[PATCH net 0/5] rxrpc: Fixes

[PATCH net 0/5] rxrpc: Fixes

[David Howells]

Here are three fixes for AF_RXRPC and two tracepoints that were useful for
finding them:

 (1) Fix missing start of expect-Rx-by timeout on initial packet
     transmission so that calls will time out if the peer doesn't respond.

 (2) Fix error reception on AF_INET6 sockets by using the correct family of
     sockopts on the UDP transport socket.

 (3) Fix setting the minimum security level on kernel calls so that they
     can be encrypted.

 (4) Add a tracepoint to log ICMP/ICMP6 and other error reports from the
     transport socket.

 (5) Add a tracepoint to log UDP sendmsg failure so that we can find out if
     transmission failure occurred on the UDP socket.

The patches are tagged here:

	git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs.git
	rxrpc-fixes-20180510

and can also be found on the following branch:

	http://git.kernel.org/cgit/linux/kernel/git/dhowells/linux-fs.git/log/?h=rxrpc-fixes

David
---
David Howells (5):
      rxrpc: Fix missing start of call timeout
      rxrpc: Fix error reception on AF_INET6 sockets
      rxrpc: Fix the min security level for kernel calls
      rxrpc: Add a tracepoint to log ICMP/ICMP6 and error messages
      rxrpc: Trace UDP transmission failure


 include/trace/events/rxrpc.h |   85 ++++++++++++++++++++++++++++++++++++++++++
 net/rxrpc/af_rxrpc.c         |    2 -
 net/rxrpc/ar-internal.h      |    1 
 net/rxrpc/conn_event.c       |   11 ++++-
 net/rxrpc/input.c            |    2 -
 net/rxrpc/local_event.c      |    3 +
 net/rxrpc/local_object.c     |   57 +++++++++++++++++++++-------
 net/rxrpc/output.c           |   34 ++++++++++++++++-
 net/rxrpc/peer_event.c       |   46 +++++++++++------------
 net/rxrpc/rxkad.c            |    6 ++-
 net/rxrpc/sendmsg.c          |   10 +++++
 11 files changed, 209 insertions(+), 48 deletions(-)

[PATCH net 1/5] rxrpc: Fix missing start of call timeout

[David Howells]

The expect_rx_by call timeout is supposed to be set when a call is started
to indicate that we need to receive a packet by that point.  This is
currently put back every time we receive a packet, but it isn't started
when we first send a packet.  Without this, the call may wait forever if
the server doesn't deign to reply.

Fix this by setting the timeout upon a successful UDP sendmsg call for the
first DATA packet.  The timeout is initiated only for initial transmission
and not for subsequent retries as we don't want the retry mechanism to
extend the timeout indefinitely.

Fixes: a158bdd3247b ("rxrpc: Fix call timeouts")
Reported-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
---

 net/rxrpc/ar-internal.h |    1 +
 net/rxrpc/input.c       |    2 +-
 net/rxrpc/output.c      |   11 +++++++++++
 net/rxrpc/sendmsg.c     |   10 ++++++++++
 4 files changed, 23 insertions(+), 1 deletion(-)

diff --git a/net/rxrpc/ar-internal.h b/net/rxrpc/ar-internal.h
index 90d7079e0aa9..19975d2ca9a2 100644
--- a/net/rxrpc/ar-internal.h
+++ b/net/rxrpc/ar-internal.h
@@ -476,6 +476,7 @@ enum rxrpc_call_flag {
 	RXRPC_CALL_SEND_PING,		/* A ping will need to be sent */
 	RXRPC_CALL_PINGING,		/* Ping in process */
 	RXRPC_CALL_RETRANS_TIMEOUT,	/* Retransmission due to timeout occurred */
+	RXRPC_CALL_BEGAN_RX_TIMER,	/* We began the expect_rx_by timer */
 };
 
 /*
diff --git a/net/rxrpc/input.c b/net/rxrpc/input.c
index 0410d2277ca2..b5fd6381313d 100644
--- a/net/rxrpc/input.c
+++ b/net/rxrpc/input.c
@@ -971,7 +971,7 @@ static void rxrpc_input_call_packet(struct rxrpc_call *call,
 	if (timo) {
 		unsigned long now = jiffies, expect_rx_by;
 
-		expect_rx_by = jiffies + timo;
+		expect_rx_by = now + timo;
 		WRITE_ONCE(call->expect_rx_by, expect_rx_by);
 		rxrpc_reduce_call_timer(call, expect_rx_by, now,
 					rxrpc_timer_set_for_normal);
diff --git a/net/rxrpc/output.c b/net/rxrpc/output.c
index 7f1fc04775b3..6b9d27f0d7ec 100644
--- a/net/rxrpc/output.c
+++ b/net/rxrpc/output.c
@@ -414,6 +414,17 @@ int rxrpc_send_data_packet(struct rxrpc_call *call, struct sk_buff *skb,
 							rxrpc_timer_set_for_lost_ack);
 			}
 		}
+
+		if (sp->hdr.seq == 1 &&
+		    !test_and_set_bit(RXRPC_CALL_BEGAN_RX_TIMER,
+				      &call->flags)) {
+			unsigned long nowj = jiffies, expect_rx_by;
+
+			expect_rx_by = nowj + call->next_rx_timo;
+			WRITE_ONCE(call->expect_rx_by, expect_rx_by);
+			rxrpc_reduce_call_timer(call, expect_rx_by, nowj,
+						rxrpc_timer_set_for_normal);
+		}
 	}
 
 	rxrpc_set_keepalive(call);
diff --git a/net/rxrpc/sendmsg.c b/net/rxrpc/sendmsg.c
index 206e802ccbdc..be01f9c5d963 100644
--- a/net/rxrpc/sendmsg.c
+++ b/net/rxrpc/sendmsg.c
@@ -223,6 +223,15 @@ static void rxrpc_queue_packet(struct rxrpc_sock *rx, struct rxrpc_call *call,
 
 	ret = rxrpc_send_data_packet(call, skb, false);
 	if (ret < 0) {
+		switch (ret) {
+		case -ENETUNREACH:
+		case -EHOSTUNREACH:
+		case -ECONNREFUSED:
+			rxrpc_set_call_completion(call,
+						  RXRPC_CALL_LOCAL_ERROR,
+						  0, ret);
+			goto out;
+		}
 		_debug("need instant resend %d", ret);
 		rxrpc_instant_resend(call, ix);
 	} else {
@@ -241,6 +250,7 @@ static void rxrpc_queue_packet(struct rxrpc_sock *rx, struct rxrpc_call *call,
 					rxrpc_timer_set_for_send);
 	}
 
+out:
 	rxrpc_free_skb(skb, rxrpc_skb_tx_freed);
 	_leave("");
 }

[PATCH net 2/5] rxrpc: Fix error reception on AF_INET6 sockets

[David Howells]

AF_RXRPC tries to turn on IP_RECVERR and IP_MTU_DISCOVER on the UDP socket
it just opened for communications with the outside world, regardless of the
type of socket.  Unfortunately, this doesn't work with an AF_INET6 socket.

Fix this by turning on IPV6_RECVERR and IPV6_MTU_DISCOVER instead if the
socket is of the AF_INET6 family.

Without this, kAFS server and address rotation doesn't work correctly
because the algorithm doesn't detect received network errors.

Fixes: 75b54cb57ca3 ("rxrpc: Add IPv6 support")
Signed-off-by: David Howells <dhowells@redhat.com>
---

 net/rxrpc/local_object.c |   57 ++++++++++++++++++++++++++++++++++------------
 1 file changed, 42 insertions(+), 15 deletions(-)

diff --git a/net/rxrpc/local_object.c b/net/rxrpc/local_object.c
index 8b54e9531d52..b493e6b62740 100644
--- a/net/rxrpc/local_object.c
+++ b/net/rxrpc/local_object.c
@@ -134,22 +134,49 @@ static int rxrpc_open_socket(struct rxrpc_local *local, struct net *net)
 		}
 	}
 
-	/* we want to receive ICMP errors */
-	opt = 1;
-	ret = kernel_setsockopt(local->socket, SOL_IP, IP_RECVERR,
-				(char *) &opt, sizeof(opt));
-	if (ret < 0) {
-		_debug("setsockopt failed");
-		goto error;
-	}
+	switch (local->srx.transport.family) {
+	case AF_INET:
+		/* we want to receive ICMP errors */
+		opt = 1;
+		ret = kernel_setsockopt(local->socket, SOL_IP, IP_RECVERR,
+					(char *) &opt, sizeof(opt));
+		if (ret < 0) {
+			_debug("setsockopt failed");
+			goto error;
+		}
 
-	/* we want to set the don't fragment bit */
-	opt = IP_PMTUDISC_DO;
-	ret = kernel_setsockopt(local->socket, SOL_IP, IP_MTU_DISCOVER,
-				(char *) &opt, sizeof(opt));
-	if (ret < 0) {
-		_debug("setsockopt failed");
-		goto error;
+		/* we want to set the don't fragment bit */
+		opt = IP_PMTUDISC_DO;
+		ret = kernel_setsockopt(local->socket, SOL_IP, IP_MTU_DISCOVER,
+					(char *) &opt, sizeof(opt));
+		if (ret < 0) {
+			_debug("setsockopt failed");
+			goto error;
+		}
+		break;
+
+	case AF_INET6:
+		/* we want to receive ICMP errors */
+		opt = 1;
+		ret = kernel_setsockopt(local->socket, SOL_IPV6, IPV6_RECVERR,
+					(char *) &opt, sizeof(opt));
+		if (ret < 0) {
+			_debug("setsockopt failed");
+			goto error;
+		}
+
+		/* we want to set the don't fragment bit */
+		opt = IPV6_PMTUDISC_DO;
+		ret = kernel_setsockopt(local->socket, SOL_IPV6, IPV6_MTU_DISCOVER,
+					(char *) &opt, sizeof(opt));
+		if (ret < 0) {
+			_debug("setsockopt failed");
+			goto error;
+		}
+		break;
+
+	default:
+		BUG();
 	}
 
 	/* set the socket up */

[PATCH net 3/5] rxrpc: Fix the min security level for kernel calls

[David Howells]

Fix the kernel call initiation to set the minimum security level for kernel
initiated calls (such as from kAFS) from the sockopt value.

Fixes: 19ffa01c9c45 ("rxrpc: Use structs to hold connection params and protocol info")
Signed-off-by: David Howells <dhowells@redhat.com>
---

 net/rxrpc/af_rxrpc.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/rxrpc/af_rxrpc.c b/net/rxrpc/af_rxrpc.c
index 9a2c8e7c000e..2b463047dd7b 100644
--- a/net/rxrpc/af_rxrpc.c
+++ b/net/rxrpc/af_rxrpc.c
@@ -313,7 +313,7 @@ struct rxrpc_call *rxrpc_kernel_begin_call(struct socket *sock,
 	memset(&cp, 0, sizeof(cp));
 	cp.local		= rx->local;
 	cp.key			= key;
-	cp.security_level	= 0;
+	cp.security_level	= rx->min_sec_level;
 	cp.exclusive		= false;
 	cp.upgrade		= upgrade;
 	cp.service_id		= srx->srx_service;

[PATCH net 4/5] rxrpc: Add a tracepoint to log ICMP/ICMP6 and error messages

[David Howells]

Add a tracepoint to log received ICMP/ICMP6 events and other error
messages.

Signed-off-by: David Howells <dhowells@redhat.com>
---

 include/trace/events/rxrpc.h |   30 +++++++++++++++++++++++++++
 net/rxrpc/peer_event.c       |   46 +++++++++++++++++++++---------------------
 2 files changed, 53 insertions(+), 23 deletions(-)

diff --git a/include/trace/events/rxrpc.h b/include/trace/events/rxrpc.h
index 9e96c2fe2793..497d0b67f421 100644
--- a/include/trace/events/rxrpc.h
+++ b/include/trace/events/rxrpc.h
@@ -15,6 +15,7 @@
 #define _TRACE_RXRPC_H
 
 #include <linux/tracepoint.h>
+#include <linux/errqueue.h>
 
 /*
  * Define enums for tracing information.
@@ -1374,6 +1375,35 @@ TRACE_EVENT(rxrpc_resend,
 		      __entry->anno)
 	    );
 
+TRACE_EVENT(rxrpc_rx_icmp,
+	    TP_PROTO(struct rxrpc_peer *peer, struct sock_extended_err *ee,
+		     struct sockaddr_rxrpc *srx),
+
+	    TP_ARGS(peer, ee, srx),
+
+	    TP_STRUCT__entry(
+		    __field(unsigned int,			peer	)
+		    __field_struct(struct sock_extended_err,	ee	)
+		    __field_struct(struct sockaddr_rxrpc,	srx	)
+			     ),
+
+	    TP_fast_assign(
+		    __entry->peer = peer->debug_id;
+		    memcpy(&__entry->ee, ee, sizeof(__entry->ee));
+		    memcpy(&__entry->srx, srx, sizeof(__entry->srx));
+			   ),
+
+	    TP_printk("P=%08x o=%u t=%u c=%u i=%u d=%u e=%d %pISp",
+		      __entry->peer,
+		      __entry->ee.ee_origin,
+		      __entry->ee.ee_type,
+		      __entry->ee.ee_code,
+		      __entry->ee.ee_info,
+		      __entry->ee.ee_data,
+		      __entry->ee.ee_errno,
+		      &__entry->srx.transport)
+	    );
+
 #endif /* _TRACE_RXRPC_H */
 
 /* This part must be outside protection */
diff --git a/net/rxrpc/peer_event.c b/net/rxrpc/peer_event.c
index 78c2f95d1f22..0ed8b651cec2 100644
--- a/net/rxrpc/peer_event.c
+++ b/net/rxrpc/peer_event.c
@@ -28,39 +28,39 @@ static void rxrpc_store_error(struct rxrpc_peer *, struct sock_exterr_skb *);
  * Find the peer associated with an ICMP packet.
  */
 static struct rxrpc_peer *rxrpc_lookup_peer_icmp_rcu(struct rxrpc_local *local,
-						     const struct sk_buff *skb)
+						     const struct sk_buff *skb,
+						     struct sockaddr_rxrpc *srx)
 {
 	struct sock_exterr_skb *serr = SKB_EXT_ERR(skb);
-	struct sockaddr_rxrpc srx;
 
 	_enter("");
 
-	memset(&srx, 0, sizeof(srx));
-	srx.transport_type = local->srx.transport_type;
-	srx.transport_len = local->srx.transport_len;
-	srx.transport.family = local->srx.transport.family;
+	memset(srx, 0, sizeof(*srx));
+	srx->transport_type = local->srx.transport_type;
+	srx->transport_len = local->srx.transport_len;
+	srx->transport.family = local->srx.transport.family;
 
 	/* Can we see an ICMP4 packet on an ICMP6 listening socket?  and vice
 	 * versa?
 	 */
-	switch (srx.transport.family) {
+	switch (srx->transport.family) {
 	case AF_INET:
-		srx.transport.sin.sin_port = serr->port;
+		srx->transport.sin.sin_port = serr->port;
 		switch (serr->ee.ee_origin) {
 		case SO_EE_ORIGIN_ICMP:
 			_net("Rx ICMP");
-			memcpy(&srx.transport.sin.sin_addr,
+			memcpy(&srx->transport.sin.sin_addr,
 			       skb_network_header(skb) + serr->addr_offset,
 			       sizeof(struct in_addr));
 			break;
 		case SO_EE_ORIGIN_ICMP6:
 			_net("Rx ICMP6 on v4 sock");
-			memcpy(&srx.transport.sin.sin_addr,
+			memcpy(&srx->transport.sin.sin_addr,
 			       skb_network_header(skb) + serr->addr_offset + 12,
 			       sizeof(struct in_addr));
 			break;
 		default:
-			memcpy(&srx.transport.sin.sin_addr, &ip_hdr(skb)->saddr,
+			memcpy(&srx->transport.sin.sin_addr, &ip_hdr(skb)->saddr,
 			       sizeof(struct in_addr));
 			break;
 		}
@@ -68,25 +68,25 @@ static struct rxrpc_peer *rxrpc_lookup_peer_icmp_rcu(struct rxrpc_local *local,
 
 #ifdef CONFIG_AF_RXRPC_IPV6
 	case AF_INET6:
-		srx.transport.sin6.sin6_port = serr->port;
+		srx->transport.sin6.sin6_port = serr->port;
 		switch (serr->ee.ee_origin) {
 		case SO_EE_ORIGIN_ICMP6:
 			_net("Rx ICMP6");
-			memcpy(&srx.transport.sin6.sin6_addr,
+			memcpy(&srx->transport.sin6.sin6_addr,
 			       skb_network_header(skb) + serr->addr_offset,
 			       sizeof(struct in6_addr));
 			break;
 		case SO_EE_ORIGIN_ICMP:
 			_net("Rx ICMP on v6 sock");
-			srx.transport.sin6.sin6_addr.s6_addr32[0] = 0;
-			srx.transport.sin6.sin6_addr.s6_addr32[1] = 0;
-			srx.transport.sin6.sin6_addr.s6_addr32[2] = htonl(0xffff);
-			memcpy(srx.transport.sin6.sin6_addr.s6_addr + 12,
+			srx->transport.sin6.sin6_addr.s6_addr32[0] = 0;
+			srx->transport.sin6.sin6_addr.s6_addr32[1] = 0;
+			srx->transport.sin6.sin6_addr.s6_addr32[2] = htonl(0xffff);
+			memcpy(srx->transport.sin6.sin6_addr.s6_addr + 12,
 			       skb_network_header(skb) + serr->addr_offset,
 			       sizeof(struct in_addr));
 			break;
 		default:
-			memcpy(&srx.transport.sin6.sin6_addr,
+			memcpy(&srx->transport.sin6.sin6_addr,
 			       &ipv6_hdr(skb)->saddr,
 			       sizeof(struct in6_addr));
 			break;
@@ -98,7 +98,7 @@ static struct rxrpc_peer *rxrpc_lookup_peer_icmp_rcu(struct rxrpc_local *local,
 		BUG();
 	}
 
-	return rxrpc_lookup_peer_rcu(local, &srx);
+	return rxrpc_lookup_peer_rcu(local, srx);
 }
 
 /*
@@ -146,6 +146,7 @@ static void rxrpc_adjust_mtu(struct rxrpc_peer *peer, struct sock_exterr_skb *se
 void rxrpc_error_report(struct sock *sk)
 {
 	struct sock_exterr_skb *serr;
+	struct sockaddr_rxrpc srx;
 	struct rxrpc_local *local = sk->sk_user_data;
 	struct rxrpc_peer *peer;
 	struct sk_buff *skb;
@@ -166,7 +167,7 @@ void rxrpc_error_report(struct sock *sk)
 	}
 
 	rcu_read_lock();
-	peer = rxrpc_lookup_peer_icmp_rcu(local, skb);
+	peer = rxrpc_lookup_peer_icmp_rcu(local, skb, &srx);
 	if (peer && !rxrpc_get_peer_maybe(peer))
 		peer = NULL;
 	if (!peer) {
@@ -176,6 +177,8 @@ void rxrpc_error_report(struct sock *sk)
 		return;
 	}
 
+	trace_rxrpc_rx_icmp(peer, &serr->ee, &srx);
+
 	if ((serr->ee.ee_origin == SO_EE_ORIGIN_ICMP &&
 	     serr->ee.ee_type == ICMP_DEST_UNREACH &&
 	     serr->ee.ee_code == ICMP_FRAG_NEEDED)) {
@@ -209,9 +212,6 @@ static void rxrpc_store_error(struct rxrpc_peer *peer,
 
 	ee = &serr->ee;
 
-	_net("Rx Error o=%d t=%d c=%d e=%d",
-	     ee->ee_origin, ee->ee_type, ee->ee_code, ee->ee_errno);
-
 	err = ee->ee_errno;
 
 	switch (ee->ee_origin) {

[PATCH net 5/5] rxrpc: Trace UDP transmission failure

[David Howells]

Add a tracepoint to log transmission failure from the UDP transport socket
being used by AF_RXRPC.

Signed-off-by: David Howells <dhowells@redhat.com>
---

 include/trace/events/rxrpc.h |   55 ++++++++++++++++++++++++++++++++++++++++++
 net/rxrpc/conn_event.c       |   11 ++++++--
 net/rxrpc/local_event.c      |    3 ++
 net/rxrpc/output.c           |   23 ++++++++++++++++--
 net/rxrpc/rxkad.c            |    6 +++--
 5 files changed, 90 insertions(+), 8 deletions(-)

diff --git a/include/trace/events/rxrpc.h b/include/trace/events/rxrpc.h
index 497d0b67f421..077e664ac9a2 100644
--- a/include/trace/events/rxrpc.h
+++ b/include/trace/events/rxrpc.h
@@ -211,6 +211,20 @@ enum rxrpc_congest_change {
 	rxrpc_cong_saw_nack,
 };
 
+enum rxrpc_tx_fail_trace {
+	rxrpc_tx_fail_call_abort,
+	rxrpc_tx_fail_call_ack,
+	rxrpc_tx_fail_call_data_frag,
+	rxrpc_tx_fail_call_data_nofrag,
+	rxrpc_tx_fail_call_final_resend,
+	rxrpc_tx_fail_conn_abort,
+	rxrpc_tx_fail_conn_challenge,
+	rxrpc_tx_fail_conn_response,
+	rxrpc_tx_fail_reject,
+	rxrpc_tx_fail_version_keepalive,
+	rxrpc_tx_fail_version_reply,
+};
+
 #endif /* end __RXRPC_DECLARE_TRACE_ENUMS_ONCE_ONLY */
 
 /*
@@ -438,6 +452,19 @@ enum rxrpc_congest_change {
 	EM(RXRPC_CALL_LOCAL_ERROR,		"LocalError") \
 	E_(RXRPC_CALL_NETWORK_ERROR,		"NetError")
 
+#define rxrpc_tx_fail_traces \
+	EM(rxrpc_tx_fail_call_abort,		"CallAbort") \
+	EM(rxrpc_tx_fail_call_ack,		"CallAck") \
+	EM(rxrpc_tx_fail_call_data_frag,	"CallDataFrag") \
+	EM(rxrpc_tx_fail_call_data_nofrag,	"CallDataNofrag") \
+	EM(rxrpc_tx_fail_call_final_resend,	"CallFinalResend") \
+	EM(rxrpc_tx_fail_conn_abort,		"ConnAbort") \
+	EM(rxrpc_tx_fail_conn_challenge,	"ConnChall") \
+	EM(rxrpc_tx_fail_conn_response,		"ConnResp") \
+	EM(rxrpc_tx_fail_reject,		"Reject") \
+	EM(rxrpc_tx_fail_version_keepalive,	"VerKeepalive") \
+	E_(rxrpc_tx_fail_version_reply,		"VerReply")
+
 /*
  * Export enum symbols via userspace.
  */
@@ -461,6 +488,7 @@ rxrpc_propose_ack_traces;
 rxrpc_propose_ack_outcomes;
 rxrpc_congest_modes;
 rxrpc_congest_changes;
+rxrpc_tx_fail_traces;
 
 /*
  * Now redefine the EM() and E_() macros to map the enums to the strings that
@@ -1404,6 +1432,33 @@ TRACE_EVENT(rxrpc_rx_icmp,
 		      &__entry->srx.transport)
 	    );
 
+TRACE_EVENT(rxrpc_tx_fail,
+	    TP_PROTO(unsigned int debug_id, rxrpc_serial_t serial, int ret,
+		     enum rxrpc_tx_fail_trace what),
+
+	    TP_ARGS(debug_id, serial, ret, what),
+
+	    TP_STRUCT__entry(
+		    __field(unsigned int,		debug_id	)
+		    __field(rxrpc_serial_t,		serial		)
+		    __field(int,			ret		)
+		    __field(enum rxrpc_tx_fail_trace,   what		)
+			     ),
+
+	    TP_fast_assign(
+		    __entry->debug_id = debug_id;
+		    __entry->serial = serial;
+		    __entry->ret = ret;
+		    __entry->what = what;
+			   ),
+
+	    TP_printk("c=%08x r=%x ret=%d %s",
+		      __entry->debug_id,
+		      __entry->serial,
+		      __entry->ret,
+		      __print_symbolic(__entry->what, rxrpc_tx_fail_traces))
+	    );
+
 #endif /* _TRACE_RXRPC_H */
 
 /* This part must be outside protection */
diff --git a/net/rxrpc/conn_event.c b/net/rxrpc/conn_event.c
index c717152070df..1350f1be8037 100644
--- a/net/rxrpc/conn_event.c
+++ b/net/rxrpc/conn_event.c
@@ -40,7 +40,7 @@ static void rxrpc_conn_retransmit_call(struct rxrpc_connection *conn,
 	} __attribute__((packed)) pkt;
 	struct rxrpc_ackinfo ack_info;
 	size_t len;
-	int ioc;
+	int ret, ioc;
 	u32 serial, mtu, call_id, padding;
 
 	_enter("%d", conn->debug_id);
@@ -135,10 +135,13 @@ static void rxrpc_conn_retransmit_call(struct rxrpc_connection *conn,
 		break;
 	}
 
-	kernel_sendmsg(conn->params.local->socket, &msg, iov, ioc, len);
+	ret = kernel_sendmsg(conn->params.local->socket, &msg, iov, ioc, len);
 	conn->params.peer->last_tx_at = ktime_get_real();
+	if (ret < 0)
+		trace_rxrpc_tx_fail(conn->debug_id, serial, ret,
+				    rxrpc_tx_fail_call_final_resend);
+
 	_leave("");
-	return;
 }
 
 /*
@@ -236,6 +239,8 @@ static int rxrpc_abort_connection(struct rxrpc_connection *conn,
 
 	ret = kernel_sendmsg(conn->params.local->socket, &msg, iov, 2, len);
 	if (ret < 0) {
+		trace_rxrpc_tx_fail(conn->debug_id, serial, ret,
+				    rxrpc_tx_fail_conn_abort);
 		_debug("sendmsg failed: %d", ret);
 		return -EAGAIN;
 	}
diff --git a/net/rxrpc/local_event.c b/net/rxrpc/local_event.c
index 93b5d910b4a1..8325f1b86840 100644
--- a/net/rxrpc/local_event.c
+++ b/net/rxrpc/local_event.c
@@ -71,7 +71,8 @@ static void rxrpc_send_version_request(struct rxrpc_local *local,
 
 	ret = kernel_sendmsg(local->socket, &msg, iov, 2, len);
 	if (ret < 0)
-		_debug("sendmsg failed: %d", ret);
+		trace_rxrpc_tx_fail(local->debug_id, 0, ret,
+				    rxrpc_tx_fail_version_reply);
 
 	_leave("");
 }
diff --git a/net/rxrpc/output.c b/net/rxrpc/output.c
index 6b9d27f0d7ec..f03de1c59ba3 100644
--- a/net/rxrpc/output.c
+++ b/net/rxrpc/output.c
@@ -210,6 +210,9 @@ int rxrpc_send_ack_packet(struct rxrpc_call *call, bool ping,
 	if (ping)
 		call->ping_time = now;
 	conn->params.peer->last_tx_at = ktime_get_real();
+	if (ret < 0)
+		trace_rxrpc_tx_fail(call->debug_id, serial, ret,
+				    rxrpc_tx_fail_call_ack);
 
 	if (call->state < RXRPC_CALL_COMPLETE) {
 		if (ret < 0) {
@@ -294,6 +297,10 @@ int rxrpc_send_abort_packet(struct rxrpc_call *call)
 	ret = kernel_sendmsg(conn->params.local->socket,
 			     &msg, iov, 1, sizeof(pkt));
 	conn->params.peer->last_tx_at = ktime_get_real();
+	if (ret < 0)
+		trace_rxrpc_tx_fail(call->debug_id, serial, ret,
+				    rxrpc_tx_fail_call_abort);
+
 
 	rxrpc_put_connection(conn);
 	return ret;
@@ -387,6 +394,9 @@ int rxrpc_send_data_packet(struct rxrpc_call *call, struct sk_buff *skb,
 	conn->params.peer->last_tx_at = ktime_get_real();
 
 	up_read(&conn->params.local->defrag_sem);
+	if (ret < 0)
+		trace_rxrpc_tx_fail(call->debug_id, serial, ret,
+				    rxrpc_tx_fail_call_data_nofrag);
 	if (ret == -EMSGSIZE)
 		goto send_fragmentable;
 
@@ -476,6 +486,10 @@ int rxrpc_send_data_packet(struct rxrpc_call *call, struct sk_buff *skb,
 #endif
 	}
 
+	if (ret < 0)
+		trace_rxrpc_tx_fail(call->debug_id, serial, ret,
+				    rxrpc_tx_fail_call_data_frag);
+
 	up_write(&conn->params.local->defrag_sem);
 	goto done;
 }
@@ -493,6 +507,7 @@ void rxrpc_reject_packets(struct rxrpc_local *local)
 	struct kvec iov[2];
 	size_t size;
 	__be32 code;
+	int ret;
 
 	_enter("%d", local->debug_id);
 
@@ -527,7 +542,10 @@ void rxrpc_reject_packets(struct rxrpc_local *local)
 			whdr.flags	^= RXRPC_CLIENT_INITIATED;
 			whdr.flags	&= RXRPC_CLIENT_INITIATED;
 
-			kernel_sendmsg(local->socket, &msg, iov, 2, size);
+			ret = kernel_sendmsg(local->socket, &msg, iov, 2, size);
+			if (ret < 0)
+				trace_rxrpc_tx_fail(local->debug_id, 0, ret,
+						    rxrpc_tx_fail_reject);
 		}
 
 		rxrpc_free_skb(skb, rxrpc_skb_rx_freed);
@@ -578,7 +596,8 @@ void rxrpc_send_keepalive(struct rxrpc_peer *peer)
 
 	ret = kernel_sendmsg(peer->local->socket, &msg, iov, 2, len);
 	if (ret < 0)
-		_debug("sendmsg failed: %d", ret);
+		trace_rxrpc_tx_fail(peer->debug_id, 0, ret,
+				    rxrpc_tx_fail_version_keepalive);
 
 	peer->last_tx_at = ktime_get_real();
 	_leave("");
diff --git a/net/rxrpc/rxkad.c b/net/rxrpc/rxkad.c
index 588fea0dd362..6c0ae27fff84 100644
--- a/net/rxrpc/rxkad.c
+++ b/net/rxrpc/rxkad.c
@@ -664,7 +664,8 @@ static int rxkad_issue_challenge(struct rxrpc_connection *conn)
 
 	ret = kernel_sendmsg(conn->params.local->socket, &msg, iov, 2, len);
 	if (ret < 0) {
-		_debug("sendmsg failed: %d", ret);
+		trace_rxrpc_tx_fail(conn->debug_id, serial, ret,
+				    rxrpc_tx_fail_conn_challenge);
 		return -EAGAIN;
 	}
 
@@ -719,7 +720,8 @@ static int rxkad_send_response(struct rxrpc_connection *conn,
 
 	ret = kernel_sendmsg(conn->params.local->socket, &msg, iov, 3, len);
 	if (ret < 0) {
-		_debug("sendmsg failed: %d", ret);
+		trace_rxrpc_tx_fail(conn->debug_id, serial, ret,
+				    rxrpc_tx_fail_conn_response);
 		return -EAGAIN;
 	}
 

Re: [PATCH net 0/5] rxrpc: Fixes

[David Miller]

From: David Howells <dhowells@redhat.com>
Date: Thu, 10 May 2018 23:45:17 +0100

> Here are three fixes for AF_RXRPC and two tracepoints that were useful for
> finding them:
 ...
> The patches are tagged here:
> 
> 	git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs.git
> 	rxrpc-fixes-20180510

Pulled, thanks David.