From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E144BC282C8 for ; Mon, 28 Jan 2019 17:52:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id AF22E20881 for ; Mon, 28 Jan 2019 17:52:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1548697977; bh=4f6PF922jSX8/OFpN44E86hy3HF0IvgZoNTBmwfcvoc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=GW7gKpe2MWTFjagAoi7x3q4toYXavg4FoF+pO/mWDQiFtEZFKNxZSDAgPWtGVKW7R 8FGrF8GnkiQTNhwwq/zu9Mxt09CgrDgSqt6IAz4ZAQenJ+ydbuwHPxbm4mz1Y/mCdX FlvHPF//a62c+AUCt5eiZwhyPpDBGz54iRhyRRDE= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727022AbfA1Pns (ORCPT ); Mon, 28 Jan 2019 10:43:48 -0500 Received: from mail.kernel.org ([198.145.29.99]:56920 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726647AbfA1Pnp (ORCPT ); Mon, 28 Jan 2019 10:43:45 -0500 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id F10CA21738; Mon, 28 Jan 2019 15:43:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1548690224; bh=4f6PF922jSX8/OFpN44E86hy3HF0IvgZoNTBmwfcvoc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=C/PNiJ0e24uSHSx2/F4+nN+yxrBHMNIMgVkbslRKFjVJQbRmA6dUnsEu99jL/Mley +9PhgfX+YjjApOcUtKOWnN5d69fvmcUPRaANkhXdzu7aowtFV+9szVGVTDiu5WlUVl DB/r5rwfi93l/bpm05vElHX3r01eQ1seOCL9Kcsc= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Eric Anholt , Sasha Levin Subject: [PATCH AUTOSEL 4.20 002/304] drm/v3d: Fix a use-after-free race accessing the scheduler's fences. Date: Mon, 28 Jan 2019 10:38:39 -0500 Message-Id: <20190128154341.47195-2-sashal@kernel.org> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20190128154341.47195-1-sashal@kernel.org> References: <20190128154341.47195-1-sashal@kernel.org> MIME-Version: 1.0 X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Eric Anholt [ Upstream commit 34c2c4f632f232ed2fdb66d4e42cc72d322273fe ] Once we push the job, the scheduler could run it and free it. So, if we want to reference their fences, we need to grab them before then. I haven't seen this happen in many days of conformance test runtime, but let's still close the race. Signed-off-by: Eric Anholt Fixes: 57692c94dcbe ("drm/v3d: Introduce a new DRM driver for Broadcom V3D V3.x+") Link: https://patchwork.freedesktop.org/patch/254119/ Reviewed-by: Boris Brezillon Signed-off-by: Sasha Levin --- drivers/gpu/drm/v3d/v3d_drv.h | 5 +++++ drivers/gpu/drm/v3d/v3d_gem.c | 8 ++++++-- 2 files changed, 11 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/v3d/v3d_drv.h b/drivers/gpu/drm/v3d/v3d_drv.h index e6fed696ad86..cbe5be0c47eb 100644 --- a/drivers/gpu/drm/v3d/v3d_drv.h +++ b/drivers/gpu/drm/v3d/v3d_drv.h @@ -198,6 +198,11 @@ struct v3d_exec_info { */ struct dma_fence *bin_done_fence; + /* Fence for when the scheduler considers the render to be + * done, for when the BOs reservations should be complete. + */ + struct dma_fence *render_done_fence; + struct kref refcount; /* This is the array of BOs that were looked up at the start of exec. */ diff --git a/drivers/gpu/drm/v3d/v3d_gem.c b/drivers/gpu/drm/v3d/v3d_gem.c index 70c54774400b..2814c72cb090 100644 --- a/drivers/gpu/drm/v3d/v3d_gem.c +++ b/drivers/gpu/drm/v3d/v3d_gem.c @@ -209,7 +209,7 @@ v3d_flush_caches(struct v3d_dev *v3d) static void v3d_attach_object_fences(struct v3d_exec_info *exec) { - struct dma_fence *out_fence = &exec->render.base.s_fence->finished; + struct dma_fence *out_fence = exec->render_done_fence; struct v3d_bo *bo; int i; @@ -409,6 +409,7 @@ v3d_exec_cleanup(struct kref *ref) dma_fence_put(exec->render.done_fence); dma_fence_put(exec->bin_done_fence); + dma_fence_put(exec->render_done_fence); for (i = 0; i < exec->bo_count; i++) drm_gem_object_put_unlocked(&exec->bo[i]->base); @@ -572,6 +573,9 @@ v3d_submit_cl_ioctl(struct drm_device *dev, void *data, if (ret) goto fail_unreserve; + exec->render_done_fence = + dma_fence_get(&exec->render.base.s_fence->finished); + kref_get(&exec->refcount); /* put by scheduler job completion */ drm_sched_entity_push_job(&exec->render.base, &v3d_priv->sched_entity[V3D_RENDER]); @@ -585,7 +589,7 @@ v3d_submit_cl_ioctl(struct drm_device *dev, void *data, sync_out = drm_syncobj_find(file_priv, args->out_sync); if (sync_out) { drm_syncobj_replace_fence(sync_out, 0, - &exec->render.base.s_fence->finished); + exec->render_done_fence); drm_syncobj_put(sync_out); } -- 2.19.1