Date: Fri, 14 Apr 2017 15:00:34 -0700 From: Peter Wemm <peter@wemm.org> To: Maxim Sobolev <sobomax@freebsd.org> Cc: svn-src-head@freebsd.org, svn-src-all@freebsd.org, src-committers <src-committers@freebsd.org>, Hiren Panchasara <hiren@freebsd.org> Subject: Re: svn commit: r316874 - head/sys/kern Message-ID: <57394216.x4KIjm5Ndu@overcee.wemm.org> In-Reply-To: <CAH7qZftToe23-E05JVV0CUmFV2bu2zFuE_O6rmFObYbTdb1h4A@mail.gmail.com> References: <201704141723.v3EHNS3B043902@repo.freebsd.org> <6942092.OsECkgAp13@overcee.wemm.org> <CAH7qZftToe23-E05JVV0CUmFV2bu2zFuE_O6rmFObYbTdb1h4A@mail.gmail.com>
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--nextPart1570723.Szc7POMjpa Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="us-ascii" On Friday, April 14, 2017 02:21:05 PM Maxim Sobolev wrote: > Peter, It is actually the other way around. If you take syslogd code = out of > 11-stable and earlier that would work just fine with or without r3168= 74. > But since r285910 syslogd in head had been refactored a lot and I thi= nk > that particular bug has introduced that has been masked by the shutdo= wn() > on datagram sockets becoming a NOP after r285910. Then r316874 restor= ed our > historical behavior for the shutdown(2) and bingo, bug in the new sys= logd > code is now causing it to spin when shutdown() !=3D NOP. Ok, this makes sense. Just to be sure I'm on the same page, I should apply the syslogd.diff f= rom a=20 few messages ago and restore the shutdown(2) kernel code and give it a = spin. =20 Correct? =2DPeter > -Max >=20 > On Fri, Apr 14, 2017 at 12:46 PM, Peter Wemm <peter@wemm.org> wrote: > > On Friday, April 14, 2017 12:41:52 PM Maxim Sobolev wrote: > > > Thanks, Peter. I will try to look into this asap. > >=20 > > I don't understand what is going on yet. Presumably there must be o= ther > > changes in play that affect udp/select sometime between the origina= l 2015 > > change and this. The syslogd -s code is Old(TM). I'm also wonderin= g > > whether > > the -s code even works at all since the 2015 / r285910 change... > >=20 > > > -Max > > >=20 > > > On Apr 14, 2017 12:32 PM, "Peter Wemm" <peter@wemm.org> wrote: > > > > On Friday, April 14, 2017 11:49:26 AM Peter Wemm wrote: > > > > > On Friday, April 14, 2017 05:23:28 PM Maxim Sobolev wrote: > > > > > > Author: sobomax > > > > > > Date: Fri Apr 14 17:23:28 2017 > > > > > > New Revision: 316874 > > > > > > URL: https://svnweb.freebsd.org/changeset/base/316874 > > > > > >=20 > > > > > > Log: > > > > > > Restore ability to shutdown DGRAM sockets, still forcing > >=20 > > ENOTCONN to > >=20 > > > > be > > > >=20 > > > > > > returned by the shutdown(2) system call. This ability has b= een > >=20 > > lost as > >=20 > > > > > > part > > > > > > of the svn revision 285910. > > > > > >=20 > > > > > > Reviewed by: ed, rwatson, glebius, hiren > > > > > > MFC after: 2 weeks > > > > > > Differential Revision: https://reviews.freebsd.org/D10= 351 > > > > >=20 > > > > > This appears to have broken syslogd and had a major change in= > >=20 > > behavior > >=20 > > > > with > > > >=20 > > > > > regards to select(2). > > > > >=20 > > > > > If you run syslogd with the -s flag (which is default), it no= w spins > >=20 > > at > >=20 > > > > 100% > > > >=20 > > > > > cpu as all the shutdown sockets now return readable from sele= ct. > > > > >=20 > > > > > Old releases / jails also manifest this behavor. If it wasn'= t for > > > > > losing > > > > > the ability to run old branch binaries I'd suggest changing s= yslogd > > > > > instead, but we depend on this in the cluster and I expect ot= hers do > > > > > too. > > > > >=20 > > > > > I'm not 100% certain that this change is the culprit but a he= ads-up > > > > > can't > > > > > hurt. I'll try reverting it on the freebsd cluster next, afte= r > > > > > fixing > > > > > the > > > > > broken auditing changes. > > > > >=20 > > > > > -Peter > > > >=20 > > > > I can confirm that reverting r316874 fixes syslogd and backward= s > > > > compatability > > > > with old branches. > > > >=20 > > > > -- > > > > Peter Wemm - peter@wemm.org; peter@FreeBSD.org; peter@yahoo-inc= .com; > > > > KI6FJV > > > > UTF-8: for when a ' or ... just won\342\200\231t do\342\200\246= > >=20 > > -- > > Peter Wemm - peter@wemm.org; peter@FreeBSD.org; peter@yahoo-inc.com= ; > > KI6FJV > > UTF-8: for when a ' or ... just won\342\200\231t do\342\200\246 =2D-=20 Peter Wemm - peter@wemm.org; peter@FreeBSD.org; peter@yahoo-inc.com; KI= 6FJV UTF-8: for when a ' or ... just won\342\200\231t do\342\200\246 --nextPart1570723.Szc7POMjpa Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part. Content-Transfer-Encoding: 7Bit -----BEGIN PGP SIGNATURE----- iQEzBAABCAAdFiEEBgrA0Vr/vfNVuPoUNdaXCeyAngQFAljxRoIACgkQNdaXCeyA ngREUQf8DY28PmkYhSKmWCSz4JA1TNcgiLCFr6ybdF9FSzjHQqXph7OOFa/Galwo G14G9x1QinloDPC8bERnnOwmkJoOAr6dH4SSMsmGva00o6N8L2QJ/cUHZsntS0a9 gOnz77N3VDoRcg9x29N9LwteovKNraXRddefG+fZopkfepiBs0Xy9NHamsdodlag fN/2lThxfYNjqs+A9KWnkhOgdHal7nnwC1zhwG05I7S/0vnJRnH9j6BG+DJvo9Yh MSpyZ5fb0h62Qw61eoUtGVsr5Wz6ln1/XO+6xkCUjZwSnoTZribUaXoEH9aLArRE Uz94Fy5Uy19VNcLIffN5Kb2ERKpuLA== =wok4 -----END PGP SIGNATURE----- --nextPart1570723.Szc7POMjpa--
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