Re: [libvirt-users] libvirtError: block copy still active: disk not ready for pivot yet

On Wed, Dec 28, 2016 at 01:26:12PM +0200, Ala Hino wrote: > Hi guys, > > When performing live merge, in few cases, we see the following exception: [...] > libvirtError: block copy still active: disk 'vdb' not ready for pivot yet You can see if the block operation is still in progress or not by doing: `sudo virsh blockjob vm1 vdb --info`. > That exception observed in following BZs: > > https://bugzilla.redhat.com/1376580 > https://bugzilla.redhat.com/1397122 [I see, that the above are oVirt bugs.] > I am trying to understand what this exception indicates in order to handle > it appropriately when thrown by libvirt. Here's the commit that adds the above error message. In short: Until the 'query-block-jobs' QMP command emits the flag BLOCK_JOB_READY, the copy / mirror block operation is truly not complete. commit eae59247c59aa02147b2b4a50177e8e877fdb218 Author: Peter Krempa <pkrempa(a)redhat.com&gt; Date: Wed Jul 15 15:11:02 2015 +0200 qemu: Update state of block job to READY only if it actually is ready Few parts of the code looked at the current progress of and assumed that a two phase blockjob is in the _READY state as soon as the progress reached 100% (info.cur == info.end). In current versions of qemu this assumption is invalid and qemu exposes a new flag 'ready' in the query-block-jobs output that is set to true if the job is actually finished. This patch adds internal data handling for reading the 'ready' flag and acting appropriately as long as the flag is present. While this still doesn't fix the virsh client problem with two phase block jobs and the --pivot option, it at least improves the error message: $ virsh blockcommit --wait --verbose vm vda --base vda[1] --active --pivot Block commit: [100 %]error: failed to pivot job for disk vda error: internal error: unable to execute QEMU command 'block-job-complete': The active block job for device 'drive-virtio-disk0' cannot be completed to $ virsh blockcommit --wait --verbose VM vda --base vda[1] --active --pivot Block commit: [100 %]error: failed to pivot job for disk vda error: block copy still active: disk 'vda' not ready for pivot yet [...] -- /kashyap