1. 02 Oct, 2014 13 commits
    • WANG Cong's avatar
      net_sched: avoid calling tcf_unbind_filter() in call_rcu callback · a0efb80c
      WANG Cong authored
      This fixes the following crash:
      
      [   63.976822] general protection fault: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
      [   63.980094] CPU: 1 PID: 15 Comm: ksoftirqd/1 Not tainted 3.17.0-rc6+ #648
      [   63.980094] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
      [   63.980094] task: ffff880117dea690 ti: ffff880117dfc000 task.ti: ffff880117dfc000
      [   63.980094] RIP: 0010:[<ffffffff817e6d07>]  [<ffffffff817e6d07>] u32_destroy_key+0x27/0x6d
      [   63.980094] RSP: 0018:ffff880117dffcc0  EFLAGS: 00010202
      [   63.980094] RAX: ffff880117dea690 RBX: ffff8800d02e0820 RCX: 0000000000000000
      [   63.980094] RDX: 0000000000000001 RSI: 0000000000000002 RDI: 6b6b6b6b6b6b6b6b
      [   63.980094] RBP: ffff880117dffcd0 R08: 0000000000000000 R09: 0000000000000000
      [   63.980094] R10: 00006c0900006ba8 R11: 00006ba100006b9d R12: 0000000000000001
      [   63.980094] R13: ffff8800d02e0898 R14: ffffffff817e6d4d R15: ffff880117387a30
      [   63.980094] FS:  0000000000000000(0000) GS:ffff88011a800000(0000) knlGS:0000000000000000
      [   63.980094] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
      [   63.980094] CR2: 00007f07e6732fed CR3: 000000011665b000 CR4: 00000000000006e0
      [   63.980094] Stack:
      [   63.980094]  ffff88011a9cd300 ffffffff82051ac0 ffff880117dffce0 ffffffff817e6d68
      [   63.980094]  ffff880117dffd70 ffffffff810cb4c7 ffffffff810cb3cd ffff880117dfffd8
      [   63.980094]  ffff880117dea690 ffff880117dea690 ffff880117dfffd8 000000000000000a
      [   63.980094] Call Trace:
      [   63.980094]  [<ffffffff817e6d68>] u32_delete_key_freepf_rcu+0x1b/0x1d
      [   63.980094]  [<ffffffff810cb4c7>] rcu_process_callbacks+0x3bb/0x691
      [   63.980094]  [<ffffffff810cb3cd>] ? rcu_process_callbacks+0x2c1/0x691
      [   63.980094]  [<ffffffff817e6d4d>] ? u32_destroy_key+0x6d/0x6d
      [   63.980094]  [<ffffffff810780a4>] __do_softirq+0x142/0x323
      [   63.980094]  [<ffffffff810782a8>] run_ksoftirqd+0x23/0x53
      [   63.980094]  [<ffffffff81092126>] smpboot_thread_fn+0x203/0x221
      [   63.980094]  [<ffffffff81091f23>] ? smpboot_unpark_thread+0x33/0x33
      [   63.980094]  [<ffffffff8108e44d>] kthread+0xc9/0xd1
      [   63.980094]  [<ffffffff819e00ea>] ? do_wait_for_common+0xf8/0x125
      [   63.980094]  [<ffffffff8108e384>] ? __kthread_parkme+0x61/0x61
      [   63.980094]  [<ffffffff819e43ec>] ret_from_fork+0x7c/0xb0
      [   63.980094]  [<ffffffff8108e384>] ? __kthread_parkme+0x61/0x61
      
      tp could be freed in call_rcu callback too, the order is not guaranteed.
      
      John Fastabend says:
      
      ====================
      Its worth noting why this is safe. Any running schedulers will either
      read the valid class field or it will be zeroed.
      
      All schedulers today when the class is 0 do a lookup using the
      same call used by the tcf_exts_bind(). So even if we have a running
      classifier hit the null class pointer it will do a lookup and get
      to the same result. This is particularly fragile at the moment because
      the only way to verify this is to audit the schedulers call sites.
      ====================
      
      Cc: John Fastabend <john.r.fastabend@intel.com>
      Signed-off-by: default avatarCong Wang <xiyou.wangcong@gmail.com>
      Acked-by: default avatarJohn Fastabend <john.r.fastabend@intel.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      a0efb80c
    • WANG Cong's avatar
      net_sched: fix another crash in cls_tcindex · 6e056569
      WANG Cong authored
      This patch fixes the following crash:
      
      [  166.670795] BUG: unable to handle kernel NULL pointer dereference at           (null)
      [  166.674230] IP: [<ffffffff814b739f>] __list_del_entry+0x5c/0x98
      [  166.674230] PGD d0ea5067 PUD ce7fc067 PMD 0
      [  166.674230] Oops: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
      [  166.674230] CPU: 1 PID: 775 Comm: tc Not tainted 3.17.0-rc6+ #642
      [  166.674230] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
      [  166.674230] task: ffff8800d03c4d20 ti: ffff8800cae7c000 task.ti: ffff8800cae7c000
      [  166.674230] RIP: 0010:[<ffffffff814b739f>]  [<ffffffff814b739f>] __list_del_entry+0x5c/0x98
      [  166.674230] RSP: 0018:ffff8800cae7f7d0  EFLAGS: 00010207
      [  166.674230] RAX: 0000000000000000 RBX: ffff8800cba8d700 RCX: ffff8800cba8d700
      [  166.674230] RDX: 0000000000000000 RSI: dead000000200200 RDI: ffff8800cba8d700
      [  166.674230] RBP: ffff8800cae7f7d0 R08: 0000000000000001 R09: 0000000000000001
      [  166.674230] R10: 0000000000000000 R11: 000000000000859a R12: ffffffffffffffe8
      [  166.674230] R13: ffff8800cba8c5b8 R14: 0000000000000001 R15: ffff8800cba8d700
      [  166.674230] FS:  00007fdb5f04a740(0000) GS:ffff88011a800000(0000) knlGS:0000000000000000
      [  166.674230] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
      [  166.674230] CR2: 0000000000000000 CR3: 00000000cf929000 CR4: 00000000000006e0
      [  166.674230] Stack:
      [  166.674230]  ffff8800cae7f7e8 ffffffff814b73e8 ffff8800cba8d6e8 ffff8800cae7f828
      [  166.674230]  ffffffff817caeec 0000000000000046 ffff8800cba8c5b0 ffff8800cba8c5b8
      [  166.674230]  0000000000000000 0000000000000001 ffff8800cf8e33e8 ffff8800cae7f848
      [  166.674230] Call Trace:
      [  166.674230]  [<ffffffff814b73e8>] list_del+0xd/0x2b
      [  166.674230]  [<ffffffff817caeec>] tcf_action_destroy+0x4c/0x71
      [  166.674230]  [<ffffffff817ca0ce>] tcf_exts_destroy+0x20/0x2d
      [  166.674230]  [<ffffffff817ec2b5>] tcindex_delete+0x196/0x1b7
      
      struct list_head can not be simply copied and we should always init it.
      
      Cc: John Fastabend <john.r.fastabend@intel.com>
      Signed-off-by: default avatarCong Wang <xiyou.wangcong@gmail.com>
      Acked-by: default avatarJohn Fastabend <john.r.fastabend@intel.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      6e056569
    • David S. Miller's avatar
      Merge branch 'udp_gso' · 25e379c4
      David S. Miller authored
      Tom Herbert says:
      
      ====================
      udp: Generalize GSO for UDP tunnels
      
      This patch set generalizes the UDP tunnel segmentation functions so
      that they can work with various protocol encapsulations. The primary
      change is to set the inner_protocol field in the skbuff when creating
      the encapsulated packet, and then in skb_udp_tunnel_segment this data
      is used to determine the function for segmenting the encapsulated
      packet. The inner_protocol field is overloaded to take either an
      Ethertype or IP protocol.
      
      The inner_protocol is set on transmit using skb_set_inner_ipproto or
      skb_set_inner_protocol functions. VXLAN and IP tunnels (for fou GSO)
      were modified to call these.
      
      Notes:
        - GSO for GRE/UDP where GRE checksum is enabled does not work.
          Handling this will require some special case code.
        - Software GSO now supports many varieties of encapsulation with
          SKB_GSO_UDP_TUNNEL{_CSUM}. We still need a mechanism to query
          for device support of particular combinations (I intend to
          add ndo_gso_check for that).
        - MPLS seems to be the only previous user of inner_protocol. I don't
          believe these patches can affect that. For supporting GSO with
          MPLS over UDP, the inner_protocol should be set using the
          helper functions in this patch.
        - GSO for L2TP/UDP should also be straightforward now.
      
      v2:
        - Respin for Eric's restructuring of skbuff.
      
      Tested GRE, IPIP, and SIT over fou as well as VLXAN. This was
      done using 200 TCP_STREAMs in netperf.
      
       GRE
          IPv4, FOU, UDP checksum enabled
            TCP_STREAM TSO enabled on tun interface
              14.04% TX CPU utilization
              13.17% RX CPU utilization
              9211 Mbps
            TCP_STREAM TSO disabled on tun interface
              27.82% TX CPU utilization
              25.41% RX CPU utilization
              9336 Mbps
          IPv4, FOU, UDP checksum disabled
            TCP_STREAM TSO enabled on tun interface
              13.14% TX CPU utilization
              23.18% RX CPU utilization
              9277 Mbps
            TCP_STREAM TSO disabled on tun interface
              30.00% TX CPU utilization
              31.28% RX CPU utilization
              9327 Mbps
      
        IPIP
          FOU, UDP checksum enabled
            TCP_STREAM TSO enabled on tun interface
              15.28% TX CPU utilization
              13.92% RX CPU utilization
              9342 Mbps
            TCP_STREAM TSO disabled on tun interface
              27.82% TX CPU utilization
              25.41% RX CPU utilization
              9336 Mbps
          FOU, UDP checksum disabled
            TCP_STREAM TSO enabled on tun interface
              15.08% TX CPU utilization
              24.64% RX CPU utilization
              9226 Mbps
            TCP_STREAM TSO disabled on tun interface
              30.00% TX CPU utilization
              31.28% RX CPU utilization
              9327 Mbps
      
        SIT
          FOU, UDP checksum enabled
            TCP_STREAM TSO enabled on tun interface
              14.47% TX CPU utilization
              14.58% RX CPU utilization
              9106 Mbps
            TCP_STREAM TSO disabled on tun interface
              31.82% TX CPU utilization
              30.82% RX CPU utilization
              9204 Mbps
          FOU, UDP checksum disabled
            TCP_STREAM TSO enabled on tun interface
              15.70% TX CPU utilization
              27.93% RX CPU utilization
              9097 Mbps
            TCP_STREAM TSO disabled on tun interface
              33.48% TX CPU utilization
              37.36% RX CPU utilization
              9197 Mbps
      
         VXLAN
            TCP_STREAM TSO enabled on tun interface
              16.42% TX CPU utilization
              23.66% RX CPU utilization
              9081 Mbps
            TCP_STREAM TSO disabled on tun interface
              30.32% TX CPU utilization
              30.55% RX CPU utilization
              9185 Mbps
      
         Baseline (no encp, TSO and LRO enabled)
            TCP_STREAM
              11.85% TX CPU utilization
              15.13% RX CPU utilization
              9452 Mbps
      ====================
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      25e379c4
    • Tom Herbert's avatar
      vxlan: Set inner protocol before transmit · 996c9fd1
      Tom Herbert authored
      Call skb_set_inner_protocol to set inner Ethernet protocol to
      ETH_P_TEB before transmit. This is needed for GSO with UDP tunnels.
      Signed-off-by: default avatarTom Herbert <therbert@google.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      996c9fd1
    • Tom Herbert's avatar
      gre: Set inner protocol in v4 and v6 GRE transmit · 54bc9bac
      Tom Herbert authored
      Call skb_set_inner_protocol to set inner Ethernet protocol to
      protocol being encapsulation by GRE before tunnel_xmit. This is
      needed for GSO if UDP encapsulation (fou) is being done.
      Signed-off-by: default avatarTom Herbert <therbert@google.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      54bc9bac
    • Tom Herbert's avatar
      ipip: Set inner IP protocol in ipip · 077c5a09
      Tom Herbert authored
      Call skb_set_inner_ipproto to set inner IP protocol to IPPROTO_IPV4
      before tunnel_xmit. This is needed if UDP encapsulation (fou) is
      being done.
      Signed-off-by: default avatarTom Herbert <therbert@google.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      077c5a09
    • Tom Herbert's avatar
      sit: Set inner IP protocol in sit · 469471cd
      Tom Herbert authored
      Call skb_set_inner_ipproto to set inner IP protocol to IPPROTO_IPV6
      before tunnel_xmit. This is needed if UDP encapsulation (fou) is
      being done.
      Signed-off-by: default avatarTom Herbert <therbert@google.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      469471cd
    • Tom Herbert's avatar
      udp: Generalize skb_udp_segment · 8bce6d7d
      Tom Herbert authored
      skb_udp_segment is the function called from udp4_ufo_fragment to
      segment a UDP tunnel packet. This function currently assumes
      segmentation is transparent Ethernet bridging (i.e. VXLAN
      encapsulation). This patch generalizes the function to
      operate on either Ethertype or IP protocol.
      
      The inner_protocol field must be set to the protocol of the inner
      header. This can now be either an Ethertype or an IP protocol
      (in a union). A new flag in the skbuff indicates which type is
      effective. skb_set_inner_protocol and skb_set_inner_ipproto
      helper functions were added to set the inner_protocol. These
      functions are called from the point where the tunnel encapsulation
      is occuring.
      
      When skb_udp_tunnel_segment is called, the function to segment the
      inner packet is selected based on the inner IP or Ethertype. In the
      case of an IP protocol encapsulation, the function is derived from
      inet[6]_offloads. In the case of Ethertype, skb->protocol is
      set to the inner_protocol and skb_mac_gso_segment is called. (GRE
      currently does this, but it might be possible to lookup the protocol
      in offload_base and call the appropriate segmenation function
      directly).
      Signed-off-by: default avatarTom Herbert <therbert@google.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      8bce6d7d
    • David S. Miller's avatar
      Merge branch 'bpf-next' · f44d61cd
      David S. Miller authored
      Alexei Starovoitov says:
      
      ====================
      bpf: add search pruning optimization and tests
      
      patch #1 commit log explains why eBPF verifier has to examine some
      instructions multiple times and describes the search pruning optimization
      that improves verification speed for branchy programs and allows more
      complex programs to be verified successfully.
      This patch completes the core verifier logic.
      
      patch #2 adds more verifier tests related to branches and search pruning
      
      I'm still working on Andy's 'bitmask for stack slots' suggestion. It will be
      done on top of this patch.
      
      The current verifier algorithm is brute force depth first search with
      state pruning. If anyone can come up with another algorithm that demonstrates
      better results, we'll replace the algorithm without affecting user space.
      
      Note verifier doesn't guarantee that all possible valid programs are accepted.
      Overly complex programs may still be rejected.
      Verifier improvements/optimizations will guarantee that if a program
      was passing verification in the past, it will still be passing.
      ====================
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      f44d61cd
    • Alexei Starovoitov's avatar
      bpf: add tests to verifier testsuite · fd10c2ef
      Alexei Starovoitov authored
      add 4 extra tests to cover jump verification better
      Signed-off-by: default avatarAlexei Starovoitov <ast@plumgrid.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      fd10c2ef
    • Alexei Starovoitov's avatar
      bpf: add search pruning optimization to verifier · f1bca824
      Alexei Starovoitov authored
      consider C program represented in eBPF:
      int filter(int arg)
      {
          int a, b, c, *ptr;
      
          if (arg == 1)
              ptr = &a;
          else if (arg == 2)
              ptr = &b;
          else
              ptr = &c;
      
          *ptr = 0;
          return 0;
      }
      eBPF verifier has to follow all possible paths through the program
      to recognize that '*ptr = 0' instruction would be safe to execute
      in all situations.
      It's doing it by picking a path towards the end and observes changes
      to registers and stack at every insn until it reaches bpf_exit.
      Then it comes back to one of the previous branches and goes towards
      the end again with potentially different values in registers.
      When program has a lot of branches, the number of possible combinations
      of branches is huge, so verifer has a hard limit of walking no more
      than 32k instructions. This limit can be reached and complex (but valid)
      programs could be rejected. Therefore it's important to recognize equivalent
      verifier states to prune this depth first search.
      
      Basic idea can be illustrated by the program (where .. are some eBPF insns):
          1: ..
          2: if (rX == rY) goto 4
          3: ..
          4: ..
          5: ..
          6: bpf_exit
      In the first pass towards bpf_exit the verifier will walk insns: 1, 2, 3, 4, 5, 6
      Since insn#2 is a branch the verifier will remember its state in verifier stack
      to come back to it later.
      Since insn#4 is marked as 'branch target', the verifier will remember its state
      in explored_states[4] linked list.
      Once it reaches insn#6 successfully it will pop the state recorded at insn#2 and
      will continue.
      Without search pruning optimization verifier would have to walk 4, 5, 6 again,
      effectively simulating execution of insns 1, 2, 4, 5, 6
      With search pruning it will check whether state at #4 after jumping from #2
      is equivalent to one recorded in explored_states[4] during first pass.
      If there is an equivalent state, verifier can prune the search at #4 and declare
      this path to be safe as well.
      In other words two states at #4 are equivalent if execution of 1, 2, 3, 4 insns
      and 1, 2, 4 insns produces equivalent registers and stack.
      Signed-off-by: default avatarAlexei Starovoitov <ast@plumgrid.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      f1bca824
    • Nimrod Andy's avatar
      net: fec: implement rx_copybreak to improve rx performance · 1b7bde6d
      Nimrod Andy authored
      - Copy short frames and keep the buffers mapped, re-allocate skb instead of
        memory copy for long frames.
      - Add support for setting/getting rx_copybreak using generic ethtool tunable
      
      Changes V3:
      * As Eric Dumazet's suggestion that removing the copybreak module parameter
        and only keep the ethtool API support for rx_copybreak.
      
      Changes V2:
      * Implements rx_copybreak
      * Rx_copybreak provides module parameter to change this value
      * Add tunable_ops support for rx_copybreak
      Signed-off-by: default avatarFugang Duan <B38611@freescale.com>
      Signed-off-by: default avatarFrank Li <Frank.Li@freescale.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      1b7bde6d
    • Eric Dumazet's avatar
      net: avoid one atomic operation in skb_clone() · ce1a4ea3
      Eric Dumazet authored
      Fast clone cloning can actually avoid an atomic_inc(), if we
      guarantee prior clone_ref value is 1.
      
      This requires a change kfree_skbmem(), to perform the
      atomic_dec_and_test() on clone_ref before setting fclone to
      SKB_FCLONE_UNAVAILABLE.
      Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      ce1a4ea3
  2. 01 Oct, 2014 24 commits
  3. 30 Sep, 2014 3 commits
    • David S. Miller's avatar
      Merge branch 'sunvnet-jumbograms' · 09bba1ca
      David S. Miller authored
      David L Stevens says:
      
      ====================
      sunvnet: add jumbo frames support
      
      This patch set updates the sunvnet driver to version 1.6 of the VIO protocol
      to support per-port exchange of MTU information and allow non-standard MTU
      sizes, including jumbo frames.
      
      Using large MTUs shows a nearly 5X throughput improvement Linux-Solaris
      and > 10X throughput improvement Linux-Linux.
      
      Changes from v8:
      	-add a short timeout to free pending skbs if a new transmit doesn't
      	 do it first per Dave Miller <davem@davemloft.net>
      Changes from v7:
      	-handle skb allocation failures in vnet_skb_shape()
      	 per Dave Miller <davem@davemloft.net>
      Changes from v6:
      	-made kernel transmit path zero-copy to remove memory n^2 scaling issue
      	 raised by Raghuram Kothakota <Raghuram.Kothakota@oracle.com>
      Changes from v5:
      	- fixed comment per Sowmini Varadhan <sowmini.varadhan@oracle.com>
      Changes from v4:
      	- changed VNET_MAXPACKET per David Laight <David.Laight@ACULAB.COM>
      	- added cookies to support non-contiguous buffers of max size
      Changes from v3:
      	- added version functions per Dave Miller <davem@davemloft.net>
      	- moved rmtu to vnet_port per Dave Miller <davem@davemloft.net>
      	- explicitly set options bits and capability flags to 0 per
      		Raghuram Kothakota <Raghuram.Kothakota@oracle.com>
      Changes from v2:
      	- make checkpatch clean
      Changes from v1:
      	- fix brace formatting per Dave Miller <davem@davemloft.net>
      ====================
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      09bba1ca
    • David L Stevens's avatar
      sunvnet: generate ICMP PTMUD messages for smaller port MTUs · a2b78e9b
      David L Stevens authored
      This patch sends ICMP and ICMPv6 messages for Path MTU Discovery when a remote
      port MTU is smaller than the device MTU. This allows mixing newer VIO protocol
      devices that support MTU negotiation with older devices that do not on the
      same vswitch. It also allows Linux-Linux LDOMs to use 64K-1 data packets even
      though Solaris vswitch is limited to <16K MTU.
      Signed-off-by: default avatarDavid L Stevens <david.stevens@oracle.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      a2b78e9b
    • David L Stevens's avatar
      sunvnet: allow admin to set sunvnet MTU · 42db672d
      David L Stevens authored
      This patch allows an admin to set the MTU on a sunvnet device to arbitrary
      values between the minimum (68) and maximum (65535) IPv4 packet sizes.
      Signed-off-by: default avatarDavid L Stevens <david.stevens@oracle.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      42db672d