From: D. Wythe <alibuda@xxxxxxxxxxxxxxxxx>
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@xxxxxxxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
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
@@ -342,8 +342,8 @@ void smc_conn_free(struct smc_connection
} else {
smc_cdc_tx_dismiss_slots(conn);
}
- smc_lgr_unregister_conn(conn);
smc_buf_unuse(conn, lgr); /* allow buffer reuse */
+ smc_lgr_unregister_conn(conn);
conn->lgr = NULL;
if (!lgr->conns_num)
