diff options
author | Richard W.M. Jones <rjones@redhat.com> | 2012-07-09 15:23:52 +0100 |
---|---|---|
committer | Richard W.M. Jones <rjones@redhat.com> | 2012-07-09 15:23:52 +0100 |
commit | 1cde66165aac222f1a07ad4c3873c61d49eabb02 (patch) | |
tree | 3f83b4205548e94cb53a8ac3331fbd6df44c3e81 /fuse/guestmount.pod | |
parent | b749dc70742e749dbd7c0c20e6e7191fdd199170 (diff) | |
download | libguestfs-1cde66165aac222f1a07ad4c3873c61d49eabb02.tar.gz libguestfs-1cde66165aac222f1a07ad4c3873c61d49eabb02.tar.xz libguestfs-1cde66165aac222f1a07ad4c3873c61d49eabb02.zip |
fuse: Document race condition possible with fusermount.
See also:
https://bugzilla.redhat.com/show_bug.cgi?id=835466#c9
Diffstat (limited to 'fuse/guestmount.pod')
-rw-r--r-- | fuse/guestmount.pod | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/fuse/guestmount.pod b/fuse/guestmount.pod index a0bc6f14..c37301c9 100644 --- a/fuse/guestmount.pod +++ b/fuse/guestmount.pod @@ -106,6 +106,22 @@ namespace using the Linux-specific L<clone(2)>/L<unshare(2)> flag C<CLONE_NEWNS>. Unfortunately at the moment this requires root and we would also probably need to add it as a feature to guestmount. +=head2 Race conditions possible when shutting down the connection + +When C<fusermount -u> exits, guestmount may still be running and +cleaning up the mountpoint. The disk image will not be fully +finalized. + +This means that scripts like the following have a nasty race +condition: + + guestmount -a disk.img -i /mnt + # copy things into /mnt + fusermount -u /mnt + # immediately try to use 'disk.img' <-- UNSAFE + +The solution is to spin waiting for the guestmount process to exit. + =head1 OPTIONS =over 4 |