BMC/Intel-BMC/linux.git/include/net/ip6_tunnel.h, branch dev-4.3

ip_tunnel: disable preemption when updating per-cpu tstats

2015-12-15T05:40:59+00:00

[ Upstream commit b4fe85f9c9146f60457e9512fb6055e69e6a7a65 ] Drivers like vxlan use the recently introduced udp_tunnel_xmit_skb/udp_tunnel6_xmit_skb APIs. udp_tunnel6_xmit_skb makes use of ip6tunnel_xmit, and ip6tunnel_xmit, after sending the packet, updates the struct stats using the usual u64_stats_update_begin/end calls on this_cpu_ptr(dev->tstats). udp_tunnel_xmit_skb makes use of iptunnel_xmit, which doesn't touch tstats, so drivers like vxlan, immediately after, call iptunnel_xmit_stats, which does the same thing - calls u64_stats_update_begin/end on this_cpu_ptr(dev->tstats). While vxlan is probably fine (I don't know?), calling a similar function from, say, an unbound workqueue, on a fully preemptable kernel causes real issues: [ 188.434537] BUG: using smp_processor_id() in preemptible [00000000] code: kworker/u8:0/6 [ 188.435579] caller is debug_smp_processor_id+0x17/0x20 [ 188.435583] CPU: 0 PID: 6 Comm: kworker/u8:0 Not tainted 4.2.6 #2 [ 188.435607] Call Trace: [ 188.435611] [] dump_stack+0x4f/0x7b [ 188.435615] [] check_preemption_disabled+0x19d/0x1c0 [ 188.435619] [] debug_smp_processor_id+0x17/0x20 The solution would be to protect the whole this_cpu_ptr(dev->tstats)/u64_stats_update_begin/end blocks with disabling preemption and then reenabling it. Signed-off-by: Jason A. Donenfeld Acked-by: Hannes Frederic Sowa Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

ip6tunnel: make rx/tx bytes counters consistent

2015-09-21T05:36:42+00:00

Like the previous patch, which fixes ipv4 tunnels, here is the ipv6 part. Before the patch, the external ipv6 header + gre header were included on tx. After the patch: $ ping -c1 192.168.6.121 ; ip -s l ls dev ip6gre1 PING 192.168.6.121 (192.168.6.121) 56(84) bytes of data. 64 bytes from 192.168.6.121: icmp_req=1 ttl=64 time=1.92 ms --- 192.168.6.121 ping statistics --- 1 packets transmitted, 1 received, 0% packet loss, time 0ms rtt min/avg/max/mdev = 1.923/1.923/1.923/0.000 ms 7: ip6gre1@NONE: mtu 1440 qdisc noqueue state UNKNOWN mode DEFAULT group default link/gre6 20:01:06:60:30:08:c1:c3:00:00:00:00:00:00:01:23 peer 20:01:06:60:30:08:c1:c3:00:00:00:00:00:00:01:21 RX: bytes packets errors dropped overrun mcast 84 1 0 0 0 0 TX: bytes packets errors dropped carrier collsns 84 1 0 0 0 0 $ ping -c1 192.168.1.121 ; ip -s l ls dev ip6tnl1 PING 192.168.1.121 (192.168.1.121) 56(84) bytes of data. 64 bytes from 192.168.1.121: icmp_req=1 ttl=64 time=2.28 ms --- 192.168.1.121 ping statistics --- 1 packets transmitted, 1 received, 0% packet loss, time 0ms rtt min/avg/max/mdev = 2.288/2.288/2.288/0.000 ms 8: ip6tnl1@NONE: mtu 1452 qdisc noqueue state UNKNOWN mode DEFAULT group default link/tunnel6 2001:660:3008:c1c3::123 peer 2001:660:3008:c1c3::121 RX: bytes packets errors dropped overrun mcast 84 1 0 0 0 0 TX: bytes packets errors dropped carrier collsns 84 1 0 0 0 0 Signed-off-by: Nicolas Dichtel Signed-off-by: David S. Miller

ipv6: Replace spinlock with seqlock and rcu in ip6_tunnel

2015-09-15T21:53:05+00:00

This patch uses a seqlock to ensure consistency between idst->dst and idst->cookie. It also makes dst freeing from fib tree to undergo a rcu grace period. Signed-off-by: Martin KaFai Lau Signed-off-by: David S. Miller

ipv6: Fix dst_entry refcnt bugs in ip6_tunnel

2015-09-15T21:53:05+00:00

Problems in the current dst_entry cache in the ip6_tunnel: 1. ip6_tnl_dst_set is racy. There is no lock to protect it: - One major problem is that the dst refcnt gets messed up. F.e. the same dst_cache can be released multiple times and then triggering the infamous dst refcnt < 0 warning message. - Another issue is the inconsistency between dst_cache and dst_cookie. It can be reproduced by adding and removing the ip6gre tunnel while running a super_netperf TCP_CRR test. 2. ip6_tnl_dst_get does not take the dst refcnt before returning the dst. This patch: 1. Create a percpu dst_entry cache in ip6_tnl 2. Use a spinlock to protect the dst_cache operations 3. ip6_tnl_dst_get always takes the dst refcnt before returning Signed-off-by: Martin KaFai Lau Signed-off-by: David S. Miller

ipv6: Rename the dst_cache helper functions in ip6_tunnel

2015-09-15T21:53:04+00:00

It is a prep work to fix the dst_entry refcnt bugs in ip6_tunnel. This patch rename: 1. ip6_tnl_dst_check() to ip6_tnl_dst_get() to better reflect that it will take a dst refcnt in the next patch. 2. ip6_tnl_dst_store() to ip6_tnl_dst_set() to have a more conventional name matching with ip6_tnl_dst_get(). Signed-off-by: Martin KaFai Lau Signed-off-by: David S. Miller

udp_tunnel: Pass UDP socket down through udp_tunnel{, 6}_xmit_skb().

2015-04-07T19:29:08+00:00

That was we can make sure the output path of ipv4/ipv6 operate on the UDP socket rather than whatever random thing happens to be in skb->sk. Based upon a patch by Jiri Pirko. Signed-off-by: David S. Miller Acked-by: Hannes Frederic Sowa

ip6tnl,gre6,vti6: implement ndo_get_iflink

2015-04-02T18:04:59+00:00

Don't use dev->iflink anymore. CC: Steffen Klassert Signed-off-by: Nicolas Dichtel Signed-off-by: David S. Miller

tunnels: advertise link netns via netlink

2015-01-19T19:32:03+00:00

Implement rtnl_link_ops->get_link_net() callback so that IFLA_LINK_NETNSID is added to rtnetlink messages. Signed-off-by: Nicolas Dichtel Signed-off-by: David S. Miller

ipv6: Allow sending packets through tunnels with wildcard endpoints

2014-11-06T19:19:19+00:00

Currently we need the IP6_TNL_F_CAP_XMIT capabiltiy to transmit packets through an ipv6 tunnel. This capability is set when the tunnel gets configured, based on the tunnel endpoint addresses. On tunnels with wildcard tunnel endpoints, we need to do the capabiltiy checking on a per packet basis like it is done in the receive path. This patch extends ip6_tnl_xmit_ctl() to take local and remote addresses as parameters to allow for per packet capabiltiy checking. Signed-off-by: Steffen Klassert Signed-off-by: David S. Miller

net: unify the pcpu_tstats and br_cpu_netstats as one

2014-01-05T01:10:24+00:00

They are same, so unify them as one, pcpu_sw_netstats. Define pcpu_sw_netstat in netdevice.h, remove pcpu_tstats from if_tunnel and remove br_cpu_netstats from br_private.h Cc: Cong Wang Cc: Stephen Hemminger Signed-off-by: Li RongQing Signed-off-by: David S. Miller