MFC r251985:
When enabling the cancellation, only process the pending cancellation
for asynchronous mode.


git-svn-id: svn://svn.freebsd.org/base/stable/9@252245 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f
MFC r251988:
Some clarifications and updates for the comments, mostly retrieved
from Bruce Evans.  Trim the trailing spaces.


git-svn-id: svn://svn.freebsd.org/base/stable/9@252246 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f
MFC r251129: libpcap 1.4.0.


git-svn-id: svn://svn.freebsd.org/base/stable/9@252281 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f
MFC: tcpdump 4.4.0.


git-svn-id: svn://svn.freebsd.org/base/stable/9@252283 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f
MFC r250613:

Fix typo in net.inet.tcp.minmss sysctl description.


git-svn-id: svn://svn.freebsd.org/base/stable/9@252285 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f
MFC r249480:
Add fdallocn function and use it when passing fds over unix socket.

This gets rid of "unp_externalize fdalloc failed" panic.


git-svn-id: svn://svn.freebsd.org/base/stable/9@252288 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f
Merge remote-tracking branch 'upstream/svn_stable_9' into svn_stable_9