### Please describe the problem.

Running "git annex add" on a file of any size (whether 10KB or 1GB) hangs forever, must be killed with ^C, and does not add the file.

"git annex unannex" still works, as do other commands like "git annex status", "git annex whereis", etc.

### What steps will reproduce the problem?

Running "git annex add" from this computer on any git annex repository on any hard drive.

### What version of git-annex are you using? On what operating system?

I am using 3.20121127 on Arch Linux with git version 1.8.5.2.

My hard drive has several gigabytes of free space, and I have no trouble using git itself for development in other repositories.

I have been using this for over a year with no problem; I first noticed this about a week ago, and it must have started within the last ~3 weeks at most.


### Please provide any additional information below.

[[!format sh """
# If you can, paste a complete transcript of the problem occurring here.
# If the problem is with the git-annex assistant, paste in .git/annex/daemon.log

$git annex add test.txt
add test.txt 

# End of transcript or log.
"""]]

> [[done]]
