From mboxrd@z Thu Jan 1 00:00:00 1970 To: Lucinda Schafer cc: linuxppc-embedded@lists.linuxppc.org Subject: Re: 8xx MMU Table Walk Base (was Re: kernel crashes at Instructio nTLBMiss ) In-Reply-To: Message from Lucinda Schafer of "Mon, 19 Jun 2000 11:58:40 EST." Mime-Version: 1.0 Content-Type: text/plain Date: Tue, 20 Jun 2000 13:55:36 +1000 Message-ID: <25905.961473336@msa.cmst.csiro.au> From: Murray Jensen Sender: owner-linuxppc-embedded@lists.linuxppc.org List-Id: On Mon, 19 Jun 2000 11:58:40 -0500, Lucinda Schafer writes: >Murray, > >Were you ever able to resolve your problems? We are getting kernel mode >software emulation kernel panics in some of the routines that you mention >here on a custom MPC823 board using the 2.2.13 tarball with FPU emulation >and MM patches. > >Lucinda Schafer >Staff Software Engineer >Adaptive Micro-Ware, Inc. Hi Lucinda, my problems related to the 2.3.x/2.4.x kernel. I was describing how I fixed it for that code base. I don't believe it applies to the 2.2.x code base. You should post more details about your problem to the list (don't worry about being verbose, the more info the better - but don't post megabytes, there is a sensible balance there somewhere). People such as Dan Malek, et al, have seen much of it before, and in a majority of cases can point you to a solution very quickly. If you don't provide enough info though, you get fried in a blast furnace and you may never recover :-) Ask yourself lots of questions when describing the problem because that's what we all do when we read it. If you can answer most of the obvious questions by including info it will save two or three iterations on the mailing list (which might be days if the people asking the questions are on the opposite wake/sleep cycle to you - as is generally the case for me here in Australia, except when I hack late at night :-). Cheers! Murray... PS: for those that care, the question I raised was answered by the change I suggested being incorporated into the latest development kernel. The set_context() function now takes two arguments, the first is the usual context number, and the new second argument is the new pgdir base address (which is converted to a physical address and stored in the TWB register). I'm not sure this is a 100% correct solution, but it will work (until someone uses switch_mm() somewhere else besides the _switch() routine - I don't know how likely this is). -- Murray Jensen, CSIRO Manufacturing Sci & Tech, Phone: +61 3 9662 7763 Locked Bag No. 9, Preston, Vic, 3072, Australia. Fax: +61 3 9662 7853 Internet: Murray.Jensen@cmst.csiro.au (old address was mjj@mlb.dmt.csiro.au) ** Sent via the linuxppc-embedded mail list. See http://lists.linuxppc.org/