misc/129539: ZFS Boot from single drive or mirror with raidz data pack

[Paul Wootton]

>Number:         129539
>Category:       misc
>Synopsis:       ZFS Boot from single drive or mirror with raidz data pack
>Confidential:   no
>Severity:       non-critical
>Priority:       medium
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Tue Dec 09 23:10:01 UTC 2008
>Closed-Date:
>Last-Modified:
>Originator:     Paul Wootton
>Release:        FreeBSD 8.0
>Organization:
>Environment:
FreeBSD wasp.caspersworld.co.uk 8.0-CURRENT FreeBSD 8.0-CURRENT #1: Sat Dec  6 22:49:23 UTC 2008     paul at wasp.caspersworld.co.uk:/usr/obj/usr/src/sys/WASP  amd64

>Description:
When booting from a single ZFS disk or mirror pack with a raidz pack also present, the system just cyclic boots with the following error

ZFS: can only boot from disk or mirror vdevs
ZFS: inconsistent nvlist contents

This is caused because we forgot to check the return code of vdev_init_from_nvlist(vdevs, &top_vdev) from with the vdev_probe() function in /usr/src/sys/boot/zfs/zfsimple.c on line 726
>How-To-Repeat:
Set up bootable ZFS single drive or mirror pack and then introduce a raidz pack as well
>Fix:
Check the return code of vdev_init_from_nvlist(vdevs, &top_vdev) from with the vdev_probe() function in /usr/src/sys/boot/zfs/zfsimple.c on line 726

Patch attached with submission follows:

*** zfsimpl.c	Wed Nov 19 16:59:19 2008
--- zfsimpl.c.fix	Tue Dec  9 22:48:36 2008
***************
*** 721,731 ****
  	if (nvlist_find(nvlist,
  			ZPOOL_CONFIG_VDEV_TREE,
  			DATA_TYPE_NVLIST, 0, &vdevs)) {
  		return (EIO);
  	}
! 	vdev_init_from_nvlist(vdevs, &top_vdev);
  
  	/*
  	 * Add the toplevel vdev to the pool if its not already there.
  	 */
  	STAILQ_FOREACH(pool_vdev, &spa->spa_vdevs, v_childlink)
--- 721,733 ----
  	if (nvlist_find(nvlist,
  			ZPOOL_CONFIG_VDEV_TREE,
  			DATA_TYPE_NVLIST, 0, &vdevs)) {
  		return (EIO);
  	}
! 	int initRetVal = vdev_init_from_nvlist(vdevs, &top_vdev);
! 	if(initRetVal)
! 		return initRetVal;
  
  	/*
  	 * Add the toplevel vdev to the pool if its not already there.
  	 */
  	STAILQ_FOREACH(pool_vdev, &spa->spa_vdevs, v_childlink)


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