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=-1.2 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED autolearn=ham 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 E7F4CC04AA5 for ; Mon, 15 Oct 2018 19:22:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9C8C1208D9 for ; Mon, 15 Oct 2018 19:22:20 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="lXssOpZP" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9C8C1208D9 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726914AbeJPDIy (ORCPT ); Mon, 15 Oct 2018 23:08:54 -0400 Received: from mail.kernel.org ([198.145.29.99]:54148 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726681AbeJPDIy (ORCPT ); Mon, 15 Oct 2018 23:08:54 -0400 Received: from mail-ed1-f43.google.com (mail-ed1-f43.google.com [209.85.208.43]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 14CF82145D; Mon, 15 Oct 2018 19:22:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1539631337; bh=ZPil9R+QKO8poIw11LkPFCCgJT/t/NekTHonWAJibQ8=; h=References:In-Reply-To:From:Date:Subject:To:Cc:From; b=lXssOpZPf5eraYSYN/wXeykVTyEAcGr04qUm/1/L6+sSnJ0DGTr9suSHv/aJWpN+a zsiltdMMv5luJxUkE0X1t2HhQE1VNSKNHHwt8pu/SwY+27hZDGVsYwxEshB09Lx3AF S13Om4Gbc9hqh8s3d2sk1uvCQGfhyhH5CmiSSPqI= Received: by mail-ed1-f43.google.com with SMTP id w19-v6so18947309eds.1; Mon, 15 Oct 2018 12:22:17 -0700 (PDT) X-Gm-Message-State: ABuFfohZeXHsnMFmWar8RWmTiyKoX5cstfU5sUlPVJMVGG7wucp0Txqg 27AxpxpD2YmyiHbTTp9cs/eFtdSvr3s/UWXYux4= X-Google-Smtp-Source: ACcGV61Qnys+eQd1yoQzFrVSX51ay/Zm2n8MJL7Ym6LqdOBIc72xmf2aOfNSCAnOvpozkGxWc3ElIs3yiSLGOFpDfMo= X-Received: by 2002:a50:fc06:: with SMTP id i6-v6mr22468551edr.153.1539631335410; Mon, 15 Oct 2018 12:22:15 -0700 (PDT) MIME-Version: 1.0 References: <1539563070-12969-1-git-send-email-frowand.list@gmail.com> In-Reply-To: <1539563070-12969-1-git-send-email-frowand.list@gmail.com> From: Alan Tull Date: Mon, 15 Oct 2018 14:21:39 -0500 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH v3 00/18] of: overlay: validation checks, subsequent fixes To: Frank Rowand Cc: Rob Herring , Pantelis Antoniou , Michael Ellerman , Benjamin Herrenschmidt , Paul Mackerras , Moritz Fischer , linux-kernel , linuxppc-dev , "open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" , linux-fpga@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, Oct 14, 2018 at 7:26 PM wrote: > > From: Frank Rowand > > Add checks to (1) overlay apply process and (2) memory freeing > triggered by overlay release. The checks are intended to detect > possible memory leaks and invalid overlays. > > The checks revealed bugs in existing code. Fixed the bugs. > > While fixing bugs, noted other issues, which are fixed in > separate patches. > > ***** Powerpc folks: I was not able to test the patches that > ***** directly impact Powerpc systems that use dynamic > ***** devicetree. Please review that code carefully and > ***** test. The specific patches are: 03/16, 04/16, 07/16 > > FPGA folks: > > I made the validation checks that should result in an > invalid live devicetree report "ERROR" and cause the overlay apply > to fail. > > I made the memory leak validation tests report "WARNING" and allow > the overlay apply to complete successfully. Please let me know > if you encounter the warnings. There are at least two paths > forward to deal with the cases that trigger the warning: (1) change > the warning to an error and fail the overlay apply, or (2) find a > way to detect the potential memory leaks and free the memory > appropriately. I reran my FPGA testing. The strings are fixed, no longer NULL. I have functionality back, my test passes now. I'm seeing the intended warnings about any properties added to existing nodes. That includes warnings about added symbols. Below is a simplified part to show some of what I'm seeing. By the way my testing is all using Pantelis' DT overlay configfs interface. root@arria10:~# ./apply-static-region.sh Applying dtbo: socfpga_arria10_socdk_sdmmc_ghrd_ovl_ext_cfg.dtb [ 1821.088640] OF: overlay: WARNING: add_changeset_property(), memory leak will occur if overlay removed. Property: /soc/base_fpga_region/ranges [ 1821.103307] OF: overlay: WARNING: add_changeset_property(), memory leak will occur if overlay removed. Property: /soc/base_fpga_region/external-fpga-config [ 1821.117359] OF: overlay: WARNING: add_changeset_property(), memory leak will occur if overlay removed. Property: /soc/base_fpga_region/clocks [ 1821.130130] OF: overlay: WARNING: add_changeset_property(), memory leak will occur if overlay removed. Property: /soc/base_fpga_region/clock-names [ 1821.143449] OF: overlay: WARNING: add_changeset_property(), memory leak will occur if overlay removed. Property: /__symbols__/clk_0 [ 1821.155357] OF: overlay: WARNING: add_changeset_property(), memory leak will occur if overlay removed. Property: /__symbols__/ILC [ 1821.167074] OF: overlay: WARNING: add_changeset_property(), memory leak will occur if overlay removed. Property: /__symbols__/freeze_controller_0 [ 1821.180171] OF: overlay: WARNING: add_changeset_property(), memory leak will occur if overlay removed. Property: /__symbols__/sysid_qsys_0 [ 1821.192662] OF: overlay: WARNING: add_changeset_property(), memory leak will occur if overlay removed. Property: /__symbols__/led_pio [ 1821.204720] OF: overlay: WARNING: add_changeset_property(), memory leak will occur if overlay removed. Property: /__symbols__/button_pio [ 1821.217034] OF: overlay: WARNING: add_changeset_property(), memory leak will occur if overlay removed. Property: /__symbols__/dipsw_pio [ 1821.231977] of-fpga-region soc:base_fpga_region:fpga_pr_region0: FPGA Region probed [ 1821.240144] altera_freeze_br ff200450.freeze_controller: fpga bridge [freeze] registered root@arria10:~# ./apply-static-region.sh root@arria10:~# rmdir /sys/kernel/config/device-tree/overlays/1-socfpga_arria10_socdk_sdmmc_ghrd_ovl_ext_cfg.dtb [ 1823.805564] OF: ERROR: memory leak - destroy cset entry: attach overlay node /soc/base_fpga_region/clk_0 with refcount 2 Alan Alan > > ALL people: > > The validations do _not_ address another major concern I have with > releasing overlays, which is use after free errors. > > Changes since v2: > > - 13/18: Use continue to reduce indentation in find_dup_cset_node_entry() > and find_dup_cset_prop() > > Changes since v1: > > - move patch 16/16 to 17/18 > - move patch 15/16 to 18/18 > - new patch 15/18 > - new patch 16/18 > > - 05/18: add_changeset_node() header comment: incorrect comment for @target > > - 18/18: add same fix for of_parse_phandle_with_args() > - 18/18: add same fix for of_parse_phandle_with_args_map() > > Frank Rowand (18): > of: overlay: add tests to validate kfrees from overlay removal > of: overlay: add missing of_node_put() after add new node to changeset > of: overlay: add missing of_node_get() in __of_attach_node_sysfs > powerpc/pseries: add of_node_put() in dlpar_detach_node() > of: overlay: use prop add changeset entry for property in new nodes > of: overlay: do not duplicate properties from overlay for new nodes > of: dynamic: change type of of_{at,de}tach_node() to void > of: overlay: reorder fields in struct fragment > of: overlay: validate overlay properties #address-cells and > #size-cells > of: overlay: make all pr_debug() and pr_err() messages unique > of: overlay: test case of two fragments adding same node > of: overlay: check prevents multiple fragments add or delete same node > of: overlay: check prevents multiple fragments touching same property > of: unittest: remove unused of_unittest_apply_overlay() argument > of: overlay: set node fields from properties when add new overlay node > of: unittest: allow base devicetree to have symbol metadata > of: unittest: find overlays[] entry by name instead of index > of: unittest: initialize args before calling of_*parse_*() > > arch/powerpc/platforms/pseries/dlpar.c | 15 +- > arch/powerpc/platforms/pseries/reconfig.c | 6 +- > drivers/of/dynamic.c | 68 +++-- > drivers/of/kobj.c | 4 +- > drivers/of/overlay.c | 298 ++++++++++++++++----- > drivers/of/unittest-data/Makefile | 2 + > .../of/unittest-data/overlay_bad_add_dup_node.dts | 28 ++ > .../of/unittest-data/overlay_bad_add_dup_prop.dts | 24 ++ > drivers/of/unittest-data/overlay_base.dts | 1 + > drivers/of/unittest.c | 96 +++++-- > include/linux/of.h | 19 +- > 11 files changed, 439 insertions(+), 122 deletions(-) > create mode 100644 drivers/of/unittest-data/overlay_bad_add_dup_node.dts > create mode 100644 drivers/of/unittest-data/overlay_bad_add_dup_prop.dts > > -- > Frank Rowand >