From e1406330d70e56dd44fa6fbafc86e77e5c80c122 Mon Sep 17 00:00:00 2001 From: Runyu Xiao Date: Tue, 8 Sep 2026 18:39:24 +0800 Subject: [PATCH] net: macb: initialize PTP state before registering clock MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit gem_ptp_init() registers the PTP clock before initializing bp->tsu_clk_lock and the TSU hardware. Since ptp_clock_register() publishes the PTP character device, userspace may invoke PTP callbacks before the lock and hardware are ready. In addition, gem_ptp_init() is called from both the interface open and resume paths. Reinitializing tsu_clk_lock there can reset the lock while timestamp processing is using it. This race is theoretical and has not been observed in practice. Initialize tsu_clk_lock once during probe and initialize the TSU before registering the PTP clock. Fixes: ab91f0a9b5f4 ("net: macb: Add hardware PTP support") Cc: stable@vger.kernel.org Link: https://lore.kernel.org/netdev/20260904030439.3994047-1-runyu.xiao@seu.edu.cn/ Reviewed-by: Théo Lebrun Reviewed-by: Vadim Fedorenko Signed-off-by: Runyu Xiao Link: https://patch.msgid.link/20260908103924.607033-1-runyu.xiao@seu.edu.cn Signed-off-by: Jakub Kicinski --- drivers/net/ethernet/cadence/macb_main.c | 1 + drivers/net/ethernet/cadence/macb_ptp.c | 5 +---- 2 files changed, 2 insertions(+), 4 deletions(-) diff --git a/drivers/net/ethernet/cadence/macb_main.c b/drivers/net/ethernet/cadence/macb_main.c index 77dec2d6e3fb..4cb5d7088d43 100644 --- a/drivers/net/ethernet/cadence/macb_main.c +++ b/drivers/net/ethernet/cadence/macb_main.c @@ -5883,6 +5883,7 @@ static int macb_probe(struct platform_device *pdev) } spin_lock_init(&bp->lock); spin_lock_init(&bp->stats_lock); + spin_lock_init(&bp->tsu_clk_lock); /* setup capabilities */ macb_configure_caps(bp, macb_config); diff --git a/drivers/net/ethernet/cadence/macb_ptp.c b/drivers/net/ethernet/cadence/macb_ptp.c index e5195d7dac1d..6d9166389988 100644 --- a/drivers/net/ethernet/cadence/macb_ptp.c +++ b/drivers/net/ethernet/cadence/macb_ptp.c @@ -334,6 +334,7 @@ void gem_ptp_init(struct net_device *netdev) bp->tsu_rate = bp->ptp_info->get_tsu_rate(bp); bp->ptp_clock_info.max_adj = bp->ptp_info->get_ptp_max_adj(); gem_ptp_init_timer(bp); + gem_ptp_init_tsu(bp); bp->ptp_clock = ptp_clock_register(&bp->ptp_clock_info, &netdev->dev); if (IS_ERR(bp->ptp_clock)) { pr_err("ptp clock register failed: %ld\n", @@ -345,10 +346,6 @@ void gem_ptp_init(struct net_device *netdev) return; } - spin_lock_init(&bp->tsu_clk_lock); - - gem_ptp_init_tsu(bp); - dev_info(&bp->pdev->dev, "%s ptp clock registered.\n", GEM_PTP_TIMER_NAME); }