Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757479AbZCBHqU (ORCPT ); Mon, 2 Mar 2009 02:46:20 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754197AbZCBHqG (ORCPT ); Mon, 2 Mar 2009 02:46:06 -0500 Received: from mga03.intel.com ([143.182.124.21]:23222 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750879AbZCBHqF (ORCPT ); Mon, 2 Mar 2009 02:46:05 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.38,288,1233561600"; d="asc'?scan'208";a="115678024" Subject: Re: [PATCH] Fix e820 end address with EFI From: Huang Ying To: Yinghai Lu Cc: Brian Maly , Ingo Molnar , "linux-kernel@vger.kernel.org" In-Reply-To: <86802c440903011851t17e240eu9dc25116a40ca85e@mail.gmail.com> References: <49A965AD.10701@redhat.com> <86802c440902282142p14f623b8td8a88600ff2a6bbe@mail.gmail.com> <49AAEC79.3000808@redhat.com> <1235956068.6204.143.camel@yhuang-dev.sh.intel.com> <49AB38E7.60305@redhat.com> <1235960016.6204.170.camel@yhuang-dev.sh.intel.com> <49AB4171.7000508@kernel.org> <1235960708.6204.176.camel@yhuang-dev.sh.intel.com> <49AB4521.8010909@kernel.org> <1235961428.6204.190.camel@yhuang-dev.sh.intel.com> <86802c440903011851t17e240eu9dc25116a40ca85e@mail.gmail.com> Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="=-hVyPen/HKT8MB5faZiIs" Date: Mon, 02 Mar 2009 15:45:59 +0800 Message-Id: <1235979959.6204.212.camel@yhuang-dev.sh.intel.com> Mime-Version: 1.0 X-Mailer: Evolution 2.22.3.1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2006 Lines: 66 --=-hVyPen/HKT8MB5faZiIs Content-Type: text/plain Content-Transfer-Encoding: quoted-printable On Mon, 2009-03-02 at 10:51 +0800, Yinghai Lu wrote: > On Sun, Mar 1, 2009 at 6:37 PM, Huang Ying wrote: > >> so 64bit could use ioremap_cache() too? > >> we may keep 32bit and 64bit a bit consistent. > > > > If we use ioremap_cache(), kexec runtime service will not work in kexec > > situation, which needs EFI runtime memory area to be mapped at exact > > same location across kexec. I think we should support kexec if possible= . >=20 >=20 > sure. >=20 > please don't touch max_low_pfn_mapped, because some range may not > directly mapped under those efi run-time code Find an issue to use init_memory_mapping() here. If the memory range to be mapped is less than 2M, the last mapped address may be next 2M aligned position, this may lead mapping overlapping between memory range. Such as: 0x3f388000 - 0x3f488000: real mapped 0x3f388000 - 0x3f600000 0x3f590000 - 0x3f5bb000: real mapped 0x3f590000 - 0x3f600000 The problem is that the memory range 0x3f400000 - 0x3f590000 is left not mapped! Two way to fix the issue: a) Make init_memory_mapping stopped at specified end page exactly! Even for memory range smaller than 2M. b) init_memory_mapping maps all underlying pages when split large mapping. What do you think about that? Best Regards, Huang Ying --=-hVyPen/HKT8MB5faZiIs Content-Type: application/pgp-signature; name=signature.asc Content-Description: This is a digitally signed message part -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.9 (GNU/Linux) iEYEABECAAYFAkmrjrEACgkQKhFGF+eHlpgQWgCfaQW68O8AGjTPvDm9qaqXPeHH YZQAn1BuXjT20ZJNuqAogJNEbj3Er20i =fmOk -----END PGP SIGNATURE----- --=-hVyPen/HKT8MB5faZiIs-- -- 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/