From 17e712c6a1bade9dac02a7bf2b464746faa7e9a0 Mon Sep 17 00:00:00 2001 From: Yinjun Zhang Date: Fri, 29 Oct 2021 13:29:03 +0200 Subject: [PATCH] nfp: fix potential deadlock when canceling dim work When port is linked down, the process which has acquired rtnl_lock will wait for the in-progress dim work to finish, and the work also acquires rtnl_lock, which may cause deadlock. Currently IRQ_MOD registers can be configured by `ethtool -C` and dim work, and which will take effect depends on the execution order, rtnl_lock is useless here, so remove them. Fixes: 9d32e4e7e9e1 ("nfp: add support for coalesce adaptive feature") Signed-off-by: Yinjun Zhang Signed-off-by: Louis Peens Signed-off-by: Simon Horman Signed-off-by: David S. Miller --- drivers/net/ethernet/netronome/nfp/nfp_net_common.c | 4 ---- 1 file changed, 4 deletions(-) diff --git a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c index f8b880c8e514..850bfdf83d0a 100644 --- a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c +++ b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c @@ -3016,10 +3016,8 @@ static void nfp_net_rx_dim_work(struct work_struct *work) /* copy RX interrupt coalesce parameters */ value = (moder.pkts << 16) | (factor * moder.usec); - rtnl_lock(); nn_writel(nn, NFP_NET_CFG_RXR_IRQ_MOD(r_vec->rx_ring->idx), value); (void)nfp_net_reconfig(nn, NFP_NET_CFG_UPDATE_IRQMOD); - rtnl_unlock(); dim->state = DIM_START_MEASURE; } @@ -3047,10 +3045,8 @@ static void nfp_net_tx_dim_work(struct work_struct *work) /* copy TX interrupt coalesce parameters */ value = (moder.pkts << 16) | (factor * moder.usec); - rtnl_lock(); nn_writel(nn, NFP_NET_CFG_TXR_IRQ_MOD(r_vec->tx_ring->idx), value); (void)nfp_net_reconfig(nn, NFP_NET_CFG_UPDATE_IRQMOD); - rtnl_unlock(); dim->state = DIM_START_MEASURE; }