Unreclaimable slab growth in kmalloc-2048 due to an issue with 'vrouter' module.

Issue

• The system is getting into hang or OOM due to unreclaimable slab growth in 'kmalloc-2048'.

$ less /proc/meminfo  |grep ^S
Slab:            3134324 kB
SReclaimable:     199712 kB
SUnreclaim:      2934612 kB

$ cat /proc/slabinfo |awk '{printf "%7i MiB : %s\n",$6*$(NF-1)/256,$1}'|sort -nk 1 -r|head -5
   2544 MiB : kmalloc-2048
    141 MiB : kmalloc-256
     48 MiB : buffer_head
     44 MiB : dentry
     38 MiB : xfs_inode