From mboxrd@z Thu Jan 1 00:00:00 1970 From: Steven Smith Subject: Re: [PATCH 4 of 5] Add support for mapping grant references into HVM guests by modifying the P2M Date: Tue, 26 May 2009 12:12:18 +0100 Message-ID: <20090526111218.GA7412@weybridge.uk.xensource.com> References: <5d7aca950905252306q76bc80bbk4cb281be95a3f1d4@mail.gmail.com> <20090526090816.GA6973@weybridge.uk.xensource.com> <5d7aca950905260319j66f9f94bo77156fef41faf6cb@mail.gmail.com> Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="===============1541530645==" Return-path: In-Reply-To: <5d7aca950905260319j66f9f94bo77156fef41faf6cb@mail.gmail.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: NAHieu Cc: Steven Smith , "xen-devel@lists.xensource.com" List-Id: xen-devel@lists.xenproject.org --===============1541530645== Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="cNdxnHkX5QqsyA0e" Content-Disposition: inline --cNdxnHkX5QqsyA0e Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable > >> I believe that Xen 32bit is still important and desired by many > >> people. So please considere supporting that with your patch. > > The problem is that we only have a limited number of bits available in > > the P2M entries, which limits the number of distinct types of P2M > > entry which we can encode. =A0On 32-bit Xen, that limit is eight, of > > which seven are already used, and the grant mapping patch needs > > another two (one for read-write maps, and one for read-only). =A0There > > just isn't enough room everything we want to do. > > > > It'd be easy enough to make grant mapping work on 32-bit Xen if we > > were willing to drop some other feature (populate-on-demand, say), but > > I don't think that would be an acceptable solution. =A0Finding somewhere > > else to stash the required bits would significantly complicate things, > > and, since there aren't any particularly convincing use-cases yet for > > even the 64-bit variant, I didn't think that would be worthwhile. > OK, I see. >=20 > I want to try your patch. However, my Dom0 is 32bit, so Xen is 32 bit, > too (I compiled Xen from source code). How can I compile Xen in 64bit > for your patch now? >=20 > If it is not possible (or easy) to do that now, could you please > provide the patch to cross compile Xen in 64bit, too? > That would be useful to try your patch, and also for other things. Err... The easy way of building a 64-bit Xen is just to install a 64-bit Linux and do a native compile from there. It's possible, in principle, to cross-compile it, but it's not something I've ever done, and it requires a fair bit of fiddling to get right. I'd recommend that you install a 64-bit version of Linux somewhere and do the compilation from there, rather than trying to set up cross toolchains, unless you have absolutely no choice in the matter. Steven. --cNdxnHkX5QqsyA0e Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.6 (GNU/Linux) iD8DBQFKG86SvAgSWYI3DVMRAnylAKCaN/SXNvFaBW9fyAvNF2BPxm0IKQCglnK+ hw5FS1E6Z/57rbThAQEn8h0= =r4uL -----END PGP SIGNATURE----- --cNdxnHkX5QqsyA0e-- --===============1541530645== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel --===============1541530645==--