Re: [libvirt] [PATCH] fix the failure of nodedev-reattach caused by the variables from nodedev-attach
On 07/01/2011 11:30 PM, ghostwcy wrote:
At 2011-7-1 18:24, Guannan Ren write:
> the "virsh nodedev-reattch" command could return successfully, but
> the pci device is still
> bound to pci-stub driver. The reason is noddev-reattach trys to use
> the variables set by
> nodedev-dettach commands. Becuase these variables is not persistent,
> this is not we expected.
> the patch try to fix it.
I do not agree with this patch. You should read this mail:
https://www.redhat.com/archives/libvir-list/2011-April/msg00315.html
This patch will cause regression about hotpluging host pci device.
I think the problem is that: the init value of these variables is wrong.
We can fix this bug by modifing pciGetDevice() or its caller.
>
I read the patch, it introduced the mechanism to check whether
the device is bound to
pci-stub when we write dev-id to new_id if a new device with this ID
is hotpluggged, or if
a probe is triggered for such a device, I think my patch kept it
working.
The overall idea is as follows:
If the device is already bound to pci-stub, then do nothing.
If not, try to write dev-id to "new_id", then check the
state of its driver(hotplug issue)
Unbind from its original driver , then bind to pci-stub driver
Anyway, we should write dev-id to "remove_id" to protect
the device from causing
problems when reattaching it.
About fixing the problem from pciGetDevice(), unless we feedback
the state of pci device to
libvirtd but I don't think it is easier.