From: D. Wythe alibuda@linux.alibaba.com
commit 0537f0a2151375dcf90c1bbfda6a0aaf57164e89 upstream.
The main reason for this unexpected SMC_CLC_DECL_ERR_REGRMB in client dues to following execution sequence:
Server Conn A: Server Conn B: Client Conn B:
smc_lgr_unregister_conn smc_lgr_register_conn smc_clc_send_accept -> smc_rtoken_add smcr_buf_unuse -> Client Conn A: smc_rtoken_delete
smc_lgr_unregister_conn() makes current link available to assigned to new incoming connection, while smcr_buf_unuse() has not executed yet, which means that smc_rtoken_add may fail because of insufficient rtoken_entry, reversing their execution order will avoid this problem.
Fixes: 3e034725c0d8 ("net/smc: common functions for RMBs and send buffers") Signed-off-by: D. Wythe alibuda@linux.alibaba.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/smc/smc_core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/net/smc/smc_core.c +++ b/net/smc/smc_core.c @@ -1132,8 +1132,8 @@ void smc_conn_free(struct smc_connection cancel_work_sync(&conn->abort_work); } if (!list_empty(&lgr->list)) { - smc_lgr_unregister_conn(conn); smc_buf_unuse(conn, lgr); /* allow buffer reuse */ + smc_lgr_unregister_conn(conn); }
if (!lgr->conns_num)