Re: [libvirt] [PATCH 21/24] hostdev: Stop early if unmanaged devices have not been detached
On 03/07/2016 12:24 PM, Andrea Bolognani wrote:
Unmanaged devices, as the name suggests, are not detached
automatically from the host by libvirt before being attached to a
guest: it's the user's responsability to detach them manually
beforehand. If that preliminary step has not been performed, the
attach operation can't complete successfully.
Instead of relying on the lower layers to error out with cryptic
messages such as
error: Failed to attach device from /tmp/hostdev.xml
error: Path '/dev/vfio/12' is not accessible: No such file or directory
prevent the situation altogether and provide the user with a more
useful error message.
---
src/util/virhostdev.c | 7 +++++++
1 file changed, 7 insertions(+)
diff --git a/src/util/virhostdev.c b/src/util/virhostdev.c
index 03c3445..d1529c5 100644
--- a/src/util/virhostdev.c
+++ b/src/util/virhostdev.c
@@ -576,6 +576,13 @@ virHostdevPreparePCIDevices(virHostdevManagerPtr mgr,
mgr->inactivePCIHostdevs) < 0)
Is this in the right place?
Consider a few lines above:
/* Step 1: validate that non-managed device isn't in use, ...
Second question - how would the device get on the inactiveList
initially? Looking at virPCIDeviceListAdd calls for inactiveList.
'pcidevs' is the list of all devices both managed and unmanaged
'activeList' is populated in step 5 and virHostdevUpdateActivePCIDevices
'inactiveList' is populated in 'inactivedevs:' label, in step 2 of
virHostdevReAttachPCIDevices, and in virPCIDeviceDetach via
virPCIDeviceListAddCopy *if* the device is managed in step 2 of Prepare.
I don't disagree this is an important step, but it's the "how" we
determine this that I'm questioning.
John
goto reattachdevs;
} else {
+ if (!virPCIDeviceListFind(mgr->inactivePCIHostdevs, pci)) {
+ virReportError(VIR_ERR_OPERATION_INVALID,
+ _("Unmanaged PCI device %s must be manually "
+ "detached from the host"),
+ virPCIDeviceGetName(pci));
+ goto reattachdevs;
+ }
VIR_DEBUG("Not detaching unmanaged PCI device %s",
virPCIDeviceGetName(pci));
}