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| author | Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> | 2023-11-27 21:24:20 +0900 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2023-11-28 19:54:24 -0800 |
| commit | 9870257a0a338cd8d6c1cddab74e703f490f6779 (patch) | |
| tree | c34e9fbd0bd2e0ab83d3d118e0afc92cfd83e16a | |
| parent | 91d3d149978ba7b238198dd80e4b823756aa7cfa (diff) | |
| download | linux-xfs-9870257a0a338cd8d6c1cddab74e703f490f6779.tar.gz | |
ravb: Fix races between ravb_tx_timeout_work() and net related ops
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@renesas.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
| -rw-r--r-- | drivers/net/ethernet/renesas/ravb_main.c | 11 |
1 files changed, 10 insertions, 1 deletions
diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c index c70cff80cc9993..7c007ecd3ff601 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 @@ out: ravb_ptp_init(ndev, priv->pdev); netif_tx_start_all_queues(ndev); + +out_unlock: + rtnl_unlock(); } /* Packet transmit function for Ethernet AVB */ |