From owner-freebsd-current@freebsd.org Fri Aug 17 08:54:53 2018 Return-Path: Delivered-To: freebsd-current@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 6D9E710872B0 for ; Fri, 17 Aug 2018 08:54:53 +0000 (UTC) (envelope-from freebsd@grem.de) Received: from mail.grem.de (outcast.grem.de [213.239.217.27]) by mx1.freebsd.org (Postfix) with SMTP id C7C1473132 for ; Fri, 17 Aug 2018 08:54:52 +0000 (UTC) (envelope-from freebsd@grem.de) Received: (qmail 25135 invoked by uid 89); 17 Aug 2018 08:54:51 -0000 Received: from unknown (HELO ?192.168.250.192?) (mg@grem.de@46.244.231.99) by mail.grem.de with ESMTPA; 17 Aug 2018 08:54:51 -0000 Content-Type: text/plain; charset=utf-8 Mime-Version: 1.0 (1.0) Subject: Re: Fatal trap 12: page fault on Acer Chromebook 720 (peppy) From: Michael Gmelin X-Mailer: iPhone Mail (15G77) In-Reply-To: Date: Fri, 17 Aug 2018 10:54:49 +0200 Cc: Konstantin Belousov , "freebsd-current@freebsd.org" , Matthias Apitz Content-Transfer-Encoding: quoted-printable Message-Id: <07E28AC5-EBE6-4893-810A-6C03F07925C8@grem.de> References: <20180603215020.452a81d8@bsd64.grem.de> <20180603205340.GS3789@kib.kiev.ua> <20180604004632.56ca6afa@bsd64.grem.de> <20180604110654.GA2450@kib.kiev.ua> <20180604231756.2ed2adb9@bsd64.grem.de> <20180605131135.GH2450@kib.kiev.ua> <20180606010625.62632920@bsd64.grem.de> <20180815005106.69402d23@bsd64.grem.de> <20180815130447.GZ2340@kib.kiev.ua> <20180815135531.GA2340@kib.kiev.ua> To: John Baldwin X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.27 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 17 Aug 2018 08:54:53 -0000 > On 17. Aug 2018, at 08:17, John Baldwin wrote: >=20 >> On 8/16/18 1:58 PM, Michael Gmelin wrote: >>=20 >>=20 >>> On 15. Aug 2018, at 15:55, Konstantin Belousov > wrote: >>>=20 >>>> On Wed, Aug 15, 2018 at 03:52:37PM +0200, Michael Gmelin wrote: >>>>=20 >>>>=20 >>>>>> On 15. Aug 2018, at 15:04, Konstantin Belousov > wrote: >>>>>>=20 >>>>>> On Wed, Aug 15, 2018 at 12:51:06AM +0200, Michael Gmelin wrote: >>>>>> Reviving this old thread, since I just updated to r337818 and a simil= ar >>>>>> problem is happening again. Since the fix in r334799 (review >>>>>> https://reviews.freebsd.org/D15675) (mp_)machdep.c have been touched,= >>>>>> so maybe this is related >>>>>> (https://svnweb.freebsd.org/base?view=3Drevision&revision=3D334799). >>>>>>=20 >>>>>> Please see the screenshot of the panic below: >>>>>> https://gist.github.com/grembo/78d0f2a100dd4f16775b85a118769658 >>>>>>=20 >>>>>> This is me not digging any deeper, hoping that this is something >>>>>> obvious. Please let me know if you need more input. >>>>>=20 >>>>> I do not see how recent mp_machdep.c changes could affect this. >>>>> Can you try newest kernel but old loader ? >>>>=20 >>>> I will try (but that will take a while). Oh, also, it still boots in sa= ve mode/with smp disabled. >>>=20 >>> Right, this is because the access to that address through DMAP is only >>> needed when configuring AP startup resources. >>>=20 >>> Also, I think it is safe to suggest that the bisect is needed. >>=20 >> Using an older loader didn=E2=80=99t help, but I identified the problem: >>=20 >> https://svnweb.freebsd.org/base?view=3Drevision&revision=3D334952 >>=20 >> modified the code you introduced in >>=20 >> https://svnweb.freebsd.org/base?view=3Drevision&revision=3D334799 >>=20 >> By correcting units to pages it also broke booting the Chromebook as a si= de effect - so the previous fix just worked due to a bug it seems. >>=20 >> Is there an easy way to output the content of physmap at that point (debu= g.late_console=3D0 doesn=E2=80=99t work) - like an existing buffer I could u= se, or would this be more elaborate (I did something complicated last time b= ut didn=E2=80=99t save it, so any simple solution would be preferred). >=20 > How about reverting the commit for now so you get a working console > and print out the physmap array values along with Maxmem later in > the boot (or just use kgdb to examine them once the system is running)? >=20 This is before the system has a working console (part of calling getmem...),= disabling late console makes it hang, physmap changes afterwards, so runnin= g kgdb later doesn=E2=80=99t help. Last time I kept a copy of physmap and lo= gged it later to know the original content. I can do that again, I just thou= ght maybe there is a simple mechanism I=E2=80=99m not aware of that would sa= ve me some time. Thanks, Michael