Description of problem:
when setting io mode to default in virt-manager for block device,should automatic attach io=native to guest
Version-Release number of selected component (if applicable):
Steps to Reproduce:
1.install guest with a block device.
#virsh dumpxml demo
<disk type='block' device='disk'>
<driver name='qemu' type='raw' cache='none' io='native'/>
<target dev='hdb' bus='ide'/>
<address type='drive' controller='0' bus='0' unit='1'/>
the io mode set to native automatic.
2.shutdown the guest ,in virt-manager ,switch to guest detail page
3.change io mode to default and apply
4.start the guest
in guest xml,io='native' removed,
#ps -ef | grep qemu-kvm
aio=native removed from block device
the qemu default io mode is threads,actually block device default mode is native,
so should add io='native' when setting default mode for block device
Hmm, we have usually had 'default' mean 'hypervisor default' so the behavior is consistent, but I agree it's a bit misleading.
Not urgent, and given reduced capacity for virt-manager/virtinst, just moving
this to the upstream tracker.
Actually, reconsidering, this is the best we can do, short of having libvirt and qemu report default capabilities to us. Trying to hardcode what the default is just causes maintenance pain, especially in this case when it isn't having any effect on actual configuration. Closing as WONTFIX.