Hi,
On 1/23/2024 15:25, Dan Carpenter wrote:
> Hello Lendacky, Thomas,
>
> The patch c5aa9e3b8156: "amd-xgbe: Initial AMD 10GbE platform driver"
> from Jun 5, 2014 (linux-next), leads to the following Smatch static
> checker warning:
>
> drivers/net/ethernet/amd/xgbe/xgbe-drv.c:1209 xgbe_powerdown()
> warn: sleeping in atomic context
>
> drivers/net/ethernet/amd/xgbe/xgbe-drv.c
> 1181 int xgbe_powerdown(struct net_device *netdev, unsigned int caller)
> 1182 {
> 1183 struct xgbe_prv_data *pdata = netdev_priv(netdev);
> 1184 struct xgbe_hw_if *hw_if = &pdata->hw_if;
> 1185 unsigned long flags;
> 1186
> 1187 DBGPR("-->xgbe_powerdown\n");
> 1188
> 1189 if (!netif_running(netdev) ||
> 1190 (caller == XGMAC_IOCTL_CONTEXT && pdata->power_down)) {
> 1191 netdev_alert(netdev, "Device is already powered down\n");
> 1192 DBGPR("<--xgbe_powerdown\n");
> 1193 return -EINVAL;
> 1194 }
> 1195
> 1196 spin_lock_irqsave(&pdata->lock, flags);
> ^^^^^^^^^^^^^^^^^
> Preempt disabled.
>
> 1197
> 1198 if (caller == XGMAC_DRIVER_CONTEXT)
> 1199 netif_device_detach(netdev);
> 1200
> 1201 netif_tx_stop_all_queues(netdev);
> 1202
> 1203 xgbe_stop_timers(pdata);
> 1204 flush_workqueue(pdata->dev_workqueue);
> 1205
> 1206 hw_if->powerdown_tx(pdata);
> 1207 hw_if->powerdown_rx(pdata);
> 1208
> --> 1209 xgbe_napi_disable(pdata, 0);
>
> This warning is correct, but it only showed up because I messed up my
> devel version of Smatch last night to make it assume that we almost
> always enter into loops at least one time.
>
> The napi_disable() function cannot be called while holding a spinlock.
>
> You would need to enable DEBUG_ATOMIC_SLEEP to see these warnings at
> runtime.
Thanks for the bug report Dan. Shall send a patch to address this.
Thanks,
Shyam
>
> 1210
> 1211 pdata->power_down = 1;
> 1212
> 1213 spin_unlock_irqrestore(&pdata->lock, flags);
> 1214
> 1215 DBGPR("<--xgbe_powerdown\n");
> 1216
> 1217 return 0;
> 1218 }
>
> regards,
> dan carpenter
