Change in vdsm[master]: sriov: Make the hook safe for concurrency

asegurap at redhat.com asegurap at redhat.com
Sat Apr 6 00:43:56 UTC 2013


Antoni Segura Puimedon has posted comments on this change.

Change subject: sriov: Make the hook safe for concurrency
......................................................................


Patch Set 1:

I keep the verification +1 and I add a funny bit of information.

The reservation release by not-owner I mentioned earlier matters even less because the sequence of events is:

1.- VM1 is created with p1p1_1 and p1p1_2, reservations for both are created and /sys/class/net/p1p1_1/resour* are chowned to qemu:qemu for attach to qemu.
2.- VM2 is fails to created with p1p1_1 and p1p1_2.
3.- Admin destroys VM2 and hook after destroy is invoked.
4.- after_vm_destroy of VM2 deletes the reservation files and chowns the devices' resources back to root using a file path of this kind /sys/devices/pci0000:00/0000:00:01.0/0000:02:10.2
5.- Even after the chowning back to root, the passed through devices continue to work fine on VM1.


It seems that the chowning was only really necessary for attaching to qemu.

TL;DR: chowning only needed for attaching to Qemu process. Race I mentioned before is inconsequential.

--
To view, visit http://gerrit.ovirt.org/13641
To unsubscribe, visit http://gerrit.ovirt.org/settings

Gerrit-MessageType: comment
Gerrit-Change-Id: I2c6ad7f2ee53911312700396000e0aca07a917e9
Gerrit-PatchSet: 1
Gerrit-Project: vdsm
Gerrit-Branch: master
Gerrit-Owner: Antoni Segura Puimedon <asegurap at redhat.com>
Gerrit-Reviewer: Antoni Segura Puimedon <asegurap at redhat.com>
Gerrit-Reviewer: Dan Kenigsberg <danken at redhat.com>
Gerrit-Reviewer: Dan Yasny <dyasny at redhat.com>
Gerrit-Reviewer: Mark Wu <wudxw at linux.vnet.ibm.com>
Gerrit-Reviewer: Shu Ming <shuming at linux.vnet.ibm.com>
Gerrit-Reviewer: oVirt Jenkins CI Server


More information about the vdsm-patches mailing list