Commit 9a3ff01d7f (which was ACKed at
the end of January, but for some reason didn't get pushed until during
the 1.0.4 freeze) fixed the logic in virPCIGetVirtualFunctions().
Unfortunately, a typo in the fix (replacing VIR_REALLOC_N with
VIR_ALLOC_N during code movement) caused not only a memory leak, but
also resulted in most of the elements of the result array being
replaced with NULL. virNetDevGetVirtualFunctions() assumed (and I think
rightly so) that virPCIGetVirtualFunctions() wouldn't return any NULL
elements in the array, so it ended up segfaulting.
This was found when attempting to use a virtual network with an
auto-created pool of SRIOV VFs, e.g.:
<forward mode='hostdev' managed='yes'>
<pf dev='eth4'/>
</forward>
(the pool of PCI addresses is discovered by calling
virNetDevGetVirtualFunctions() on the PF dev).
virPCIGetVirtualFunctions returns 0 even if there is no "virtfn"
entry under the device sysfs path.
And virPCIGetVirtualFunctions returns -1 when it fails to get
the PCI config space of one VF, however, with keeping the
the VFs already detected.
That's why udevProcessPCI and gather_pci_cap use logic like:
if (!virPCIGetVirtualFunctions(syspath,
&data->pci_dev.virtual_functions,
&data->pci_dev.num_virtual_functions) ||
data->pci_dev.num_virtual_functions > 0)
data->pci_dev.flags |= VIR_NODE_DEV_CAP_FLAG_PCI_VIRTUAL_FUNCTION;
to tag the PCI device with "virtual_function" cap.
However, this results in a VF will aslo get "virtual_function" cap.
This patch fixes it by:
* Ignoring the VF which has failure of getting PCI config space
(given that the successfully detected VFs are kept , it makes
sense to not give up on the failure of one VF too) with a warning,
so virPCIGetVirtualFunctions will not return -1 except out of memory.
* Free the allocated *virtual_functions when out of memory
And thus the logic can be changed to:
/* Out of memory */
int ret = virPCIGetVirtualFunctions(syspath,
&data->pci_dev.virtual_functions,
&data->pci_dev.num_virtual_functions);
if (ret < 0 )
goto out;
if (data->pci_dev.num_virtual_functions > 0)
data->pci_dev.flags |= VIR_NODE_DEV_CAP_FLAG_PCI_VIRTUAL_FUNCTION;
To allow modifications to the lists to be synchronized, convert
virPCIDeviceList and virUSBDeviceList into virObjectLockable
classes. The locking, however, will not be self-contained. The
users of these classes will have to call virObjectLock/Unlock
in the critical regions.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Pass stub driver name directly to pciDettachDevice and pciReAttachDevice to fit
for different libvirt drivers. For example, qemu driver prefers pci-stub, but
Xen prefers pciback.
Signed-off-by: Chunyan Liu <cyliu@suse.com>
