Re: [libvirt] [PATCHv3 08/43] snapshot: avoid crash when deleting qemu snapshots

On 08/24/2011 10:38 AM, Daniel P. Berrange wrote: > On Wed, Aug 24, 2011 at 09:22:25AM -0600, Eric Blake wrote: >> This one's nasty. Ever since we fixed virHashForEach to prevent >> nested hash iterations for safety reasons, virDomainSnapshotDelete >> with VIR_DOMAIN_SNAPSHOT_DELETE_CHILDREN has been broken for qemu: >> it deletes children, while leaving grandchildren intact but pointing >> to a no-longer-present parent. But even before then, the code would >> often appear to succeed to clean up grandchildren, but risked memory >> corruption if you have a large and deep hierarchy of snapshots. >> > I also still saw errors in libvirtd logs > > 17:36:36.175: 4423: info : libvirt version: 0.9.4 > 17:36:36.175: 4423: error : virHashSearch:604 : Hash operation not > allowed during iteration > 17:36:36.176: 4423: warning : virDomainSnapshotMarkDescendant:11309 : > snapshot hash table is inconsistent! Ouch; I can reproduce. I guess I didn't test this one as thoroughly as I had planned, and this is indeed a bug in my 'forEachDescendant' iterator. I'll post an update once I figure out where I went wrong.