5.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: Moon Yeounsu yyyynoom@gmail.com
[ Upstream commit 12889ce926e9a9baf6b83d809ba316af539b89e2 ]
This patch synchronizes code that accesses from both user-space and IRQ contexts. The `get_stats()` function can be called from both context.
`dev->stats.tx_errors` and `dev->stats.collisions` are also updated in the `tx_errors()` function. Therefore, these fields must also be protected by synchronized.
There is no code that accessses `dev->stats.tx_errors` between the previous and updated lines, so the updating point can be moved.
Signed-off-by: Moon Yeounsu yyyynoom@gmail.com Link: https://patch.msgid.link/20250515075333.48290-1-yyyynoom@gmail.com Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/ethernet/dlink/dl2k.c | 14 +++++++++++++- drivers/net/ethernet/dlink/dl2k.h | 2 ++ 2 files changed, 15 insertions(+), 1 deletion(-)
diff --git a/drivers/net/ethernet/dlink/dl2k.c b/drivers/net/ethernet/dlink/dl2k.c index eb23157641343..8d57fb5072054 100644 --- a/drivers/net/ethernet/dlink/dl2k.c +++ b/drivers/net/ethernet/dlink/dl2k.c @@ -155,6 +155,8 @@ rio_probe1 (struct pci_dev *pdev, const struct pci_device_id *ent) np->ioaddr = ioaddr; np->chip_id = chip_idx; np->pdev = pdev; + + spin_lock_init(&np->stats_lock); spin_lock_init (&np->tx_lock); spin_lock_init (&np->rx_lock);
@@ -875,7 +877,6 @@ tx_error (struct net_device *dev, int tx_status) frame_id = (tx_status & 0xffff0000); printk (KERN_ERR "%s: Transmit error, TxStatus %4.4x, FrameId %d.\n", dev->name, tx_status, frame_id); - dev->stats.tx_errors++; /* Ttransmit Underrun */ if (tx_status & 0x10) { dev->stats.tx_fifo_errors++; @@ -912,9 +913,15 @@ tx_error (struct net_device *dev, int tx_status) rio_set_led_mode(dev); /* Let TxStartThresh stay default value */ } + + spin_lock(&np->stats_lock); /* Maximum Collisions */ if (tx_status & 0x08) dev->stats.collisions++; + + dev->stats.tx_errors++; + spin_unlock(&np->stats_lock); + /* Restart the Tx */ dw32(MACCtrl, dr16(MACCtrl) | TxEnable); } @@ -1084,7 +1091,9 @@ get_stats (struct net_device *dev) int i; #endif unsigned int stat_reg; + unsigned long flags;
+ spin_lock_irqsave(&np->stats_lock, flags); /* All statistics registers need to be acknowledged, else statistic overflow could cause problems */
@@ -1134,6 +1143,9 @@ get_stats (struct net_device *dev) dr16(TCPCheckSumErrors); dr16(UDPCheckSumErrors); dr16(IPCheckSumErrors); + + spin_unlock_irqrestore(&np->stats_lock, flags); + return &dev->stats; }
diff --git a/drivers/net/ethernet/dlink/dl2k.h b/drivers/net/ethernet/dlink/dl2k.h index 0e33e2eaae960..56aff2f0bdbfa 100644 --- a/drivers/net/ethernet/dlink/dl2k.h +++ b/drivers/net/ethernet/dlink/dl2k.h @@ -372,6 +372,8 @@ struct netdev_private { struct pci_dev *pdev; void __iomem *ioaddr; void __iomem *eeprom_addr; + // To ensure synchronization when stats are updated. + spinlock_t stats_lock; spinlock_t tx_lock; spinlock_t rx_lock; unsigned int rx_buf_sz; /* Based on MTU+slack. */