From patchwork Tue Jul 16 09:45:03 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Eric Auger X-Patchwork-Id: 13734238 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id E3C61C3DA49 for ; Tue, 16 Jul 2024 09:47:46 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1sTelp-0006CI-5H; Tue, 16 Jul 2024 05:46:53 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1sTelm-000648-UU for qemu-devel@nongnu.org; Tue, 16 Jul 2024 05:46:50 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1sTela-0000Mb-TH for qemu-devel@nongnu.org; Tue, 16 Jul 2024 05:46:50 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1721123198; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=sFTtJtdsThEqMi7LJVZYeWhDHRsj81sqf11CY+bIUpM=; b=PSJ/MG9CIzxhjgJ9kXJMR6P9BI+NR9Q4IMShM/pHOXDDv2o8sm64p1IM60ETYeumjiCtAY Lyh3BMGVeXBGnE38jjqfv4d67mipUGXTnfnsugl2uGZowXlsrWXQZdxocMdfysJAmkLfdM uz9w/35MkWM7y5O64hQI0heJyowbYxY= Received: from mx-prod-mc-05.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-422-20GRXQARPnWqsfGkyA3HvQ-1; Tue, 16 Jul 2024 05:46:34 -0400 X-MC-Unique: 20GRXQARPnWqsfGkyA3HvQ-1 Received: from mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.4]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 880651955F0B; Tue, 16 Jul 2024 09:46:33 +0000 (UTC) Received: from laptop.redhat.com (unknown [10.39.192.185]) by mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id CE5AF300018D; Tue, 16 Jul 2024 09:46:28 +0000 (UTC) From: Eric Auger To: eric.auger.pro@gmail.com, eric.auger@redhat.com, qemu-devel@nongnu.org, qemu-arm@nongnu.org, mst@redhat.com, jean-philippe@linaro.org, peter.maydell@linaro.org, clg@redhat.com, zhenzhong.duan@intel.com, alex.williamson@redhat.com, jasowang@redhat.com Cc: yanghliu@redhat.com Subject: [PATCH 1/6] Revert "virtio-iommu: Clear IOMMUDevice when VFIO device is unplugged" Date: Tue, 16 Jul 2024 11:45:03 +0200 Message-ID: <20240716094619.1713905-2-eric.auger@redhat.com> In-Reply-To: <20240716094619.1713905-1-eric.auger@redhat.com> References: <20240716094619.1713905-1-eric.auger@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.4 Received-SPF: pass client-ip=170.10.133.124; envelope-from=eric.auger@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org This reverts commit 1b889d6e39c32d709f1114699a014b381bcf1cb1. There are different problems with that tentative fix: - Some resources are left dangling (resv_regions, host_resv_ranges) and memory subregions are left attached to the root MR although freed as embedded in the sdev IOMMUDevice. Finally the sdev->as is not destroyed and associated listeners are left. - Even when fixing the above we observe a memory corruption associated with the deallocation of the IOMMUDevice. This can be observed when a VFIO device is hotplugged, hot-unplugged and a system reset is issued. At this stage we have not been able to identify the root cause (IOMMU MR or as structs beeing overwritten and used later on?). - Another issue is HostIOMMUDevice are indexed by non aliased BDF whereas the IOMMUDevice is indexed by aliased BDF - yes the current naming is really misleading -. Given the state of the code I don't think the virtio-iommu device works in non singleton group case though. So let's revert the patch for now. This means the IOMMU MR/as survive the hotunplug. This is what is done in the intel_iommu for instance. It does not sound very logical to keep those but currently there is no symetric function to pci_device_iommu_address_space(). probe_done issue will be handled in a subsequent patch. Also resv_regions and host_resv_regions will be deallocated separately. Signed-off-by: Eric Auger Reviewed-by: Cédric Le Goater --- hw/virtio/virtio-iommu.c | 21 --------------------- 1 file changed, 21 deletions(-) diff --git a/hw/virtio/virtio-iommu.c b/hw/virtio/virtio-iommu.c index 33ae61c4a6..4e34dacd6e 100644 --- a/hw/virtio/virtio-iommu.c +++ b/hw/virtio/virtio-iommu.c @@ -467,26 +467,6 @@ static AddressSpace *virtio_iommu_find_add_as(PCIBus *bus, void *opaque, return &sdev->as; } -static void virtio_iommu_device_clear(VirtIOIOMMU *s, PCIBus *bus, int devfn) -{ - IOMMUPciBus *sbus = g_hash_table_lookup(s->as_by_busptr, bus); - IOMMUDevice *sdev; - - if (!sbus) { - return; - } - - sdev = sbus->pbdev[devfn]; - if (!sdev) { - return; - } - - g_list_free_full(sdev->resv_regions, g_free); - sdev->resv_regions = NULL; - g_free(sdev); - sbus->pbdev[devfn] = NULL; -} - static gboolean hiod_equal(gconstpointer v1, gconstpointer v2) { const struct hiod_key *key1 = v1; @@ -728,7 +708,6 @@ virtio_iommu_unset_iommu_device(PCIBus *bus, void *opaque, int devfn) } g_hash_table_remove(viommu->host_iommu_devices, &key); - virtio_iommu_device_clear(viommu, bus, devfn); } static const PCIIOMMUOps virtio_iommu_ops = {