Root mount from ZFS takes forever...literally.

[Pawel Tyll]

Hi list,

Has this happened to anyone?

Boot process "hangs" on Trying to mount root from zfs:tank/root - I
can import the pool from alternate boot source (PXE), and access files
fine, but I can't finish booting the system from ZFS.

It's a recent 8-STABLE, it happened after upgrading from older
8-STABLE, but reverting to older kernel and modules doesn't solve
this, so maybe it's unrelated.

Cheers.