misc/148490: zpool attach - resilver bidirectionally, and reports incorrect time

[Alvin Poon <aspoon <at> gmail]

>Number:         148490
>Category:       misc
>Synopsis:       zpool attach - resilver bidirectionally, and reports incorrect time
>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:   Sun Jul 11 05:10:06 UTC 2010
>Closed-Date:
>Last-Modified:
>Originator:     Alvin Poon
>Release:        8.0-RELEASE-p3
>Organization:
>Environment:
FreeBSD host.domain 8.0-RELEASE-p3 FreeBSD 8.0-RELEASE-p3 #0: Tue May 25 20:54:11 UTC 2010     root at amd64-builder.daemonology.net:/usr/obj/usr/src/sys/GENERIC  amd64

>Description:
I just attached an unused ZFS (version 14) disk to another (version 13) to form a mirror, supposedly destroying the old disk.  However, zpool resilver went bidirectionally, and reported incorrect time both during and after completion:

$ zpool status
  pool: mypool
 state: ONLINE
 scrub: resilver completed after 307445734561825858h7m with 0 errors on Sun Jul 11 05:44:51 2010
config:

        NAME        STATE     READ WRITE CKSUM
        mypool      ONLINE       0     0     0
          mirror    ONLINE       0     0     0
            ad4     ONLINE       0     0     0  528M resilvered
            ad6     ONLINE       0     0     0  1.11T resilvered

errors: No known data errors
$


1. Resilver time should not be 307445734561825858h7m
2. zpool resilver should be unidirectional (from "master" to "slave"), why did it resilvered both ways (528M and 1.11T)?
>How-To-Repeat:

>Fix:


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