amd-xgbe: fix sleep while atomic on suspend/resume

[ Upstream commit e2f27363aa6d983504c6836dd0975535e2e9dba0 ]

The xgbe_powerdown() and xgbe_powerup() functions use spinlocks
(spin_lock_irqsave) while calling functions that may sleep:
- napi_disable() can sleep waiting for NAPI polling to complete
- flush_workqueue() can sleep waiting for pending work items

This causes a "BUG: scheduling while atomic" error during suspend/resume
cycles on systems using the AMD XGBE Ethernet controller.

The spinlock protection in these functions is unnecessary as these
functions are called from suspend/resume paths which are already serialized
by the PM core

Fix this by removing the spinlock. Since only code that takes this lock
is xgbe_powerdown() and xgbe_powerup(), remove it completely.

Fixes: c5aa9e3b8156 ("amd-xgbe: Initial AMD 10GbE platform driver")
Signed-off-by: Raju Rangoju <Raju.Rangoju@amd.com>
Link: https://patch.msgid.link/20260302042124.1386445-1-Raju.Rangoju@amd.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

3 files changed, 0 insertions, 14 deletions

diff --git a/drivers/net/ethernet/amd/xgbe/xgbe-drv.c b/drivers/net/ethernet/amd/xgbe/xgbe-drv.c
index e6a249236022..c6fcddbff3f5 100644
--- a/drivers/net/ethernet/amd/xgbe/xgbe-drv.c
+++ b/drivers/net/ethernet/amd/xgbe/xgbe-drv.c
@@ -1181,7 +1181,6 @@ int xgbe_powerdown(struct net_device *netdev, unsigned int caller)
 {
 	struct xgbe_prv_data *pdata = netdev_priv(netdev);
 	struct xgbe_hw_if *hw_if = &pdata->hw_if;
-	unsigned long flags;
 
 	DBGPR("-->xgbe_powerdown\n");
 
@@ -1192,8 +1191,6 @@ int xgbe_powerdown(struct net_device *netdev, unsigned int caller)
 		return -EINVAL;
 	}
 
-	spin_lock_irqsave(&pdata->lock, flags);
-
 	if (caller == XGMAC_DRIVER_CONTEXT)
 		netif_device_detach(netdev);
 
@@ -1209,8 +1206,6 @@ int xgbe_powerdown(struct net_device *netdev, unsigned int caller)
 
 	pdata->power_down = 1;
 
-	spin_unlock_irqrestore(&pdata->lock, flags);
-
 	DBGPR("<--xgbe_powerdown\n");
 
 	return 0;
@@ -1220,7 +1215,6 @@ int xgbe_powerup(struct net_device *netdev, unsigned int caller)
 {
 	struct xgbe_prv_data *pdata = netdev_priv(netdev);
 	struct xgbe_hw_if *hw_if = &pdata->hw_if;
-	unsigned long flags;
 
 	DBGPR("-->xgbe_powerup\n");
 
@@ -1231,8 +1225,6 @@ int xgbe_powerup(struct net_device *netdev, unsigned int caller)
 		return -EINVAL;
 	}
 
-	spin_lock_irqsave(&pdata->lock, flags);
-
 	pdata->power_down = 0;
 
 	xgbe_napi_enable(pdata, 0);
@@ -1247,8 +1239,6 @@ int xgbe_powerup(struct net_device *netdev, unsigned int caller)
 
 	xgbe_start_timers(pdata);
 
-	spin_unlock_irqrestore(&pdata->lock, flags);
-
 	DBGPR("<--xgbe_powerup\n");
 
 	return 0;
diff --git a/drivers/net/ethernet/amd/xgbe/xgbe-main.c b/drivers/net/ethernet/amd/xgbe/xgbe-main.c
index 0e8698928e4d..6e8fafb2acba 100644
--- a/drivers/net/ethernet/amd/xgbe/xgbe-main.c
+++ b/drivers/net/ethernet/amd/xgbe/xgbe-main.c
@@ -185,7 +185,6 @@ struct xgbe_prv_data *xgbe_alloc_pdata(struct device *dev)
 	pdata->netdev = netdev;
 	pdata->dev = dev;
 
-	spin_lock_init(&pdata->lock);
 	spin_lock_init(&pdata->xpcs_lock);
 	mutex_init(&pdata->rss_mutex);
 	spin_lock_init(&pdata->tstamp_lock);
diff --git a/drivers/net/ethernet/amd/xgbe/xgbe.h b/drivers/net/ethernet/amd/xgbe/xgbe.h
index 7526a0906b39..c98461252053 100644
--- a/drivers/net/ethernet/amd/xgbe/xgbe.h
+++ b/drivers/net/ethernet/amd/xgbe/xgbe.h
@@ -1083,9 +1083,6 @@ struct xgbe_prv_data {
 	unsigned int pp3;
 	unsigned int pp4;
 
-	/* Overall device lock */
-	spinlock_t lock;
-
 	/* XPCS indirect addressing lock */
 	spinlock_t xpcs_lock;
 	unsigned int xpcs_window_def_reg;