-----Original Message-----
From: Ivan Vecera <ivecera@redhat.com>
Sent: Tuesday, August 30, 2022 10:16 AM
Subject: [PATCH net v2] iavf: Detach device during reset task

iavf_reset_task() takes crit_lock at the beginning and holds it during whole call.
The function subsequently calls
iavf_init_interrupt_scheme() that grabs RTNL. Problem occurs when userspace
initiates during the reset task any ndo callback that runs under RTNL like
iavf_open() because some of that functions tries to take crit_lock. This leads to
classic A-B B-A deadlock scenario.

To resolve this situation the device should be detached in
iavf_reset_task() prior taking crit_lock to avoid subsequent ndos running under
RTNL and reattach the device at the end.

Fixes: 62fe2a865e6d ("i40evf: add missing rtnl_lock() around
i40evf_set_interrupt_capability")
Cc: Jacob Keller <jacob.e.keller@intel.com>
Cc: Patryk Piotrowski <redacted>
Cc: SlawomirX Laba <redacted>
Tested-by: Vitaly Grinberg <redacted>
Signed-off-by: Ivan Vecera <ivecera@redhat.com>

@@ -2884,7 +2889,7 @@ static void iavf_reset_task(struct work_struct *work)
 		if (adapter->state != __IAVF_REMOVE)
 			queue_work(iavf_wq, &adapter->reset_task);

-		return;
+		goto reset_finish;
 	}

 	while (!mutex_trylock(&adapter->client_lock))