From: Gerd Rausch Date: Thu, 22 Jan 2026 05:52:12 +0000 (-0700) Subject: net/rds: No shortcut out of RDS_CONN_ERROR X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=ad22d24be635c6beab6a1fdd3f8b1f3c478d15da;p=thirdparty%2Fkernel%2Flinux.git net/rds: No shortcut out of RDS_CONN_ERROR RDS connections carry a state "rds_conn_path::cp_state" and transitions from one state to another and are conditional upon an expected state: "rds_conn_path_transition." There is one exception to this conditionality, which is "RDS_CONN_ERROR" that can be enforced by "rds_conn_path_drop" regardless of what state the condition is currently in. But as soon as a connection enters state "RDS_CONN_ERROR", the connection handling code expects it to go through the shutdown-path. The RDS/TCP multipath changes added a shortcut out of "RDS_CONN_ERROR" straight back to "RDS_CONN_CONNECTING" via "rds_tcp_accept_one_path" (e.g. after "rds_tcp_state_change"). A subsequent "rds_tcp_reset_callbacks" can then transition the state to "RDS_CONN_RESETTING" with a shutdown-worker queued. That'll trip up "rds_conn_init_shutdown", which was never adjusted to handle "RDS_CONN_RESETTING" and subsequently drops the connection with the dreaded "DR_INV_CONN_STATE", which leaves "RDS_SHUTDOWN_WORK_QUEUED" on forever. So we do two things here: a) Don't shortcut "RDS_CONN_ERROR", but take the longer path through the shutdown code. b) Add "RDS_CONN_RESETTING" to the expected states in "rds_conn_init_shutdown" so that we won't error out and get stuck, if we ever hit weird state transitions like this again." Signed-off-by: Gerd Rausch Signed-off-by: Allison Henderson Link: https://patch.msgid.link/20260122055213.83608-2-achender@kernel.org Signed-off-by: Jakub Kicinski --- diff --git a/net/rds/connection.c b/net/rds/connection.c index e920c685e4f2..4a9d80d56f56 100644 --- a/net/rds/connection.c +++ b/net/rds/connection.c @@ -395,6 +395,8 @@ void rds_conn_shutdown(struct rds_conn_path *cp) if (!rds_conn_path_transition(cp, RDS_CONN_UP, RDS_CONN_DISCONNECTING) && !rds_conn_path_transition(cp, RDS_CONN_ERROR, + RDS_CONN_DISCONNECTING) && + !rds_conn_path_transition(cp, RDS_CONN_RESETTING, RDS_CONN_DISCONNECTING)) { rds_conn_path_error(cp, "shutdown called in state %d\n", diff --git a/net/rds/tcp_listen.c b/net/rds/tcp_listen.c index 820d3e20de19..27b6107ddc28 100644 --- a/net/rds/tcp_listen.c +++ b/net/rds/tcp_listen.c @@ -59,9 +59,6 @@ void rds_tcp_keepalive(struct socket *sock) * socket and force a reconneect from smaller -> larger ip addr. The reason * we special case cp_index 0 is to allow the rds probe ping itself to itself * get through efficiently. - * Since reconnects are only initiated from the node with the numerically - * smaller ip address, we recycle conns in RDS_CONN_ERROR on the passive side - * by moving them to CONNECTING in this function. */ static struct rds_tcp_connection *rds_tcp_accept_one_path(struct rds_connection *conn) @@ -86,8 +83,6 @@ struct rds_tcp_connection *rds_tcp_accept_one_path(struct rds_connection *conn) struct rds_conn_path *cp = &conn->c_path[i]; if (rds_conn_path_transition(cp, RDS_CONN_DOWN, - RDS_CONN_CONNECTING) || - rds_conn_path_transition(cp, RDS_CONN_ERROR, RDS_CONN_CONNECTING)) { return cp->cp_transport_data; }