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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED,USER_AGENT_MUTT 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 A6E70C71122 for ; Sun, 14 Oct 2018 00:11:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7320E20859 for ; Sun, 14 Oct 2018 00:11:08 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7320E20859 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726411AbeJNHuE (ORCPT ); Sun, 14 Oct 2018 03:50:04 -0400 Received: from mx1.redhat.com ([209.132.183.28]:48358 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726042AbeJNHuD (ORCPT ); Sun, 14 Oct 2018 03:50:03 -0400 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 77C5EC05D3FF; Sun, 14 Oct 2018 00:11:06 +0000 (UTC) Received: from asgard.redhat.com (ovpn-200-28.brq.redhat.com [10.40.200.28]) by smtp.corp.redhat.com (Postfix) with ESMTPS id E93F95EB18; Sun, 14 Oct 2018 00:11:04 +0000 (UTC) Date: Sun, 14 Oct 2018 02:11:26 +0200 From: Eugene Syromiatnikov To: tbhardwa@codeaurora.org Cc: "'Zhang, Ning A'" , linux-kernel@vger.kernel.org, linux-media@vger.kernel.org Subject: Re: question about V4L2_MEMORY_USERPTR on 64bit applications Message-ID: <20181014001126.GA717@asgard.redhat.com> References: <1539313441.21249.3.camel@intel.com> <1539318782.21249.7.camel@intel.com> <000601d461eb$a1f7afc0$e5e70f40$@codeaurora.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <000601d461eb$a1f7afc0$e5e70f40$@codeaurora.org> User-Agent: Mutt/1.5.23 (2014-03-12) X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.32]); Sun, 14 Oct 2018 00:11:06 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Oct 12, 2018 at 10:52:51AM +0530, tbhardwa@codeaurora.org wrote: > (in 64 bit userspace long is 32-bit) Not on Linux. $ cat /tmp/c.c int main(void) { return sizeof(long); } $ gcc /tmp/c.c $ ./a.out; echo $? 8 $ file ./a.out ./a.out: ELF 64-bit LSB pie executable, 64-bit PowerPC or cisco 7500, version 1 (SYSV), dynamically linked, interpreter /lib64/ld64.so.2, for GNU/Linux 3.10.0, BuildID[sha1]=dad78822e741b7900dc7568222822d5d63c31a6c, not stripped