Am 04.04.2017 um 17:35 hat Kevin Wolf geschrieben: > Usually guest devices don't like other writers to the same image, so > they use blk_set_perm() to prevent this from happening. In the migration > phase before the VM is actually running, though, they don't have a > problem with writes to the image. On the other hand, storage migration > needs to be able to write to the image in this phase, so the restrictive > blk_set_perm() call of qdev devices breaks it. > > This patch flags all BlockBackends with a qdev device as > blk->disable_perm during incoming migration, which means that the > requested permissions are stored in the BlockBackend, but not actually > applied to its root node yet. > > Once migration has finished and the VM should be resumed, the > permissions are applied. If they cannot be applied (e.g. because the NBD > server used for block migration hasn't been shut down), resuming the VM > fails. > > Signed-off-by: Kevin Wolf <kw...@redhat.com>
Ciprian, can you give this patch a try and report back whether it fixes the storage migration bug you encountered? Kevin
