Panic on removing corrupted file on zfs

[Ben Stuyts]

Hello,

I have a corrupted file on a zfs file system. It is a backup store for an rsync job, and rsync errors with:

rsync: failed to read xattr rsync.%stat for "/home1/vwa/rsync/tank3/cam/jpg/487-20150224180950-05.jpg": Input/output error (5)
Corrupt rsync.%stat xattr attached to "/home1/vwa/rsync/tank3/cam/jpg/487-20150224180950-04.jpg": "100644 0,0 \#007:1001"
rsync error: error in file IO (code 11) at xattrs.c(1003) [generator=3.1.1]

This is a file from februari, and it hasn’t changed since. Smartctl shows no errors. No ECC memory on this system, so maybe caused by a memory problem. I am currently running a scrub for the second time. First time didn’t help.

Output from zpool status -v:

  pool: home1
 state: ONLINE
status: One or more devices has experienced an error resulting in data
	corruption.  Applications may be affected.
action: Restore the file in question if possible.  Otherwise restore the
	entire pool from backup.
   see: http://illumos.org/msg/ZFS-8000-8A
  scan: scrub in progress since Tue Jun 23 15:37:31 2015
        462G scanned out of 2.47T at 80.8M/s, 7h16m to go
        0 repaired, 18.29% done
config:

	NAME                                          STATE     READ WRITE CKSUM
	home1                                         ONLINE       0     0     0
	  gptid/14032b0b-7f05-11e3-8797-54bef70d8314  ONLINE       0     0     0

errors: Permanent errors have been detected in the following files:

        /home1/vwa/rsync/tank3/cam/jpg/487-20150224180950-05.jpg/<xattrdir>

When I try to rm the file the system panics. From /var/crash:

tera8 dumped core - see /var/crash/vmcore.1

Tue Jun 23 15:37:11 CEST 2015

FreeBSD tera8 10.1-STABLE FreeBSD 10.1-STABLE #2 r284317: Fri Jun 12 17:07:21 CEST 2015     root at tera8:/usr/obj/usr/src/sys/GENERIC  amd64

panic: acl_from_aces: a_type is 0x4d00

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Unread portion of the kernel message buffer:
panic: acl_from_aces: a_type is 0x4d00
cpuid = 1
KDB: stack backtrace:
#0 0xffffffff8097d890 at kdb_backtrace+0x60
#1 0xffffffff809410e9 at vpanic+0x189
#2 0xffffffff80940f53 at panic+0x43
#3 0xffffffff81aaa209 at acl_from_aces+0x1c9
#4 0xffffffff81b61546 at zfs_freebsd_getacl+0xa6
#5 0xffffffff80e5de77 at VOP_GETACL_APV+0xa7
#6 0xffffffff809c7a3c at vacl_get_acl+0xdc
#7 0xffffffff809c7bd2 at sys___acl_get_link+0x72
#8 0xffffffff80d35817 at amd64_syscall+0x357
#9 0xffffffff80d1a89b at Xfast_syscall+0xfb

Is there any other way of getting rid of this file (except destroying the fs/pool)? 

Thanks,
Ben