From patchwork Mon Oct 18 17:45:03 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Matthew Auld X-Patchwork-Id: 12567549 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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7A74CC433F5 for ; Mon, 18 Oct 2021 17:49:42 +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 4DDD961027 for ; Mon, 18 Oct 2021 17:49:42 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 4DDD961027 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 487636EA35; Mon, 18 Oct 2021 17:49:27 +0000 (UTC) Received: from mga11.intel.com (mga11.intel.com [192.55.52.93]) by gabe.freedesktop.org (Postfix) with ESMTPS id 4112B6E9FF; Mon, 18 Oct 2021 17:49:20 +0000 (UTC) X-IronPort-AV: E=McAfee;i="6200,9189,10141"; a="225784963" X-IronPort-AV: E=Sophos;i="5.85,382,1624345200"; d="scan'208";a="225784963" Received: from orsmga001.jf.intel.com ([10.7.209.18]) by fmsmga102.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 18 Oct 2021 10:49:18 -0700 X-IronPort-AV: E=Sophos;i="5.85,382,1624345200"; d="scan'208";a="526358665" Received: from cscleary-mobl.ger.corp.intel.com (HELO mwauld-desk1.intel.com) ([10.252.13.221]) by orsmga001-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 18 Oct 2021 10:49:15 -0700 From: Matthew Auld To: intel-gfx@lists.freedesktop.org Cc: dri-devel@lists.freedesktop.org, =?utf-8?q?Thomas_Hellstr=C3=B6m?= Subject: [PATCH 4/9] drm/i915/dmabuf: add paranoid flush-on-acquire Date: Mon, 18 Oct 2021 18:45:03 +0100 Message-Id: <20211018174508.2137279-4-matthew.auld@intel.com> X-Mailer: git-send-email 2.26.3 In-Reply-To: <20211018174508.2137279-1-matthew.auld@intel.com> References: <20211018174508.2137279-1-matthew.auld@intel.com> 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" As pointed out by Thomas, we likely need to flush the pages here if the GPU can read the page contents directly from main memory. Underneath we don't know what the sg_table is pointing to, so just add a wbinvd_on_all_cpus() here, for now. Reported-by: Thomas Hellström Signed-off-by: Matthew Auld Cc: Thomas Hellström Reviewed-by: Thomas Hellström --- drivers/gpu/drm/i915/gem/i915_gem_dmabuf.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/gem/i915_gem_dmabuf.c b/drivers/gpu/drm/i915/gem/i915_gem_dmabuf.c index 5be505ebbb7b..1adcd8e02d29 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_dmabuf.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_dmabuf.c @@ -232,6 +232,7 @@ struct dma_buf *i915_gem_prime_export(struct drm_gem_object *gem_obj, int flags) static int i915_gem_object_get_pages_dmabuf(struct drm_i915_gem_object *obj) { + struct drm_i915_private *i915 = to_i915(obj->base.dev); struct sg_table *pages; unsigned int sg_page_sizes; @@ -242,8 +243,11 @@ static int i915_gem_object_get_pages_dmabuf(struct drm_i915_gem_object *obj) if (IS_ERR(pages)) return PTR_ERR(pages); - sg_page_sizes = i915_sg_dma_sizes(pages->sgl); + /* XXX: consider doing a vmap flush or something */ + if (!HAS_LLC(i915) || i915_gem_object_can_bypass_llc(obj)) + wbinvd_on_all_cpus(); + sg_page_sizes = i915_sg_dma_sizes(pages->sgl); __i915_gem_object_set_pages(obj, pages, sg_page_sizes); return 0;