From: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> stable inclusion from stable-v6.6.5 commit 658dc8b4a3fb0c9c3e67d67c6cdda4107e798a0c category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I8N21P Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- [ Upstream commit 9870257a0a338cd8d6c1cddab74e703f490f6779 ] Fix races between ravb_tx_timeout_work() and functions of net_device_ops and ethtool_ops by using rtnl_trylock() and rtnl_unlock(). Note that since ravb_close() is under the rtnl lock and calls cancel_work_sync(), ravb_tx_timeout_work() should calls rtnl_trylock(). Otherwise, a deadlock may happen in ravb_tx_timeout_work() like below: CPU0 CPU1 ravb_tx_timeout() schedule_work() ... __dev_close_many() // Under rtnl lock ravb_close() cancel_work_sync() // Waiting ravb_tx_timeout_work() rtnl_lock() // This is possible to cause a deadlock If rtnl_trylock() fails, rescheduling the work with sleep for 1 msec. Fixes: c156633f1353 ("Renesas Ethernet AVB driver proper") Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> Reviewed-by: Sergey Shtylyov <s.shtylyov@omp.ru> Link: https://lore.kernel.org/r/20231127122420.3706751-1-yoshihiro.shimoda.uh@rene... Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com> --- drivers/net/ethernet/renesas/ravb_main.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c index 0ef0b88b7145..de12c02c55cb 100644 --- a/drivers/net/ethernet/renesas/ravb_main.c +++ b/drivers/net/ethernet/renesas/ravb_main.c @@ -1874,6 +1874,12 @@ static void ravb_tx_timeout_work(struct work_struct *work) struct net_device *ndev = priv->ndev; int error; + if (!rtnl_trylock()) { + usleep_range(1000, 2000); + schedule_work(&priv->work); + return; + } + netif_tx_stop_all_queues(ndev); /* Stop PTP Clock driver */ @@ -1907,7 +1913,7 @@ static void ravb_tx_timeout_work(struct work_struct *work) */ netdev_err(ndev, "%s: ravb_dmac_init() failed, error %d\n", __func__, error); - return; + goto out_unlock; } ravb_emac_init(ndev); @@ -1917,6 +1923,9 @@ static void ravb_tx_timeout_work(struct work_struct *work) ravb_ptp_init(ndev, priv->pdev); netif_tx_start_all_queues(ndev); + +out_unlock: + rtnl_unlock(); } /* Packet transmit function for Ethernet AVB */ -- 2.20.1