On 05/13/2010 09:52 AM, Daniel P. Berrange wrote:
When QEMU runs with its disk on NFS, and as a non-root user, the disk is chownd to that non-root user. When migration completes the last step is shutting down the QEMU on the source host. THis normally resets user/group/security label. This is bad when the VM was just migrated because the file is still in use on the dest host. It is thus neccessary to skip the reset step for any files found to be on a shared filesystem
* src/libvirt_private.syms: Export virStorageFileIsSharedFS * src/util/storage_file.c, src/util/storage_file.h: Add a new method virStorageFileIsSharedFS() to determine if a file is on a shared filesystem (NFS, GFS, OCFS2, etc)
Is this sufficient? Suppose I have the situation where on hypervisor A, the disk image is on a local drive, but that machine A also exports that directory via NFS. Then on hypervisor B, the disk image is viewed via NFS. When migrating a guest from machine A to B, the shutdown path on machine A will see that the file is on local storage, not NFS, and will not get your code exemption that avoids the relabel. -- Eric Blake eblake@redhat.com +1-801-349-2682 Libvirt virtualization library http://libvirt.org