• Eric Dumazet's avatar
    tun: remove ndo_poll_controller · 765cdc20
    Eric Dumazet authored
    As diagnosed by Song Liu, ndo_poll_controller() can
    be very dangerous on loaded hosts, since the cpu
    calling ndo_poll_controller() might steal all NAPI
    contexts (for all RX/TX queues of the NIC). This capture
    can last for unlimited amount of time, since one
    cpu is generally not able to drain all the queues under load.
    
    tun uses NAPI for TX completions, so we better let core
    networking stack call the napi->poll() to avoid the capture.
    Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
    Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
    765cdc20
tun.c 81.2 KB