Nikolay Aleksandrov 18041e3174 vrf: vrf_master_ifindex_rcu is not always called with rcu read lock ... While running net-next I hit this: [ 634.073119] =============================== [ 634.073150] [ INFO: suspicious RCU usage. ] [ 634.073182] 4.2.0-rc6+ #45 Not tainted [ 634.073213] ------------------------------- [ 634.073244] include/net/vrf.h:38 suspicious rcu_dereference_check() usage! [ 634.073274] other info that might help us debug this: [ 634.073307] rcu_scheduler_active = 1, debug_locks = 1 [ 634.073338] 2 locks held by swapper/0/0: [ 634.073369] #0: (((&n->timer))){+.-...}, at: [<ffffffff8112bc35>] call_timer_fn+0x5/0x480 [ 634.073412] #1: (slock-AF_INET){+.-...}, at: [<ffffffff8174f0f5>] icmp_send+0x155/0x5f0 [ 634.073450] stack backtrace: [ 634.073483] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.2.0-rc6+ #45 [ 634.073514] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006 [ 634.073545] 0000000000000000 0593ba8242d9ace4 ffff88002fc03b48 ffffffff81803f1b [ 634.073612] 0000000000000000 ffffffff81e12500 ffff88002fc03b78 ffffffff811003c5 [ 634.073642] 0000000000000000 ffff88002ec4e600 ffffffff81f00f80 ffff88002fc03cf0 [ 634.073669] Call Trace: [ 634.073694] <IRQ> [<ffffffff81803f1b>] dump_stack+0x4c/0x65 [ 634.073728] [<ffffffff811003c5>] lockdep_rcu_suspicious+0xc5/0x100 [ 634.073763] [<ffffffff8174eb56>] icmp_route_lookup+0x176/0x5c0 [ 634.073793] [<ffffffff8174f2fb>] ? icmp_send+0x35b/0x5f0 [ 634.073818] [<ffffffff8174f274>] ? icmp_send+0x2d4/0x5f0 [ 634.073844] [<ffffffff8174f3ce>] icmp_send+0x42e/0x5f0 [ 634.073873] [<ffffffff8170b662>] ipv4_link_failure+0x22/0xa0 [ 634.073899] [<ffffffff8174bdda>] arp_error_report+0x3a/0x80 [ 634.073926] [<ffffffff816d6100>] ? neigh_lookup+0x2c0/0x2c0 [ 634.073952] [<ffffffff816d396e>] neigh_invalidate+0x8e/0x110 [ 634.073984] [<ffffffff816d62ae>] neigh_timer_handler+0x1ae/0x290 [ 634.074013] [<ffffffff816d6100>] ? neigh_lookup+0x2c0/0x2c0 [ 634.074013] [<ffffffff8112bce3>] call_timer_fn+0xb3/0x480 [ 634.074013] [<ffffffff8112bc35>] ? call_timer_fn+0x5/0x480 [ 634.074013] [<ffffffff816d6100>] ? neigh_lookup+0x2c0/0x2c0 [ 634.074013] [<ffffffff8112c2bc>] run_timer_softirq+0x20c/0x430 [ 634.074013] [<ffffffff810af50e>] __do_softirq+0xde/0x630 [ 634.074013] [<ffffffff810afc97>] irq_exit+0x117/0x120 [ 634.074013] [<ffffffff81810976>] smp_apic_timer_interrupt+0x46/0x60 [ 634.074013] [<ffffffff8180e950>] apic_timer_interrupt+0x70/0x80 [ 634.074013] <EOI> [<ffffffff8106b9d6>] ? native_safe_halt+0x6/0x10 [ 634.074013] [<ffffffff81101d8d>] ? trace_hardirqs_on+0xd/0x10 [ 634.074013] [<ffffffff81027d43>] default_idle+0x23/0x200 [ 634.074013] [<ffffffff8102852f>] arch_cpu_idle+0xf/0x20 [ 634.074013] [<ffffffff810f89ba>] default_idle_call+0x2a/0x40 [ 634.074013] [<ffffffff810f8dcc>] cpu_startup_entry+0x39c/0x4c0 [ 634.074013] [<ffffffff817f9cad>] rest_init+0x13d/0x150 [ 634.074013] [<ffffffff81f69038>] start_kernel+0x4a8/0x4c9 [ 634.074013] [<ffffffff81f68120>] ? early_idt_handler_array+0x120/0x120 [ 634.074013] [<ffffffff81f68339>] x86_64_start_reservations+0x2a/0x2c [ 634.074013] [<ffffffff81f68485>] x86_64_start_kernel+0x14a/0x16d It would seem vrf_master_ifindex_rcu() can be called without RCU held in other contexts as well so introduce a new helper which acquires rcu and returns the ifindex. Also add curly braces around both the "if" and "else" parts as per the style guide. Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>		2015-08-19 22:13:20 -07:00
..
9p	9p: switch p9_client_read() to passing struct iov_iter *	2015-04-11 22:28:27 -04:00
bluetooth	Bluetooth: add hci_connect_le_scan	2015-08-10 21:36:13 +02:00
caif	caif: fix a signedness bug in cfpkt_iterate()	2015-02-20 17:35:14 -05:00
irda
iucv
netfilter	netfilter: fix netns dependencies with conntrack templates	2015-07-20 14:58:19 +02:00
netns	Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next	2015-08-04 23:57:45 -07:00
nfc	NFC: nci: add generic uart support	2015-06-11 23:37:37 +02:00
phonet
sctp	sctp: fix ASCONF list handling	2015-06-14 12:55:49 -07:00
tc_act	net_sched: act_mirred: remove spinlock in fast path	2015-07-08 13:50:42 -07:00
6lowpan.h	6lowpan: add generic 6lowpan netdev private data	2015-08-11 22:05:36 +02:00
act_api.h	Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net	2015-07-31 23:52:20 -07:00
addrconf.h	ipv6: change ipv6_stub_impl.ipv6_dst_lookup to take net argument	2015-07-31 15:21:30 -07:00
af_ieee802154.h
af_rxrpc.h
af_unix.h	net/unix: support SCM_SECURITY for stream sockets	2015-06-10 22:49:20 -07:00
af_vsock.h	net: Pass kern from net_proto_family.create to sk_alloc	2015-05-11 10:50:17 -04:00
ah.h
arp.h	neigh: Factor out ___neigh_lookup_noref	2015-03-04 00:23:23 -05:00
atmclip.h
ax25.h	ax25: Stop using sock->sk_protinfo.	2015-06-28 16:55:44 -07:00
ax88796.h
bond_3ad.h	bonding: Implement port churn-machine (AD standard 43.4.17).	2015-02-24 16:05:48 -05:00
bond_alb.h
bond_options.h	bonding: convert num_grat_arp to the new bonding option API	2015-07-27 01:05:24 -07:00
bonding.h	bonding: Implement user key part of port_key in an AD system.	2015-05-11 10:59:32 -04:00
busy_poll.h
cfg80211-wext.h
cfg80211.h	Merge branch 'mac80211' into mac80211-next	2015-07-17 15:39:41 +02:00
cfg802154.h	ieee802154: add ack request default handling	2015-08-10 20:43:06 +02:00
checksum.h	net: Add inet_proto_csum_replace_by_diff utility function	2015-08-17 21:33:06 -07:00
cipso_ipv4.h
cls_cgroup.h	cls_cgroup: factor out classid retrieval	2015-07-20 12:41:30 -07:00
codel.h	Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net	2015-05-13 14:31:43 -04:00
compat.h	net: switch importing msghdr from userland to {compat_,}import_iovec()	2015-04-09 00:02:26 -04:00
datalink.h
dcbevent.h
dcbnl.h	net/dcb: Add IEEE QCN attribute	2015-03-06 21:50:02 -05:00
dn_dev.h
dn_fib.h
dn_neigh.h	netfilter: Pass socket pointer down through okfn().	2015-04-07 15:25:55 -04:00
dn_nsp.h
dn_route.h
dn.h
dsa.h	net: dsa: Add dsa_is_dsa_port() helper	2015-08-18 14:17:21 -07:00
dsfield.h
dst_metadata.h	bpf: add helpers to access tunnel metadata	2015-07-31 15:20:22 -07:00
dst_ops.h	net: Remove protocol from struct dst_ops	2015-03-09 16:06:10 -04:00
dst.h	dst: Metadata destinations	2015-07-21 10:39:05 -07:00
esp.h
ethoc.h
fib_rules.h	fib: Add fib rule match on tunnel id	2015-07-21 10:39:06 -07:00
firewire.h
flow_dissector.h	mpls: Add MPLS entropy label in flow_keys	2015-06-04 15:44:31 -07:00
flow.h	net: Use VRF device index for lookups on TX	2015-08-13 22:43:20 -07:00
flowcache.h
fou.h
garp.h
gen_stats.h
genetlink.h	net: Introduce possible_net_t	2015-03-12 14:39:40 -04:00
geneve.h	geneve: move definition of geneve_hdr() to geneve.h	2015-05-13 15:59:13 -04:00
gre.h	gre: Remove support for sharing GRE protocol hook.	2015-08-10 14:03:54 -07:00
gro_cells.h
gue.h
icmp.h
ieee80211_radiotap.h
ieee802154_netdev.h	mac802154: cleanup llsec param flags	2015-06-12 11:42:29 +02:00
if_inet6.h	ipv6: do retries on stable privacy addresses	2015-03-23 22:12:09 -04:00
inet6_connection_sock.h	inet: get rid of central tcp/dccp listener timer	2015-03-20 12:40:25 -04:00
inet6_hashtables.h	ipv6: get rid of __inet6_hash()	2015-03-18 22:00:35 -04:00
inet_common.h	net: Modify sk_alloc to not reference count the netns of kernel sockets.	2015-05-11 10:50:18 -04:00
inet_connection_sock.h	tcp: fix child sockets to use system default congestion control if not set	2015-05-31 21:49:14 -07:00
inet_ecn.h
inet_frag.h	inet: frags: remove INET_FRAG_EVICTED and use list_evictor for the test	2015-07-26 21:00:15 -07:00
inet_hashtables.h	inet: simplify timewait refcounting	2015-07-09 15:12:20 -07:00
inet_sock.h	inet: add IP_BIND_ADDRESS_NO_PORT to overcome bind(0) limitations	2015-06-06 23:57:12 -07:00
inet_timewait_sock.h	inet: inet_twsk_deschedule factorization	2015-07-09 15:12:20 -07:00
inetpeer.h	tcp: simplify inetpeer_addr_base use	2015-03-31 13:58:35 -04:00
ip6_checksum.h
ip6_fib.h	ipv6: support for fib route lwtunnel encap attributes	2015-07-21 10:39:04 -07:00
ip6_route.h	ipv6: Add rt6_get_cookie() function	2015-05-25 13:25:34 -04:00
ip6_tunnel.h	udp_tunnel: Pass UDP socket down through udp_tunnel{, 6}_xmit_skb().	2015-04-07 15:29:08 -04:00
ip_fib.h	Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net	2015-07-31 23:52:20 -07:00
ip_tunnels.h	ip_gre: Add support to collect tunnel metadata.	2015-08-10 14:03:54 -07:00
ip_vs.h	net: Introduce possible_net_t	2015-03-12 14:39:40 -04:00
ip.h	net: Set sk_txhash from a random number	2015-07-29 22:44:04 -07:00
ipcomp.h
ipconfig.h
ipv6.h	ipv6: Enable auto flow labels by default	2015-07-31 17:07:12 -07:00
ipx.h
iw_handler.h	wext: add checked wrappers for adding events/points to streams	2015-02-28 21:31:12 +01:00
lapb.h
lib80211.h
llc_c_ac.h
llc_c_ev.h
llc_c_st.h
llc_conn.h	net: Pass kern from net_proto_family.create to sk_alloc	2015-05-11 10:50:17 -04:00
llc_if.h
llc_pdu.h
llc_s_ac.h
llc_s_ev.h
llc_s_st.h
llc_sap.h
llc.h
lwtunnel.h	lwtunnel: Fix the sparse warnings in fib_encap_match	2015-08-19 17:37:51 -07:00
mac80211.h	mac80211: remove ieee80211_aes_cmac_calculate_k1_k2()	2015-08-13 11:31:45 +02:00
mac802154.h	mac802154: do not export ieee802154_rx()	2015-07-23 17:10:50 +02:00
mip6.h
mld.h
mpls_iptunnel.h	mpls: ip tunnel support	2015-07-21 10:39:05 -07:00
mpls.h
mrp.h
ndisc.h	neigh: Factor out ___neigh_lookup_noref	2015-03-04 00:23:23 -05:00
neighbour.h	net: add explicit logging and stat for neighbour table overflow	2015-08-10 13:46:21 -07:00
net_namespace.h	net: include missing headers in net/net_namespace.h	2015-06-18 21:14:29 +02:00
net_ratelimit.h
netevent.h
netlabel.h
netlink.h	netlink: implement nla_get_in_addr and nla_get_in6_addr	2015-03-31 13:58:35 -04:00
netprio_cgroup.h
netrom.h
nexthop.h
nl802154.h	ieee802154: add ack request default handling	2015-08-10 20:43:06 +02:00
p8022.h
ping.h	net: Remove iocb argument from sendmsg and recvmsg	2015-03-02 13:06:31 -05:00
pkt_cls.h
pkt_sched.h
protocol.h
psnap.h
raw.h
rawv6.h
red.h
regulatory.h
request_sock.h	tcp: provide SYN headers for passive connections	2015-05-05 16:02:34 -04:00
rose.h
route.h	net: Fix up inet_addr_type checks	2015-08-13 22:43:21 -07:00
rtnetlink.h	openvswitch: Use regular VXLAN net_device device	2015-07-21 10:39:07 -07:00
sch_generic.h	net: sched: extend percpu stats helpers	2015-07-08 13:50:41 -07:00
scm.h
secure_seq.h
slhc_vj.h
snmp.h
sock.h	Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net	2015-07-31 23:52:20 -07:00
Space.h
stp.h
switchdev.h	net: switchdev: support static FDB addresses	2015-08-11 12:03:19 -07:00
tcp_memcontrol.h
tcp_states.h	inet: add TCP_NEW_SYN_RECV state	2015-03-12 22:58:12 -04:00
tcp.h	tcp: do not slow start when cwnd equals ssthresh	2015-07-09 14:22:52 -07:00
timewait_sock.h	inet: remove BUG_ON() in twsk_destructor()	2015-07-09 15:12:20 -07:00
transp_v6.h
tso.h
udp_tunnel.h	udp_tunnel: Pass UDP socket down through udp_tunnel{, 6}_xmit_skb().	2015-04-07 15:29:08 -04:00
udp.h	net: Remove iocb argument from sendmsg and recvmsg	2015-03-02 13:06:31 -05:00
udplite.h
vrf.h	vrf: vrf_master_ifindex_rcu is not always called with rcu read lock	2015-08-19 22:13:20 -07:00
vsock_addr.h
vxlan.h	vxlan: combine VXLAN_FLOWBASED into VXLAN_COLLECT_METADATA	2015-08-07 11:46:34 -07:00
wext.h
wimax.h
x25.h
x25device.h
xfrm.h	xfrm: Add oif to dst lookups	2015-08-11 12:41:35 +02:00