Re: [libvirt] [PATCH] qemu: default to vfio for nodedev-detach

This patch resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1035188 Commit f094aaac48a6 changed the PCI device assignment in qemu domains to default to using VFIO rather than legacy KVM device assignment (when VFIO is available). It didn't change which driver was used by default for virNodeDeviceDetachFlags(), though, so that API (and the virsh nodedev-detach command) was still binding to the pci-stub driver, used by legacy KVM assignment, by default. This patch publicizes (only within the qemu module, though, so no additions to the symbol exports are needed) the functions that check for presence of KVM and VFIO device assignment, then uses those functions to decide what to do when no driver is specified for virNodeDeviceDetachFlags(); if the vfio driver is loaded, the device will be bound to vfio-pci, or if legacy KVM assignment is supported on this system, the device will be bound to pci-stub; if neither method is avialable, the detach will fail.

--- src/qemu/qemu_driver.c | 19 ++++++++++++++++--- src/qemu/qemu_hostdev.c | 6 +++--- src/qemu/qemu_hostdev.h | 4 +++- 3 files changed, 22 insertions(+), 7 deletions(-)