Hang on mount with kernel 4.7.x or newer with 0.6.5.8

[satmandu]

I'm using the stock ubuntu yakkety (dev) 0.6.5.8 release, and I have a volume that mounts just fine when using a 4.6.x kernel with that version of zfsonlinux.

When I use a 4.7.x or 4.8.x (linux-signed-image-4.8.0-11-generic is now available in the ubuntu dev pool) kernel, the system hangs at:

Starting Import ZFS pools by cache file.
Starting Mount ZFS Filesystems...
A start job is running for Mount ZFS filesystems (time / no limit)
INFO: task zfs:3907 blocked for more than 120 seconds.

(I have to eventually hit ctrl-alt-del to reboot.)

I imagine that this trouble report is pretty close to less than useless to help debug. What information can I provide to help fix this issue?

[behlendorf]

By chance have you set casesensitivity=insensitive, if so this may be a duplicate of #5124. There's a proposed fix in #5141, if you could verify it resolves the issue that would be very helpful.

[satmandu]

I DO have casesensitivity=insensitive on that volume!

[satmandu]

That patch doesn't work against the 0.6.5.8 branch, so I'll wait to test a version that does. :)