Stable from May 31 - zfs list locked

[Danny Braniss]

> Hello,
> 
> I encounter this problem for the second time. The system is working 
> perfectly well but suddenly the command `zfs list' don't work and can't 
> be killed.
> 
> Here is a procstat of the culprit:
> 
> [root at morzine ~]# procstat -k 91766
>    PID    TID COMM             TDNAME           KSTACK 
> 
> 91766 100490 zfs              -                mi_switch sleepq_switch 
> sleepq_wait _cv_wait zio_wait dbuf_read dmu_buf_hold zap_lockdir 
> zap_lookup_norm zap_lookup dsl_prop_get_dd dsl_dataset_get_ref 
> dsl_dataset_hold dmu_objset_open zfs_ioc_objset_stats zfsdev_ioctl 
> devfs_ioctl_f kern_ioctl
> 
> same thing happen if I try to run `zpool list' un another terminal.
> 
> Henri

same here, but with a twist:
it used to happen on a 7.1, then after an unpgrade, sometime in April,
to 7.2-PRERELEASE, things were ok till today!
I was about to blame a resent upgrade of the PERC firmware(a very long shot :-),
but now I don't know if upgradeing to 7.2-stable will help. This is a
production host, with 12TB serving many nfs clients.

danny