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=-5.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT autolearn=no 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 6C534C4320A for ; Wed, 1 Sep 2021 12:02:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 57BBC60724 for ; Wed, 1 Sep 2021 12:02:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S243928AbhIAMDq (ORCPT ); Wed, 1 Sep 2021 08:03:46 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51560 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S243901AbhIAMDo (ORCPT ); Wed, 1 Sep 2021 08:03:44 -0400 Received: from mail-wr1-x42f.google.com (mail-wr1-x42f.google.com [IPv6:2a00:1450:4864:20::42f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7B5B3C061575 for ; Wed, 1 Sep 2021 05:02:47 -0700 (PDT) Received: by mail-wr1-x42f.google.com with SMTP id i6so4171362wrv.2 for ; Wed, 01 Sep 2021 05:02:47 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=uNWyDCJRg5z+YdrGcz6ue9XUC2vcsZfH2SlJlbhPC2Y=; b=AwP8q6IrhVvt2OCuxNZ/CQ4Mh1qUju3OY1uhxDDlpjAUg60KvC5+b7vLsLmr99gHAk MBTR4BANx4JWZEv1QTzkOClDEc0JuQJmM197nifSno8nN2fCH7ttK2FdPByOADQu+MFN VAbXFQFhuy7Z4D6AD2vg53f/l9edv7gFVjFQ9k/Eg73EFwDsv8GGZAI6t2sty6wo3uE8 xMwbYQIMWT6gAKNASr08ZvriQwt9PUfmMuwB17kqOEkS89reM28JOoRDQROztjY4s90Q vQV7f4yMl94jJY9kgRDxpb+PCslEMi6l3555vaalpX+iS81+VA9t+XzU1O5Ukyb0LeRe Wg3Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=uNWyDCJRg5z+YdrGcz6ue9XUC2vcsZfH2SlJlbhPC2Y=; b=rj9XwFZV8PQHxVPFkYTy4HbxwoL4epAFXcmb1TULVND1Hh38DXspvPt3LSJyNijsqd ii9yxq/n8Gz+kO8dVGLEeKYyd6UuGRIo1hVlcfo1CgdjBhd+WlEFEnMttQu/PnTN+SMM /pV07oZLElG9k98y1D9/wcws4S+8G4JGdPJSuGMJK+S5341wj2a8HTtZnV/l6z7ryB51 FQ7IoohBYRCqS/6FUSeexv5Ifipp0a/SKG731kArZD50NpE9g6C4XkzNJjVU/98Jm9e+ oQoBM+d7Ud69uEBO656f7DFDxLRSAKgvLMWprAqYo1UcgRpkfqGJ8ytACe6AVHm7m996 vQOw== X-Gm-Message-State: AOAM530+OhJ5CWV8WWcy9lavlWEv4iTB5+ltmPDnntErL+EPzgBN1Qsl II0SVj3+JBTqyafSgXkidwo= X-Google-Smtp-Source: ABdhPJwW/P17cLcvURrVKCOBQEktzDGC95e0OV9bMzMpRbkF9G1qN1z/I0VT8R05Fg8+WL7oGKrbKQ== X-Received: by 2002:adf:b745:: with SMTP id n5mr38295873wre.338.1630497766169; Wed, 01 Sep 2021 05:02:46 -0700 (PDT) Received: from abel.fritz.box (p5b0ea1b5.dip0.t-ipconnect.de. [91.14.161.181]) by smtp.gmail.com with ESMTPSA id l7sm5641336wmj.9.2021.09.01.05.02.45 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 01 Sep 2021 05:02:45 -0700 (PDT) From: "=?UTF-8?q?Christian=20K=C3=B6nig?=" X-Google-Original-From: =?UTF-8?q?Christian=20K=C3=B6nig?= To: dri-devel@lists.freedesktop.org Cc: daniel@ffwll.ch, linux-media@vger.kernel.org, linaro-mm-sig@lists.linaro.org Subject: Harden the dma-fence documentation a bit more Date: Wed, 1 Sep 2021 14:02:38 +0200 Message-Id: <20210901120240.7339-1-christian.koenig@amd.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org Hi guys, while it is in most cases technically possible to not have a reference to the dma_fence when adding a callback it is usually a good idea to make sure to always have a reference anyway. Otherwise we can indeed see cases where this doesn't really work as intended like for example in the now fixed EPOLL code. Regards, Christian.