From patchwork Thu Jan 16 17:46:53 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: "Abodunrin, Akeem G" X-Patchwork-Id: 11338119 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 1BFC0138D for ; Fri, 17 Jan 2020 01:03:11 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 047A12072E for ; Fri, 17 Jan 2020 01:03:11 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 047A12072E Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 09A3B6EF33; Fri, 17 Jan 2020 01:02:57 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from mga02.intel.com (mga02.intel.com [134.134.136.20]) by gabe.freedesktop.org (Postfix) with ESMTPS id 532896EF2F; Fri, 17 Jan 2020 01:02:56 +0000 (UTC) X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga007.jf.intel.com ([10.7.209.58]) by orsmga101.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 16 Jan 2020 17:02:55 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.70,327,1574150400"; d="scan'208";a="214307351" Received: from unknown (HELO localhost.jf.intel.com) ([10.166.29.74]) by orsmga007.jf.intel.com with ESMTP; 16 Jan 2020 17:02:55 -0800 From: Akeem G Abodunrin To: akeem.g.abodunrin@intel.com, intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, omer.aran@intel.com, pragyansri.pathi@intel.com, d.scott.phillips@intel.com, david.c.stewart@intel.com, tony.luck@intel.com, jon.bloomfield@intel.com, sudeep.dutt@intel.com, daniel.vetter@intel.com, joonas.lahtinen@linux.intel.com, jani.nikula@intel.com, chris.p.wilson@intel.com, prathap.kumar.valsan@intel.com, mika.kuoppala@intel.com, francesco.balestrieri@intel.com Subject: [RFC PATCH v3 0/2] Security mitigation for Intel Gen7 HWs Date: Thu, 16 Jan 2020 09:46:53 -0800 Message-Id: <20200116174655.85926-1-akeem.g.abodunrin@intel.com> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" **** NOTE: **** This series is in active development and is not intended to be merged to mainline in its current form. The intent of the RFC is simply to outline the strategy for the mitigation, as a focus for active discussion, and to openly share progress. There has been only minimal attention paid to performance thus far, as the focus is on robustness. It is not anticipated that there will be any measurable performance impact in the final version. **** END NOTE **** Intel ID: PSIRT-TA-201910-001 CVEID: CVE-2019-14615 Summary of Vulnerability ------------------------ Insufficient control flow in certain data structures for some Intel(R) Processors with Intel Processor Graphics may allow an unauthenticated user to potentially enable information disclosure via local access Products affected: ------------------ Intel CPU’s with Gen7, Gen7.5 and Gen9 Graphics. Mitigation Summary ------------------ This patch provides mitigation for Gen7 and Gen7.5 hardware only. Patch for Gen9 devices have been provided and merged to Linux mainline, and backported to stable kernels. Note that Gen8 is not impacted due to a previously implemented workaround. The mitigation involves submitting a custom EU kernel prior to every context restore, in order to forcibly clear down residual EU and URB resources. This is currently an RFC while more analysis is performed on the performance implications. Note on Address Space Isolation (Full PPGTT) -------------------------------------------- Isolation of EU kernel assets should be considered complementary to the existing support for address space isolation (aka Full PPGTT), since without address space isolation there is minimal value in preventing leakage between EU contexts. Full PPGTT has long been supported on Gen Gfx devices since Gen8, and protection against EU residual leakage is a welcome addition for these newer platforms. By contrast, Gen7 and Gen7.5 device introduced Full PPGTT support only as a hardware development feature for anticipated Gen8 productization. Support was never intended for, or provided to the Linux kernels for these platforms. Recent work (still ongoing) to the mainline kernel is retroactively providing this support, but due to the level of complexity it is not practical to attempt to backport this to earlier stable kernels. Since without Full PPGTT, EU residuals protection has questionable benefit, *there are no plans to provide stable kernel backports for this patch series.* Mika Kuoppala (1): drm/i915: Add mechanism to submit a context WA on ring submission Prathap Kumar Valsan (1): drm/i915/gen7: Clear all EU/L3 residual contexts drivers/gpu/drm/i915/Makefile | 1 + drivers/gpu/drm/i915/gt/gen7_renderclear.c | 524 ++++++++++++++++++ drivers/gpu/drm/i915/gt/gen7_renderclear.h | 15 + drivers/gpu/drm/i915/gt/intel_gpu_commands.h | 17 +- .../gpu/drm/i915/gt/intel_ring_submission.c | 133 ++++- drivers/gpu/drm/i915/i915_utils.h | 5 + 6 files changed, 689 insertions(+), 6 deletions(-) create mode 100644 drivers/gpu/drm/i915/gt/gen7_renderclear.c create mode 100644 drivers/gpu/drm/i915/gt/gen7_renderclear.h