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

From: Greg Kroah-Hartman
Date: Sat Oct 31 2020 - 07:36:49 EST


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);