From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeremy Fitzhardinge Subject: Re: [PATCH] i386: modified CONFIG_PHYSICAL_ALIGN Date: Tue, 14 Aug 2007 11:35:13 -0700 Message-ID: <46C1F5E1.6030904@goop.org> References: <5AC7DE0DDBA7B1ichiyanagi.yoshimi@lab.ntt.co.jp> <20070814032903.GB3903@bingen.suse.de> <1187061448.11093.63.camel@localhost.localdomain> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1187061448.11093.63.camel@localhost.localdomain> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: virtualization-bounces@lists.linux-foundation.org Errors-To: virtualization-bounces@lists.linux-foundation.org To: Rusty Russell Cc: zippel@linux-m68k.org, moriai.satoshi@lab.ntt.co.jp, Yoshimi Ichiyanagi , virtualization@lists.linux-foundation.org List-Id: virtualization@lists.linuxfoundation.org Rusty Russell wrote: > On Tue, 2007-08-14 at 05:29 +0200, Andi Kleen wrote: > >> On Tue, Aug 14, 2007 at 09:55:50AM +0900, Yoshimi Ichiyanagi wrote: >> >> How is this related to virtualization? >> >> >>> The problem is, if you compile x86_64 kernel, the value of >>> CONFIG_PHYSICAL_ALIGN will be fixed, and the next time you compile i386 >>> kernel, previous CONFIG_PHYSICAL_ALIGN value of x86_64(default: 2MB) will >>> be used by default. >>> >> 2/4MB is better for i386 too for PAE/non PAE because >> it will use less TLB entries. I guess it's better to just change >> the defaults. >> >> Anyways, both values should work, or did you see >> failures? >> > > I had this problem too: Lguest assumes 1MB when loading bzImages, and > the only time that gets changed is when building from an x86-64 config. > I considered it purely an lguest issue. > > The correct fix is to have lguest run bzImages rather than trying to > unpack them itself, but that requires a bootloader change, and the > proposals to do that got lost in a flurry of far more ambitious patches. > > Jeremy would know the status of that work... > A bit stalled. The format I proposed could theoretically break some bootloaders, and Eric has been too busy to talk about it. But we'll need to give it another go soon. J