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=-3.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 24D6DC4320E for ; Tue, 31 Aug 2021 17:19:44 +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 EEBC7611F2 for ; Tue, 31 Aug 2021 17:19:41 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org EEBC7611F2 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-m68k.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id D75566E086; Tue, 31 Aug 2021 17:19:40 +0000 (UTC) Received: from mail-vs1-f41.google.com (mail-vs1-f41.google.com [209.85.217.41]) by gabe.freedesktop.org (Postfix) with ESMTPS id 3D9DC6E086 for ; Tue, 31 Aug 2021 17:19:40 +0000 (UTC) Received: by mail-vs1-f41.google.com with SMTP id d6so124696vsr.7 for ; Tue, 31 Aug 2021 10:19:40 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=UMOX2To1IEOY2ZnzUeCxb0+BBk/jcmCPbhrdDzxJbcg=; b=nk396mGmiStqAA3qvD2bczCi0HNpqRDYYx1EZBXDTqtGgqFxbmrC43phUmJbbXrgT+ v6Cw1HMYSPIO7Hfr2rOZuvqm9XF5+byV9wSXoJDs9BxTKgWFYKURCbTsUMUX5vYiAYUn Q5vlVHIBvStX/RfB0EXw3kMysXzN0oPQw83CxQ/b2c8LTIe/uengAVh6xg2N3XVai3DT HxsBPmlL/07nogyEAxl0jfDK/YADIMDtuq+7axHBQOmOntmTDMRhzMaNq3ZXw28AAvyt S6dOgiPJUtPwP1yKbWvep1KwYq2hOaDm+ZUEEoH1siMa/eUFcs7ASf34OIc91cQDjGTY VoDw== X-Gm-Message-State: AOAM531Q/pw4jQBqmMLakUvdF2Z5v6BAV0E7WYgcPToHDlYPA/oiIc2g q9/imUNe/r5+eXhf+x2NIoeOxQ+zCUyDJMnU/VA= X-Google-Smtp-Source: ABdhPJzwIcYtEYXT+4ELrSXZhc7SGBnDBykZ6QWPifjhJFCJ02Jh+wK9QnEW6KWY0HcJvsALfiP7/h+mMWcZEJ7eWpI= X-Received: by 2002:a67:c789:: with SMTP id t9mr20435604vsk.60.1630430379297; Tue, 31 Aug 2021 10:19:39 -0700 (PDT) MIME-Version: 1.0 References: <000000000000815b9605c70e74f8@google.com> <131b24e5-ee31-6f7b-42b4-c34583711913@infradead.org> <2fccb5d3-191c-924e-159f-1c9d423e282f@i-love.sakura.ne.jp> <339bfb21-8e80-c7d9-46dd-c416f87c50c0@infradead.org> <535e404d-03bf-8e7a-b296-132a2a98c599@i-love.sakura.ne.jp> <5c6d2b95-31d7-0d59-5e62-2593d9a0e1fe@i-love.sakura.ne.jp> In-Reply-To: <5c6d2b95-31d7-0d59-5e62-2593d9a0e1fe@i-love.sakura.ne.jp> From: Geert Uytterhoeven Date: Tue, 31 Aug 2021 19:19:27 +0200 Message-ID: Subject: Re: [PATCH] fbmem: don't allow too huge resolutions To: Tetsuo Handa Cc: Daniel Vetter , syzbot , Andrew Morton , Bartlomiej Zolnierkiewicz , Colin King , DRI Development , Linux Fbdev development list , Linux Kernel Mailing List , Masahiro Yamada , syzkaller-bugs@googlegroups.com, Randy Dunlap Content-Type: text/plain; charset="UTF-8" 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" Hi Handa-san, On Tue, Aug 31, 2021 at 5:24 PM Tetsuo Handa wrote: > On 2021/08/31 15:48, Geert Uytterhoeven wrote: > > Furthermore, this restricts the virtual frame buffer size on 64-bit, > > too, while graphics cards can have much more than 4 GiB of RAM. > > Excuse me, but do you mean that some hardware allows allocating more than > UINT_MAX bytes of memory for kernel frame buffer drivers? While smem_len is u32 (there have been complaints about such limitations on 64-bit platforms as far as 10 years ago), I see no reason why a graphics card with more than 4 GiB of RAM would not be able to provide a very large virtual screen. Of course e.g. vga16fb cannot, as it is limited to 64 KiB. Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds