Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262515AbVCaG5r (ORCPT ); Thu, 31 Mar 2005 01:57:47 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262511AbVCaG53 (ORCPT ); Thu, 31 Mar 2005 01:57:29 -0500 Received: from grunt13.ihug.co.nz ([203.109.254.60]:65231 "EHLO grunt13.ihug.co.nz") by vger.kernel.org with ESMTP id S262515AbVCaG4c (ORCPT ); Thu, 31 Mar 2005 01:56:32 -0500 Date: Thu, 31 Mar 2005 18:43:26 +1200 (NZST) From: Bart Oldeman X-X-Sender: enbeo@enm-bo-lt.localnet To: Arjan van de Ven cc: Arnd Bergmann , Adrian Bunk , linux-kernel@vger.kernel.org, linux-msdos@vger.kernel.org, Ingo Molnar Subject: Re: 2.6.12-rc1 breaks dosemu In-Reply-To: <1111829310.6293.43.camel@laptopd505.fenrus.org> Message-ID: References: <20050320021141.GA4449@stusta.de> <200503251952.33558.arnd@arndb.de> <1111778074.6312.87.camel@laptopd505.fenrus.org> <200503252354.53154.arnd@arndb.de> <1111825501.6293.25.camel@laptopd505.fenrus.org> <1111829310.6293.43.camel@laptopd505.fenrus.org> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1762 Lines: 45 On Sat, 26 Mar 2005, Arjan van de Ven wrote: > > > There is one more improbable thing I can think of: comcom. This is > > dosemu's built-in command.com and uses some very tricky code > > (coopthreads), which certainly does not work any more with address space > > randomization. It's deprecated but was still present in 1.2.2, and Debian > > packages still used it with dosemu 1.2.1. The fix for that one is easy: > > replace your command.com with a real DOS command.com (e.g. FreeDOS > > freecom). > > > > #define STACK_GRAN_SHIFT 17 /* 128K address space granularity */ > #define STACK_GRAN (1U << STACK_GRAN_SHIFT) > #define STACK_TOP 0xc0000000U > #define STACK_BOTTOM 0xa0000000U > #define STACK_TOP_PADDING STACK_GRAN > #define STACK_SLOTS ((STACK_TOP-STACK_BOTTOM) >> STACK_GRAN_SHIFT) > > #define roundup_stacksize(size) ((size + STACK_GRAN - 1) & (-((int)STACK_GRAN))) > > that certainly isn't boding well for things.... > > > ok this thing is evil. In some private correspondence with Arnd it turned out that this code was indeed the culprit for him. Fortunately it's easy to avoid -- when you do as I wrote above it becomes dead code, and dosemu works just fine (confirmed). In default dosemu 1.2.x setups it's also dead code; it's just Debian that chose to continue using it. Fear not. The offending code has since been removed, in development versions of dosemu, if for no other reason than that except for the original author (Hans Lermen) nobody understood it. Hope that clears things up. Bart - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/