Commit 462c12d9 authored by Jim Harris's avatar Jim Harris Committed by Changpeng Liu
Browse files

iscsi: free pdus in hot remove path with no lun 



The datain handling code path will set the LUN to
NULL if it finds a task's LUN has been hotremoved.
This could happen before the iscsi hotplug routine
actually gets a chance to run.  If this happens,
one of these tasks doesn't actually get freed, and
then will be freed after the lun is closed -
causing a segfault in the bdev layer since it may
have a bdev_io associated with it.

Found by running the iscsi_tgt/fio test after
applying the next patch in this series.

There's more work needed in this hot remove clean up
path - currently we are just freeing a lot of PDUs
rather than completing them with error status when
a LUN is hot removed.  But let's tackle that
separately.

Signed-off-by: default avatarJim Harris <james.r.harris@intel.com>
Change-Id: I8d27f0c7a79ae91cb6504e5ff6ffc8e346c9e54c

Reviewed-on: https://review.gerrithub.io/c/spdk/spdk/+/455460


Tested-by: default avatarSPDK CI Jenkins <sys_sgci@intel.com>
Reviewed-by: default avatarBen Walker <benjamin.walker@intel.com>
Reviewed-by: default avatarShuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>
Reviewed-by: default avatarChangpeng Liu <changpeng.liu@intel.com>
parent 151a357c

lib/iscsi/conn.c

+7 −1
Original line number Diff line number Diff line
@@ -624,7 +624,13 @@ _iscsi_conn_remove_lun(void *arg1, void *arg2) 


	spdk_clear_all_transfer_task(conn, lun, NULL);

	TAILQ_FOREACH_SAFE(pdu, &conn->write_pdu_list, tailq, tmp_pdu) {

		if (pdu->task && (lun == pdu->task->scsi.lun)) {

		/* If the pdu's LUN matches the LUN that was removed, free this

		 * PDU immediately.  If the pdu's LUN is NULL, then we know

		 * the datain handling code already detected the hot removal,

		 * so we can free that PDU as well.

		 */

		if (pdu->task &&

		    (lun == pdu->task->scsi.lun || NULL == pdu->task->scsi.lun)) {

			TAILQ_REMOVE(&conn->write_pdu_list, pdu, tailq);

			spdk_iscsi_conn_free_pdu(conn, pdu);

		}