From patchwork Tue Oct 21 10:52:54 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dheeraj Jamwal X-Patchwork-Id: 5118831 Return-Path: X-Original-To: patchwork-ltsi-dev@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork2.web.kernel.org (Postfix) with ESMTP id B5E6AC11AC for ; Tue, 21 Oct 2014 11:44:30 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id CA68C2010F for ; Tue, 21 Oct 2014 11:44:29 +0000 (UTC) Received: from mail.linuxfoundation.org (mail.linuxfoundation.org [140.211.169.12]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 96EB8200E8 for ; Tue, 21 Oct 2014 11:44:28 +0000 (UTC) Received: from mail.linux-foundation.org (localhost [127.0.0.1]) by mail.linuxfoundation.org (Postfix) with ESMTP id 53C6B109A; Tue, 21 Oct 2014 11:08:13 +0000 (UTC) X-Original-To: ltsi-dev@lists.linuxfoundation.org Delivered-To: ltsi-dev@mail.linuxfoundation.org Received: from smtp2.linuxfoundation.org (smtp2.linux-foundation.org [172.17.192.36]) by mail.linuxfoundation.org (Postfix) with ESMTPS id A1C591085 for ; Tue, 21 Oct 2014 11:08:11 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.7.6 Received: from mga01.intel.com (mga01.intel.com [192.55.52.88]) by smtp2.linuxfoundation.org (Postfix) with ESMTP id 427E71DD15 for ; Tue, 21 Oct 2014 11:08:11 +0000 (UTC) Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by fmsmga101.fm.intel.com with ESMTP; 21 Oct 2014 04:08:11 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.04,761,1406617200"; d="scan'208";a="617797338" Received: from ubuntu-desktop.png.intel.com ([10.221.122.25]) by fmsmga002.fm.intel.com with ESMTP; 21 Oct 2014 04:08:09 -0700 From: Dheeraj Jamwal To: ltsi-dev@lists.linuxfoundation.org Date: Tue, 21 Oct 2014 18:52:54 +0800 Message-Id: <1413889294-31328-575-git-send-email-dheerajx.s.jamwal@intel.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1413889294-31328-1-git-send-email-dheerajx.s.jamwal@intel.com> References: <1413889294-31328-1-git-send-email-dheerajx.s.jamwal@intel.com> X-Spam-Status: No, score=-5.6 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org Subject: [LTSI-dev] [PATCH 0574/1094] drm/i915: Only copy back the modified fields to userspace from execbuffer X-BeenThere: ltsi-dev@lists.linuxfoundation.org X-Mailman-Version: 2.1.12 Precedence: list List-Id: "A list to discuss patches, development, and other things related to the LTSI project" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: ltsi-dev-bounces@lists.linuxfoundation.org Errors-To: ltsi-dev-bounces@lists.linuxfoundation.org X-Virus-Scanned: ClamAV using ClamSMTP From: Chris Wilson We only want to modifiy a single field in the userspace view of the execbuffer command buffer, so explicitly change that rather than copy everything back again. This serves two purposes: 1. The single fields are much cheaper to copy (constant size so the copy uses special case code) and much smaller than the whole array. 2. We modify the array for internal use that need to be masked from the user. Note: We need this backported since without it the next bugfix will blow up when userspace recycles batchbuffers and relocations. Signed-off-by: Chris Wilson Cc: Daniel Vetter Cc: stable@vger.kernel.org Signed-off-by: Daniel Vetter (cherry picked from commit 9aab8bff7aa3bee567213ad3c1fdfb217bb980a2) Signed-off-by: Dheeraj Jamwal --- drivers/gpu/drm/i915/i915_gem_execbuffer.c | 54 ++++++++++++++++------------ 1 file changed, 32 insertions(+), 22 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_gem_execbuffer.c b/drivers/gpu/drm/i915/i915_gem_execbuffer.c index 48c6cb5..1557b26 100644 --- a/drivers/gpu/drm/i915/i915_gem_execbuffer.c +++ b/drivers/gpu/drm/i915/i915_gem_execbuffer.c @@ -773,9 +773,9 @@ i915_gem_execbuffer_relocate_slow(struct drm_device *dev, * relocations were valid. */ for (j = 0; j < exec[i].relocation_count; j++) { - if (copy_to_user(&user_relocs[j].presumed_offset, - &invalid_offset, - sizeof(invalid_offset))) { + if (__copy_to_user(&user_relocs[j].presumed_offset, + &invalid_offset, + sizeof(invalid_offset))) { ret = -EFAULT; mutex_lock(&dev->struct_mutex); goto err; @@ -1355,18 +1355,21 @@ i915_gem_execbuffer(struct drm_device *dev, void *data, ret = i915_gem_do_execbuffer(dev, data, file, &exec2, exec2_list); if (!ret) { + struct drm_i915_gem_exec_object __user *user_exec_list = + to_user_ptr(args->buffers_ptr); + /* Copy the new buffer offsets back to the user's exec list. */ - for (i = 0; i < args->buffer_count; i++) - exec_list[i].offset = exec2_list[i].offset; - /* ... and back out to userspace */ - ret = copy_to_user(to_user_ptr(args->buffers_ptr), - exec_list, - sizeof(*exec_list) * args->buffer_count); - if (ret) { - ret = -EFAULT; - DRM_DEBUG("failed to copy %d exec entries " - "back to user (%d)\n", - args->buffer_count, ret); + for (i = 0; i < args->buffer_count; i++) { + ret = __copy_to_user(&user_exec_list[i].offset, + &exec2_list[i].offset, + sizeof(user_exec_list[i].offset)); + if (ret) { + ret = -EFAULT; + DRM_DEBUG("failed to copy %d exec entries " + "back to user (%d)\n", + args->buffer_count, ret); + break; + } } } @@ -1412,14 +1415,21 @@ i915_gem_execbuffer2(struct drm_device *dev, void *data, ret = i915_gem_do_execbuffer(dev, data, file, args, exec2_list); if (!ret) { /* Copy the new buffer offsets back to the user's exec list. */ - ret = copy_to_user(to_user_ptr(args->buffers_ptr), - exec2_list, - sizeof(*exec2_list) * args->buffer_count); - if (ret) { - ret = -EFAULT; - DRM_DEBUG("failed to copy %d exec entries " - "back to user (%d)\n", - args->buffer_count, ret); + struct drm_i915_gem_exec_object2 *user_exec_list = + to_user_ptr(args->buffers_ptr); + int i; + + for (i = 0; i < args->buffer_count; i++) { + ret = __copy_to_user(&user_exec_list[i].offset, + &exec2_list[i].offset, + sizeof(user_exec_list[i].offset)); + if (ret) { + ret = -EFAULT; + DRM_DEBUG("failed to copy %d exec entries " + "back to user\n", + args->buffer_count); + break; + } } }