From patchwork Wed Jan 16 04:28:01 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dave Airlie X-Patchwork-Id: 1986461 Return-Path: X-Original-To: patchwork-dri-devel@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork2.kernel.org Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) by patchwork2.kernel.org (Postfix) with ESMTP id 3FC0DDF2A2 for ; Wed, 16 Jan 2013 04:29:42 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id EBCFDE65D3 for ; Tue, 15 Jan 2013 20:29:41 -0800 (PST) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28]) by gabe.freedesktop.org (Postfix) with ESMTP id 41FE0E603C for ; Tue, 15 Jan 2013 20:28:04 -0800 (PST) Received: from int-mx01.intmail.prod.int.phx2.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id r0G4S3MO029224 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Tue, 15 Jan 2013 23:28:03 -0500 Received: from prime.bne.redhat.com (dhcp-40-183.bne.redhat.com [10.64.40.183]) by int-mx01.intmail.prod.int.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id r0G4S1hI031098 for ; Tue, 15 Jan 2013 23:28:03 -0500 From: Dave Airlie To: dri-devel@lists.freedesktop.org Subject: [PATCH] ttm: don't destroy old mm_node on memcpy failure Date: Wed, 16 Jan 2013 14:28:01 +1000 Message-Id: <1358310481-15123-1-git-send-email-airlied@gmail.com> X-Scanned-By: MIMEDefang 2.67 on 10.5.11.11 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: dri-devel-bounces+patchwork-dri-devel=patchwork.kernel.org@lists.freedesktop.org Errors-To: dri-devel-bounces+patchwork-dri-devel=patchwork.kernel.org@lists.freedesktop.org When we are using memcpy to move objects around, and we fail to memcpy due to lack of memory to populate or failure to finish the copy, we don't want to destroy the mm_node that has been copied into old_copy. While working on a new kms driver that uses memcpy, if I overallocated bo's up to the memory limits, and eviction failed, then machine would oops soon after due to having an active bo with an already freed drm_mm embedded in it, freeing it a second time didn't end well. Signed-off-by: Dave Airlie Reviewed-by: Jerome Glisse --- drivers/gpu/drm/ttm/ttm_bo_util.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/ttm/ttm_bo_util.c b/drivers/gpu/drm/ttm/ttm_bo_util.c index ed42323..a2aab88 100644 --- a/drivers/gpu/drm/ttm/ttm_bo_util.c +++ b/drivers/gpu/drm/ttm/ttm_bo_util.c @@ -344,8 +344,12 @@ int ttm_bo_move_memcpy(struct ttm_buffer_object *bo, if (ttm->state == tt_unpopulated) { ret = ttm->bdev->driver->ttm_tt_populate(ttm); - if (ret) + if (ret) { + /* if we fail here don't nuke the mm node + * as the bo still owns it */ + old_copy.mm_node = NULL; goto out1; + } } add = 0; @@ -371,8 +375,11 @@ int ttm_bo_move_memcpy(struct ttm_buffer_object *bo, prot); } else ret = ttm_copy_io_page(new_iomap, old_iomap, page); - if (ret) + if (ret) { + /* failing here, means keep old copy as-is */ + old_copy.mm_node = NULL; goto out1; + } } mb(); out2: