svn commit: r264392 - head/sys/cddl/contrib/opensolaris/uts/common/fs/zfs

[Steven Hartland]

Interesting, I'd be curious to know what the panic for this looks like?

----- Original Message ----- 
From: "Davide Italiano" <davide at FreeBSD.org>


> Author: davide
> Date: Sun Apr 13 01:15:37 2014
> New Revision: 264392
> URL: http://svnweb.freebsd.org/changeset/base/264392
> 
> Log:
>  Fix a panic in zfs_rename().
>  this is due to a wrong dereference of a vnode when it's not locked and
>  can be (potentially) recycled. 'sdvp' cannot be locked on zfs_rename()
>  entry point because the VFS can't be sure that this scenario is
>  LOR-free (it might violate the parent->child lock acquisition rule).
>  Dereference 'tdvp' instead, which is already locked on entry, and access
>  'sdvp' fields only when it's safe, i.e. under ZFS_ENTER scope.
>  
>  While at it, remove the usage of VOP_REALVP, as long as this is a NOP
>  on FreeBSD.