From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753441AbaIPJCf (ORCPT ); Tue, 16 Sep 2014 05:02:35 -0400 Received: from mga09.intel.com ([134.134.136.24]:11607 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752686AbaIPJCc (ORCPT ); Tue, 16 Sep 2014 05:02:32 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.04,533,1406617200"; d="scan'208";a="603457529" Message-ID: <5417F13B.7030500@linux.intel.com> Date: Tue, 16 Sep 2014 16:13:47 +0800 From: Jiang Liu Organization: Intel User-Agent: Mozilla/5.0 (Windows NT 6.2; WOW64; rv:24.0) Gecko/20100101 Thunderbird/24.5.0 MIME-Version: 1.0 To: Yijing Wang , Joerg Roedel , David Woodhouse , Yinghai Lu , Bjorn Helgaas , Dan Williams , Vinod Koul , "Rafael J . Wysocki" CC: Ashok Raj , Tony Luck , iommu@lists.linux-foundation.org, linux-pci@vger.kernel.org, linux-hotplug@vger.kernel.org, linux-kernel@vger.kernel.org, dmaengine@vger.kernel.org Subject: Re: [Patch Part3 V5 5/8] iommu/vt-d: Enhance intel_irq_remapping driver to support DMAR unit hotplug References: <1410487848-6027-1-git-send-email-jiang.liu@linux.intel.com> <1410487848-6027-6-git-send-email-jiang.liu@linux.intel.com> <54164D01.4060003@huawei.com> <5417E00D.5000108@linux.intel.com> <5417EC7B.4060400@huawei.com> In-Reply-To: <5417EC7B.4060400@huawei.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2014/9/16 15:53, Yijing Wang wrote: > On 2014/9/16 15:00, Jiang Liu wrote: >> On 2014/9/15 10:20, Yijing Wang wrote: >>>> +static void ir_remove_ioapic_hpet_scope(struct intel_iommu *iommu) >>>> +{ >>>> + int i; >>>> >>>> - ir_parse_one_hpet_scope(scope, iommu); >>>> - } >>>> - start += scope->length; >>>> - } >>>> + for (i = 0; i < MAX_HPET_TBS; i++) >>>> + if (ir_hpet[i].iommu == iommu) >>>> + ir_hpet[i].iommu = NULL; >>> >>> Hi Gerry, why not reset whole ir_hpe and ir_ioapic data struct? >> Hi Yijing, >> Thanks for review. Zero is legal for id, bus and devfn in >> struct ioapic_scope and struct hpet_scope. So we use domain field >> as a flag to mark entry valid or invalid and only reset iommu field. > > Hi Gerry, use iommu field as a flag to mark entry valid may be not safe enough, > I found map_hpet_to_ir() and map_ioapic_to_ir() still only check the id field to return the valid iommu. > > What about this case: > E.g. ir_hpet[2].id = N, ir_hpet[2].iommu = NULL, ir_hpet[4].id = N, ir_hpet[4].iommu = iommu; > > ir_hpet[2] maybe released yet, and the hpet now has been saved in ir_hpet[4], but map_hpet_to_irq() > will return the wrong iommu(NULL). Hi Yijing, Good catch, I will enhance map_hpet_to_ir() and map_ioapic_to_ir(). Regards! Gerry > > > static struct intel_iommu *map_hpet_to_ir(u8 hpet_id) > { > int i; > > for (i = 0; i < MAX_HPET_TBS; i++) > if (ir_hpet[i].id == hpet_id) > return ir_hpet[i].iommu; > return NULL; > } > >> >> Regards! >> Gerry >>> >>> >>> >>>> >>>> - return 0; >>>> + for (i = 0; i < MAX_IO_APICS; i++) >>>> + if (ir_ioapic[i].iommu == iommu) >>>> + ir_ioapic[i].iommu = NULL; >>>> } >>>> >>> >>> -- >>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in >>> the body of a message to majordomo@vger.kernel.org >>> More majordomo info at http://vger.kernel.org/majordomo-info.html >>> Please read the FAQ at http://www.tux.org/lkml/ >>> >> >> . >> > >