Checklist crnext

What is implemented

* open regular files and directories:
  * ext2, ext3, ext4
* /dev/null, zero, random, urandom
* epoll fd's
* event fd's
* timer fd's
* signal fd's
* unix sockets
* ipv4 sockets (except time-wait sockets)
* SYSV IPC (message queues, semaphores, and shared memory)
  * except semaphore undo
* Unix98 ptys
* futexes
* process ids
* credentials (userid, group, and POSIX capabilities)
* Smack LSM labels
* pipes
* FIFOs
* signals
* multiple processes, threads
* nested namespaces of:
  * user
  * IPC
  * UTS (hostname)
  * IPC
  * (nested pid namespaces only require userspace support)

What is NOT implemented (please make each a link to a page describing issues, a design for solving, how we will detect it to refuse checkpoint if we will not support it, and "how ugly it will make the kernel". The table summarizes these details. )

Not Implemented	Refuses to Checkpoint (Yes/No)	Anticipated Solution Impact
mounts	Yes
network devices, time-wait inet sockets	Yes
unlinked files and directories	Yes
inotify	Yes	Probably gross due to watches attaching to inodes
FUSE	Yes	Clean but requires per-FUSE-filesystem support
network and distributed filesystems	Yes
SYSV IPC: semaphore undo	No	Small, clean
netlink	Yes
new, expiremental, and/or infrastructure-oriented network protocols	Yes
file locks	Yes
file leases	Yes
fowner+sigio	Yes
ptraced tasks	Yes
time namespace	N/A
restart of 64-bit task from 32-bit task and vice versa	Yes
inet6 sockets (previously supported, just need to add it back in. minor)	Yes
Hardware devices other than those mentioned above. Includes mmap, /dev/foo, Infiniband devices	Yes (mostly)
System-specific files in sysfs (things like UUID files)	Yes