svn commit: r286985 - head/sys/cddl/contrib/opensolaris/uts/common/fs/zfs

[Andriy Gapon]

On 21/08/2015 11:17, Andriy Gapon wrote:
> Author: avg
> Date: Fri Aug 21 08:17:44 2015
> New Revision: 286985
> URL: https://svnweb.freebsd.org/changeset/base/286985
> 
> Log:
>   try to fix lor between z_teardown_lock and spa_namespace_lock
>   
>   The lock order reversal and a resulting deadlock were introduced
>   in r285021 / D2865.  The problem is that zfs_register_callbacks() calls
>   dsl_prop_get_integer() that has to acquire spa_namespace_lock.
>   At the same time, spa_config_sync() is called with spa_namespace_lock
>   held and then it performs ZFS vnode operations that acquire
>   z_teardown_lock in the reader mode.
>   
>   So, fix the problem by using dsl_prop_get_int_ds() instead of
>   dsl_prop_get_integer().  The former does not need to look up
>   the pool and the dataset by name.
>   
>   Reported by:	many
>   Reviewed by:	delphij
>   Tested by:	delphij, Jens Schweikhardt <schweikh at schweikhardt.net>
>   MFC after:	5 days
>   X-MFC with:	r285021

Differential Revision:	https://reviews.freebsd.org/D3281


-- 
Andriy Gapon