Bluetooth: Add NULL ACL packet stat

Remote devices use the FLOW indicator in the ACL baseband packet header to indicate to transmitting devices that the RX buffer is full. In heavily asymmetric traffic, this can generate NULL ACL packets (0-length, ACL continuation fragments).

Rather than emit log errors, track this as a device statistic instead. The corresponding user-space patch to hciconfig outputs the accumulated NULL packets with the other device statistics.

In reviewing the ioctl (HCIGETDEVINFO) used between km <-> um, I noticed there is no versioning or size information to prevent km from overwriting the um stack (eg., using an earlier version of user-space tools).

Is it generally accepted to force new Bluez with new kernel (and vice versa)? In a related query, will the mgmtops interface subsume/replace this ioctl usage as well?

Peter Hurley (1):
Bluetooth: l2cap: fix NULL ACL packet handling

 include/net/bluetooth/hci.h |    1 +
 net/bluetooth/l2cap_core.c  |    8 ++++++++
 2 files changed, 9 insertions(+), 0 deletions(-)

1.7.4.1