From patchwork Mon Jan 18 18:03:34 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Christian_K=C3=B6nig?= X-Patchwork-Id: 12027969 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=-13.5 required=3.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED,DKIM_INVALID,DKIM_SIGNED,FREEMAIL_FORGED_FROMDOMAIN, FREEMAIL_FROM,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,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 02317C433DB for ; Mon, 18 Jan 2021 18:03:48 +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 B124D22BEA for ; Mon, 18 Jan 2021 18:03:47 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B124D22BEA Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com 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 116C46E563; Mon, 18 Jan 2021 18:03:45 +0000 (UTC) Received: from mail-ed1-x529.google.com (mail-ed1-x529.google.com [IPv6:2a00:1450:4864:20::529]) by gabe.freedesktop.org (Postfix) with ESMTPS id B7C576E454 for ; Mon, 18 Jan 2021 18:03:41 +0000 (UTC) Received: by mail-ed1-x529.google.com with SMTP id g1so17931179edu.4 for ; Mon, 18 Jan 2021 10:03:41 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:subject:date:message-id:in-reply-to:references:mime-version :content-transfer-encoding; bh=VE5dS/K6+mlA/xDSWx/xrkP+6TV7zHaZLCQABHwVPBc=; b=niIgAQftt+iRc9Z5Rd0ZBVUIJw+UnBiAL1ORdEAfqHO9a3jOkKW/kVL/UQJf3qOkiT aQuAMpm4E8xW0tAf+FTZhBcS8TpfwbxbMHmtQvV6ox9DjnFFkpHa/JKdk+xwsHj9Qj+D cM8SLBciAm3LEIcZKQpCr1tQ/WaAlYG2wKbkB04LYXwoxacAgZLi7VtgwrRAKD2A7HrS 7S7FGTCZuhB1FIMEgUg4dvnL9kt3D/cvHKofVbYo8nGxBBGMEk2Gc/u/YoVJ9MHfSQnp Nhf/onJWCx/BAjrrtB5CaACnqxsTPDzlW8F0r4mH5Z40zPMQtA99bhdLoFeHYjDZ4ego e1Gg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=VE5dS/K6+mlA/xDSWx/xrkP+6TV7zHaZLCQABHwVPBc=; b=aEQJYJNWqOrUsNzJ2feIfx/MD1bViiSmPJ+6BG+tGzkn9wcO/7W+koHl9O+BtmvV16 8nm/6f+DeeFaLZ+PIJs43T/edFbeVVfOEG6CWKMZFGaXL2j7dWMv3txxRtHNyuE9sjq+ QotIU2h3qEJaXJQW4OoiZUZLgPAAS0jyqi304II5IGSg+JZDgx2P3CvJNrJ56GtmK0BS Kz46mC4Wv1x+IeKgo/z7vo5g1SlPvi3rG4qju4LXHA7eU4BWrVlLGwBvWRJmo+OpM0o/ UyNhL3s4i8OSAQKIRcGyght0cXtrmc2WUtB30HkIvKFKQ3EQAj7OTDZyUsXD0OqlPibm /ccg== X-Gm-Message-State: AOAM532RKQK9sLtWpfnV+RW8hFFDCLpnbWurHfqHW+xKxCu/MvdjwivC Uu3d83cKS6Vr1CCADTDLHkzl58Aj60c= X-Google-Smtp-Source: ABdhPJzjLHgUaYzajBP6OisVZojLERChVEt+qJ0CvomcPa+ueUUtHlwwBcFkDZX4N3CTwjnZZqvZ3w== X-Received: by 2002:a05:6402:3116:: with SMTP id dc22mr480138edb.325.1610993020444; Mon, 18 Jan 2021 10:03:40 -0800 (PST) Received: from abel.fritz.box ([2a02:908:1252:fb60:4449:7b65:bfa0:95f5]) by smtp.gmail.com with ESMTPSA id x5sm10651160edi.35.2021.01.18.10.03.39 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 18 Jan 2021 10:03:39 -0800 (PST) From: " =?utf-8?q?Christian_K=C3=B6nig?= " X-Google-Original-From: =?utf-8?q?Christian_K=C3=B6nig?= To: daniel@ffwll.ch, peterz@infradead.org, mingo@redhat.com, will@kernel.org, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org Subject: [PATCH] drm/syncobj: make lockdep complain on WAIT_FOR_SUBMIT v2 Date: Mon, 18 Jan 2021 19:03:34 +0100 Message-Id: <20210118180334.43714-2-christian.koenig@amd.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20210118180334.43714-1-christian.koenig@amd.com> References: <20210118180334.43714-1-christian.koenig@amd.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" DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT can't be used when we hold locks since we are basically waiting for userspace to do something. Holding a lock while doing so can trivial deadlock with page faults etc... So make lockdep complain when a driver tries to do this. v2: Add lockdep_assert_none_held() macro. Signed-off-by: Christian König --- drivers/gpu/drm/drm_syncobj.c | 7 +++++++ include/linux/lockdep.h | 5 +++++ 2 files changed, 12 insertions(+) diff --git a/drivers/gpu/drm/drm_syncobj.c b/drivers/gpu/drm/drm_syncobj.c index 6e74e6745eca..f51458615158 100644 --- a/drivers/gpu/drm/drm_syncobj.c +++ b/drivers/gpu/drm/drm_syncobj.c @@ -387,6 +387,13 @@ int drm_syncobj_find_fence(struct drm_file *file_private, if (!syncobj) return -ENOENT; + /* Waiting for userspace with locks help is illegal cause that can + * trivial deadlock with page faults for example. Make lockdep complain + * about it early on. + */ + if (flags & DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT) + lockdep_assert_none_held_once(); + *fence = drm_syncobj_fence_get(syncobj); drm_syncobj_put(syncobj); diff --git a/include/linux/lockdep.h b/include/linux/lockdep.h index b9e9adec73e8..6eb117c0d0f3 100644 --- a/include/linux/lockdep.h +++ b/include/linux/lockdep.h @@ -310,6 +310,10 @@ extern void lock_unpin_lock(struct lockdep_map *lock, struct pin_cookie); WARN_ON_ONCE(debug_locks && !lockdep_is_held(l)); \ } while (0) +#define lockdep_assert_none_held_once() do { \ + WARN_ON_ONCE(debug_locks && current->lockdep_depth); \ + } while (0) + #define lockdep_recursing(tsk) ((tsk)->lockdep_recursion) #define lockdep_pin_lock(l) lock_pin_lock(&(l)->dep_map) @@ -387,6 +391,7 @@ extern int lockdep_is_held(const void *); #define lockdep_assert_held_write(l) do { (void)(l); } while (0) #define lockdep_assert_held_read(l) do { (void)(l); } while (0) #define lockdep_assert_held_once(l) do { (void)(l); } while (0) +#define lockdep_assert_none_held_once() do { } while (0) #define lockdep_recursing(tsk) (0)