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 D40CAC433FE for ; Wed, 23 Nov 2022 08:33:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236166AbiKWIdv (ORCPT ); Wed, 23 Nov 2022 03:33:51 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42508 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229472AbiKWIdt (ORCPT ); Wed, 23 Nov 2022 03:33:49 -0500 Received: from mail-lf1-x134.google.com (mail-lf1-x134.google.com [IPv6:2a00:1450:4864:20::134]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AB941E0B44 for ; Wed, 23 Nov 2022 00:33:48 -0800 (PST) Received: by mail-lf1-x134.google.com with SMTP id c1so27113425lfi.7 for ; Wed, 23 Nov 2022 00:33:48 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=mime-version:references:in-reply-to:message-id:subject:cc:to:from :date:from:to:cc:subject:date:message-id:reply-to; bh=GP8l1iGGwn4fXZb322yNmXnMhiWxUfGRTbBa+6nT3ag=; b=grLXygJZO0Bx8iiadWbvlKJmmflKTxZ5vzxphVjLy81hMM1SgiQzoo0Shg5BZVXx/F da240dF2jq2j4Xp8zhJTt1v1Jp2vVfQQmzJEFar5V/atAsnyb3GcT/KJL6W1fvHu1nW8 yw+r3yFPUSqyC6iH0gRMvHdIGp68AvndzFoWLI5ly0HDfvbESRyJzKKJGfmNjBTiKPRY MAjRWilMYt0kEY66xv3G13NkdGJKnX0Myfa3Xdv/CVzu3UAG96GERGexZo/vVFqtGj7W dbqaz/9Bn9UKFTv8CDXCNPVox0sk3G+lAWuuapn8n2/IR9asGZqZbBzzVKA6EbidNFOo dDEg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=mime-version:references:in-reply-to:message-id:subject:cc:to:from :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=GP8l1iGGwn4fXZb322yNmXnMhiWxUfGRTbBa+6nT3ag=; b=3vjcWhXsLZzyLznenKIxCcMgglXzwgjiIbWRM1jrJ9Ohy5H+02Vph1VzDKv141/qlB iw0d+YMl67oM36Dpb9eZ4l0wKRf3tZi+DWmwQ2sr4Ca3N+Hv8cEHBrhHbTjwFt1bkGdr Yr9TWe/V2rl5TlVVZNsQMO82D24JrPJSe7gVxyVAmg99IWPfkQ/HrHKgJxWoWFhwLIn8 ulgGZUUFp415OtjK7zcWgA7Fld7zspKwzFRzSVFekTk0jjaCqyK6XqmSa1qW2BQY5c3f hdSy/3PdOYBF5MiAI71WG/KmNJq/e0+ULlDQBUPpFF/eBaBdWwKqtWU4MzvNGxKOyqKY hy5Q== X-Gm-Message-State: ANoB5pmkpNMwMMvty8ON1qyUuV7ciuUdndJmwhsnNpJrsQJ+PsEAeXSW osTHOilKiOo8+Na1Cg+CmKo= X-Google-Smtp-Source: AA0mqf4IYpzUuisugu07V7ZumpJ7U+9y3CR2RHG/v3U5LmMwrWA44BlVBzqXWZzDZxlQVrY6JNPJDA== X-Received: by 2002:a19:ca1b:0:b0:4a7:7d62:2807 with SMTP id a27-20020a19ca1b000000b004a77d622807mr10479283lfg.77.1669192427925; Wed, 23 Nov 2022 00:33:47 -0800 (PST) Received: from eldfell ([194.136.85.206]) by smtp.gmail.com with ESMTPSA id p24-20020a2ea4d8000000b002790d8012cfsm2121782ljm.139.2022.11.23.00.33.47 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 23 Nov 2022 00:33:47 -0800 (PST) Date: Wed, 23 Nov 2022 10:33:38 +0200 From: Pekka Paalanen To: Christian =?UTF-8?B?S8O2bmln?= Cc: Daniel Vetter , Rob Clark , Nicolas Dufresne , Tomasz Figa , Lucas Stach , Daniel Stone , sumit.semwal@linaro.org, dri-devel@lists.freedesktop.org, linaro-mm-sig@lists.linaro.org, linux-media@vger.kernel.org Subject: Re: Try to address the DMA-buf coherency problem Message-ID: <20221123103338.238571e1@eldfell> In-Reply-To: References: <4fa4e5d3b1f46e46139bad069cbf5e795e63afa8.camel@pengutronix.de> <0abc6efddb8dfc1888de15a1bedaaac6688fd078.camel@pengutronix.de> <1e2a6750-9849-e9ee-69d6-e4bfdcfb64f3@gmail.com> <346d6ad023ef8697aafd93ac1b100890f3637e44.camel@ndufresne.ca> X-Mailer: Claws Mail 3.17.8 (GTK+ 2.24.33; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: multipart/signed; boundary="Sig_/cajiis7amej/mZobkBvjUIf"; protocol="application/pgp-signature"; micalg=pgp-sha256 Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org --Sig_/cajiis7amej/mZobkBvjUIf Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable On Tue, 22 Nov 2022 18:33:59 +0100 Christian K=C3=B6nig wrote: > We should have come up with dma-heaps earlier and make it clear that=20 > exporting a DMA-buf from a device gives you something device specific=20 > which might or might not work with others. >=20 > Apart from that I agree, DMA-buf should be capable of handling this.=20 > Question left is what documentation is missing to make it clear how=20 > things are supposed to work? Perhaps somewhat related from Daniel Stone that seems to have been forgotten: https://lore.kernel.org/dri-devel/20210905122742.86029-1-daniels@collabora.= com/ It aimed mostly at userspace, but sounds to me like the coherency stuff could use a section of its own there? 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