kern/141010: "zfs scrub" fails when backed by files in UFS2

[Gerald Gutierrez]

>Number:         141010
>Category:       kern
>Synopsis:       "zfs scrub" fails when backed by files in UFS2
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Mon Nov 30 01:50:00 UTC 2009
>Closed-Date:
>Last-Modified:
>Originator:     Gerald Gutierrez
>Release:        8.0-RELEASE
>Organization:
>Environment:
FreeBSD 8.0-RELEASE Freebsd 8.0-RELEASE #0: Sat Nov 21 15:02:08 UTC 2009 root at masoncse.buffalo.edu:/usr/obj/usr/src/sys/GENERIC amd64
>Description:

"zfs scrub" causes kernel panic with FreeBSD 8.0-RELEASE amd64.


Test system installed via VMware Fusion 3.0 using 1 processor and 2GB of RAM. Several parameters for vm.kmem_size, vm.kmem_size_max were tried with no differences.

The panic doesn't seem to happen if ZFS is backed by IDE hard drives.

>How-To-Repeat:

After clean install, added "zfs_enable=YES" to /etc/rc.conf. Went through ZFS tutorial at: http://flux.org.uk/howto/solaris/zfs_tutorial_01. This creates two 128MB files and creates a ZFS mirror pool backed by the two files. Tutorial then tries to demonstrate a ZFS failure mode. Commands as follows:

zpool create trout mirror /home/ocean/disk1 /home/ocean/disk2
mkfile 32m /trout/foo
dd if=/dev/random of=/home/ocean/disk1 bs=512 count=1
zpool scrub trout

At this point, the kernel panics.
>Fix:


>Release-Note:
>Audit-Trail:
>Unformatted: