scsi: qedi: Fix host removal with running sessions

qedi_clear_session_ctx() could race with the in-kernel or userspace driven
recovery/removal and we could access a NULL conn or do a double free.

We should be using iscsi_host_remove() to start the removal process from
the driver. It will start the in-kernel recovery and notify userspace that
the driver's scsi_hosts are being removed. iscsid will then drive the
session removal like is done when the logout command is run. When the
sessions are removed, iscsi_host_remove() will return so qedi can finish
knowing there are no running sessions and no new sessions will be allowed.

This also fixes an issue where we check for a NULL conn after already
accessing it introduced in commit 27e986289e ("scsi: iscsi: Drop suspend
calls from ep_disconnect") by just removing the function completely.

Link: https://lore.kernel.org/r/20210609192709.5094-1-michael.christie@oracle.com
Fixes: 27e986289e ("scsi: iscsi: Drop suspend calls from ep_disconnect")
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
This commit is contained in:
Mike Christie 2021-06-09 14:27:09 -05:00 committed by Martin K. Petersen
parent 2938bedd0e
commit d1f2ce7763
3 changed files with 2 additions and 23 deletions

View File

@ -72,6 +72,5 @@ void qedi_remove_sysfs_ctx_attr(struct qedi_ctx *qedi);
void qedi_clearsq(struct qedi_ctx *qedi,
struct qedi_conn *qedi_conn,
struct iscsi_task *task);
void qedi_clear_session_ctx(struct iscsi_cls_session *cls_sess);
#endif

View File

@ -1659,23 +1659,6 @@ void qedi_process_iscsi_error(struct qedi_endpoint *ep,
qedi_start_conn_recovery(qedi_conn->qedi, qedi_conn);
}
void qedi_clear_session_ctx(struct iscsi_cls_session *cls_sess)
{
struct iscsi_session *session = cls_sess->dd_data;
struct iscsi_conn *conn = session->leadconn;
struct qedi_conn *qedi_conn = conn->dd_data;
if (iscsi_is_session_online(cls_sess)) {
if (conn)
iscsi_suspend_queue(conn);
qedi_ep_disconnect(qedi_conn->iscsi_ep);
}
qedi_conn_destroy(qedi_conn->cls_conn);
qedi_session_destroy(cls_sess);
}
void qedi_process_tcp_error(struct qedi_endpoint *ep,
struct iscsi_eqe_data *data)
{

View File

@ -2417,11 +2417,9 @@ static void __qedi_remove(struct pci_dev *pdev, int mode)
int rval;
u16 retry = 10;
if (mode == QEDI_MODE_SHUTDOWN)
iscsi_host_for_each_session(qedi->shost,
qedi_clear_session_ctx);
if (mode == QEDI_MODE_NORMAL || mode == QEDI_MODE_SHUTDOWN) {
iscsi_host_remove(qedi->shost);
if (qedi->tmf_thread) {
flush_workqueue(qedi->tmf_thread);
destroy_workqueue(qedi->tmf_thread);
@ -2482,7 +2480,6 @@ static void __qedi_remove(struct pci_dev *pdev, int mode)
if (qedi->boot_kset)
iscsi_boot_destroy_kset(qedi->boot_kset);
iscsi_host_remove(qedi->shost);
iscsi_host_free(qedi->shost);
}
}