[PATCH net-next v2 09/14] idpf: make mbx_task queueing and cancelling more consistent

[Tony Nguyen <anthony.l.nguyen@intel.com>]

From: Larysa Zaremba <larysa.zaremba@intel.com>

As a consequence of refactoring idpf code to use libeth APIs,
idpf_vc_xn_shutdown was merged with and replaced by idpf_deinit_dflt_mbx.
This does not affect the Tx path, as it checked for a presence of an xn
manager anyway. Rx processing is handled by the mbx_task that is not always
cancelled before calling the new consolidated mailbox deinit function.
Moreover, in the reset path idpf_intr_rel() reschedules it after the deinit
is done. This leads to mbx_task referencing the freed mailbox and causing
KASAN warnings.

To remedy this, in the init path, do the first queueing of mbx_task in
idpf_init_dflt_mbx(), in deinit and reset, always cancel the task in
idpf_deinit_dflt_mbx() and in every flow first call idpf_mb_intr_rel_irq().

Reviewed-by: Emil Tantilov <emil.s.tantilov@intel.com>
Reviewed-by: Michal Kubiak <michal.kubiak@intel.com>
Signed-off-by: Larysa Zaremba <larysa.zaremba@intel.com>
Tested-by: Samuel Salin <Samuel.salin@intel.com>
Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
---
 drivers/net/ethernet/intel/idpf/idpf.h          | 1 +
 drivers/net/ethernet/intel/idpf/idpf_lib.c      | 9 ++++-----
 drivers/net/ethernet/intel/idpf/idpf_virtchnl.c | 6 +++++-
 3 files changed, 10 insertions(+), 6 deletions(-)

diff --git a/drivers/net/ethernet/intel/idpf/idpf.h b/drivers/net/ethernet/intel/idpf/idpf.h
index 679539a1b947..1d0e32e47e87 100644
--- a/drivers/net/ethernet/intel/idpf/idpf.h
+++ b/drivers/net/ethernet/intel/idpf/idpf.h
@@ -984,6 +984,7 @@ void idpf_vc_event_task(struct work_struct *work);
 void idpf_dev_ops_init(struct idpf_adapter *adapter);
 void idpf_vf_dev_ops_init(struct idpf_adapter *adapter);
 int idpf_intr_req(struct idpf_adapter *adapter);
+void idpf_mb_intr_rel_irq(struct idpf_adapter *adapter);
 void idpf_intr_rel(struct idpf_adapter *adapter);
 u16 idpf_get_max_tx_hdr_size(struct idpf_adapter *adapter);
 int idpf_initiate_soft_reset(struct idpf_vport *vport,
diff --git a/drivers/net/ethernet/intel/idpf/idpf_lib.c b/drivers/net/ethernet/intel/idpf/idpf_lib.c
index 0d131bf0993e..7988836fbae0 100644
--- a/drivers/net/ethernet/intel/idpf/idpf_lib.c
+++ b/drivers/net/ethernet/intel/idpf/idpf_lib.c
@@ -68,9 +68,11 @@ static void idpf_deinit_vector_stack(struct idpf_adapter *adapter)
  * This will also disable interrupt mode and queue up mailbox task. Mailbox
  * task will reschedule itself if not in interrupt mode.
  */
-static void idpf_mb_intr_rel_irq(struct idpf_adapter *adapter)
+void idpf_mb_intr_rel_irq(struct idpf_adapter *adapter)
 {
-	clear_bit(IDPF_MB_INTR_MODE, adapter->flags);
+	if (!test_and_clear_bit(IDPF_MB_INTR_MODE, adapter->flags))
+		return;
+
 	kfree(free_irq(adapter->msix_entries[0].vector, adapter));
 	queue_delayed_work(adapter->mbx_wq, &adapter->mbx_task, 0);
 }
@@ -1938,14 +1940,11 @@ static void idpf_init_hard_reset(struct idpf_adapter *adapter)
 		goto unlock_mutex;
 	}
 
-	queue_delayed_work(adapter->mbx_wq, &adapter->mbx_task, 0);
-
 	/* Initialize the state machine, also allocate memory and request
 	 * resources
 	 */
 	err = idpf_vc_core_init(adapter);
 	if (err) {
-		cancel_delayed_work_sync(&adapter->mbx_task);
 		idpf_deinit_dflt_mbx(adapter);
 		goto unlock_mutex;
 	}
diff --git a/drivers/net/ethernet/intel/idpf/idpf_virtchnl.c b/drivers/net/ethernet/intel/idpf/idpf_virtchnl.c
index 47eb8b521755..412159bb6259 100644
--- a/drivers/net/ethernet/intel/idpf/idpf_virtchnl.c
+++ b/drivers/net/ethernet/intel/idpf/idpf_virtchnl.c
@@ -2974,6 +2974,8 @@ int idpf_init_dflt_mbx(struct idpf_adapter *adapter)
 	adapter->xnm = params.xnm;
 	adapter->state = __IDPF_VER_CHECK;
 
+	queue_delayed_work(adapter->mbx_wq, &adapter->mbx_task, 0);
+
 	return 0;
 }
 
@@ -2983,6 +2985,9 @@ int idpf_init_dflt_mbx(struct idpf_adapter *adapter)
  */
 void idpf_deinit_dflt_mbx(struct idpf_adapter *adapter)
 {
+	idpf_mb_intr_rel_irq(adapter);
+	cancel_delayed_work_sync(&adapter->mbx_task);
+
 	if (adapter->arq && adapter->asq) {
 		idpf_mb_clean(adapter, adapter->asq, true);
 		libie_ctlq_xn_deinit(adapter->xnm, &adapter->ctlq_ctx);
@@ -3237,7 +3242,6 @@ void idpf_vc_core_deinit(struct idpf_adapter *adapter)
 		idpf_deinit_dflt_mbx(adapter);
 
 	cancel_delayed_work_sync(&adapter->serv_task);
-	cancel_delayed_work_sync(&adapter->mbx_task);
 
 	idpf_vport_params_buf_rel(adapter);
 
-- 
2.47.1