From patchwork Tue Jul 7 22:46:03 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Rajat Jain X-Patchwork-Id: 11650375 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 8FF086C1 for ; Tue, 7 Jul 2020 22:46:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7316B20775 for ; Tue, 7 Jul 2020 22:46:23 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="pXZcXhxz" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729469AbgGGWqN (ORCPT ); Tue, 7 Jul 2020 18:46:13 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45126 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729444AbgGGWqM (ORCPT ); Tue, 7 Jul 2020 18:46:12 -0400 Received: from mail-qt1-x84a.google.com (mail-qt1-x84a.google.com [IPv6:2607:f8b0:4864:20::84a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 04B2CC08C5DC for ; Tue, 7 Jul 2020 15:46:12 -0700 (PDT) Received: by mail-qt1-x84a.google.com with SMTP id t36so13846086qtc.16 for ; Tue, 07 Jul 2020 15:46:11 -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=+Rqxcc67bWamHPT9UuHLq9P/O36CYZQMOcdNpnmmIao=; b=pXZcXhxz7mxW6RS7gJAv+NztP6PWIdXUddf5RV8kHRHOgSQsBTRWQ1kS6KDZwaXyYH yoGbwYV+lo5tqx0FRClBaQgvoKziBo4h6Z7fY1r8opn1GwexWSqz0HsRK5lgFzCx7Hto oJF9FQRenEaECQh4qFBYY48A456Srf7zC3wEtpl4CRGFVns2fUaYYgnA3QLbCwBlEBGe r2o2LBmx6Z1RS0/swh8B4gpLLRumQtdkajRNwjGtDHeKjMr7XzLJ7xp7rZtaSPPwl75U lK06Fba7oS0Ta8x3kR5Y+4Elrw6RS0PJg+Obk1PPaGMj5vur2Pd782/vmR1grIYi8RhN VFLA== 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=+Rqxcc67bWamHPT9UuHLq9P/O36CYZQMOcdNpnmmIao=; b=JgBoHpLjNnbqmwATeBhe5H/m3Dhdi7sGTzWA0i+exDYQg66Ij36yIBvlZutvmA2tUA y1qwWvFfnHgGgLZmhRCmjxqUC4+gJMyTFXbdLeqtFihciKi0uNVBeSRNqwpTmcOBxF9L 2Lr0st6PPbQalgWOl3pfp3kGxa34urCkpDGSYksryz76kDLEBCLUA+c4/sWAYLrph5wF ST+Us213PTEdjZVZjhka01nUD6ZrXGOGAj2/MWqkPNCJR5gEIVkdUAMqDRs51YDLa6Vw hlnjqxWSprSlBOx0qGG0WLafDvzp3o4Ze2E8H4uT0kme5TCgD7d4iTpudUJh1Iud5ppx cQFQ== X-Gm-Message-State: AOAM531H4yRmDECTbQ+HFGl1Z6Bh0lNUWvEmvnjEukRTA4UDchKAack3 eFJv3oXPTcg53OZAxL78rmbN6N/GpOxm X-Google-Smtp-Source: ABdhPJxnH+92NoVCcK7NZHV4Ls6bngx8p8nimLUooSLS2gVZpS5/6IxaAi2WM9zBZzRgEB7nYKaxRQqv7qfK X-Received: by 2002:a05:6214:18f2:: with SMTP id ep18mr41966212qvb.96.1594161971125; Tue, 07 Jul 2020 15:46:11 -0700 (PDT) Date: Tue, 7 Jul 2020 15:46:03 -0700 In-Reply-To: <20200707224604.3737893-1-rajatja@google.com> Message-Id: <20200707224604.3737893-3-rajatja@google.com> Mime-Version: 1.0 References: <20200707224604.3737893-1-rajatja@google.com> X-Mailer: git-send-email 2.27.0.383.g050319c2ae-goog Subject: [PATCH v4 3/4] PCI: Treat "external-facing" devices as internal 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, Saravana Kannan , Suzuki K Poulose , Arnd Bergmann , Heikki Krogerus Cc: Rajat Jain Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org The "ExternalFacingPort" devices (root ports) are internal devices that sit on the internal system fabric. Ref: https://docs.microsoft.com/en-us/windows-hardware/drivers/pci/dsd-for-pcie-root-ports Currently they were treated (marked as untrusted) at par with other external devices downstream those external facing rootports. Use the platform flag to identify the external facing devices and then treat them at par with internal devices (don't mark them untrusted). Any devices downstream continue to be marked as "untrusted". This was discussed here: https://lore.kernel.org/linux-pci/20200610230906.GA1528594@bjorn-Precision-5520/ Signed-off-by: Rajat Jain --- v4: No change v3: * fix commit log and minor code comment * Don't check for "ExternalFacingPort" on PCI_EXP_TYPE_DOWNSTREAM * Check only for pdev->external_facing in iommu.c v2: cosmetic changes in commit log drivers/iommu/intel/iommu.c | 6 +++--- drivers/pci/of.c | 2 +- drivers/pci/pci-acpi.c | 10 +++++----- drivers/pci/probe.c | 2 +- include/linux/pci.h | 8 ++++++++ 5 files changed, 18 insertions(+), 10 deletions(-) diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c index d759e7234e982..4f0f6ee2d4aaa 100644 --- a/drivers/iommu/intel/iommu.c +++ b/drivers/iommu/intel/iommu.c @@ -4738,12 +4738,12 @@ const struct attribute_group *intel_iommu_groups[] = { NULL, }; -static inline bool has_untrusted_dev(void) +static inline bool has_external_pci(void) { struct pci_dev *pdev = NULL; for_each_pci_dev(pdev) - if (pdev->untrusted) + if (pdev->external_facing) return true; return false; @@ -4751,7 +4751,7 @@ static inline bool has_untrusted_dev(void) static int __init platform_optin_force_iommu(void) { - if (!dmar_platform_optin() || no_platform_optin || !has_untrusted_dev()) + if (!dmar_platform_optin() || no_platform_optin || !has_external_pci()) return 0; if (no_iommu || dmar_disabled) 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..43a5158b2b662 100644 --- a/drivers/pci/pci-acpi.c +++ b/drivers/pci/pci-acpi.c @@ -1213,7 +1213,7 @@ 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; @@ -1223,12 +1223,12 @@ static void pci_acpi_set_untrusted(struct pci_dev *dev) 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 +1240,7 @@ 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 0ca39042507ce..281be857d2430 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 + * device 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;