Merge tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Don't destroy user event fields when removal fails

   User event fields are destroyed before the event is removed from
   visibility. But that can fail leaving the still visible event with no
   fields. Move the destroying of the fields to after the event is
   successfully removed from visibility.

 - Initialize function graph state is fork before calling
   copy_exec_state()

   For non-CLONE_VM forks, copy_exec_state() allocates a new
   task_exec_state. If that allocation fails, ftrace_graph_exit_task()
   will free the tasks ret_stack pointer. Since that pointer is still
   using the parent's ret_stack, it mistakenly frees the parent's
   pointer too.

   Call ftrace_graph_init() on the task first which will NULL out the
   new tasks's ret_stack and if the copy fails, it will not free
   anything.

 - Remove FGRAPH_MAX_INDEX

   The macro FGRAPH_MAX_INDEX was added but never used. Remove it.

 - Save ent_size in function graph printing of nested functions

   The function graph tracer needs to look at the next event to see if
   the next event is the return of the current function entry. If it is,
   it prints a single line:

	ktime_get();

   Otherwise it prints it like a nested function:

	tick_nohz_irq_exit() {
	    ktime_get();
	    kcpustat_irq_exit();
	}

   In order to look at the next event, it must save the current event so
   that it has the information to print from it. It saves the event in
   the iterator descriptor called "ent". What it doesn't save is the
   ent_size of the event which is now used to know if the function graph
   arguments are to be printed. The peek doesn't save the size so the
   size used happens to be that of the size of the last event that was
   seen.

   Save the entry event size in the iterator descriptor so that the
   correct size is used.

 - Fix several errors with freeing data in the histogram code

   The histogram code had a lot of leaked or or incorrect accounting
   when failures happen. Correct them.

 - Fix histogram regression of .percent and .graph modifiers

   Up until 6.3 histogram values could have "percent" or "graph"
   modifiers that changed how they were printed. But a change that added
   restricting histograms values from being strings, stack traces and
   other modifiers inadvertently prevented them from using the percent
   and graph modifiers, which were legal use cases for values.

   Put back the percent and graph modifiers.

 - Fix various typos in the comments

 - Set the trace_clock before initializing a histogram with clock
   argument

   The histogram API allows the user to specific which trace clock to
   use via a "clock=" string. The histogram is set up first before the
   clock is checked. If the passed in clock is not valid, it exits
   without fully fixing up the histogram leaving it on the list and a
   use-after-free can trigger.

   Update the clock argument first and if it fails then exit gracefully
   before the histogram trigger is placed on any lists.

 - Restore :mod: trailer after parsing in ftrace_set_clr_event

   The function ftrace_set_clr_event() modifies the parse string and
   needs to put it back to what was passed in. It searches for ":mod:"
   via a strsep() but fails to put back the first ':' in the string.

   Add back the ':' in the passed in string.

 - Take trace_array reference when opening a tracer options file

   The options files are dynamically created and some tracers add their
   own options. When a tracer adds their own list of options, the
   trace_array holding them has an array to hold the list of options for
   each tracer. This array increases in size via a krealloc(), and the
   new entry gets a newly allocated array to hold the options of the new
   tracer being added.

   The element in each entry of the tracer's option array holds a
   pointer back to the trace_array, a pointer to the tracer it is
   associated to, a pointer to the flags of the option.

   The issue is that these arrays are freed when the trace_array is
   freed when its instance it represents is removed from the instances
   directory. There's a race that an open of one of these options files
   can happen when the instance is being removed.

   Add a new helper function to be called by the open function of the
   options file to iterate all existing trace_arrays under a lock and
   find the one that has the given option element in one of it's tracer
   arrays. If found, then update the associated trace_array's reference
   counter to keep it from being freed. If not found, have the open call
   return -ENODEV.

 - Disable interrupts when acquiring the lock in rb_wake_up_waiters()

   The function rb_wake_up_waiters() assumes it will be called in
   interrupt context and does not disable irqs when taking
   cpu_buffer->reader_lock, which can be called in hard interrupt
   context. The issue is in PREEMPT_RT, this function is called in
   thread context leaving this lock open to a deadlock.

   Take the lock with interrupts disabled.

 - Use rcu_assign_pointer() for tmp_ops filter hash

   The tmp_ops used in update_ftrace_direct_mod() assigns its
   filter_hash field directly, but that field is annotated as __rcu and
   sparse complains. Assign it with rcu_assign_pointer()

 - Fix use-after-free in enable_trigger_private_data_free()

   The trace_event_call is accessed through the event_trigger_data's
   trace_event_file pointer to put the trace_event_call on freeing. The
   issue is that the trace_event_file data may have been freed already
   causing a use-after-free. Add a field to the event_trigger_data that
   points directly to the trace_event_call so that it can decrement its
   reference directly without needing to go through the
   trace_event_file.

 - Fix accounting of buffer data remote headers

   trace_buffer_desc_size() and trace_remote_alloc_buffer() undercount
   the number of pages is needed for the asked for size as it doesn't
   take into account the meta data on each page. Add a helper function
   to do the calculation properly and use that in these functions.

 - Catch nr_page_va overflow in ring_buffer_desc sizing

   The number of pages per remote ring buffer is capped by
   ring_buffer_desc::nr_page_va (32 bits). A buffer_size large enough to
   overflow that field would silently allocate a descriptor smaller than
   what was asked for.

 - Do not resize the subbuf order if any per_cpu buffer is disabled

   The mmapping of ring buffers disables resizing the subbuffers, but it
   is done per-cpu whereas the subbuf size change is done for all the
   per_cpu buffers under the buffer->mutex. It could change the size of
   some while the mapping is happening on others. Have the resize of the
   subbuf order check all the per_cpu buffers under the lock to see if
   any of them is disabled before starting and causing an inconsistency
   between buffers that are being mapped.

* tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (25 commits)
  ring-buffer: Check resize_disabled before publishing the new subbuf order
  tracing/remotes: Catch nr_page_va overflow in ring_buffer_desc sizing
  tracing/remotes: Account for ring buffer page header in size calculation
  tracing: Don't dereference trace_event_file in deferred trigger free
  ftrace: Use rcu_assign_pointer() for tmp_ops filter hash
  ring-buffer: Acquire the lock with irqsave in rb_wake_up_waiters()
  tracing: Take trace_array reference when opening a tracer options file
  tracing: Fix ring_buffer_read_page_size() kernel-doc
  tracing: Restore :mod: trailer after parsing in ftrace_set_clr_event()
  tracing: Fix memory corruption from a "STACKTRACE" histogram key
  tracing: Fix memory corruption from the histogram stacktrace modifier
  tracing: Undo the registration when enabling the histogram trigger fails
  tracing: Take the reference before publishing the named histogram trigger
  tracing: Set the trace clock before registering the histogram trigger
  tracing: Fix typo "preceeded" in comment
  tracing: Fix typo "availabe" in comment
  tracing: Let histogram values keep the percent and graph modifiers
  tracing: Keep the entry count when the histogram stats allocation fails
  tracing: Free histogram the field rejected for a bad modifier
  tracing: Free histogram the var ref when its initialization fails
  ...

1 files changed, 583 insertions, 0 deletions

diff --git a/net/rxrpc/io_thread.c b/net/rxrpc/io_thread.c
new file mode 100644
index 000000000..dc5184a2f
--- /dev/null
+++ b/net/rxrpc/io_thread.c
@@ -0,0 +1,583 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/* RxRPC packet reception
+ *
+ * Copyright (C) 2007, 2016, 2022 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include "ar-internal.h"
+
+static int rxrpc_input_packet_on_conn(struct rxrpc_connection *conn,
+				      struct sockaddr_rxrpc *peer_srx,
+				      struct sk_buff *skb);
+
+/*
+ * handle data received on the local endpoint
+ * - may be called in interrupt context
+ *
+ * [!] Note that as this is called from the encap_rcv hook, the socket is not
+ * held locked by the caller and nothing prevents sk_user_data on the UDP from
+ * being cleared in the middle of processing this function.
+ *
+ * Called with the RCU read lock held from the IP layer via UDP.
+ */
+int rxrpc_encap_rcv(struct sock *udp_sk, struct sk_buff *skb)
+{
+	struct sk_buff_head *rx_queue;
+	struct rxrpc_local *local = rcu_dereference_sk_user_data(udp_sk);
+	struct task_struct *io_thread;
+
+	if (unlikely(!local)) {
+		kfree_skb(skb);
+		return 0;
+	}
+	io_thread = READ_ONCE(local->io_thread);
+	if (!io_thread) {
+		kfree_skb(skb);
+		return 0;
+	}
+	if (skb->tstamp == 0)
+		skb->tstamp = ktime_get_real();
+
+	skb->mark = RXRPC_SKB_MARK_PACKET;
+	rxrpc_new_skb(skb, rxrpc_skb_new_encap_rcv);
+	rx_queue = &local->rx_queue;
+#ifdef CONFIG_AF_RXRPC_INJECT_RX_DELAY
+	if (rxrpc_inject_rx_delay ||
+	    !skb_queue_empty(&local->rx_delay_queue)) {
+		skb->tstamp = ktime_add_ms(skb->tstamp, rxrpc_inject_rx_delay);
+		rx_queue = &local->rx_delay_queue;
+	}
+#endif
+
+	skb_queue_tail(rx_queue, skb);
+	wake_up_process(io_thread);
+	return 0;
+}
+
+/*
+ * Handle an error received on the local endpoint.
+ */
+void rxrpc_error_report(struct sock *sk)
+{
+	struct rxrpc_local *local;
+	struct sk_buff *skb;
+
+	rcu_read_lock();
+	local = rcu_dereference_sk_user_data(sk);
+	if (unlikely(!local)) {
+		rcu_read_unlock();
+		return;
+	}
+
+	while ((skb = skb_dequeue(&sk->sk_error_queue))) {
+		skb->mark = RXRPC_SKB_MARK_ERROR;
+		rxrpc_new_skb(skb, rxrpc_skb_new_error_report);
+		skb_queue_tail(&local->rx_queue, skb);
+	}
+
+	rxrpc_wake_up_io_thread(local);
+	rcu_read_unlock();
+}
+
+/*
+ * Directly produce an abort from a packet.
+ */
+bool rxrpc_direct_abort(struct sk_buff *skb, enum rxrpc_abort_reason why,
+			s32 abort_code, int err)
+{
+	struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
+
+	trace_rxrpc_abort(0, why, sp->hdr.cid, sp->hdr.callNumber, sp->hdr.seq,
+			  abort_code, err);
+	skb->mark = RXRPC_SKB_MARK_REJECT_ABORT;
+	skb->priority = abort_code;
+	return false;
+}
+
+/*
+ * Directly produce a connection abort from a packet.
+ */
+bool rxrpc_direct_conn_abort(struct sk_buff *skb, enum rxrpc_abort_reason why,
+			     s32 abort_code, int err)
+{
+	struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
+
+	trace_rxrpc_abort(0, why, sp->hdr.cid, 0, sp->hdr.seq, abort_code, err);
+	skb->mark = RXRPC_SKB_MARK_REJECT_CONN_ABORT;
+	skb->priority = abort_code;
+	return false;
+}
+
+static bool rxrpc_bad_message(struct sk_buff *skb, enum rxrpc_abort_reason why)
+{
+	return rxrpc_direct_abort(skb, why, RX_PROTOCOL_ERROR, -EBADMSG);
+}
+
+#define just_discard true
+
+/*
+ * Process event packets targeted at a local endpoint.
+ */
+static bool rxrpc_input_version(struct rxrpc_local *local, struct sk_buff *skb)
+{
+	struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
+	char v;
+
+	_enter("");
+
+	rxrpc_see_skb(skb, rxrpc_skb_see_version);
+	if (skb_copy_bits(skb, sizeof(struct rxrpc_wire_header), &v, 1) >= 0) {
+		if (v == 0)
+			rxrpc_send_version_request(local, &sp->hdr, skb);
+	}
+
+	return true;
+}
+
+/*
+ * Extract the wire header from a packet and translate the byte order.
+ */
+static bool rxrpc_extract_header(struct rxrpc_skb_priv *sp,
+				 struct sk_buff *skb)
+{
+	struct rxrpc_wire_header whdr;
+	struct rxrpc_ackpacket ack;
+
+	/* dig out the RxRPC connection details */
+	if (skb_copy_bits(skb, 0, &whdr, sizeof(whdr)) < 0)
+		return rxrpc_bad_message(skb, rxrpc_badmsg_short_hdr);
+
+	memset(sp, 0, sizeof(*sp));
+	sp->hdr.epoch		= ntohl(whdr.epoch);
+	sp->hdr.cid		= ntohl(whdr.cid);
+	sp->hdr.callNumber	= ntohl(whdr.callNumber);
+	sp->hdr.seq		= ntohl(whdr.seq);
+	sp->hdr.serial		= ntohl(whdr.serial);
+	sp->hdr.flags		= whdr.flags;
+	sp->hdr.type		= whdr.type;
+	sp->hdr.userStatus	= whdr.userStatus;
+	sp->hdr.securityIndex	= whdr.securityIndex;
+	sp->hdr._rsvd		= ntohs(whdr._rsvd);
+	sp->hdr.serviceId	= ntohs(whdr.serviceId);
+
+	if (sp->hdr.type == RXRPC_PACKET_TYPE_ACK) {
+		if (skb_copy_bits(skb, sizeof(whdr), &ack, sizeof(ack)) < 0)
+			return rxrpc_bad_message(skb, rxrpc_badmsg_short_ack);
+		sp->ack.first_ack	= ntohl(ack.firstPacket);
+		sp->ack.prev_ack	= ntohl(ack.previousPacket);
+		sp->ack.acked_serial	= ntohl(ack.serial);
+		sp->ack.reason		= ack.reason;
+		sp->ack.nr_acks		= ack.nAcks;
+	}
+	return true;
+}
+
+/*
+ * Extract the abort code from an ABORT packet and stash it in skb->priority.
+ */
+static bool rxrpc_extract_abort(struct sk_buff *skb)
+{
+	__be32 wtmp;
+
+	if (skb_copy_bits(skb, sizeof(struct rxrpc_wire_header),
+			  &wtmp, sizeof(wtmp)) < 0)
+		return false;
+	skb->priority = ntohl(wtmp);
+	return true;
+}
+
+/*
+ * Process packets received on the local endpoint
+ */
+static bool rxrpc_input_packet(struct rxrpc_local *local, struct sk_buff *skb)
+{
+	struct rxrpc_connection *conn;
+	struct sockaddr_rxrpc peer_srx;
+	struct rxrpc_skb_priv *sp;
+	struct rxrpc_peer *peer = NULL;
+	bool ret = false;
+
+	skb_pull(skb, sizeof(struct udphdr));
+
+	sp = rxrpc_skb(skb);
+
+	/* dig out the RxRPC connection details */
+	if (!rxrpc_extract_header(sp, skb))
+		return just_discard;
+
+	if (IS_ENABLED(CONFIG_AF_RXRPC_INJECT_LOSS)) {
+		static int lose;
+		if ((lose++ & 7) == 7) {
+			trace_rxrpc_rx_lose(sp);
+			return just_discard;
+		}
+	}
+
+	trace_rxrpc_rx_packet(sp);
+
+	switch (sp->hdr.type) {
+	case RXRPC_PACKET_TYPE_VERSION:
+		if (rxrpc_to_client(sp))
+			return just_discard;
+		return rxrpc_input_version(local, skb);
+
+	case RXRPC_PACKET_TYPE_BUSY:
+		if (rxrpc_to_server(sp))
+			return just_discard;
+		fallthrough;
+	case RXRPC_PACKET_TYPE_ACK:
+	case RXRPC_PACKET_TYPE_ACKALL:
+		if (sp->hdr.callNumber == 0)
+			return rxrpc_bad_message(skb, rxrpc_badmsg_zero_call);
+		break;
+	case RXRPC_PACKET_TYPE_ABORT:
+		if (!rxrpc_extract_abort(skb))
+			return just_discard; /* Just discard if malformed */
+		break;
+
+	case RXRPC_PACKET_TYPE_DATA:
+		if (sp->hdr.callNumber == 0)
+			return rxrpc_bad_message(skb, rxrpc_badmsg_zero_call);
+		if (sp->hdr.seq == 0)
+			return rxrpc_bad_message(skb, rxrpc_badmsg_zero_seq);
+		break;
+
+	case RXRPC_PACKET_TYPE_CHALLENGE:
+		if (rxrpc_to_server(sp))
+			return just_discard;
+		break;
+	case RXRPC_PACKET_TYPE_RESPONSE:
+		if (rxrpc_to_client(sp))
+			return just_discard;
+		break;
+
+		/* Packet types 9-11 should just be ignored. */
+	case RXRPC_PACKET_TYPE_PARAMS:
+	case RXRPC_PACKET_TYPE_10:
+	case RXRPC_PACKET_TYPE_11:
+		return just_discard;
+
+	default:
+		return rxrpc_bad_message(skb, rxrpc_badmsg_unsupported_packet);
+	}
+
+	if (sp->hdr.serviceId == 0)
+		return rxrpc_bad_message(skb, rxrpc_badmsg_zero_service);
+
+	if (WARN_ON_ONCE(rxrpc_extract_addr_from_skb(&peer_srx, skb) < 0))
+		return just_discard; /* Unsupported address type. */
+
+	if (peer_srx.transport.family != local->srx.transport.family &&
+	    (peer_srx.transport.family == AF_INET &&
+	     local->srx.transport.family != AF_INET6)) {
+		pr_warn_ratelimited("AF_RXRPC: Protocol mismatch %u not %u\n",
+				    peer_srx.transport.family,
+				    local->srx.transport.family);
+		return just_discard; /* Wrong address type. */
+	}
+
+	if (rxrpc_to_client(sp)) {
+		rcu_read_lock();
+		conn = rxrpc_find_client_connection_rcu(local, &peer_srx, skb);
+		conn = rxrpc_get_connection_maybe(conn, rxrpc_conn_get_call_input);
+		rcu_read_unlock();
+		if (!conn)
+			return rxrpc_protocol_error(skb, rxrpc_eproto_no_client_conn);
+
+		ret = rxrpc_input_packet_on_conn(conn, &peer_srx, skb);
+		rxrpc_put_connection(conn, rxrpc_conn_put_call_input);
+		return ret;
+	}
+
+	/* We need to look up service connections by the full protocol
+	 * parameter set.  We look up the peer first as an intermediate step
+	 * and then the connection from the peer's tree.
+	 */
+	rcu_read_lock();
+
+	peer = rxrpc_lookup_peer_rcu(local, &peer_srx);
+	if (!peer) {
+		rcu_read_unlock();
+		return rxrpc_new_incoming_call(local, NULL, NULL, &peer_srx, skb);
+	}
+
+	conn = rxrpc_find_service_conn_rcu(peer, skb);
+	conn = rxrpc_get_connection_maybe(conn, rxrpc_conn_get_call_input);
+	if (conn) {
+		rcu_read_unlock();
+		ret = rxrpc_input_packet_on_conn(conn, &peer_srx, skb);
+		rxrpc_put_connection(conn, rxrpc_conn_put_call_input);
+		return ret;
+	}
+
+	peer = rxrpc_get_peer_maybe(peer, rxrpc_peer_get_input);
+	rcu_read_unlock();
+
+	ret = rxrpc_new_incoming_call(local, peer, NULL, &peer_srx, skb);
+	rxrpc_put_peer(peer, rxrpc_peer_put_input);
+	return ret;
+}
+
+/*
+ * Deal with a packet that's associated with an extant connection.
+ */
+static int rxrpc_input_packet_on_conn(struct rxrpc_connection *conn,
+				      struct sockaddr_rxrpc *peer_srx,
+				      struct sk_buff *skb)
+{
+	struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
+	struct rxrpc_channel *chan;
+	struct rxrpc_call *call = NULL;
+	unsigned int channel;
+
+	if (sp->hdr.securityIndex != conn->security_ix)
+		return rxrpc_direct_abort(skb, rxrpc_eproto_wrong_security,
+					  RXKADINCONSISTENCY, -EBADMSG);
+
+	if (sp->hdr.serviceId != conn->service_id) {
+		int old_id;
+
+		if (!test_bit(RXRPC_CONN_PROBING_FOR_UPGRADE, &conn->flags))
+			return rxrpc_protocol_error(skb, rxrpc_eproto_reupgrade);
+
+		old_id = cmpxchg(&conn->service_id, conn->orig_service_id,
+				 sp->hdr.serviceId);
+		if (old_id != conn->orig_service_id &&
+		    old_id != sp->hdr.serviceId)
+			return rxrpc_protocol_error(skb, rxrpc_eproto_bad_upgrade);
+	}
+
+	if (after(sp->hdr.serial, conn->hi_serial))
+		conn->hi_serial = sp->hdr.serial;
+
+	/* It's a connection-level packet if the call number is 0. */
+	if (sp->hdr.callNumber == 0)
+		return rxrpc_input_conn_packet(conn, skb);
+
+	/* Deal with path MTU discovery probing. */
+	if (sp->hdr.type == RXRPC_PACKET_TYPE_ACK &&
+	    conn->pmtud_probe &&
+	    after_eq(sp->ack.acked_serial, conn->pmtud_probe))
+		rxrpc_input_probe_for_pmtud(conn, sp->ack.acked_serial, false);
+
+	/* Call-bound packets are routed by connection channel. */
+	channel = sp->hdr.cid & RXRPC_CHANNELMASK;
+	chan = &conn->channels[channel];
+
+	/* Ignore really old calls */
+	if (sp->hdr.callNumber < chan->last_call)
+		return just_discard;
+
+	if (sp->hdr.callNumber == chan->last_call) {
+		if (chan->call ||
+		    sp->hdr.type == RXRPC_PACKET_TYPE_ABORT)
+			return just_discard;
+
+		/* For the previous service call, if completed successfully, we
+		 * discard all further packets.
+		 */
+		if (rxrpc_conn_is_service(conn) &&
+		    chan->last_type == RXRPC_PACKET_TYPE_ACK)
+			return just_discard;
+
+		/* But otherwise we need to retransmit the final packet from
+		 * data cached in the connection record.
+		 */
+		if (sp->hdr.type == RXRPC_PACKET_TYPE_DATA)
+			trace_rxrpc_rx_data(chan->call_debug_id,
+					    sp->hdr.seq,
+					    sp->hdr.serial,
+					    sp->hdr.flags);
+		rxrpc_conn_retransmit_call(conn, skb, channel);
+		return just_discard;
+	}
+
+	call = rxrpc_try_get_call(chan->call, rxrpc_call_get_input);
+
+	if (sp->hdr.callNumber > chan->call_id) {
+		if (rxrpc_to_client(sp)) {
+			if (call)
+				rxrpc_put_call(call, rxrpc_call_put_input);
+			return rxrpc_protocol_error(skb,
+						    rxrpc_eproto_unexpected_implicit_end);
+		}
+
+		if (call) {
+			rxrpc_implicit_end_call(call, skb);
+			rxrpc_put_call(call, rxrpc_call_put_input);
+			call = NULL;
+		}
+	}
+
+	if (!call) {
+		if (rxrpc_to_client(sp))
+			return rxrpc_protocol_error(skb, rxrpc_eproto_no_client_call);
+		return rxrpc_new_incoming_call(conn->local, conn->peer, conn,
+					       peer_srx, skb);
+	}
+
+	rxrpc_queue_rx_call_packet(call, skb);
+	rxrpc_put_call(call, rxrpc_call_put_input);
+	return true;
+}
+
+/*
+ * I/O and event handling thread.
+ */
+int rxrpc_io_thread(void *data)
+{
+	struct rxrpc_connection *conn;
+	struct sk_buff_head rx_queue;
+	struct rxrpc_local *local = data;
+	struct rxrpc_call *call;
+	struct sk_buff *skb;
+#ifdef CONFIG_AF_RXRPC_INJECT_RX_DELAY
+	ktime_t now;
+#endif
+	bool should_stop;
+	LIST_HEAD(conn_attend_q);
+	LIST_HEAD(call_attend_q);
+
+	complete(&local->io_thread_ready);
+
+	skb_queue_head_init(&rx_queue);
+
+	set_user_nice(current, MIN_NICE);
+
+	for (;;) {
+		rxrpc_inc_stat(local->rxnet, stat_io_loop);
+
+		/* Inject a delay into packets if requested. */
+#ifdef CONFIG_AF_RXRPC_INJECT_RX_DELAY
+		now = ktime_get_real();
+		while ((skb = skb_peek(&local->rx_delay_queue))) {
+			if (ktime_before(now, skb->tstamp))
+				break;
+			skb = skb_dequeue(&local->rx_delay_queue);
+			skb_queue_tail(&local->rx_queue, skb);
+		}
+#endif
+
+		if (!skb_queue_empty(&local->rx_queue)) {
+			spin_lock_irq(&local->rx_queue.lock);
+			skb_queue_splice_tail_init(&local->rx_queue, &rx_queue);
+			spin_unlock_irq(&local->rx_queue.lock);
+			trace_rxrpc_iothread_rx(local, skb_queue_len(&rx_queue));
+		}
+
+		/* Distribute packets and errors. */
+		while ((skb = __skb_dequeue(&rx_queue))) {
+			struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
+			switch (skb->mark) {
+			case RXRPC_SKB_MARK_PACKET:
+				skb->priority = 0;
+				if (!rxrpc_input_packet(local, skb))
+					rxrpc_reject_packet(local, skb);
+				trace_rxrpc_rx_done(skb->mark, skb->priority);
+				rxrpc_free_skb(skb, rxrpc_skb_put_input);
+				break;
+			case RXRPC_SKB_MARK_ERROR:
+				rxrpc_input_error(local, skb);
+				rxrpc_free_skb(skb, rxrpc_skb_put_error_report);
+				break;
+			case RXRPC_SKB_MARK_SERVICE_CONN_SECURED:
+				rxrpc_input_conn_event(sp->poke_conn, skb);
+				rxrpc_put_connection(sp->poke_conn, rxrpc_conn_put_poke);
+				rxrpc_free_skb(skb, rxrpc_skb_put_conn_secured);
+				break;
+			default:
+				WARN_ON_ONCE(1);
+				rxrpc_free_skb(skb, rxrpc_skb_put_unknown);
+				break;
+			}
+		}
+
+		/* Deal with connections that want immediate attention. */
+		if (!list_empty_careful(&local->conn_attend_q)) {
+			spin_lock_irq(&local->lock);
+			list_splice_tail_init(&local->conn_attend_q, &conn_attend_q);
+			spin_unlock_irq(&local->lock);
+		}
+
+		while ((conn = list_first_entry_or_null(&conn_attend_q,
+							struct rxrpc_connection,
+							attend_link))) {
+			spin_lock_irq(&local->lock);
+			list_del_init(&conn->attend_link);
+			spin_unlock_irq(&local->lock);
+			rxrpc_input_conn_event(conn, NULL);
+			rxrpc_put_connection(conn, rxrpc_conn_put_poke);
+		}
+
+		if (test_and_clear_bit(RXRPC_CLIENT_CONN_REAP_TIMER,
+				       &local->client_conn_flags))
+			rxrpc_discard_expired_client_conns(local);
+
+		/* Deal with calls that want immediate attention. */
+		spin_lock_irq(&local->lock);
+		list_splice_tail_init(&local->call_attend_q, &call_attend_q);
+		spin_unlock_irq(&local->lock);
+
+		while ((call = list_first_entry_or_null(&call_attend_q,
+							struct rxrpc_call,
+							attend_link))) {
+			spin_lock_irq(&local->lock);
+			list_del_init(&call->attend_link);
+			spin_unlock_irq(&local->lock);
+			trace_rxrpc_call_poked(call);
+			rxrpc_input_call_event(call);
+			rxrpc_put_call(call, rxrpc_call_put_poke);
+		}
+
+		if (!list_empty(&local->new_client_calls))
+			rxrpc_connect_client_calls(local);
+
+		set_current_state(TASK_INTERRUPTIBLE);
+		should_stop = kthread_should_stop();
+		if (!skb_queue_empty(&local->rx_queue) ||
+		    !list_empty(&local->call_attend_q) ||
+		    !list_empty(&local->conn_attend_q) ||
+		    !list_empty(&local->new_client_calls) ||
+		    test_bit(RXRPC_CLIENT_CONN_REAP_TIMER,
+			     &local->client_conn_flags)) {
+			__set_current_state(TASK_RUNNING);
+			continue;
+		}
+
+		if (should_stop)
+			break;
+
+#ifdef CONFIG_AF_RXRPC_INJECT_RX_DELAY
+		skb = skb_peek(&local->rx_delay_queue);
+		if (skb) {
+			unsigned long timeout;
+			ktime_t tstamp = skb->tstamp;
+			ktime_t now = ktime_get_real();
+			s64 delay_ns = ktime_to_ns(ktime_sub(tstamp, now));
+
+			if (delay_ns <= 0) {
+				__set_current_state(TASK_RUNNING);
+				continue;
+			}
+
+			timeout = nsecs_to_jiffies(delay_ns);
+			timeout = umax(timeout, 1);
+			schedule_timeout(timeout);
+			__set_current_state(TASK_RUNNING);
+			continue;
+		}
+#endif
+
+		schedule();
+	}
+
+	__set_current_state(TASK_RUNNING);
+	rxrpc_see_local(local, rxrpc_local_stop);
+	rxrpc_destroy_local(local);
+	WRITE_ONCE(local->io_thread, NULL);
+	rxrpc_see_local(local, rxrpc_local_stopped);
+	return 0;
+}