From patchwork Tue Jun 16 01:17:40 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Rajat Jain X-Patchwork-Id: 11606131 X-Patchwork-Delegate: bhelgaas@google.com Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id B36D1138C for ; Tue, 16 Jun 2020 01:18:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 95BB220776 for ; Tue, 16 Jun 2020 01:18:05 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="cY5+g1xI" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726872AbgFPBRx (ORCPT ); Mon, 15 Jun 2020 21:17:53 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53412 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726855AbgFPBRw (ORCPT ); Mon, 15 Jun 2020 21:17:52 -0400 Received: from mail-qv1-xf49.google.com (mail-qv1-xf49.google.com [IPv6:2607:f8b0:4864:20::f49]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D8E74C08C5C2 for ; Mon, 15 Jun 2020 18:17:50 -0700 (PDT) Received: by mail-qv1-xf49.google.com with SMTP id p18so14403386qvy.11 for ; Mon, 15 Jun 2020 18:17:50 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=w48/vZpRpHgwBvOvRR4dLXxoxTIWLJ/Tbv3NQjwroMA=; b=cY5+g1xIvZJv6zrortzaOeWv8O0xGNvfzNtSs5QO9rdIHlGVT63x/y8HsaA7Ib48Di +zk6NkCUybBACqHinSCBe5fb681ZFWv7+SScnvQki/3J6tzCTkIcqCWzdk8i7ExNyt50 EEv3I0+v4Fz9g52dxJaxX8X425L7dd0CZB9zzvO7vdTTmwn3+XLNJskqQDiZWaCsF5xQ 59sc88DqoHxtpcAU/f2NRM1qX9hahvquMvjcGOWIR/tg6rVcSUfdF2J7zhQun5kLBJC8 qeRgb18EhgUZ4eNJLdyZmo8JGYMxGTgLHsgMdGy1FgS/10j2IUj4BbI9hZMUi1uTGqRP vJQw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=w48/vZpRpHgwBvOvRR4dLXxoxTIWLJ/Tbv3NQjwroMA=; b=W+3OUljpqoCXHn0cMYFKzvaE0TJns2ClwsYBEzk3XF1Nx43gKxqZHricrbu8ZG+utL ZPE0YEy9Ct43PANb5l2log5Vsf567YUhgcqb55nc64l5gG/Gr6w2DDDomEZwdEJU7Pbc y23Og8k3mLjtr85Ln8XVtKcf0g+DVrD/MKOpg/7cl0UQIMyyATeaMWxZ9LNEOuBVgYqS CvXJvgbo+om/JWvo3AchpfYN9nphZbjaoda/wScPb0HNPDtAVricE3eepeL+K64vRuFm MDI17dMfLY30lnX6dtljn6mMw1e8mrL+4OTO6gSoh3+v70xzTSVu2F1hZy2JgHh64qEI fI2w== X-Gm-Message-State: AOAM530ZsiUwMH/PIidzQMTFeub3wsNhrHEN64sRgAc77ic04iXwkdvu 5iE/hnp0PRci09vUKU9KLiCqNDlSYdx8 X-Google-Smtp-Source: ABdhPJwZZbFOZsLZEoNiGS8uCk3JSEs+IYRXiB58zA0V9PGwAgSl+E0UZUh/CeZFnX4u8WZSP/gPN0YL5jNf X-Received: by 2002:a05:6214:b30:: with SMTP id w16mr6887qvj.28.1592270269984; Mon, 15 Jun 2020 18:17:49 -0700 (PDT) Date: Mon, 15 Jun 2020 18:17:40 -0700 In-Reply-To: <20200616011742.138975-1-rajatja@google.com> Message-Id: <20200616011742.138975-2-rajatja@google.com> Mime-Version: 1.0 References: <20200616011742.138975-1-rajatja@google.com> X-Mailer: git-send-email 2.27.0.290.gba653c62da-goog Subject: [PATCH 2/4] pci: set "untrusted" flag for truly external devices only From: Rajat Jain To: David Woodhouse , Lu Baolu , Joerg Roedel , Bjorn Helgaas , "Rafael J. Wysocki" , Len Brown , iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, linux-acpi@vger.kernel.org, Raj Ashok , lalithambika.krishnakumar@intel.com, Mika Westerberg , Jean-Philippe Brucker , Prashant Malani , Benson Leung , Todd Broch , Alex Levin , Mattias Nissler , Rajat Jain , Bernie Keany , Aaron Durbin , Diego Rivas , Duncan Laurie , Furquan Shaikh , Jesse Barnes , Christian Kellner , Alex Williamson , Greg Kroah-Hartman , oohall@gmail.com Cc: Rajat Jain Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org The "ExternalFacing" devices (root ports) are still internal devices that sit on the internal system fabric and thus trusted. Currently they were being marked untrusted - likely as an unintended border case. This patch uses the platform flag to identify the external facing devices and then use it to mark any downstream devices as "untrusted". The external-facing devices themselves are left as "trusted". This was discussed here: https://lkml.org/lkml/2020/6/10/1049 Signed-off-by: Rajat Jain --- drivers/iommu/intel/iommu.c | 2 +- drivers/pci/of.c | 2 +- drivers/pci/pci-acpi.c | 13 +++++++------ drivers/pci/probe.c | 2 +- include/linux/pci.h | 8 ++++++++ 5 files changed, 18 insertions(+), 9 deletions(-) diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c index 9129663a7406b..1256ca89fb519 100644 --- a/drivers/iommu/intel/iommu.c +++ b/drivers/iommu/intel/iommu.c @@ -4735,7 +4735,7 @@ static inline bool has_untrusted_dev(void) struct pci_dev *pdev = NULL; for_each_pci_dev(pdev) - if (pdev->untrusted) + if (pdev->untrusted || pdev->external_facing) return true; return false; diff --git a/drivers/pci/of.c b/drivers/pci/of.c index 27839cd2459f6..22727fc9558df 100644 --- a/drivers/pci/of.c +++ b/drivers/pci/of.c @@ -42,7 +42,7 @@ void pci_set_bus_of_node(struct pci_bus *bus) } else { node = of_node_get(bus->self->dev.of_node); if (node && of_property_read_bool(node, "external-facing")) - bus->self->untrusted = true; + bus->self->external_facing = true; } bus->dev.of_node = node; diff --git a/drivers/pci/pci-acpi.c b/drivers/pci/pci-acpi.c index 7224b1e5f2a83..492c07805caf8 100644 --- a/drivers/pci/pci-acpi.c +++ b/drivers/pci/pci-acpi.c @@ -1213,22 +1213,23 @@ static void pci_acpi_optimize_delay(struct pci_dev *pdev, ACPI_FREE(obj); } -static void pci_acpi_set_untrusted(struct pci_dev *dev) +static void pci_acpi_set_external_facing(struct pci_dev *dev) { u8 val; - if (pci_pcie_type(dev) != PCI_EXP_TYPE_ROOT_PORT) + if (pci_pcie_type(dev) != PCI_EXP_TYPE_ROOT_PORT && + pci_pcie_type(dev) != PCI_EXP_TYPE_DOWNSTREAM) return; if (device_property_read_u8(&dev->dev, "ExternalFacingPort", &val)) return; /* - * These root ports expose PCIe (including DMA) outside of the - * system so make sure we treat them and everything behind as + * These root/down ports expose PCIe (including DMA) outside of the + * system so make sure we treat everything behind them as * untrusted. */ if (val) - dev->untrusted = 1; + dev->external_facing = 1; } static void pci_acpi_setup(struct device *dev) @@ -1240,7 +1241,7 @@ static void pci_acpi_setup(struct device *dev) return; pci_acpi_optimize_delay(pci_dev, adev->handle); - pci_acpi_set_untrusted(pci_dev); + pci_acpi_set_external_facing(pci_dev); pci_acpi_add_edr_notifier(pci_dev); pci_acpi_add_pm_notifier(adev, pci_dev); diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index 6d87066a5ecc5..8c40c00413e74 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -1552,7 +1552,7 @@ static void set_pcie_untrusted(struct pci_dev *dev) * untrusted as well. */ parent = pci_upstream_bridge(dev); - if (parent && parent->untrusted) + if (parent && (parent->untrusted || parent->external_facing)) dev->untrusted = true; } diff --git a/include/linux/pci.h b/include/linux/pci.h index a26be5332bba6..fe1bc603fda40 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -432,6 +432,14 @@ struct pci_dev { * mappings to make sure they cannot access arbitrary memory. */ unsigned int untrusted:1; + /* + * Devices are marked as external-facing using info from platform + * (ACPI / devicetree). An external-facing device is still an internal + * trusted device, but it faces external untrusted devices. Thus any + * devices enumerated downstream an external-facing device is marked + * as untrusted. + */ + unsigned int external_facing:1; unsigned int broken_intx_masking:1; /* INTx masking can't be used */ unsigned int io_window_1k:1; /* Intel bridge 1K I/O windows */ unsigned int irq_managed:1;