Ceph volumes hang or stall when iptables/nftables is running

Issue

• Whenever we start virtual machines backed by a Ceph volume, disk I/O on these VMs will stall soon after the initial boot. dmesg of affected machines contains the following messages:

[  615.074762]       Not tainted 4.18.0-147.el8.x86_64 #1
[  615.075418] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[  615.076434] xfsaild/vda1    D    0   416      2 0x80000000
[  615.077173] Call Trace:
[  615.077512]  ? __schedule+0x253/0x830
[  615.077997]  schedule+0x28/0x70
[  615.078563]  xfs_log_force+0x160/0x2e0 [xfs]
[  615.079155]  ? wake_up_q+0x70/0x70
[  615.079628]  xfsaild+0x17b/0x7f0 [xfs]
[  615.080161]  ? xfs_trans_ail_cursor_first+0x80/0x80 [xfs]
[  615.080864]  kthread+0x112/0x130
[  615.081286]  ? kthread_flush_work_fn+0x10/0x10
[  615.081880]  ret_from_fork+0x35/0x40

• Another footprint is that Ceph Volume creation can hang or take a long time.