Hi David Thanks a lot for Review, I have raised v2 after addressing your review comments from https://lkml.org/lkml/2021/1/14/1400. List of changes in v2: --- 1.) Replace accept_ra_defrtr_metric with ra_defrtr_metric. 2.) Change Type to __u32 instead of __s32. 3.) Change description in Documentation/networking/ip-sysctl.rst. 4.) Use proc_douintvec instead of proc_dointvec. 5.) Code style in ndisc_router_discovery(). 6.) Change Type to u32 instead of unsigned int. --- Thanks a lot again for help.