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authorSven Van Asbroeck <thesven73@gmail.com>2020-11-09 15:38:28 -0500
committerJakub Kicinski <kuba@kernel.org>2020-11-10 17:52:54 -0800
commit2b52a4b65bc8f14520fe6e996ea7fb3f7e400761 (patch)
treeef8debe210f0685a3dee8af7902eb00ae3ea7818 /drivers/net
parent2bae900b9419db3f3e43bbda3194657235fee096 (diff)
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 <thesven73@gmail.com> Link: https://lore.kernel.org/r/20201109203828.5115-1-TheSven73@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'drivers/net')
-rw-r--r--drivers/net/ethernet/microchip/lan743x_main.c12
-rw-r--r--drivers/net/ethernet/microchip/lan743x_main.h3
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;