From patchwork Thu Jul 23 17:21:17 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chris Wilson X-Patchwork-Id: 11681401 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 C4B0513B1 for ; Thu, 23 Jul 2020 17:21:43 +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 AB92820714 for ; Thu, 23 Jul 2020 17:21:43 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org AB92820714 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=chris-wilson.co.uk 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 66BDD6E2A0; Thu, 23 Jul 2020 17:21:36 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from fireflyinternet.com (unknown [77.68.26.236]) by gabe.freedesktop.org (Postfix) with ESMTPS id 404916E260; Thu, 23 Jul 2020 17:21:35 +0000 (UTC) X-Default-Received-SPF: pass (skip=forwardok (res=PASS)) x-ip-name=78.156.65.138; Received: from build.alporthouse.com (unverified [78.156.65.138]) by fireflyinternet.com (Firefly Internet (M1)) with ESMTP id 21910647-1500050 for multiple; Thu, 23 Jul 2020 18:21:21 +0100 From: Chris Wilson To: intel-gfx@lists.freedesktop.org Subject: [PATCH 1/3] drm: Restore driver.preclose() for all to use Date: Thu, 23 Jul 2020 18:21:17 +0100 Message-Id: <20200723172119.17649-1-chris@chris-wilson.co.uk> 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: , Cc: stable@vger.kernel.org, Chris Wilson , Gustavo Padovan , CQ Tang , dri-devel@lists.freedesktop.org, Daniel Vetter Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" An unfortunate sequence of events, but it turns out there is a valid usecase for being able to free/decouple the driver objects before they are freed by the DRM core. In particular, if we have a pointer into a drm core object from inside a driver object, that pointer needs to be nerfed *before* it is freed so that concurrent access (e.g. debugfs) does not following the dangling pointer. The legacy marker was adding in the code movement from drp_fops.c to drm_file.c References: 9acdac68bcdc ("drm: rename drm_fops.c to drm_file.c") Signed-off-by: Chris Wilson Cc: Daniel Vetter Cc: Gustavo Padovan Cc: CQ Tang Cc: # v4.12+ --- drivers/gpu/drm/drm_file.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/gpu/drm/drm_file.c b/drivers/gpu/drm/drm_file.c index 0ac4566ae3f4..7b4258d6f7cc 100644 --- a/drivers/gpu/drm/drm_file.c +++ b/drivers/gpu/drm/drm_file.c @@ -258,8 +258,7 @@ void drm_file_free(struct drm_file *file) (long)old_encode_dev(file->minor->kdev->devt), atomic_read(&dev->open_count)); - if (drm_core_check_feature(dev, DRIVER_LEGACY) && - dev->driver->preclose) + if (dev->driver->preclose) dev->driver->preclose(dev, file); if (drm_core_check_feature(dev, DRIVER_LEGACY))