From b6f4a62ba7a07c546d71c14a94be1c4481a65b1a Mon Sep 17 00:00:00 2001 From: Ido Schimmel Date: Thu, 27 Apr 2023 08:25:21 +0300 Subject: devlink: Fix dumps where interface map is used The devlink utility stores an interface map that can be used to map an interface name to a devlink port and vice versa. The map is populated by issuing a devlink port dump via 'DEVLINK_CMD_PORT_GET' command. Cited commits started to populate the map only when it is actually needed. One such case is when a dump (e.g., shared buffer dump) only returns devlink port handles. When pretty printing is required, the utility will consult the map to translate the devlink port handles to the corresponding interface names. The above is problematic as it means that the port dump response(s) will be queued to the same receive buffer as the response(s) of the dump that triggered the port dump, resulting in a failed dump [1]. Fix by using a different netlink socket for the population of the interface map. [1] $ devlink sb tc bind show kernel answers: Device or resource busy Failed to create index map //0: sb 0 tc 4 type egress pool 4 threshold 9 kernel answers: Device or resource busy [...] $ echo $? 1 Fixes: 5cddbb274eab ("devlink: load port-ifname map on demand") Fixes: 63d84b1fc98d ("devlink: load ifname map on demand from ifname_map_rev_lookup() as well") Signed-off-by: Ido Schimmel Signed-off-by: Stephen Hemminger --- devlink/devlink.c | 18 ++++++++++++------ 1 file changed, 12 insertions(+), 6 deletions(-) diff --git a/devlink/devlink.c b/devlink/devlink.c index 795f8318..019ffc23 100644 --- a/devlink/devlink.c +++ b/devlink/devlink.c @@ -931,6 +931,7 @@ static void ifname_map_init(struct dl *dl) static int ifname_map_load(struct dl *dl, const char *ifname) { + struct mnlu_gen_socket nlg_map; struct nlmsghdr *nlh; int err; @@ -943,15 +944,20 @@ static int ifname_map_load(struct dl *dl, const char *ifname) */ } - nlh = mnlu_gen_socket_cmd_prepare(&dl->nlg, DEVLINK_CMD_PORT_GET, + err = mnlu_gen_socket_open(&nlg_map, DEVLINK_GENL_NAME, + DEVLINK_GENL_VERSION); + if (err) + return err; + + nlh = mnlu_gen_socket_cmd_prepare(&nlg_map, DEVLINK_CMD_PORT_GET, NLM_F_REQUEST | NLM_F_ACK | NLM_F_DUMP); - err = mnlu_gen_socket_sndrcv(&dl->nlg, nlh, ifname_map_cb, dl); - if (err) { + err = mnlu_gen_socket_sndrcv(&nlg_map, nlh, ifname_map_cb, dl); + if (err) ifname_map_fini(dl); - return err; - } - return 0; + + mnlu_gen_socket_close(&nlg_map); + return err; } static int ifname_map_check_load(struct dl *dl, const char *ifname) -- cgit v1.2.1