bnx2x: new flag for track HW resource allocation

While injecting PCIe errors to the upstream PCIe switch of
a BCM57810 NIC, system hangs/crashes were observed.

After several calls to bnx2x_tx_timout() complete,
bnx2x_nic_unload() is called to free up HW resources
and bnx2x_napi_disable() is called to release NAPI objects.
Later, when the EEH driver calls bnx2x_io_slot_reset() to
complete the recovery process, bnx2x attempts to disable
NAPI again by calling bnx2x_napi_disable() and freeing
resources which have already been freed, resulting in a
hang or crash.

Introduce a new flag to track the HW resource and NAPI
allocation state, refactor duplicated code into a single
function, check page pool allocation status before freeing,
and reduces debug output when a TX timeout event occurs.

Reviewed-by: Manish Chopra <[email protected]>
Tested-by: Abdul Haleem <[email protected]>
Tested-by: David Christensen <[email protected]>
Reviewed-by: Simon Horman <[email protected]>
Tested-by: Venkata Sai Duggi <[email protected]>
Signed-off-by: Thinh Tran <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>

Author: ThinhTrTran

drivers/net/ethernet/broadcom/bnx2x/bnx2x.h

@@ -1508,6 +1508,8 @@ struct bnx2x {
 	bool			cnic_loaded;
 	struct cnic_eth_dev	*(*cnic_probe)(struct net_device *);
 
+	bool                    nic_stopped;
+
 	/* Flag that indicates that we can start looking for FCoE L2 queue
 	 * completions in the default status block.
 	 */

drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c

@@ -2715,6 +2715,7 @@ int bnx2x_nic_load(struct bnx2x *bp, int load_mode)
 	bnx2x_add_all_napi(bp);
 	DP(NETIF_MSG_IFUP, "napi added\n");
 	bnx2x_napi_enable(bp);
+	bp->nic_stopped = false;
 
 	if (IS_PF(bp)) {
 		/* set pf load just before approaching the MCP */
@@ -2960,6 +2961,7 @@ int bnx2x_nic_load(struct bnx2x *bp, int load_mode)
 load_error1:
 	bnx2x_napi_disable(bp);
 	bnx2x_del_all_napi(bp);
+	bp->nic_stopped = true;
 
 	/* clear pf_load status, as it was already set */
 	if (IS_PF(bp))
@@ -3095,14 +3097,17 @@ int bnx2x_nic_unload(struct bnx2x *bp, int unload_mode, bool keep_link)
 		if (!CHIP_IS_E1x(bp))
 			bnx2x_pf_disable(bp);
 
-		/* Disable HW interrupts, NAPI */
-		bnx2x_netif_stop(bp, 1);
-		/* Delete all NAPI objects */
-		bnx2x_del_all_napi(bp);
-		if (CNIC_LOADED(bp))
-			bnx2x_del_all_napi_cnic(bp);
-		/* Release IRQs */
-		bnx2x_free_irq(bp);
+		if (!bp->nic_stopped) {
+			/* Disable HW interrupts, NAPI */
+			bnx2x_netif_stop(bp, 1);
+			/* Delete all NAPI objects */
+			bnx2x_del_all_napi(bp);
+			if (CNIC_LOADED(bp))
+				bnx2x_del_all_napi_cnic(bp);
+			/* Release IRQs */
+			bnx2x_free_irq(bp);
+			bp->nic_stopped = true;
+		}
 
 		/* Report UNLOAD_DONE to MCP */
 		bnx2x_send_unload_done(bp, false);

drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.c

@@ -9474,15 +9474,18 @@ void bnx2x_chip_cleanup(struct bnx2x *bp, int unload_mode, bool keep_link)
 		}
 	}
 
-	/* Disable HW interrupts, NAPI */
-	bnx2x_netif_stop(bp, 1);
-	/* Delete all NAPI objects */
-	bnx2x_del_all_napi(bp);
-	if (CNIC_LOADED(bp))
-		bnx2x_del_all_napi_cnic(bp);
+	if (!bp->nic_stopped) {
+		/* Disable HW interrupts, NAPI */
+		bnx2x_netif_stop(bp, 1);
+		/* Delete all NAPI objects */
+		bnx2x_del_all_napi(bp);
+		if (CNIC_LOADED(bp))
+			bnx2x_del_all_napi_cnic(bp);
 
-	/* Release IRQs */
-	bnx2x_free_irq(bp);
+		/* Release IRQs */
+		bnx2x_free_irq(bp);
+		bp->nic_stopped = true;
+	}
 
 	/* Reset the chip, unless PCI function is offline. If we reach this
 	 * point following a PCI error handling, it means device is really
@@ -14238,13 +14241,16 @@ static pci_ers_result_t bnx2x_io_slot_reset(struct pci_dev *pdev)
 		}
 		bnx2x_drain_tx_queues(bp);
 		bnx2x_send_unload_req(bp, UNLOAD_RECOVERY);
-		bnx2x_netif_stop(bp, 1);
-		bnx2x_del_all_napi(bp);
+		if (!bp->nic_stopped) {
+			bnx2x_netif_stop(bp, 1);
+			bnx2x_del_all_napi(bp);
 
-		if (CNIC_LOADED(bp))
-			bnx2x_del_all_napi_cnic(bp);
+			if (CNIC_LOADED(bp))
+				bnx2x_del_all_napi_cnic(bp);
 
-		bnx2x_free_irq(bp);
+			bnx2x_free_irq(bp);
+			bp->nic_stopped = true;
+		}
 
 		/* Report UNLOAD_DONE to MCP */
 		bnx2x_send_unload_done(bp, true);

drivers/net/ethernet/broadcom/bnx2x/bnx2x_vfpf.c

@@ -529,13 +529,16 @@ void bnx2x_vfpf_close_vf(struct bnx2x *bp)
 	bnx2x_vfpf_finalize(bp, &req->first_tlv);
 
 free_irq:
-	/* Disable HW interrupts, NAPI */
-	bnx2x_netif_stop(bp, 0);
-	/* Delete all NAPI objects */
-	bnx2x_del_all_napi(bp);
-
-	/* Release IRQs */
-	bnx2x_free_irq(bp);
+	if (!bp->nic_stopped) {
+		/* Disable HW interrupts, NAPI */
+		bnx2x_netif_stop(bp, 0);
+		/* Delete all NAPI objects */
+		bnx2x_del_all_napi(bp);
+
+		/* Release IRQs */
+		bnx2x_free_irq(bp);
+		bp->nic_stopped = true;
+	}
 }
 
 static void bnx2x_leading_vfq_init(struct bnx2x *bp, struct bnx2x_virtf *vf,