From mboxrd@z Thu Jan 1 00:00:00 1970 Received: with ECARTIS (v1.0.0; list linux-mips); Tue, 26 Aug 2014 13:07:07 +0200 (CEST) Received: from qmta02.westchester.pa.mail.comcast.net ([76.96.62.24]:40791 "EHLO qmta02.westchester.pa.mail.comcast.net" rhost-flags-OK-OK-OK-OK) by eddie.linux-mips.org with ESMTP id S27006855AbaHZLHFcp9xk (ORCPT ); Tue, 26 Aug 2014 13:07:05 +0200 Received: from omta13.westchester.pa.mail.comcast.net ([76.96.62.52]) by qmta02.westchester.pa.mail.comcast.net with comcast id jP2i1o00317dt5G51P6zJs; Tue, 26 Aug 2014 11:06:59 +0000 Received: from [192.168.1.13] ([50.190.84.14]) by omta13.westchester.pa.mail.comcast.net with comcast id jP6y1o00H0JZ7Re3ZP6yrF; Tue, 26 Aug 2014 11:06:59 +0000 Message-ID: <53FC6A50.9090709@gentoo.org> Date: Tue, 26 Aug 2014 07:06:56 -0400 From: Joshua Kinard User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:31.0) Gecko/20100101 Thunderbird/31.0 MIME-Version: 1.0 To: linux-mips@linux-mips.org Subject: Re: 16k or 64k PAGE_SIZE and "illegal instruction" (signal -4) errors References: <53FC5300.4070902@gentoo.org> <20140826102004.GA22221@linux-mips.org> In-Reply-To: <20140826102004.GA22221@linux-mips.org> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=comcast.net; s=q20140121; t=1409051219; bh=/eoWN6EeARwMiwr/LQX9etDcMKGLBDWDGHh56nJL2nQ=; h=Received:Received:Message-ID:Date:From:MIME-Version:To:Subject: Content-Type; b=Ss0L9P/akPfHz6aSuWBmp19yyLUZeefQWWTWDs6iYOSteEeAaqtLeAfUqma5gWsen OITAHzOovHa9rzW9CLwEjvpWLPEBH/o4kABcUv1t94AY/o9/wLuDEIx92PjYotZ/e+ NxPh0DE5hQ+YMMATQ6yw88Xd98WEV7IG2hEDfM9SV0mZUFe8mXLYg+N9OchgbmN/iH iSP9tb1xsIJQYjk8iryh+2v9LJrC44ojxPueNxMJpL4v0BvCEOQH8/UnsplBWXb2kC d75voftRUhO9Rk4cql95T5suzVv+/EultRiszHtyI09uiJ7h5XeJzP+Gp+mjJaJRtk YZJth5St0z+bQ== Return-Path: X-Envelope-To: <"|/home/ecartis/ecartis -s linux-mips"> (uid 0) X-Orcpt: rfc822;linux-mips@linux-mips.org Original-Recipient: rfc822;linux-mips@linux-mips.org X-archive-position: 42253 X-ecartis-version: Ecartis v1.0.0 Sender: linux-mips-bounce@linux-mips.org Errors-to: linux-mips-bounce@linux-mips.org X-original-sender: kumba@gentoo.org Precedence: bulk List-help: List-unsubscribe: List-software: Ecartis version 1.0.0 List-Id: linux-mips X-List-ID: linux-mips List-subscribe: List-owner: List-post: List-archive: X-list: linux-mips On 08/26/2014 06:20, Ralf Baechle wrote: > On Tue, Aug 26, 2014 at 05:27:28AM -0400, Joshua Kinard wrote: > >> Okay, so from the "make kmap cache coloring aware" thread, I've been playing >> with larger PAGE_SIZE values on the Octane and O2 for the last few hours. >> 16k and 64k used to, in the past, never get far after init (usually died >> *at* init) That appears to have changed now. Most programs seem to >> JustWork(), but very randomly, I am getting a signal -4, illegal instruction >> (SIGILL) on the Octane. Both systems are running kernels w/ 64k PAGE_SIZE >> at the moment. >> >> I cannot reproduce it on demand, so I'm not really sure what the cause could >> be. PAGE_SIZE should be largely transparent to userland these days, so I am >> wondering if this might be more oddities w/ an R14000 CPU. > > This sound very unlikely as the CPU was primarily designed to run IRIX and > SGI's systems were using 16k or even 64k page size. > > What userland are you running and how old is it? Are you seeing different > results for 16k and 64k? o32 userland is the primary on both systems. However, the last SIGILL was under the 64k PAGE_SIZE kernel inside of an n32 chroot compiling the 'boost' package on the Octane, which I restarted that and it's not complained since. Also got SIGILL on the 16k PAGE_SIZE kernel when I booted 16k PAGE_SIZE the first time and ran 'ps'. Subsequent runs of 'ps' didn't reproduce the error. Also saw SIGILLs in the bootlog of the 16k PAGE_SIZE kernel when "rm" was ran once (couldn't reproduce) and when mdadm tried to put one of the arrays back together. Subsequent runs using similar argument lines don't reproduce once I got to a root shell. Being it's a Gentoo install...the o32 userland is pretty fresh. Especially on the Octane, where I literally rebuilt the old userland over 2-3 times just to make sure all the old 5-year cruft was gone. The n32 userland chroot is brand-spanking new. gcc-4.7.x only for now on both, because of PR61538 in gcc. Latest binutils. The O2 is chugging away happily so far in updating a bunch of packages. So I am leaning towards this being another quirk I have to hunt down in the Octane's code again. There isn't much in the Octane-specific code that deals with memory, though -- it seems the higher-level MIPS memory code handles most things just fine. -- Joshua Kinard Gentoo/MIPS kumba@gentoo.org 4096R/D25D95E3 2011-03-28 "The past tempts us, the present confuses us, the future frightens us. And our lives slip away, moment by moment, lost in that vast, terrible in-between." --Emperor Turhan, Centauri Republic