From 2b52a4b65bc8f14520fe6e996ea7fb3f7e400761 Mon Sep 17 00:00:00 2001 From: Sven Van Asbroeck Date: Mon, 9 Nov 2020 15:38:28 -0500 Subject: lan743x: fix "BUG: invalid wait context" when setting rx mode In the net core, the struct net_device_ops -> ndo_set_rx_mode() callback is called with the dev->addr_list_lock spinlock held. However, this driver's ndo_set_rx_mode callback eventually calls lan743x_dp_write(), which acquires a mutex. Mutex acquisition may sleep, and this is not allowed when holding a spinlock. Fix by removing the dp_lock mutex entirely. Its purpose is to prevent concurrent accesses to the data port. No concurrent accesses are possible, because the dev->addr_list_lock spinlock in the core only lets through one thread at a time. Fixes: 23f0703c125b ("lan743x: Add main source files for new lan743x driver") Signed-off-by: Sven Van Asbroeck Link: https://lore.kernel.org/r/20201109203828.5115-1-TheSven73@gmail.com Signed-off-by: Jakub Kicinski --- drivers/net/ethernet/microchip/lan743x_main.c | 12 +++--------- drivers/net/ethernet/microchip/lan743x_main.h | 3 --- 2 files changed, 3 insertions(+), 12 deletions(-) diff --git a/drivers/net/ethernet/microchip/lan743x_main.c b/drivers/net/ethernet/microchip/lan743x_main.c index bd77877cf1cc..173158656559 100644 --- a/drivers/net/ethernet/microchip/lan743x_main.c +++ b/drivers/net/ethernet/microchip/lan743x_main.c @@ -674,14 +674,12 @@ clean_up: static int lan743x_dp_write(struct lan743x_adapter *adapter, u32 select, u32 addr, u32 length, u32 *buf) { - int ret = -EIO; u32 dp_sel; int i; - mutex_lock(&adapter->dp_lock); if (lan743x_csr_wait_for_bit(adapter, DP_SEL, DP_SEL_DPRDY_, 1, 40, 100, 100)) - goto unlock; + return -EIO; dp_sel = lan743x_csr_read(adapter, DP_SEL); dp_sel &= ~DP_SEL_MASK_; dp_sel |= select; @@ -693,13 +691,10 @@ static int lan743x_dp_write(struct lan743x_adapter *adapter, lan743x_csr_write(adapter, DP_CMD, DP_CMD_WRITE_); if (lan743x_csr_wait_for_bit(adapter, DP_SEL, DP_SEL_DPRDY_, 1, 40, 100, 100)) - goto unlock; + return -EIO; } - ret = 0; -unlock: - mutex_unlock(&adapter->dp_lock); - return ret; + return 0; } static u32 lan743x_mac_mii_access(u16 id, u16 index, int read) @@ -2735,7 +2730,6 @@ static int lan743x_hardware_init(struct lan743x_adapter *adapter, adapter->intr.irq = adapter->pdev->irq; lan743x_csr_write(adapter, INT_EN_CLR, 0xFFFFFFFF); - mutex_init(&adapter->dp_lock); ret = lan743x_gpio_init(adapter); if (ret) diff --git a/drivers/net/ethernet/microchip/lan743x_main.h b/drivers/net/ethernet/microchip/lan743x_main.h index c61a40411317..a536f4a4994d 100644 --- a/drivers/net/ethernet/microchip/lan743x_main.h +++ b/drivers/net/ethernet/microchip/lan743x_main.h @@ -712,9 +712,6 @@ struct lan743x_adapter { struct lan743x_csr csr; struct lan743x_intr intr; - /* lock, used to prevent concurrent access to data port */ - struct mutex dp_lock; - struct lan743x_gpio gpio; struct lan743x_ptp ptp; -- cgit v1.2.3