Re: [PATCH] Packet loss when 'control' messages are present with large data (sendmsg(2))

On Tuesday, August 26, 2014 11:05:12 am Alan Somers wrote:
> On Mon, Aug 25, 2014 at 1:52 PM, John Baldwin <jhb_at_freebsd.org> wrote:
> > On Friday, August 22, 2014 01:34:28 PM Harald Schmalzbauer wrote:
> >>  Bezüglich Yuri's Nachricht vom 02.09.2013 06:54 (localtime):
> >> > Please check in this patch:
> >> > http://www.freebsd.org/cgi/query-pr.cgi?pr=181741
> >> > Please MFC into 9.X
> >> >
> >> > Description of the problem is within PR.
> >> >
> >> > Thanks,
> >> > Yuri
> >>
> >> Hello,
> >>
> >> I guess this fix should make it into 10.1.
> >> Can someone check please?
> >
> > A fix has to make into HEAD first.  I've cc'd Alan who responded to the bug.
> > Alan, note that glebius_at_ already committed the test case to HEAD a while ago.
> 
> First, Gleb's testcase needs to be converted to ATF.  This would be a
> good exercise for anybody who's new to ATF and wants some practice.
> Anybody interested?

While that would be nice, I don't know that it's quite fair to require the
test to be converted before working on a possible fix.  The existing test
doesn't seem that hard to run by hand:

% cd work/freebsd/head/tools/regression/sockets/unix_passfd/
% make
...
% > ./unix_passfd 
beginning test1-simplesendfd
test1-simplesendfd passed
...
beginning test8-rigths+creds+payload
unix_passfd: test8-rigths+creds+payload: recvmsg: 24 bytes received

I only say this because in the bug followup you seemed to have described a
possible solution so it seems that you would be able to develop a fix quicker
than other folks since you are already familiar with the issues involved.
(Also, you've fixed other related issues recently.)

-- 
John Baldwin