From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D4D1C3AE19F; Wed, 24 Jun 2026 12:25:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782303957; cv=none; b=s6qf3qIltIomVLZtyZopE1zc5wRGioUe/n1Q1Yx26xO1y1aejvdAXrwsf6WImP/4sTfjgPfNBgL/csRTrdc0d1oCAlxXWRlxJUdwkzbnsRyx4auRGsLLraKv+d6t0o7DdUW/cfsfMR15uZxdBs2fAlhHqgR6Ht3gMinxZrT+dOY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782303957; c=relaxed/simple; bh=FtFq0WKT4r2lSgaGZvlrvlEpqmrahVg2BRnTRQJ6M7Y=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=okIFGTA7GeKGnJCmBzv0wIJfnW3zpSR5PdejYsvlNJyYF28WaSJ21v/iXf7SHTk9ewbdoPiPbQf7M3hvoQO2V6jjs28GHrMBUD4PHgDzP6dymj1LtOC5avNLPljdgMNJV+t3O9t4sgGPveNT8eAxbMiUf5kk56V1NmPpaKjAy1E= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=b3Jt4SgU; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="b3Jt4SgU" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C45581F000E9; Wed, 24 Jun 2026 12:25:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1782303955; bh=TQD+wAPfgrJ+We19k8i+bBm5RwCInd87+tkU1eHjd3o=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=b3Jt4SgUAlDImUqrHQSzV+QHSFDH5v2kCOo5b3UylUXkZLqEruvfdDsY4BYlJRn+0 h+gFbOPTY9YKzJj4LwA4jiazI/uFe+YKxuLKv/t21/AKbdBim+sSI97Oz/ARDETanY 13uOgMd1yv+Pu1yLkyVMprDThWSuQh7+HPebTy1FLVcpALK/ggnsG62eTdRrxJw11t 7D7+c80+aKVJ0lMXD2WwMkaiCpA365gK5Tsk4mQU2H3XN2BAk14oIaHCs+6awzBtMP /04uMk4K9NFAOhQ+pVqtmSqEmWlAXlcvEie5FSeipAdNVjDftF5iDqG56FvTH3z2pd GmKTBniydw50g== Received: from phl-compute-03.internal (phl-compute-03.internal [10.202.2.43]) by mailfauth.phl.internal (Postfix) with ESMTP id EF7A7F4008A; Wed, 24 Jun 2026 08:25:53 -0400 (EDT) Received: from phl-frontend-04 ([10.202.2.163]) by phl-compute-03.internal (MEProxy); Wed, 24 Jun 2026 08:25:53 -0400 X-ME-Sender: X-ME-Received: X-ME-Proxy-Cause: dmFkZTGQArAWzBSIqfuCjB0QzONNhA+q1CTAuSMwuEBhzBy/tzZqNdZnhLnrUk/bzcO1Ob qV5IsSKZlnlHEtJlLVg73sfCfTAynNDnYDTF4kwRi+w+FTkK0Cj/188NyX7JkGKPWfnNxe ZM17FZj2tytGZvcbggL5ccIEAiZubQjW2zQ07p6w8z8ORw0594PYKzpLhaAAFoTGFnu7lT mIFyKVlsfgsicOOXIpKoRyBfzhw2QmhbjRQVUl1F5TMPInjH/W7zYT1cpsVHPi/+sVRVBH vqkvswFzfuR86M13twlXL/uVXDyIS9Q4ttcM4JAEe/dw44lKApfjLlgg9VpuTCIqLAFjc8 lfAZXsw2ZesBSuqmCqHnfm0szX9ve6I/yW+B6kKyqC0V/2aPyrKzOTeXKquR9ugthq9ZpI 2JVQ/bsKwGCEQEXT285scThoRVpDrBEKWa0mVQfEdSFtnvAk4EsophWkKFIkvbjdR+3XfW bilOl6viVL06Aire7DQ7K4tVqWWx8hkt4cbd/EhNP+6iMuaZlLQcahtz650vQao+VKtLj+ V1oyDhTU+toFWUL8Bf4o++J3KnmI0+jQ29QFyd0y/KgrxirVQZAYNqfuMBkwYfbX6oEomz 1AKR0idZNDijlc7P9LpEqBNH+0d+VkhkmA7R+bHK9i2x+1wGYiRHHdDfjxPw X-ME-Proxy: Feedback-ID: i10464835:Fastmail Received: by mail.messagingengine.com (Postfix) with ESMTPA; Wed, 24 Jun 2026 08:25:51 -0400 (EDT) Date: Wed, 24 Jun 2026 13:25:46 +0100 From: Kiryl Shutsemau To: Zhenzhong Duan Cc: marcandre.lureau@redhat.com, david@kernel.org, rick.p.edgecombe@intel.com, prsampat@amd.com, pbonzini@redhat.com, mst@redhat.com, peterx@redhat.com, chenyi.qiang@intel.com, elena.reshetova@intel.com, michael.roth@amd.com, ackerleytng@google.com, linux-kernel@vger.kernel.org, linux-coco@lists.linux.dev, virtualization@lists.linux.dev, x86@kernel.org, yilun.xu@intel.com, xiaoyao.li@intel.com, chao.p.peng@intel.com Subject: Re: [RFCv2 PATCH 1/6] efi/unaccepted: Support hotplug memory in unaccepted bitmap via SRAT Message-ID: References: <20260623101739.79695-1-zhenzhong.duan@intel.com> <20260623101739.79695-2-zhenzhong.duan@intel.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260623101739.79695-2-zhenzhong.duan@intel.com> On Tue, Jun 23, 2026 at 06:17:32AM -0400, Zhenzhong Duan wrote: > Currently, allocate_unaccepted_bitmap() only scans the initial EFI > boot memory map. This misses hotpluggable ranges described in the > ACPI SRAT. Without early tracking, hotplug pages are accessed without > acceptance and this triggers guest crash. > > Introduce a lightweight ACPI SRAT parser to scan these regions early. > If a region has both ACPI_SRAT_MEM_ENABLED and ACPI_SRAT_MEM_HOT_PLUGGABLE > flags, expand the tracking boundaries. This avoids pulling in the full > ACPI subsystem while ensuring the bitmap covers both static memory and > hotplug memory. Ugh.. Parsing SRAT there is ugly. I would rather avoid it. Do I understand correctly that we don't have a way represent pluggable, but not present memory in EFI memory map? IIUC, EFI_MEMORY_HOT_PLUGGABLE is actually present, but unpluggable memory. Maybe it would be better just allocate bitmap upto maxmem? And fix EFI spec to add pluggable-but-not-present attribute. -- Kiryl Shutsemau / Kirill A. Shutemov