4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Nicholas Bellinger <nab@xxxxxxxxxxxxxxx> commit 527268df31e57cf2b6d417198717c6d6afdb1e3e upstream. This patch fixes a regression in >= v4.1.y code where the original SCF_ACK_KREF assignment in target_get_sess_cmd() was dropped upstream in commit 054922bb, but the series for addressing TMR ABORT_TASK + LUN_RESET with fabric session reinstatement in commit febe562c20 still depends on this code in transport_cmd_finish_abort(). The regression manifests itself as a se_cmd->cmd_kref +1 leak, where ABORT_TASK + LUN_RESET can hang indefinately for a specific I_T session for drivers using SCF_ACK_KREF, resulting in hung kthreads. This patch has been verified with v4.1.y code. Reported-by: Vaibhav Tandon <vst@xxxxxxxxx> Tested-by: Vaibhav Tandon <vst@xxxxxxxxx> Cc: Vaibhav Tandon <vst@xxxxxxxxx> Signed-off-by: Nicholas Bellinger <nab@xxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/target/target_core_transport.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/drivers/target/target_core_transport.c +++ b/drivers/target/target_core_transport.c @@ -2509,8 +2509,10 @@ int target_get_sess_cmd(struct se_cmd *s * fabric acknowledgement that requires two target_put_sess_cmd() * invocations before se_cmd descriptor release. */ - if (ack_kref) + if (ack_kref) { kref_get(&se_cmd->cmd_kref); + se_cmd->se_cmd_flags |= SCF_ACK_KREF; + } spin_lock_irqsave(&se_sess->sess_cmd_lock, flags); if (se_sess->sess_tearing_down) { -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html