target: Prevent cmd->se_queue_node double add
This patch addresses a bug with the lio-core-2.6.git conversion of
transport_add_cmd_to_queue() to use a single embedded list_head, instead
of individual struct se_queue_req allocations allowing a single se_cmd to
be added to the queue mulitple times. This was changed in the following:
commit 2a9e4d5ca5d99f4c600578d6285d45142e7e5208
Author: Andy Grover <agrover@redhat.com>
Date: Tue Apr 26 17:45:51 2011 -0700
target: Embed qr in struct se_cmd
The problem is that some target code still assumes performing multiple
adds is allowed via transport_add_cmd_to_queue(), which ends up causing
list corruption in qobj->qobj_list code. This patch addresses this
by removing an existing struct se_cmd from the list before the add, and
removes an unnecessary list walk in transport_remove_cmd_from_queue()
It also changes cmd->t_transport_queue_active to use explict sets intead
of increment/decrement to prevent confusion during exception path handling.
Signed-off-by: Roland Dreier <roland@purestorage.com>
Cc: Andy Grover <agrover@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Nicholas Bellinger <nab@risingtidesystems.com>
diff --git a/drivers/target/target_core_tmr.c b/drivers/target/target_core_tmr.c
index 662473c..98b12a8 100644
--- a/drivers/target/target_core_tmr.c
+++ b/drivers/target/target_core_tmr.c
@@ -339,7 +339,7 @@
atomic_dec(&cmd->t_transport_queue_active);
atomic_dec(&qobj->queue_cnt);
- list_del(&cmd->se_queue_node);
+ list_del_init(&cmd->se_queue_node);
spin_unlock_irqrestore(&qobj->cmd_queue_lock, flags);
pr_debug("LUN_RESET: %s from Device Queue: cmd: %p t_state:"