net: cadence: macb: Synchronize stats calculations

[ Upstream commit fa52f15c745ce55261b92873676f64f7348cfe82 ]

Stats calculations involve a RMW to add the stat update to the existing
value. This is currently not protected by any synchronization mechanism,
so data races are possible. Add a spinlock to protect the update. The
reader side could be protected using u64_stats, but we would still need
a spinlock for the update side anyway. And we always do an update
immediately before reading the stats anyway.

Fixes: 89e5785fc8 ("[PATCH] Atmel MACB ethernet driver")
Signed-off-by: Sean Anderson <sean.anderson@linux.dev>
Link: https://patch.msgid.link/20250220162950.95941-1-sean.anderson@linux.dev
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Sean Anderson
2025-02-20 11:29:50 -05:00
committed by Greg Kroah-Hartman
parent 5b8dea8d16
commit 90ed67b03a
2 changed files with 12 additions and 2 deletions

View File

@@ -1271,6 +1271,8 @@ struct macb {
struct clk *rx_clk;
struct clk *tsu_clk;
struct net_device *dev;
/* Protects hw_stats and ethtool_stats */
spinlock_t stats_lock;
union {
struct macb_stats macb;
struct gem_stats gem;

View File

@@ -1936,10 +1936,12 @@ static irqreturn_t macb_interrupt(int irq, void *dev_id)
if (status & MACB_BIT(ISR_ROVR)) {
/* We missed at least one packet */
spin_lock(&bp->stats_lock);
if (macb_is_gem(bp))
bp->hw_stats.gem.rx_overruns++;
else
bp->hw_stats.macb.rx_overruns++;
spin_unlock(&bp->stats_lock);
if (bp->caps & MACB_CAPS_ISR_CLEAR_ON_WRITE)
queue_writel(queue, ISR, MACB_BIT(ISR_ROVR));
@@ -2999,6 +3001,7 @@ static struct net_device_stats *gem_get_stats(struct macb *bp)
if (!netif_running(bp->dev))
return nstat;
spin_lock_irq(&bp->stats_lock);
gem_update_stats(bp);
nstat->rx_errors = (hwstat->rx_frame_check_sequence_errors +
@@ -3028,6 +3031,7 @@ static struct net_device_stats *gem_get_stats(struct macb *bp)
nstat->tx_aborted_errors = hwstat->tx_excessive_collisions;
nstat->tx_carrier_errors = hwstat->tx_carrier_sense_errors;
nstat->tx_fifo_errors = hwstat->tx_underrun;
spin_unlock_irq(&bp->stats_lock);
return nstat;
}
@@ -3035,12 +3039,13 @@ static struct net_device_stats *gem_get_stats(struct macb *bp)
static void gem_get_ethtool_stats(struct net_device *dev,
struct ethtool_stats *stats, u64 *data)
{
struct macb *bp;
struct macb *bp = netdev_priv(dev);
bp = netdev_priv(dev);
spin_lock_irq(&bp->stats_lock);
gem_update_stats(bp);
memcpy(data, &bp->ethtool_stats, sizeof(u64)
* (GEM_STATS_LEN + QUEUE_STATS_LEN * MACB_MAX_QUEUES));
spin_unlock_irq(&bp->stats_lock);
}
static int gem_get_sset_count(struct net_device *dev, int sset)
@@ -3090,6 +3095,7 @@ static struct net_device_stats *macb_get_stats(struct net_device *dev)
return gem_get_stats(bp);
/* read stats from hardware */
spin_lock_irq(&bp->stats_lock);
macb_update_stats(bp);
/* Convert HW stats into netdevice stats */
@@ -3123,6 +3129,7 @@ static struct net_device_stats *macb_get_stats(struct net_device *dev)
nstat->tx_carrier_errors = hwstat->tx_carrier_errors;
nstat->tx_fifo_errors = hwstat->tx_underruns;
/* Don't know about heartbeat or window errors... */
spin_unlock_irq(&bp->stats_lock);
return nstat;
}
@@ -4949,6 +4956,7 @@ static int macb_probe(struct platform_device *pdev)
bp->usrio = macb_config->usrio;
spin_lock_init(&bp->lock);
spin_lock_init(&bp->stats_lock);
/* setup capabilities */
macb_configure_caps(bp, macb_config);