ZFS import panic (kgdb backtrace attached)

[grarpamp]

On Tue, Jun 10, 2014 at 11:58 AM, John Baldwin <jhb at freebsd.org> wrote:
> Can you do 'frame 7' and 'p *rt' and 'p *rt->rt_ops'?

(kgdb) frame 7
#7  0xc13cb9f4 in range_tree_vacate (rt=0xc83dc000, func=0, arg=0x0)
    at /.../src/sys/modules/zfs/../../cddl/contrib/opensolaris/uts/common/fs/zfs/range_tree.c:364
364                     rt->rt_ops->rtop_vacate(rt, rt->rt_arg);
(kgdb) p *rt
$1 = {rt_root = {avl_root = 0xd6900780, avl_compar = 0xc13cb890
<range_tree_seg_compare>, avl_offset = 0, avl_numnodes = 1, avl_size =
48},
  rt_space = 4294967296, rt_ops = 0x1, rt_arg = 0x0, rt_histogram = {0
<repeats 64 times>}, rt_lock = 0xc8309000}
(kgdb) p *rt->rt_ops
Cannot access memory at address 0x1