From owner-freebsd-ppc@FreeBSD.ORG Tue Jul 10 20:23:38 2012 Return-Path: Delivered-To: freebsd-ppc@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id 2F2A61065673; Tue, 10 Jul 2012 20:23:38 +0000 (UTC) (envelope-from andreast-list@fgznet.ch) Received: from smtp.fgznet.ch (mail.fgznet.ch [81.92.96.47]) by mx1.freebsd.org (Postfix) with ESMTP id 9D9A78FC1C; Tue, 10 Jul 2012 20:23:37 +0000 (UTC) Received: from deuterium.andreas.nets (dhclient-91-190-14-19.flashcable.ch [91.190.14.19]) by smtp.fgznet.ch (8.13.8/8.13.8/Submit_SMTPAUTH) with ESMTP id q6AKNSE9097624; Tue, 10 Jul 2012 22:23:29 +0200 (CEST) (envelope-from andreast-list@fgznet.ch) Message-ID: <4FFC8F40.90505@fgznet.ch> Date: Tue, 10 Jul 2012 22:23:28 +0200 From: Andreas Tobler User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.5; rv:13.0) Gecko/20120601 Thunderbird/13.0 MIME-Version: 1.0 To: alc@freebsd.org References: <20120707102004.3e874201@narn.knownspace> <4FF87446.2090903@rice.edu> <4FF9F3CF.6050608@fgznet.ch> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.64 on 81.92.96.47 Cc: Alan Cox , Justin Hibbits , freebsd-ppc@freebsd.org, Alan Cox Subject: Re: Panic with latest pmap lock changes. X-BeenThere: freebsd-ppc@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Porting FreeBSD to the PowerPC List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 10 Jul 2012 20:23:38 -0000 On 10.07.12 22:00, Alan Cox wrote: > On Sun, Jul 8, 2012 at 3:55 PM, Andreas Tobler > wrote: > > On 07.07.12 19:39, Alan Cox wrote: > > On 07/07/2012 09:20, Justin Hibbits wrote: > > Looks like I spoke too soon about the pmap lock changes > working on my > G4. After about 24 hours of uptime, it panicked with the > following: > > _rw_wlock_hard: recursing but non-recursive rw pmap pv global > @ /home/chmeee/freebsd/src/sys/__powerpc/aim/mmu_oea.c:2301 > > I think the attached patch should fix it (Untested, except for > compiling). > > > Ugh. Sorry. > > The attached patch eliminates the lock recursion. While I was doing > that, I noticed that the pmap_ts_referenced() implementations on > powerpc > have the wrong return type. Oddly, the comments in mmu_if.h > have the > return type correct, but the code two or three lines later has > it wrong. > > > Fyi, I'm building world with the patch mentioned in this thread and > the kernel updated to 238258. (G5-SMP 32-bit) > > So far it looks promising. > > Before 238258 I got reliable machine locks/freeze w/o any idea what > was happening. > > If I reverted mmu_oea.c back to 238158, one before the commit from > you Alan, I was able to get a successful full world/kernel build cycle. > Yes, I confirmed that it booted, but I was not able to run a full > world/kernel cycle since I lost my GEOM_APM config ;). > > Anyway, as said, it looks promising and it will take some hours to > complete. > > > Should I commit the patch? Hmmm, I had three successful world/kernel builds with this patch. All with a GENERIC kernel. But I also had one freeze, no info/panic nothing, with a kernel where I disabled the WITNESS/INVARIANTS stuff. I think the patch is an improvement. I need to figure why I do not get any info when the machine freezes/locks whatever. But this can be done with the committed patch. Maybe we get bigger testing audience when it is committed. Thanks, Andreas