There's no "pernet" variable in the struct hashinfo. The "pernet" variable is introduced from v6.1-rc1. Revert pre-patch and post-patch.
Zhengchao Shao (2): Revert "tcp: Fix NEW_SYN_RECV handling in inet_twsk_purge()" Revert "tcp: Clean up kernel listener's reqsk in inet_twsk_purge()"
net/ipv4/inet_timewait_sock.c | 32 +++++++++++--------------------- 1 file changed, 11 insertions(+), 21 deletions(-)