Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755147AbdFXS3b (ORCPT ); Sat, 24 Jun 2017 14:29:31 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:44248 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751482AbdFXS3a (ORCPT ); Sat, 24 Jun 2017 14:29:30 -0400 Message-ID: <1498328940.2655.44.camel@decadent.org.uk> Subject: Re: [PATCH] mm: larger stack guard gap, between vmas From: Ben Hutchings To: Hugh Dickins Cc: Linus Torvalds , Oleg Nesterov , Michal Hocko , "Jason A. Donenfeld" , Rik van Riel , Larry Woodman , "Kirill A. Shutemov" , Tony Luck , "James E.J. Bottomley" , Helge Diller , James Hogan , Laura Abbott , Willy Tarreau , Greg KH , stable , LKML Date: Sat, 24 Jun 2017 19:29:00 +0100 In-Reply-To: References: <20170622123045.GA2694@decadent.org.uk> Content-Type: multipart/signed; micalg="pgp-sha512"; protocol="application/pgp-signature"; boundary="=-5QtGkQqIuQK/3+36Y2da" X-Mailer: Evolution 3.22.6-1 Mime-Version: 1.0 X-SA-Exim-Connect-IP: 2a02:8011:400e:2:6f00:88c8:c921:d332 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3177 Lines: 82 --=-5QtGkQqIuQK/3+36Y2da Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Sat, 2017-06-24 at 02:11 -0700, Hugh Dickins wrote: > On Thu, 22 Jun 2017, Hugh Dickins wrote: > > On Thu, 22 Jun 2017, Ben Hutchings wrote: > >=C2=A0 > > > Here's my attempt at a backport to 3.2.=C2=A0 This is only tested on > > > x86_64 and I think I should introduce local variables for > > > vma_start_gap() in a few places.=C2=A0 I had to cherry-pick commit > > > 09884964335e "mm: do not grow the stack vma just because of an overru= n > > > on preceding vma" before this one (which was a clean cherry-pick). > >=C2=A0 > > Both your speed and your stamina are much better than mine; and your > > patch belies your Sturgeon's law signature.=C2=A0 I haven't got beyond = the > > architectures yet in my parallel attempt, and you do appear to be > > doing everything right (but a local variable often welcome, yes). > >=C2=A0 > > I'm giving up for the night, will contine tomorrow. > > The only discrepancy I notice so far is that I have > > arch/alpha/kernel/osf_sys.c > > arch/ia64/mm/hugetlbpage.c > > arch/sparc/kernel/sys_sparc_32.c > > in my list of changed files, but they're not in yours. >=20 > And here's my attempt at a backport to 3.2.89, at last. > I know it builds and boots and runs on x86 64 and 32, > but that's about all that I've tried. >=20 > If you diff against yours (I preferred not to send that diff, > because of the couple of rejects in yours against 3.2.89), > you'll find most of the difference is just noise from where > I used a variable, but you had not yet done so in yours. Thanks, this is much nicer. > But there are those three missing files, and there are a few > places where I have a little "if (prev) {" block at the head of > the loop after find_vma_prev(): I think those loops start off > wrongly without that. I also failed to update prev. [...] > So please at least take a look through the diff from yours, I > think you'll find a few things to bring in, but a lot to ignore. I think I'll take most of yours, thanks. Ben. --=20 Ben Hutchings Sturgeon's Law: Ninety percent of everything is crap. --=-5QtGkQqIuQK/3+36Y2da Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEErCspvTSmr92z9o8157/I7JWGEQkFAllOr2wACgkQ57/I7JWG EQmlKA//TVLDBsat1ySeXgFWDM5Z2gVZeiEEIMBjRCfncgu72OIifJroA1XmCl54 ouGQqbZTYDOMph9KIige8+zZ/0ELeNHszCIF/4llfFRFSmzFnyfT50pAJuNY+NvW tTccjLCNINzPzCJH9sQsSP4eKk4GHad0VCFukhz6QXnhjsdd0arhiFRU5sSEejqA IrDukPiJEXytxz3irdHgHlfJBFocOcm5MZWCFsBb0KKhRGDurwZqbEBZXu0ctcZn W+iQFUxy0C+5o1zKjz4Gt7EEPadvnmuZSd/jXhbXjNROiZRhMjs74MjmwuRzh2xb +E2nMBM8MGL1OyD6IwoYlJ7pO5Qpe91X02ClSXsinjrnREleDQgQYDyTloEne7vY HQfVHG/JC3Yr0P6nLjbjpSwhjzNPdwYu273UIlFOvZby59Gg8Gx4TthDzQbIRM7q e2fAQsvzvvoJ5eBJTRsjL9WYG8zVbhU41yLTJ7R+Pa1kNtoNcy8yv85I5nzL3UMw 5i3qu7bd7GZeAyrRRp16jB1bIkfyo1+T8+Uxofus+YGBx96D4OlUuNEva4rzeVPo rl7Wwwx8hg2FTgzAzsKxYoiK7k/yRqrXK4E0nKBKXEU2GiDO03Bdvxrdn3KZE9q9 47ObMX1AqM4GRgiOvIHJg+mR1wNCMJI10Ksie1oiHBttHxGF91o= =qiDZ -----END PGP SIGNATURE----- --=-5QtGkQqIuQK/3+36Y2da--