[PATCH 5.4 27/49] bnxt_en: Fix regression in workqueue cleanup logic in bnxt_remove_one().

[Greg Kroah-Hartman]

From: Vasundhara Volam <vasundhara-v.volam@xxxxxxxxxxxx>

[ Upstream commit 21d6a11e2cadfb8446265a3efff0e2aad206e15e ]

A recent patch has moved the workqueue cleanup logic before
calling unregister_netdev() in bnxt_remove_one().  This caused a
regression because the workqueue can be restarted if the device is
still open.  Workqueue cleanup must be done after unregister_netdev().
The workqueue will not restart itself after the device is closed.

Call bnxt_cancel_sp_work() after unregister_netdev() and
call bnxt_dl_fw_reporters_destroy() after that.  This fixes the
regession and the original NULL ptr dereference issue.

Fixes: b16939b59cc0 ("bnxt_en: Fix NULL ptr dereference crash in bnxt_fw_reset_task()")
Signed-off-by: Vasundhara Volam <vasundhara-v.volam@xxxxxxxxxxxx>
Signed-off-by: Michael Chan <michael.chan@xxxxxxxxxxxx>
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/net/ethernet/broadcom/bnxt/bnxt.c |    5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
@@ -11396,13 +11396,14 @@ static void bnxt_remove_one(struct pci_d
 	if (BNXT_PF(bp))
 		bnxt_sriov_disable(bp);
 
+	pci_disable_pcie_error_reporting(pdev);
+	unregister_netdev(dev);
 	clear_bit(BNXT_STATE_IN_FW_RESET, &bp->state);
+	/* Flush any pending tasks */
 	bnxt_cancel_sp_work(bp);
 	bp->sp_event = 0;
 
 	bnxt_dl_fw_reporters_destroy(bp, true);
-	pci_disable_pcie_error_reporting(pdev);
-	unregister_netdev(dev);
 	bnxt_dl_unregister(bp);
 	bnxt_shutdown_tc(bp);