This is an update version of last version to fix the handling of polling errors
in vhost/vhost_net.

Currently, vhost and vhost_net ignores errors of polling which can lead kernel
crashing for buggy/malicious userspace. Fix this by extending the idea of tx
polling state to all other vhost_polls and changing the state only when polling
succeed.

Jason Wang (3):
  vhost_net: correct error handling in vhost_net_set_backend()
  vhost: handle polling errors
  tuntap: don't add to waitqueue when POLLERR

 drivers/net/tun.c     |    5 +--
 drivers/vhost/net.c   |   89 ++++++++++++++++++++----------------------------
 drivers/vhost/vhost.c |   25 +++++++++++---
 drivers/vhost/vhost.h |   11 +++++-
 4 files changed, 68 insertions(+), 62 deletions(-)