus System, no-user $ echo ? 1 $ qemu -device pci-bridge,? property "pci-bridge.?" not found can't set property "?" to "on" for "pci-bridge" $ echo ? 1 Looks like -device was added in qemu 0.12.x, but device-specific property parsing via -device name,? wasn't added until 0.13.x. Furthermore, -device ? works in both versions to list available devices, but in 0.12.x it always makes qemu fail with non-zero status (which we can probably safely ignore). Thankfully, this is reflected in -help output: 0.12.5: -device driver[,options] add device -name ... 0.13.0: -device driver[,prop[=value][,...]] add device (based on driver) prop=value,... sets driver properties use -device ? to print all possible drivers use -device driver,? to print all possible properties File ... In fact, rather than keying off of QEMUD_CMD_FLAG_DEVICE (which is whether -device is present at all) to call qemuCapsExtractDeviceStr, it may be as simple as keying off of "-device driver,?" in the -help output. Patch coming up shortly... -- Eric Blake eblake(a)redhat.com +1-801-349-2682 Libvirt virtualization library http://libvirt.org