From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3C7071C6FFE; Wed, 5 Mar 2025 17:56:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741197370; cv=none; b=IodqgauR7t0zyoFn6j+Jc2gN/iBak3v3lUBY/8wjNDIE6HcmyYxDqoYzyHGOeJHpLbUD7kqIn/jp/btSW9A2efA+DHsUWWmRxQHY6Tex80p8Hsl/0ezFiud/xLfUQCkGPYfxzjH1xdNscaY1yADHnh2vNjWP1kEz5SFnaHiXhD0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741197370; c=relaxed/simple; bh=SNVP032vHmFXS/WmVJt6GLGbV5gelbF7iB2ApA19E+w=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=iKAHLfjXzZhKmbNmKP1iAbmfxCNA5UaA2eNybgsLKy6UX/Etb+N4TbLEZ2bS0spJ+GOqSdhPYeeY3WZD8qUyjzb454sxJ+mz8+DujB0PNBBlyPi6TMfgtrqc7FYZIi9upOjauU/HDAjaPfS8BrNqgL1LvEj03UcoDhPMqqeOtBg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=WiSI5HV5; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="WiSI5HV5" Received: by smtp.kernel.org (Postfix) with ESMTPSA id BC0B1C4CED1; Wed, 5 Mar 2025 17:56:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1741197370; bh=SNVP032vHmFXS/WmVJt6GLGbV5gelbF7iB2ApA19E+w=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=WiSI5HV57bmT5yIVHKOQ6l41d94Y+ZoqEMUKGlK32DYyB4Bdy1Il5e66YyyfHMUkI XiYKa8BLpHC8FX45nGzBIhJqsx/y2JnOuAju9cb7CiJ+ymqnsoUGUWbhw6RSe9Lli8 EebxBAndl1gylfnVOJexcdED8iwU4g1D+fggmO40= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Sean Anderson , Jakub Kicinski , Sasha Levin Subject: [PATCH 6.1 131/176] net: cadence: macb: Synchronize stats calculations Date: Wed, 5 Mar 2025 18:48:20 +0100 Message-ID: <20250305174510.707639121@linuxfoundation.org> X-Mailer: git-send-email 2.48.1 In-Reply-To: <20250305174505.437358097@linuxfoundation.org> References: <20250305174505.437358097@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Sean Anderson [ 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: 89e5785fc8a6 ("[PATCH] Atmel MACB ethernet driver") Signed-off-by: Sean Anderson Link: https://patch.msgid.link/20250220162950.95941-1-sean.anderson@linux.dev Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- drivers/net/ethernet/cadence/macb.h | 2 ++ drivers/net/ethernet/cadence/macb_main.c | 12 ++++++++++-- 2 files changed, 12 insertions(+), 2 deletions(-) diff --git a/drivers/net/ethernet/cadence/macb.h b/drivers/net/ethernet/cadence/macb.h index 1aa578c1ca4ad..8d66de71ea604 100644 --- a/drivers/net/ethernet/cadence/macb.h +++ b/drivers/net/ethernet/cadence/macb.h @@ -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; diff --git a/drivers/net/ethernet/cadence/macb_main.c b/drivers/net/ethernet/cadence/macb_main.c index d44d53d697620..fc3342944dbcc 100644 --- a/drivers/net/ethernet/cadence/macb_main.c +++ b/drivers/net/ethernet/cadence/macb_main.c @@ -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); -- 2.39.5