Re: [libvirt] [PATCH 2/2] qemu: migration: Ignore null ptr in qemuMigrationStopNBDServer

On 11/03/2014 05:22 AM, weiwei li wrote: > mig->nbd is initialized by qemuMigrationCookieXMLParse（called > by qemuMigrationEatCookie），with a condition that > the nbd infomation contained in Cookie string. I found in debug info > that qemuMigrationStartNBDServer had been called in > qemuMigrationPrepareAny（mig->nbd not null）, but at > in qemuMigrationFinish qemuMigrationStopNBDServer can not really > stop nbd server bucause mig->nbd is not initialized(that is because cookie > string does not contain nbd information ). > > so ,there are two solutions: > 1 qemuMigrationStopNBDServer ignore mig->nbd null ptr > 2 add cookie info for nbd same stage (that is lost in which stage i am not sure~ ) > > I choose an easy way solution 1 with least code changing， maybe is not google > way ：） > > cookie log is like this: > 2014-10-30 08:38:14.106+0000: 15078: debug : qemuMigrationRun:3254 : > driver=0x7f936413cd40, vm=0x7f934400b850, cookiein=<qemu-migration> > <name>3cd4c349-e058-4a1a-8b3d-cc988efd11e2</name> > <uuid>3cd4c349-e058-4a1a-8b3d-cc988efd11e2</uuid> > <hostname>50e54929-059c-ffff-ffff-ffffffffffff_10.180.39.36</hostname> > <hostuuid>50e54929-059c-ffff-ffff-ffffffffffff</hostuuid> > <nbd port='49153'/> > </qemu-migration> > > 2014-10-30 08:39:12.527+0000: 15076: debug : virObjectRef:296 : OBJECT_REF: > obj=0x7f9364138880 > 2014-10-30 08:39:12.527+0000: 15076: debug : qemuMigrationFinish:4507 : > driver=0x7f936413cd40, dconn=0x7f9358002720, vm=0x7f935c002da0, > cookiein=<qemu-migration> > <name>3cd4c349-e058-4a1a-8b3d-cc988efd11e2</name> > <uuid>3cd4c349-e058-4a1a-8b3d-cc988efd11e2</uuid> > <hostname>50e54929-059c-ffff-ffff-ffffffffffff_10.180.39.36</hostname> > <hostuuid>50e54929-059c-ffff-ffff-ffffffffffff</hostuuid> > <feature name='persistent'/> ... > <memballoon model='virtio'> > <address type='pci' domain='0x0000' bus='0x00' slot='0x06' > function='0x0'/> > </memballoon> > </devices> > </domain> > <nbd/> So the <nbd/> element is there, we just don't parse it because qemuMigrationFinish calls qemuMigrationEatCookie without the QEMU_MIGRATION_COOKIE_NBD flag. I believe the proper fix is to add this flag there. Jan > </qemu-migration> > , cookieinlen=2567, cookieout=0x7f93722eab08, cookieoutlen=0x7f93722eab14, > flags=289, retcode=0 >