stable/7: shutdown stuck in zfs_umount (z_op_cnt > 0)

[Miroslav Lachman]

Andriy Gapon wrote:
> Quite frequently when rebooting or shutting down after long uptime my amd64
> stable/7 system gets stuck in shutdown after printing "All buffers synced".
> Below is some kgdb examination after breaking to ddb and inducing panic.
> I also see lots of threads with zfs-related names (also below).
> Any ideas/suggestions on cause/fix/workaround?
> Thanks!

Just "me too" with amd64 7-STABLE (pre 7.2-RELEASE) and onetime with 
7.2-RC1 i386 in Qemu session (also with ZFS mounted filesystem)

Miroslav Lachman