r8169 take too long to complete driver initialization

From: Chris Chiu
Date: Wed Dec 20 2017 - 03:41:54 EST

We've hit a suspend/resume issue on a Acer desktop caused by r8169
driver. The dmseg
shows it's still in msleep() within a mutex lock.
After looking into the code, it's caused by the
rtl8168ep_stop_cmac() which is waiting 100 seconds for
rtl_ocp_tx_cond. The following dmesg states that the r8169 driver is

[ 20.270526] r8169 Gigabit Ethernet driver 2.3LK-NAPI loaded

But it takes > 100 seconds to get the following messages

[ 140.400223] r8169 0000:02:00.0 (unnamed net_device)
(uninitialized): rtl_ocp_tx_cond == 1 (loop: 2000, delay: 50).
[ 140.413294] r8169 0000:02:00.0 eth0: RTL8168ep/8111ep at
0xffffb16c80db1000, f8:0f:41:ea:74:0d, XID 10200800 IRQ 46
[ 140.413297] r8169 0000:02:00.0 eth0: jumbo features [frames: 9200
bytes, tx checksumming: ko]

So any trial to suspend the machine during this period would always
get device/resource busy message then abort. Is this rtl_ocp_tx_cond
necessary? Because the ethernet is still working and I don't see any
problem. I don't know it should be considered normal or not. Please
let me know if any more information required. Thanks