From 1b2f8d7cc1b2a9a6de1ba349a70da0a2496966fa Mon Sep 17 00:00:00 2001 From: Yonglong Liu Date: Sat, 15 Dec 2018 11:53:23 +0800 Subject: [PATCH] net: hns: Fixed bug that netdev was opened twice [ Upstream commit 5778b13b64eca5549d242686f2f91a2c80c8fa40 ] After resetting dsaf to try to repair chip error such as ecc error, the net device will be open if net interface is up. But at this time if there is the users set the net device up with the command ifconfig, the net device will be opened twice consecutively. Function napi_enable was called when open device. And Kernel panic will be occurred if it was called twice consecutively. Such as follow: static inline void napi_enable(struct napi_struct *n) { BUG_ON(!test_bit(NAPI_STATE_SCHED, &n->state)); smp_mb__before_clear_bit(); clear_bit(NAPI_STATE_SCHED, &n->state); } [37255.571996] Kernel panic - not syncing: BUG! [37255.595234] Call trace: [37255.597694] [] dump_backtrace+0x0/0x1a0 [37255.603114] [] show_stack+0x20/0x28 [37255.608187] [] dump_stack+0x98/0xb8 [37255.613258] [] panic+0x10c/0x26c [37255.618070] [] hns_nic_net_up+0x30c/0x4e0 [37255.623664] [] hns_nic_net_open+0x94/0x12c [37255.629346] [] __dev_open+0xf4/0x168 [37255.634504] [] __dev_change_flags+0x98/0x15c [37255.640359] [] dev_change_flags+0x2c/0x68 [37255.769580] [] devinet_ioctl+0x650/0x704 [37255.775086] [] inet_ioctl+0x98/0xb4 [37255.780159] [] sock_do_ioctl+0x44/0x84 [37255.785490] [] sock_ioctl+0x248/0x30c [37255.790737] [] do_vfs_ioctl+0x480/0x618 [37255.796156] [] SyS_ioctl+0x90/0xa4 [37255.801139] SMP: stopping secondary CPUs [37255.805079] kbox: catch panic event. [37255.809586] collected_len = 128928, LOG_BUF_LEN_LOCAL = 131072 [37255.816103] flush cache 0xffff80003f000000 size 0x800000 [37255.822192] flush cache 0xffff80003f000000 size 0x800000 [37255.828289] flush cache 0xffff80003f000000 size 0x800000 [37255.834378] kbox: no notify die func register. no need to notify [37255.840413] ---[ end Kernel panic - not syncing: BUG! This patchset fix this bug according to the flag NIC_STATE_DOWN. Signed-off-by: Yonglong Liu Signed-off-by: Peng Li Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- drivers/net/ethernet/hisilicon/hns/hns_enet.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/net/ethernet/hisilicon/hns/hns_enet.c b/drivers/net/ethernet/hisilicon/hns/hns_enet.c index c205a0e..c9454c4 100644 --- a/drivers/net/ethernet/hisilicon/hns/hns_enet.c +++ b/drivers/net/ethernet/hisilicon/hns/hns_enet.c @@ -1333,6 +1333,9 @@ static int hns_nic_net_up(struct net_device *ndev) int i, j; int ret; + if (!test_bit(NIC_STATE_DOWN, &priv->state)) + return 0; + ret = hns_nic_init_irq(priv); if (ret != 0) { netdev_err(ndev, "hns init irq failed! ret=%d\n", ret); -- 2.7.4