[PATCH] enic: Fix another sleep-in-atomic bug

From: Jia-Ju Bai
Date: Tue May 30 2017 - 22:41:55 EST


The driver may sleep under a spin lock in some function call paths.
The 1st function call path is:
enic_tx_hang_reset (acquire the lock by spin_lock)
enic_stop
enic_synchronize_irqs
synchronize_irq --> may sleep
The 2nd function call path is:
enic_tx_hang_reset (acquire the lock by spin_lock)
enic_dev_wait
schedule_timeout_uninterruptible --> may sleep
The 3rd function call path is:
enic_tx_hang_reset (acquire the lock by spin_lock)
enic_open
enic_request_intr
enic_set_rx_cpu_rmap
enic_free_rx_cpu_rmap
free_irq_cpu_rmap --> may sleep

To fix it, the "spin_lock" and "spin_unlock" are removed
in enic_tx_hang_reset.

Signed-off-by: Jia-Ju Bai <baijiaju1990@xxxxxxx>
---
drivers/net/ethernet/cisco/enic/enic_main.c | 2 --
1 file changed, 2 deletions(-)

diff --git a/drivers/net/ethernet/cisco/enic/enic_main.c b/drivers/net/ethernet/cisco/enic/enic_main.c
index 4b87bee..d6523e2 100644
--- a/drivers/net/ethernet/cisco/enic/enic_main.c
+++ b/drivers/net/ethernet/cisco/enic/enic_main.c
@@ -2330,7 +2330,6 @@ static void enic_tx_hang_reset(struct work_struct *work)

rtnl_lock();

- spin_lock(&enic->enic_api_lock);
enic_dev_hang_notify(enic);
enic_stop(enic->netdev);
enic_dev_hang_reset(enic);
@@ -2339,7 +2338,6 @@ static void enic_tx_hang_reset(struct work_struct *work)
enic_set_rss_nic_cfg(enic);
enic_dev_set_ig_vlan_rewrite_mode(enic);
enic_open(enic->netdev);
- spin_unlock(&enic->enic_api_lock);
call_netdevice_notifiers(NETDEV_REBOOT, enic->netdev);

rtnl_unlock();
--
1.7.9.5