[PATCH 4.9 003/151] sfc: Only cancel the PPS workqueue if it exists

[Greg Kroah-Hartman]

From: Martin Habets <mhabets@xxxxxxxxxxxxxx>

[ Upstream commit 723eb53690041740a13ac78efeaf6804f5d684c9 ]

The workqueue only exists for the primary PF. For other functions
we hit a WARN_ON in kernel/workqueue.c.

Fixes: 7c236c43b838 ("sfc: Add support for IEEE-1588 PTP")
Signed-off-by: Martin Habets <mhabets@xxxxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/net/ethernet/sfc/ptp.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

--- a/drivers/net/ethernet/sfc/ptp.c
+++ b/drivers/net/ethernet/sfc/ptp.c
@@ -1320,7 +1320,8 @@ void efx_ptp_remove(struct efx_nic *efx)
 	(void)efx_ptp_disable(efx);
 
 	cancel_work_sync(&efx->ptp_data->work);
-	cancel_work_sync(&efx->ptp_data->pps_work);
+	if (efx->ptp_data->pps_workwq)
+		cancel_work_sync(&efx->ptp_data->pps_work);
 
 	skb_queue_purge(&efx->ptp_data->rxq);
 	skb_queue_purge(&efx->ptp_data->txq);