4.19-stable review patch. If anyone has any objections, please let me know.
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[ Upstream commit 5f2b8b62786853341a20d4cd4948f9cbca3db002 ]
Setting up and tearing down debugfs is current unbalanced, as seen by this error during resume from suspend:
[ 752.134067] dwc-eth-dwmac 2490000.ethernet eth0: ERROR failed to create debugfs directory [ 752.134347] dwc-eth-dwmac 2490000.ethernet eth0: stmmac_hw_setup: failed debugFS registration
The imbalance happens because the driver creates the debugfs hierarchy when the device is opened and tears it down when the device is closed. There's little gain in that, and it could be argued that it is even surprising because it's not usually done for other devices. Fix the imbalance by moving the debugfs creation and teardown to the driver's ->probe() and ->remove() implementations instead.
Note that the ring descriptors cannot be read while the interface is down, so make sure to return an empty file when the descriptors_status debugfs file is read.
Signed-off-by: Thierry Reding treding@nvidia.com Acked-by: Jose Abreu joabreu@synopsys.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- .../net/ethernet/stmicro/stmmac/stmmac_main.c | 23 +++++++++++-------- 1 file changed, 13 insertions(+), 10 deletions(-)
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c index 75896d6ba6e2..99ea5c4ce29c 100644 --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c @@ -2547,12 +2547,6 @@ static int stmmac_hw_setup(struct net_device *dev, bool init_ptp) netdev_warn(priv->dev, "PTP init failed\n"); }
-#ifdef CONFIG_DEBUG_FS - ret = stmmac_init_fs(dev); - if (ret < 0) - netdev_warn(priv->dev, "%s: failed debugFS registration\n", - __func__); -#endif priv->tx_lpi_timer = STMMAC_DEFAULT_TWT_LS;
if (priv->use_riwt) { @@ -2753,10 +2747,6 @@ static int stmmac_release(struct net_device *dev)
netif_carrier_off(dev);
-#ifdef CONFIG_DEBUG_FS - stmmac_exit_fs(dev); -#endif - stmmac_release_ptp(priv);
return 0; @@ -3896,6 +3886,9 @@ static int stmmac_sysfs_ring_read(struct seq_file *seq, void *v) u32 tx_count = priv->plat->tx_queues_to_use; u32 queue;
+ if ((dev->flags & IFF_UP) == 0) + return 0; + for (queue = 0; queue < rx_count; queue++) { struct stmmac_rx_queue *rx_q = &priv->rx_queue[queue];
@@ -4394,6 +4387,13 @@ int stmmac_dvr_probe(struct device *device, goto error_netdev_register; }
+#ifdef CONFIG_DEBUG_FS + ret = stmmac_init_fs(ndev); + if (ret < 0) + netdev_warn(priv->dev, "%s: failed debugFS registration\n", + __func__); +#endif + return ret;
error_netdev_register: @@ -4429,6 +4429,9 @@ int stmmac_dvr_remove(struct device *dev)
netdev_info(priv->dev, "%s: removing driver", __func__);
+#ifdef CONFIG_DEBUG_FS + stmmac_exit_fs(ndev); +#endif stmmac_stop_all_dma(priv);
stmmac_mac_set(priv, priv->ioaddr, false);