| From foo@baz Sat 28 Dec 2019 06:10:39 AM EST |
| From: Mao Wenan <maowenan@huawei.com> |
| Date: Mon, 9 Dec 2019 21:31:25 +0800 |
| Subject: af_packet: set defaule value for tmo |
| |
| From: Mao Wenan <maowenan@huawei.com> |
| |
| [ Upstream commit b43d1f9f7067c6759b1051e8ecb84e82cef569fe ] |
| |
| There is softlockup when using TPACKET_V3: |
| ... |
| NMI watchdog: BUG: soft lockup - CPU#2 stuck for 60010ms! |
| (__irq_svc) from [<c0558a0c>] (_raw_spin_unlock_irqrestore+0x44/0x54) |
| (_raw_spin_unlock_irqrestore) from [<c027b7e8>] (mod_timer+0x210/0x25c) |
| (mod_timer) from [<c0549c30>] |
| (prb_retire_rx_blk_timer_expired+0x68/0x11c) |
| (prb_retire_rx_blk_timer_expired) from [<c027a7ac>] |
| (call_timer_fn+0x90/0x17c) |
| (call_timer_fn) from [<c027ab6c>] (run_timer_softirq+0x2d4/0x2fc) |
| (run_timer_softirq) from [<c021eaf4>] (__do_softirq+0x218/0x318) |
| (__do_softirq) from [<c021eea0>] (irq_exit+0x88/0xac) |
| (irq_exit) from [<c0240130>] (msa_irq_exit+0x11c/0x1d4) |
| (msa_irq_exit) from [<c0209cf0>] (handle_IPI+0x650/0x7f4) |
| (handle_IPI) from [<c02015bc>] (gic_handle_irq+0x108/0x118) |
| (gic_handle_irq) from [<c0558ee4>] (__irq_usr+0x44/0x5c) |
| ... |
| |
| If __ethtool_get_link_ksettings() is failed in |
| prb_calc_retire_blk_tmo(), msec and tmo will be zero, so tov_in_jiffies |
| is zero and the timer expire for retire_blk_timer is turn to |
| mod_timer(&pkc->retire_blk_timer, jiffies + 0), |
| which will trigger cpu usage of softirq is 100%. |
| |
| Fixes: f6fb8f100b80 ("af-packet: TPACKET_V3 flexible buffer implementation.") |
| Tested-by: Xiao Jiangfeng <xiaojiangfeng@huawei.com> |
| Signed-off-by: Mao Wenan <maowenan@huawei.com> |
| Signed-off-by: David S. Miller <davem@davemloft.net> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| --- |
| net/packet/af_packet.c | 3 ++- |
| 1 file changed, 2 insertions(+), 1 deletion(-) |
| |
| --- a/net/packet/af_packet.c |
| +++ b/net/packet/af_packet.c |
| @@ -584,7 +584,8 @@ static int prb_calc_retire_blk_tmo(struc |
| msec = 1; |
| div = speed / 1000; |
| } |
| - } |
| + } else |
| + return DEFAULT_PRB_RETIRE_TOV; |
| |
| mbits = (blk_size_in_bytes * 8) / (1024 * 1024); |
| |