From patchwork Wed Jun 22 10:50:39 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marc Zyngier X-Patchwork-Id: 9192393 X-Patchwork-Delegate: bhelgaas@google.com Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id D178C60756 for ; Wed, 22 Jun 2016 10:51:06 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id BF0CA28329 for ; Wed, 22 Jun 2016 10:51:06 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id B279F283E9; Wed, 22 Jun 2016 10:51:06 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 16ACC28329 for ; Wed, 22 Jun 2016 10:51:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751652AbcFVKur (ORCPT ); Wed, 22 Jun 2016 06:50:47 -0400 Received: from foss.arm.com ([217.140.101.70]:46657 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751175AbcFVKup (ORCPT ); Wed, 22 Jun 2016 06:50:45 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 28E65938; Wed, 22 Jun 2016 03:51:32 -0700 (PDT) Received: from [10.1.209.129] (usa-sjc-imap-foss1.foss.arm.com [10.72.51.249]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 3BE903F213; Wed, 22 Jun 2016 03:50:41 -0700 (PDT) Subject: Re: [PATCH V7 1/8] ACPI: I/O Remapping Table (IORT) initial support To: Hanjun Guo , Tomasz Nowicki , tglx@linutronix.de, jason@lakedaemon.net, rjw@rjwysocki.net, bhelgaas@google.com, lorenzo.pieralisi@arm.com, robert.richter@caviumnetworks.com, shijie.huang@arm.com, Suravee.Suthikulpanit@amd.com References: <1466420541-20101-1-git-send-email-tn@semihalf.com> <1466420541-20101-2-git-send-email-tn@semihalf.com> <372d3b78-2bc5-94d1-49f6-c9229affa65d@linaro.org> Cc: al.stone@linaro.org, mw@semihalf.com, graeme.gregory@linaro.org, Catalin.Marinas@arm.com, will.deacon@arm.com, linux-kernel@vger.kernel.org, linux-acpi@vger.kernel.org, linux-arm-kernel@lists.infradead.org, ddaney.cavm@gmail.com, okaya@codeaurora.org, andrea.gallo@linaro.org, linux-pci@vger.kernel.org From: Marc Zyngier Organization: ARM Ltd Message-ID: <576A6D7F.6010407@arm.com> Date: Wed, 22 Jun 2016 11:50:39 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Icedove/38.7.0 MIME-Version: 1.0 In-Reply-To: <372d3b78-2bc5-94d1-49f6-c9229affa65d@linaro.org> Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP On 21/06/16 08:12, Hanjun Guo wrote: > Hi Tomasz, > > Sorry for jumping out late, just one comment below. > > On 2016/6/20 19:02, Tomasz Nowicki wrote: >> IORT shows representation of IO topology for ARM based systems. >> It describes how various components are connected together on >> parent-child basis e.g. PCI RC -> SMMU -> ITS. Also see IORT spec. >> >> Initial support allows to detect IORT table presence and save its >> root pointer obtained through acpi_get_table(). The pointer validity >> depends on acpi_gbl_permanent_mmap because if acpi_gbl_permanent_mmap >> is not set while using IORT nodes we would dereference unmapped pointers. >> >> For the aforementioned reason call iort_table_detect() from acpi_init() >> which guarantees acpi_gbl_permanent_mmap to be set at that point. >> >> Add generic helpers which are helpful for scanning and retrieving >> information from IORT table content. List of the most important helpers: >> - iort_find_dev_node() finds IORT node for a given device >> - iort_node_map_rid() maps device RID and returns IORT node which provides >> final translation >> >> Signed-off-by: Tomasz Nowicki >> --- >> drivers/acpi/Kconfig | 3 + >> drivers/acpi/Makefile | 1 + >> drivers/acpi/bus.c | 2 + >> drivers/acpi/iort.c | 220 ++++++++++++++++++++++++++++++++++++++++++++++++++ >> include/linux/iort.h | 30 +++++++ > > [...] > >> +static acpi_status >> +iort_match_node_callback(struct acpi_iort_node *node, void *context) >> +{ >> + struct device *dev = context; >> + >> + switch (node->type) { >> + case ACPI_IORT_NODE_NAMED_COMPONENT: { >> + struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; > > ACPI_ALLOCATE_BUFFER is used here, so ... > >> + struct acpi_device *adev = to_acpi_device_node(dev->fwnode); >> + struct acpi_iort_named_component *ncomp; >> + >> + if (!adev) >> + break; >> + >> + ncomp = (struct acpi_iort_named_component *)node->node_data; >> + >> + if (ACPI_FAILURE(acpi_get_name(adev->handle, >> + ACPI_FULL_PATHNAME, &buffer))) { >> + dev_warn(dev, "Can't get device full path name\n"); >> + break; >> + } >> + >> + if (!strcmp(ncomp->device_name, (char *)buffer.pointer)) >> + return AE_OK; > > ... we need to kfree(buffer.pointer) before we return or break. For the record, I've queued this patch on top: assuming that Rafael is OK with the general approach, of course. Thanks, M. diff --git a/drivers/acpi/iort.c b/drivers/acpi/iort.c index 496dcf6..3b9e55b 100644 --- a/drivers/acpi/iort.c +++ b/drivers/acpi/iort.c @@ -158,11 +158,15 @@ iort_match_node_callback(struct acpi_iort_node *node, void *context) if (ACPI_FAILURE(acpi_get_name(adev->handle, ACPI_FULL_PATHNAME, &buffer))) { dev_warn(dev, "Can't get device full path name\n"); - break; - } + } else { + int match; - if (!strcmp(ncomp->device_name, (char *)buffer.pointer)) - return AE_OK; + match = !strcmp(ncomp->device_name, buffer.pointer); + acpi_os_free(&buffer); + + if (match) + return AE_OK; + } break; }