ibmvnic: Free any outstanding tx skbs during scrq reset

[ Upstream commit 49bbeb5 ]

There are 2 types of outstanding tx skb's:
Type 1: Packets that are sitting in the drivers ind_buff that are
waiting to be batch sent to the NIC. During a device reset, these are
freed with a call to ibmvnic_tx_scrq_clean_buffer()
Type 2: Packets that have been sent to the NIC and are awaiting a TX
completion IRQ. These are free'd during a reset with a call to
clean_tx_pools()

During any reset which requires us to free the tx irq, ensure that the
Type 2 skb references are freed. Since the irq is released, it is
impossible for the NIC to inform of any completions.

Furthermore, later in the reset process is a call to init_tx_pools()
which marks every entry in the tx pool as free (ie not outstanding).
So if the driver is to make a call to init_tx_pools(), it must first
be sure that the tx pool is empty of skb references.

This issue was discovered by observing the following in the logs during
EEH testing:
	TX free map points to untracked skb (tso_pool 0 idx=4)
	TX free map points to untracked skb (tso_pool 0 idx=5)
	TX free map points to untracked skb (tso_pool 1 idx=36)

Fixes: 65d6470 ("ibmvnic: clean pending indirect buffs during reset")
Signed-off-by: Nick Child <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>

drivers/net/ethernet/ibm/ibmvnic.c

@@ -4057,6 +4057,12 @@ static void release_sub_crqs(struct ibmvnic_adapter *adapter, bool do_h_free)
 		adapter->num_active_tx_scrqs = 0;
 	}
 
+	/* Clean any remaining outstanding SKBs
+	 * we freed the irq so we won't be hearing
+	 * from them
+	 */
+	clean_tx_pools(adapter);
+
 	if (adapter->rx_scrq) {
 		for (i = 0; i < adapter->num_active_rx_scrqs; i++) {
 			if (!adapter->rx_scrq[i])