From patchwork Wed May 12 14:47:22 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 437931 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=-19.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT 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 E3D5BC43461 for ; Wed, 12 May 2021 16:53:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A06E76112D for ; Wed, 12 May 2021 16:53:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233998AbhELQxp (ORCPT ); Wed, 12 May 2021 12:53:45 -0400 Received: from mail.kernel.org ([198.145.29.99]:35912 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S243705AbhELQl4 (ORCPT ); Wed, 12 May 2021 12:41:56 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 97D8461CED; Wed, 12 May 2021 16:06:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1620835568; bh=vzF3faA+Qt1JZFhdELbPwUaGQAf9N5Uiy4SDCxslUpc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=UcVx+hVu/eSSK5cfGVmRODRd+9CMy+G6dgA8Wq5gvm4jNhv9gCdd1SDOfByj6fu/v xzfE7lmLvgSAuhqakjiajj8mpfo6/rluw5p5Q9M0bKK/MtG22u9fNemvnt1oibAKUq tD6G5ezEqnJZHfb8ohNPj8YbgyWDDKMM4CShrGj8= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Christoph Hellwig , Kevin Tian , Max Gurtovoy , Cornelia Huck , Eric Auger , Jason Gunthorpe , Alex Williamson , Sasha Levin Subject: [PATCH 5.12 396/677] vfio/pci: Move VGA and VF initialization to functions Date: Wed, 12 May 2021 16:47:22 +0200 Message-Id: <20210512144850.483689703@linuxfoundation.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210512144837.204217980@linuxfoundation.org> References: <20210512144837.204217980@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Jason Gunthorpe [ Upstream commit 61e90817482871b614133c0f20feb1aba2faec86 ] vfio_pci_probe() is quite complicated, with optional VF and VGA sub components. Move these into clear init/uninit functions and have a linear flow in probe/remove. This fixes a few little buglets: - vfio_pci_remove() is in the wrong order, vga_client_register() removes a notifier and is after kfree(vdev), but the notifier refers to vdev, so it can use after free in a race. - vga_client_register() can fail but was ignored Organize things so destruction order is the reverse of creation order. Fixes: ecaa1f6a0154 ("vfio-pci: Add VGA arbiter client") Reviewed-by: Christoph Hellwig Reviewed-by: Kevin Tian Reviewed-by: Max Gurtovoy Reviewed-by: Cornelia Huck Reviewed-by: Eric Auger Signed-off-by: Jason Gunthorpe Message-Id: <7-v3-225de1400dfc+4e074-vfio1_jgg@nvidia.com> Signed-off-by: Alex Williamson Signed-off-by: Sasha Levin --- drivers/vfio/pci/vfio_pci.c | 116 +++++++++++++++++++++++------------- 1 file changed, 74 insertions(+), 42 deletions(-) diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c index 5023e23db3bc..b73144a6804a 100644 --- a/drivers/vfio/pci/vfio_pci.c +++ b/drivers/vfio/pci/vfio_pci.c @@ -1924,6 +1924,68 @@ static int vfio_pci_bus_notifier(struct notifier_block *nb, return 0; } +static int vfio_pci_vf_init(struct vfio_pci_device *vdev) +{ + struct pci_dev *pdev = vdev->pdev; + int ret; + + if (!pdev->is_physfn) + return 0; + + vdev->vf_token = kzalloc(sizeof(*vdev->vf_token), GFP_KERNEL); + if (!vdev->vf_token) + return -ENOMEM; + + mutex_init(&vdev->vf_token->lock); + uuid_gen(&vdev->vf_token->uuid); + + vdev->nb.notifier_call = vfio_pci_bus_notifier; + ret = bus_register_notifier(&pci_bus_type, &vdev->nb); + if (ret) { + kfree(vdev->vf_token); + return ret; + } + return 0; +} + +static void vfio_pci_vf_uninit(struct vfio_pci_device *vdev) +{ + if (!vdev->vf_token) + return; + + bus_unregister_notifier(&pci_bus_type, &vdev->nb); + WARN_ON(vdev->vf_token->users); + mutex_destroy(&vdev->vf_token->lock); + kfree(vdev->vf_token); +} + +static int vfio_pci_vga_init(struct vfio_pci_device *vdev) +{ + struct pci_dev *pdev = vdev->pdev; + int ret; + + if (!vfio_pci_is_vga(pdev)) + return 0; + + ret = vga_client_register(pdev, vdev, NULL, vfio_pci_set_vga_decode); + if (ret) + return ret; + vga_set_legacy_decoding(pdev, vfio_pci_set_vga_decode(vdev, false)); + return 0; +} + +static void vfio_pci_vga_uninit(struct vfio_pci_device *vdev) +{ + struct pci_dev *pdev = vdev->pdev; + + if (!vfio_pci_is_vga(pdev)) + return; + vga_client_register(pdev, NULL, NULL, NULL); + vga_set_legacy_decoding(pdev, VGA_RSRC_NORMAL_IO | VGA_RSRC_NORMAL_MEM | + VGA_RSRC_LEGACY_IO | + VGA_RSRC_LEGACY_MEM); +} + static int vfio_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id) { struct vfio_pci_device *vdev; @@ -1977,28 +2039,12 @@ static int vfio_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id) ret = vfio_pci_reflck_attach(vdev); if (ret) goto out_del_group_dev; - - if (pdev->is_physfn) { - vdev->vf_token = kzalloc(sizeof(*vdev->vf_token), GFP_KERNEL); - if (!vdev->vf_token) { - ret = -ENOMEM; - goto out_reflck; - } - - mutex_init(&vdev->vf_token->lock); - uuid_gen(&vdev->vf_token->uuid); - - vdev->nb.notifier_call = vfio_pci_bus_notifier; - ret = bus_register_notifier(&pci_bus_type, &vdev->nb); - if (ret) - goto out_vf_token; - } - - if (vfio_pci_is_vga(pdev)) { - vga_client_register(pdev, vdev, NULL, vfio_pci_set_vga_decode); - vga_set_legacy_decoding(pdev, - vfio_pci_set_vga_decode(vdev, false)); - } + ret = vfio_pci_vf_init(vdev); + if (ret) + goto out_reflck; + ret = vfio_pci_vga_init(vdev); + if (ret) + goto out_vf; vfio_pci_probe_power_state(vdev); @@ -2018,8 +2064,8 @@ static int vfio_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id) return ret; -out_vf_token: - kfree(vdev->vf_token); +out_vf: + vfio_pci_vf_uninit(vdev); out_reflck: vfio_pci_reflck_put(vdev->reflck); out_del_group_dev: @@ -2041,33 +2087,19 @@ static void vfio_pci_remove(struct pci_dev *pdev) if (!vdev) return; - if (vdev->vf_token) { - WARN_ON(vdev->vf_token->users); - mutex_destroy(&vdev->vf_token->lock); - kfree(vdev->vf_token); - } - - if (vdev->nb.notifier_call) - bus_unregister_notifier(&pci_bus_type, &vdev->nb); - + vfio_pci_vf_uninit(vdev); vfio_pci_reflck_put(vdev->reflck); + vfio_pci_vga_uninit(vdev); vfio_iommu_group_put(pdev->dev.iommu_group, &pdev->dev); - kfree(vdev->region); - mutex_destroy(&vdev->ioeventfds_lock); if (!disable_idle_d3) vfio_pci_set_power_state(vdev, PCI_D0); + mutex_destroy(&vdev->ioeventfds_lock); + kfree(vdev->region); kfree(vdev->pm_save); kfree(vdev); - - if (vfio_pci_is_vga(pdev)) { - vga_client_register(pdev, NULL, NULL, NULL); - vga_set_legacy_decoding(pdev, - VGA_RSRC_NORMAL_IO | VGA_RSRC_NORMAL_MEM | - VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM); - } } static pci_ers_result_t vfio_pci_aer_err_detected(struct pci_dev *pdev,