1. 28 Jul, 2018 2 commits
    • Paolo Abeni's avatar
      ip: hash fragments consistently · 48f41c0c
      Paolo Abeni authored
      [ Upstream commit 3dd1c9a1 ]
      
      The skb hash for locally generated ip[v6] fragments belonging
      to the same datagram can vary in several circumstances:
      * for connected UDP[v6] sockets, the first fragment get its hash
        via set_owner_w()/skb_set_hash_from_sk()
      * for unconnected IPv6 UDPv6 sockets, the first fragment can get
        its hash via ip6_make_flowlabel()/skb_get_hash_flowi6(), if
        auto_flowlabel is enabled
      
      For the following frags the hash is usually computed via
      skb_get_hash().
      The above can cause OoO for unconnected IPv6 UDPv6 socket: in that
      scenario the egress tx queue can be selected on a per packet basis
      via the skb hash.
      It may also fool flow-oriented schedulers to place fragments belonging
      to the same datagram in different flows.
      
      Fix the issue by copying the skb hash from the head frag into
      the others at fragmentation time.
      
      Before this commit:
      perf probe -a "dev_queue_xmit skb skb->hash skb->l4_hash:b1@0/8 skb->sw_hash:b1@1/8"
      netperf -H $IPV4 -t UDP_STREAM -l 5 -- -m 2000 -n &
      perf record -e probe:dev_queue_xmit -e probe:skb_set_owner_w -a sleep 0.1
      perf script
      probe:dev_queue_xmit: (ffffffff8c6b1b20) hash=3713014309 l4_hash=1 sw_hash=0
      probe:dev_queue_xmit: (ffffffff8c6b1b20) hash=0 l4_hash=0 sw_hash=0
      
      After this commit:
      probe:dev_queue_xmit: (ffffffff8c6b1b20) hash=2171763177 l4_hash=1 sw_hash=0
      probe:dev_queue_xmit: (ffffffff8c6b1b20) hash=2171763177 l4_hash=1 sw_hash=0
      
      Fixes: b73c3d0e ("net: Save TX flow hash in sock and set in skbuf on xmit")
      Fixes: 67800f9b ("ipv6: Call skb_get_hash_flowi6 to get skb->hash in ip6_make_flowlabel")
      Signed-off-by: default avatarPaolo Abeni <pabeni@redhat.com>
      Reviewed-by: default avatarEric Dumazet <edumazet@google.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      48f41c0c
    • Felix Fietkau's avatar
      MIPS: ath79: fix register address in ath79_ddr_wb_flush() · 54a634c4
      Felix Fietkau authored
      commit bc88ad2e upstream.
      
      ath79_ddr_wb_flush_base has the type void __iomem *, so register offsets
      need to be a multiple of 4 in order to access the intended register.
      Signed-off-by: default avatarFelix Fietkau <nbd@nbd.name>
      Signed-off-by: default avatarJohn Crispin <john@phrozen.org>
      Signed-off-by: default avatarPaul Burton <paul.burton@mips.com>
      Fixes: 24b0e3e8 ("MIPS: ath79: Improve the DDR controller interface")
      Patchwork: https://patchwork.linux-mips.org/patch/19912/
      Cc: Alban Bedel <albeu@free.fr>
      Cc: James Hogan <jhogan@kernel.org>
      Cc: Ralf Baechle <ralf@linux-mips.org>
      Cc: linux-mips@linux-mips.org
      Cc: stable@vger.kernel.org # 4.2+
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      54a634c4
  2. 25 Jul, 2018 38 commits