| From 0537f0a2151375dcf90c1bbfda6a0aaf57164e89 Mon Sep 17 00:00:00 2001 |
| From: "D. Wythe" <alibuda@linux.alibaba.com> |
| Date: Wed, 2 Mar 2022 21:25:11 +0800 |
| Subject: net/smc: fix unexpected SMC_CLC_DECL_ERR_REGRMB error generated by client |
| |
| 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 |
| @@ -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) |
