From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 34E68C433DF for ; Tue, 13 Oct 2020 23:49:23 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id CDCE422201 for ; Tue, 13 Oct 2020 23:49:22 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="Ub+9ru4d" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CDCE422201 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 6F9B86B0073; Tue, 13 Oct 2020 19:49:22 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 6D14E900002; Tue, 13 Oct 2020 19:49:22 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 60EE46B007E; Tue, 13 Oct 2020 19:49:22 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0033.hostedemail.com [216.40.44.33]) by kanga.kvack.org (Postfix) with ESMTP id 35F3F6B0073 for ; Tue, 13 Oct 2020 19:49:22 -0400 (EDT) Received: from smtpin17.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id C9AAA3625 for ; Tue, 13 Oct 2020 23:49:21 +0000 (UTC) X-FDA: 77368546122.17.order28_501832c27207 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin17.hostedemail.com (Postfix) with ESMTP id AEEB8180D0184 for ; Tue, 13 Oct 2020 23:49:21 +0000 (UTC) X-HE-Tag: order28_501832c27207 X-Filterd-Recvd-Size: 6091 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf18.hostedemail.com (Postfix) with ESMTP for ; Tue, 13 Oct 2020 23:49:21 +0000 (UTC) Received: from localhost.localdomain (c-73-231-172-41.hsd1.ca.comcast.net [73.231.172.41]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id C84B722227; Tue, 13 Oct 2020 23:49:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1602632960; bh=afnh+svjHaI4xJrEHEekjDaK/jrPFtkfWOgQ5yjGNaM=; h=Date:From:To:Subject:In-Reply-To:From; b=Ub+9ru4dNjCBsq/Ki3L4dBLh1BB/JkVdzYdpGNDcmdlHMJ+Qb7X40eqP17OtwOvKf +X3GcXsCrpWPKGScuD2zIRLiL61DMmiQWQ6kuOaZkbQ3MGTNX6FGzSHji/Zt8MTFE1 FwPsB6TodPOv4XR084dC1vj0fJ/6FP+YJMgHq+To= Date: Tue, 13 Oct 2020 16:49:18 -0700 From: Andrew Morton To: airlied@linux.ie, akpm@linux-foundation.org, ard.biesheuvel@linaro.org, ardb@kernel.org, benh@kernel.crashing.org, bhelgaas@google.com, boris.ostrovsky@oracle.com, bp@alien8.de, Brice.Goglin@inria.fr, bskeggs@redhat.com, catalin.marinas@arm.com, dan.j.williams@intel.com, daniel@ffwll.ch, dave.hansen@linux.intel.com, dave.jiang@intel.com, david@redhat.com, gregkh@linuxfoundation.org, hpa@zytor.com, hulkci@huawei.com, ira.weiny@intel.com, jgg@mellanox.com, jglisse@redhat.com, jgross@suse.com, jmoyer@redhat.com, joao.m.martins@oracle.com, Jonathan.Cameron@huawei.com, justin.he@arm.com, linux-mm@kvack.org, lkp@intel.com, luto@kernel.org, mingo@redhat.com, mm-commits@vger.kernel.org, mpe@ellerman.id.au, pasha.tatashin@soleen.com, paulus@ozlabs.org, peterz@infradead.org, rafael.j.wysocki@intel.com, rdunlap@infradead.org, richard.weiyang@linux.alibaba.com, rppt@linux.ibm.com, sstabellini@kernel.org, tglx@linutronix.de, thomas.lendacky@amd.com, torvalds@linux-foundation.org, vgoyal@redhat.com, vishal.l.verma@intel.com, will@kernel.org, yanaijie@huawei.com Subject: [patch 030/181] resource: report parent to walk_iomem_res_desc() callback Message-ID: <20201013234918.e6szkz-gk%akpm@linux-foundation.org> In-Reply-To: <20201013164658.3bfd96cc224d8923e66a9f4e@linux-foundation.org> User-Agent: s-nail v14.8.16 MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: =46rom: Dan Williams Subject: resource: report parent to walk_iomem_res_desc() callback In support of detecting whether a resource might have been been claimed, report the parent to the walk_iomem_res_desc() callback. For example, the ACPI HMAT parser publishes "hmem" platform devices per target range.=20 However, if the HMAT is disabled / missing a fallback driver can attach devices to the raw memory ranges as a fallback if it sees unclaimed / orphan "Soft Reserved" resources in the resource tree. Otherwise, find_next_iomem_res() returns a resource with garbage data from the stack allocation in __walk_iomem_res_desc() for the res->parent field. There are currently no users that expect ->child and ->sibling to be valid, and the resource_lock would be needed to traverse them. Use a compound literal to implicitly zero initialize the fields that are not being returned in addition to setting ->parent. Link: https://lkml.kernel.org/r/159643097166.4062302.11875688887228572793.s= tgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams Cc: Jason Gunthorpe Cc: Dave Hansen Cc: Wei Yang Cc: Tom Lendacky Cc: Andy Lutomirski Cc: Ard Biesheuvel Cc: Benjamin Herrenschmidt Cc: Ben Skeggs Cc: Borislav Petkov Cc: Brice Goglin Cc: Catalin Marinas Cc: Daniel Vetter Cc: Dave Jiang Cc: David Airlie Cc: David Hildenbrand Cc: Greg Kroah-Hartman Cc: "H. Peter Anvin" Cc: Ingo Molnar Cc: Ira Weiny Cc: Jeff Moyer Cc: Jia He Cc: Joao Martins Cc: Jonathan Cameron Cc: Michael Ellerman Cc: Mike Rapoport Cc: Paul Mackerras Cc: Pavel Tatashin Cc: Peter Zijlstra Cc: Rafael J. Wysocki Cc: Thomas Gleixner Cc: Vishal Verma Cc: Will Deacon Cc: Ard Biesheuvel Cc: Bjorn Helgaas Cc: Boris Ostrovsky Cc: Hulk Robot Cc: Jason Yan Cc: "J=C3=A9r=C3=B4me Glisse" Cc: Juergen Gross Cc: kernel test robot Cc: Randy Dunlap Cc: Stefano Stabellini Cc: Vivek Goyal Signed-off-by: Andrew Morton --- kernel/resource.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) --- a/kernel/resource.c~resource-report-parent-to-walk_iomem_res_desc-callb= ack +++ a/kernel/resource.c @@ -382,10 +382,13 @@ static int find_next_iomem_res(resource_ =20 if (p) { /* copy data */ - res->start =3D max(start, p->start); - res->end =3D min(end, p->end); - res->flags =3D p->flags; - res->desc =3D p->desc; + *res =3D (struct resource) { + .start =3D max(start, p->start), + .end =3D min(end, p->end), + .flags =3D p->flags, + .desc =3D p->desc, + .parent =3D p->parent, + }; } =20 read_unlock(&resource_lock); _