linux/include/target
Nicholas Bellinger dff0ca9ea7 target: Fix ordered task target_setup_cmd_from_cdb exception hang
If a command with a Simple task attribute is failed due to a Unit
Attention, then a subsequent command with an Ordered task attribute
will hang forever.  The reason for this is that the Unit Attention
status is checked for in target_setup_cmd_from_cdb, before the call
to target_execute_cmd, which calls target_handle_task_attr, which
in turn increments dev->simple_cmds.

However, transport_generic_request_failure still calls
transport_complete_task_attr, which will decrement dev->simple_cmds.
In this case, simple_cmds is now -1.  So when a command with the
Ordered task attribute is sent, target_handle_task_attr sees that
dev->simple_cmds is not 0, so it decides it can't execute the
command until all the (nonexistent) Simple commands have completed.

Reported-by: Michael Cyr <mikecyr@linux.vnet.ibm.com>
Tested-by: Michael Cyr <mikecyr@linux.vnet.ibm.com>
Reported-by: Bryant G. Ly <bryantly@linux.vnet.ibm.com>
Tested-by: Bryant G. Ly <bryantly@linux.vnet.ibm.com>
Cc: stable@vger.kernel.org # 4.4+
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2016-07-20 00:58:38 -07:00
..
iscsi cxgbit: Use type ISCSI_CXGBIT + cxgbit tpg_np attribute 2016-05-16 22:23:59 -07:00
target_core_backend.h target: Fix max_unmap_lba_count calc overflow 2016-07-20 00:58:36 -07:00
target_core_base.h target: remove sess_kref and ->shutdown_session 2016-05-10 01:19:49 -07:00
target_core_fabric.h target: Fix ordered task target_setup_cmd_from_cdb exception hang 2016-07-20 00:58:38 -07:00