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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id C3B11C43217 for ; Mon, 7 Nov 2022 17:38:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232943AbiKGRiA (ORCPT ); Mon, 7 Nov 2022 12:38:00 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49068 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232901AbiKGRh6 (ORCPT ); Mon, 7 Nov 2022 12:37:58 -0500 Received: from madras.collabora.co.uk (madras.collabora.co.uk [46.235.227.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DED682126C; Mon, 7 Nov 2022 09:37:57 -0800 (PST) Received: from [192.168.2.123] (109-252-117-140.nat.spd-mgts.ru [109.252.117.140]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: dmitry.osipenko) by madras.collabora.co.uk (Postfix) with ESMTPSA id AB1B366023A6; Mon, 7 Nov 2022 17:37:51 +0000 (GMT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=collabora.com; s=mail; t=1667842676; bh=UMRS4vM/GE6IwT0ij75XZK2yxYOoTzS0D0RuPVqVLQ0=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=miwcwDXpS7Bbvd1kg8ufWW8EYMDu/fgcPle5PVDEc/B45ktlgqIx4KYYA7QJIH0/S by6GLLPhco/tY89MPdmT/s8ECZUVpumdsyezUNadhVFrBlk2dKSnpRR4YYHs5ifRqx kuVjLNaEObN6eE/lFu1N0kKKLb+Hg6OZXx6pYEFM8ctFWBT+AgibmceYq8kqFMCEG5 kowqpdeAKxf0CNu91SEfqgK2XcDJWq/xRLM5BkdsTv9wWssGJ9nsGOSCQkZma8qL+/ vHXhwraRJ7N/LdEZD26enrecVwg8djUWKheSt++aa2448mbVzh/odGXyBvPK2wEDIp kG1p1Gc0TCNDw== Message-ID: Date: Mon, 7 Nov 2022 20:37:49 +0300 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.3.1 Subject: Re: [PATCH v7 18/21] dma-buf: Move dma_buf_mmap() to dynamic locking specification Content-Language: en-US To: Daniel Vetter Cc: David Airlie , Gerd Hoffmann , Gurchetan Singh , Chia-I Wu , Daniel Almeida , Gert Wollny , Gustavo Padovan , Daniel Stone , Tomeu Vizoso , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , Rob Clark , Sumit Semwal , =?UTF-8?Q?Christian_K=c3=b6nig?= , "Pan, Xinhui" , Thierry Reding , Tomasz Figa , Marek Szyprowski , Mauro Carvalho Chehab , Alex Deucher , Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , Tvrtko Ursulin , =?UTF-8?Q?Thomas_Hellstr=c3=b6m?= , Qiang Yu , Srinivas Kandagatla , Amol Maheshwari , Jason Gunthorpe , Leon Romanovsky , Juergen Gross , Stefano Stabellini , Oleksandr Tyshchenko , Tomi Valkeinen , Russell King , Lucas Stach , Christian Gmeiner , Ruhl Michael J , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, Dmitry Osipenko , linux-media@vger.kernel.org, linaro-mm-sig@lists.linaro.org, amd-gfx@lists.freedesktop.org, intel-gfx@lists.freedesktop.org, kernel@collabora.com, virtualization@lists.linux-foundation.org, linux-rdma@vger.kernel.org, linux-arm-msm@vger.kernel.org References: <20221017172229.42269-1-dmitry.osipenko@collabora.com> <20221017172229.42269-19-dmitry.osipenko@collabora.com> From: Dmitry Osipenko In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 11/7/22 20:25, Daniel Vetter wrote: >> Move dma_buf_mmap() function to the dynamic locking specification by >> taking the reservation lock. Neither of the today's drivers take the >> reservation lock within the mmap() callback, hence it's safe to enforce >> the locking. >> >> Acked-by: Sumit Semwal >> Acked-by: Christian König >> Signed-off-by: Dmitry Osipenko > Just noticed this while reading code ... this patch seems to have > missed dma_buf_mmap_internal()? > > Might be good if at least some drivers gain a dma_resv_assert_held in > that path to make sure we're not quite this bad, together with fixing > this issue. Good catch! I'll prepare the patches. -- Best regards, Dmitry