From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: mx.groups.io; dkim=missing; spf=pass (domain: redhat.com, ip: 209.132.183.28, mailfrom: lersek@redhat.com) Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28]) by groups.io with SMTP; Wed, 29 May 2019 08:12:16 -0700 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 5475AA3813; Wed, 29 May 2019 15:12:16 +0000 (UTC) Received: from lacos-laptop-7.usersys.redhat.com (ovpn-120-170.rdu2.redhat.com [10.10.120.170]) by smtp.corp.redhat.com (Postfix) with ESMTP id 92DB14DA; Wed, 29 May 2019 15:12:11 +0000 (UTC) From: "Laszlo Ersek" To: edk2-devel-groups-io Cc: Ard Biesheuvel , Gerd Hoffmann , Jordan Justen Subject: [PATCH for-edk2-stable201905 0/6] work around a QEMU issue triggered by the original TianoCore#1814 fix Date: Wed, 29 May 2019 17:12:03 +0200 Message-Id: <20190529151209.17503-1-lersek@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.30]); Wed, 29 May 2019 15:12:16 +0000 (UTC) Content-Transfer-Encoding: quoted-printable Bugzilla: https://bugzilla.tianocore.org/show_bug.cgi?id=3D1859 Repo: https://github.com/lersek/edk2.git Branch: exbar_mtrr_bz_1859 The fix (commit range 3b7a897cd8e3..39b9a5ffe661) for is technically correct, but it tickles an (arguably unjustified) assumption in QEMU the wrong way. For end users, this makes the original fix for TianoCore#1814 a regression, under certain circumstances. In theory, the assumption should be eliminated in QEMU, but in practice, that could be quite intrusive and/or take long. It seems possible to work around the problem in OVMF, satisfying the assumption again; for that, OVMF needs a different fix (and a different trade-off) for the original problem described in TianoCore#1814. Please see the detailed problem statement and the workaround's idea in TianoCore#1859. If possible, I'd like to get this into edk2-stable201905 (which we're postponing by two weeks anyway, for the sake of the OpenSSL 1.1.1b upgrade). Cc: Ard Biesheuvel Cc: Gerd Hoffmann Cc: Jordan Justen Thanks, Laszlo Laszlo Ersek (6): Revert "OvmfPkg/PlatformPei: fix MTRR for low-RAM sizes that have many bits clear" Revert "OvmfPkg/PlatformPei: reorder the 32-bit PCI window vs. the PCIEXBAR on q35" Revert "OvmfPkg/PlatformPei: hoist PciBase assignment above the i440fx/q35 branching" Revert "OvmfPkg/PlatformPei: assign PciSize on both i440fx/q35 branches explicitly" OvmfPkg: raise the PCIEXBAR base to 2816 MB on Q35 OvmfPkg/PlatformPei: set 32-bit UC area at PciBase / PciExBarBase (pc/q35) OvmfPkg/OvmfPkgIa32.dsc | 5 +- OvmfPkg/OvmfPkgIa32X64.dsc | 5 +- OvmfPkg/OvmfPkgX64.dsc | 5 +- OvmfPkg/PlatformPei/Platform.h | 5 ++ OvmfPkg/PlatformPei/MemDetect.c | 70 +++++++++++++++----- OvmfPkg/PlatformPei/Platform.c | 17 +++-- 6 files changed, 80 insertions(+), 27 deletions(-) --=20 2.19.1.3.g30247aa5d201