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=-0.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, 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 12069C17440 for ; Wed, 13 Nov 2019 00:59:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DEBFB21A49 for ; Wed, 13 Nov 2019 00:59:10 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=intel-com.20150623.gappssmtp.com header.i=@intel-com.20150623.gappssmtp.com header.b="aNNgsrA5" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727241AbfKMA7K (ORCPT ); Tue, 12 Nov 2019 19:59:10 -0500 Received: from mail-ot1-f65.google.com ([209.85.210.65]:41121 "EHLO mail-ot1-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727216AbfKMA7K (ORCPT ); Tue, 12 Nov 2019 19:59:10 -0500 Received: by mail-ot1-f65.google.com with SMTP id 94so125007oty.8 for ; Tue, 12 Nov 2019 16:59:09 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=intel-com.20150623.gappssmtp.com; s=20150623; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=bbhHvXUlpKSBxAaen2slRAaR7FABAWW5b4ZHt5uDQAs=; b=aNNgsrA5EIFA9nVSCXy/uyenu1ifAR2ZxMR/sDW6HqK6vSTYpxIpmBrjP/vDjDaVnk l4xh/AHHGyooUHFp1c42LTwLTpwdgtUaJfWvN3Y7CFSVzmwzvxLUaHQBl+Ibev8TBoid 2FUFgDLM8vD2vOwzS+IEshtyE4Y+b3ieXpqqo3Mxdly/m4ak6FnwfnCLEy5DGwsI7qq9 7rFre8WIcpfUZvKl+y7wQa6yOvynR61ZdKROoMobKwRLP3lkc2bkhgPK6DIYIEcGXZ4p WUPwy1pR33Kp+/7N+4r5VmPuWnlSLsuN14iR6BROP5kh/8NTzRoeUzJllo7I56/tNtvu ttpQ== 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=bbhHvXUlpKSBxAaen2slRAaR7FABAWW5b4ZHt5uDQAs=; b=r5DSAM+1oJ6mlONMZ9d619i6IHXtphuhmU3PDFrHf3zkzgT8Xp8eHzQjFRgSuMSMfH gZswIzja8ZPNQYRE/sn/W/ACTfm8EmzB5bheNMuklJS52vOnzhEiCPqDBbbUrfnFAlXs fZ2UYGjtzicaMS2hPwN1kdndhXcW89VgSA0NnKgTXOcv3grLoFtvbKG35HcB1+b3QyAh J4M0Ff9FQCdYs8ZkBho97rcCFXSpA0GLgURkr95iiPwWLC2Thc5dSjm4j/hwasHsKtho dZ/NEagwd3EVPFaHNCQuDKccTvYOAoeo+3DT6TK9FZsNjZpN3xmnDOrKmaYefhEnbJEQ l+Nw== X-Gm-Message-State: APjAAAXNRGFI6v+hJNtvbSOzLqAT2yvaLlUA8NKmiGSCQeneUFlYINXX rPBMMBCU/paswTgkUCQQ2GDeEWStBHPnp+YsnrJlEA== X-Google-Smtp-Source: APXvYqwE5wMeaGSIvNyY2BTy28AxuQMGsjlQOMQJ/g9Nuz73c9JXx/mbsafhYfzhqVldWgO1VAvXOO9/vT+g3CHkLek= X-Received: by 2002:a05:6830:1b70:: with SMTP id d16mr300372ote.71.1573606748988; Tue, 12 Nov 2019 16:59:08 -0800 (PST) MIME-Version: 1.0 References: <20191112000700.3455038-1-jhubbard@nvidia.com> <20191112000700.3455038-9-jhubbard@nvidia.com> <20191112204338.GE5584@ziepe.ca> <0db36e86-b779-01af-77e7-469af2a2e19c@nvidia.com> <20191112234250.GA19615@ziepe.ca> In-Reply-To: <20191112234250.GA19615@ziepe.ca> From: Dan Williams Date: Tue, 12 Nov 2019 16:58:57 -0800 Message-ID: Subject: Re: [PATCH v3 08/23] vfio, mm: fix get_user_pages_remote() and FOLL_LONGTERM To: Jason Gunthorpe Cc: John Hubbard , Andrew Morton , Al Viro , Alex Williamson , Benjamin Herrenschmidt , =?UTF-8?B?QmrDtnJuIFTDtnBlbA==?= , Christoph Hellwig , Daniel Vetter , Dave Chinner , David Airlie , "David S . Miller" , Ira Weiny , Jan Kara , Jens Axboe , Jonathan Corbet , =?UTF-8?B?SsOpcsO0bWUgR2xpc3Nl?= , Magnus Karlsson , Mauro Carvalho Chehab , Michael Ellerman , Michal Hocko , Mike Kravetz , Paul Mackerras , Shuah Khan , Vlastimil Babka , bpf@vger.kernel.org, Maling list - DRI developers , KVM list , linux-block@vger.kernel.org, Linux Doc Mailing List , linux-fsdevel , linux-kselftest@vger.kernel.org, "Linux-media@vger.kernel.org" , linux-rdma , linuxppc-dev , Netdev , Linux MM , LKML Content-Type: text/plain; charset="UTF-8" Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On Tue, Nov 12, 2019 at 3:43 PM Jason Gunthorpe wrote: > > On Tue, Nov 12, 2019 at 02:45:51PM -0800, Dan Williams wrote: > > On Tue, Nov 12, 2019 at 2:43 PM John Hubbard wrote: > > > > > > On 11/12/19 12:43 PM, Jason Gunthorpe wrote: > > > ... > > > >> - } > > > >> + ret = get_user_pages_remote(NULL, mm, vaddr, 1, flags | FOLL_LONGTERM, > > > >> + page, vmas, NULL); > > > >> + /* > > > >> + * The lifetime of a vaddr_get_pfn() page pin is > > > >> + * userspace-controlled. In the fs-dax case this could > > > >> + * lead to indefinite stalls in filesystem operations. > > > >> + * Disallow attempts to pin fs-dax pages via this > > > >> + * interface. > > > >> + */ > > > >> + if (ret > 0 && vma_is_fsdax(vmas[0])) { > > > >> + ret = -EOPNOTSUPP; > > > >> + put_page(page[0]); > > > >> } > > > > > > > > AFAIK this chunk is redundant now as it is some hack to emulate > > > > FOLL_LONGTERM? So vmas can be deleted too. > > > > > > Let me first make sure I understand what Dan has in mind for the vma > > > checking, in the other thread... > > > > It's not redundant relative to upstream which does not do anything the > > FOLL_LONGTERM in the gup-slow path... but I have not looked at patches > > 1-7 to see if something there made it redundant. > > Oh, the hunk John had below for get_user_pages_remote() also needs to > call __gup_longterm_locked() when FOLL_LONGTERM is specified, then > that calls check_dax_vmas() which duplicates the vma_is_fsdax() check > above. Oh true, good eye. It is redundant if it does additionally call __gup_longterm_locked(), and it needs to do that otherwises it undoes the CMA migration magic that Aneesh added. > > Certainly no caller of FOLL_LONGTERM should have to do dax specific > VMA checking. Agree, that was my comment about cleaning up the vma_is_fsdax() check to be internal to the gup core. 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Tue, 12 Nov 2019 16:59:08 -0800 (PST) MIME-Version: 1.0 References: <20191112000700.3455038-1-jhubbard@nvidia.com> <20191112000700.3455038-9-jhubbard@nvidia.com> <20191112204338.GE5584@ziepe.ca> <0db36e86-b779-01af-77e7-469af2a2e19c@nvidia.com> <20191112234250.GA19615@ziepe.ca> In-Reply-To: <20191112234250.GA19615@ziepe.ca> From: Dan Williams Date: Tue, 12 Nov 2019 16:58:57 -0800 Message-ID: Subject: Re: [PATCH v3 08/23] vfio, mm: fix get_user_pages_remote() and FOLL_LONGTERM To: Jason Gunthorpe Content-Type: text/plain; charset="UTF-8" X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Michal Hocko , Jan Kara , KVM list , Linux Doc Mailing List , David Airlie , Dave Chinner , Maling list - DRI developers , LKML , Linux MM , Paul Mackerras , linux-kselftest@vger.kernel.org, Ira Weiny , Jonathan Corbet , linux-rdma , Christoph Hellwig , Vlastimil Babka , =?UTF-8?B?QmrDtnJuIFTDtnBlbA==?= , "Linux-media@vger.kernel.org" , Shuah Khan , John Hubbard , linux-block@vger.kernel.org, =?UTF-8?B?SsOpcsO0bWUgR2xpc3Nl?= , Al Viro , Mauro Carvalho Chehab , bpf@vger.kernel.org, Magnus Karlsson , Jens Axboe , Netdev , Alex Williamson , Daniel Vetter , linux-fsdevel , Andrew Morton , linuxppc-dev , "David S . Miller" , Mike Kravetz Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On Tue, Nov 12, 2019 at 3:43 PM Jason Gunthorpe wrote: > > On Tue, Nov 12, 2019 at 02:45:51PM -0800, Dan Williams wrote: > > On Tue, Nov 12, 2019 at 2:43 PM John Hubbard wrote: > > > > > > On 11/12/19 12:43 PM, Jason Gunthorpe wrote: > > > ... > > > >> - } > > > >> + ret = get_user_pages_remote(NULL, mm, vaddr, 1, flags | FOLL_LONGTERM, > > > >> + page, vmas, NULL); > > > >> + /* > > > >> + * The lifetime of a vaddr_get_pfn() page pin is > > > >> + * userspace-controlled. In the fs-dax case this could > > > >> + * lead to indefinite stalls in filesystem operations. > > > >> + * Disallow attempts to pin fs-dax pages via this > > > >> + * interface. > > > >> + */ > > > >> + if (ret > 0 && vma_is_fsdax(vmas[0])) { > > > >> + ret = -EOPNOTSUPP; > > > >> + put_page(page[0]); > > > >> } > > > > > > > > AFAIK this chunk is redundant now as it is some hack to emulate > > > > FOLL_LONGTERM? So vmas can be deleted too. > > > > > > Let me first make sure I understand what Dan has in mind for the vma > > > checking, in the other thread... > > > > It's not redundant relative to upstream which does not do anything the > > FOLL_LONGTERM in the gup-slow path... but I have not looked at patches > > 1-7 to see if something there made it redundant. > > Oh, the hunk John had below for get_user_pages_remote() also needs to > call __gup_longterm_locked() when FOLL_LONGTERM is specified, then > that calls check_dax_vmas() which duplicates the vma_is_fsdax() check > above. Oh true, good eye. It is redundant if it does additionally call __gup_longterm_locked(), and it needs to do that otherwises it undoes the CMA migration magic that Aneesh added. > > Certainly no caller of FOLL_LONGTERM should have to do dax specific > VMA checking. Agree, that was my comment about cleaning up the vma_is_fsdax() check to be internal to the gup core. From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dan Williams Subject: Re: [PATCH v3 08/23] vfio, mm: fix get_user_pages_remote() and FOLL_LONGTERM Date: Tue, 12 Nov 2019 16:58:57 -0800 Message-ID: References: <20191112000700.3455038-1-jhubbard@nvidia.com> <20191112000700.3455038-9-jhubbard@nvidia.com> <20191112204338.GE5584@ziepe.ca> <0db36e86-b779-01af-77e7-469af2a2e19c@nvidia.com> <20191112234250.GA19615@ziepe.ca> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Return-path: In-Reply-To: <20191112234250.GA19615@ziepe.ca> Sender: linux-kernel-owner@vger.kernel.org To: Jason Gunthorpe Cc: John Hubbard , Andrew Morton , Al Viro , Alex Williamson , Benjamin Herrenschmidt , =?UTF-8?B?QmrDtnJuIFTDtnBlbA==?= , Christoph Hellwig , Daniel Vetter , Dave Chinner , David Airlie , "David S . Miller" , Ira Weiny , Jan Kara , Jens Axboe , Jonathan Corbet , =?UTF-8?B?SsOpcsO0bWUgR2xpc3Nl?= , Magnus Karlsson , Mauro Carvalho Chehab , Michael Ellerman Mic List-Id: dri-devel@lists.freedesktop.org On Tue, Nov 12, 2019 at 3:43 PM Jason Gunthorpe wrote: > > On Tue, Nov 12, 2019 at 02:45:51PM -0800, Dan Williams wrote: > > On Tue, Nov 12, 2019 at 2:43 PM John Hubbard wrote: > > > > > > On 11/12/19 12:43 PM, Jason Gunthorpe wrote: > > > ... > > > >> - } > > > >> + ret = get_user_pages_remote(NULL, mm, vaddr, 1, flags | FOLL_LONGTERM, > > > >> + page, vmas, NULL); > > > >> + /* > > > >> + * The lifetime of a vaddr_get_pfn() page pin is > > > >> + * userspace-controlled. In the fs-dax case this could > > > >> + * lead to indefinite stalls in filesystem operations. > > > >> + * Disallow attempts to pin fs-dax pages via this > > > >> + * interface. > > > >> + */ > > > >> + if (ret > 0 && vma_is_fsdax(vmas[0])) { > > > >> + ret = -EOPNOTSUPP; > > > >> + put_page(page[0]); > > > >> } > > > > > > > > AFAIK this chunk is redundant now as it is some hack to emulate > > > > FOLL_LONGTERM? So vmas can be deleted too. > > > > > > Let me first make sure I understand what Dan has in mind for the vma > > > checking, in the other thread... > > > > It's not redundant relative to upstream which does not do anything the > > FOLL_LONGTERM in the gup-slow path... but I have not looked at patches > > 1-7 to see if something there made it redundant. > > Oh, the hunk John had below for get_user_pages_remote() also needs to > call __gup_longterm_locked() when FOLL_LONGTERM is specified, then > that calls check_dax_vmas() which duplicates the vma_is_fsdax() check > above. Oh true, good eye. It is redundant if it does additionally call __gup_longterm_locked(), and it needs to do that otherwises it undoes the CMA migration magic that Aneesh added. > > Certainly no caller of FOLL_LONGTERM should have to do dax specific > VMA checking. Agree, that was my comment about cleaning up the vma_is_fsdax() check to be internal to the gup core. 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=-0.8 required=3.0 tests=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 2084DC17441 for ; Wed, 13 Nov 2019 00:59:12 +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 01E7621D7F for ; Wed, 13 Nov 2019 00:59:12 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 01E7621D7F Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 8119A6E045; Wed, 13 Nov 2019 00:59:11 +0000 (UTC) Received: from mail-ot1-x342.google.com (mail-ot1-x342.google.com [IPv6:2607:f8b0:4864:20::342]) by gabe.freedesktop.org (Postfix) with ESMTPS id BBE2C6E045 for ; Wed, 13 Nov 2019 00:59:09 +0000 (UTC) Received: by mail-ot1-x342.google.com with SMTP id m15so127602otq.7 for ; Tue, 12 Nov 2019 16:59:09 -0800 (PST) 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=bbhHvXUlpKSBxAaen2slRAaR7FABAWW5b4ZHt5uDQAs=; b=NkIPaZG1mi0M4CFDl/J/nRsA1RDgYv7qBybMVTVOB3jX+L4+sAJm+03U/w3kOt6lcJ ZD0BjGMV0s3Tgs3+rUv/e7VrYPSKD2SWMCnQZ23FyjrskgM41MNqXk6GYLvhq+NXecEx sNK+P0nRL3i8cvRwNpr7jY9lkGBGbnVJ0dKDIUwg0J6ziamK3n2wzPGBp0jmJ9HSv4k9 8z707dYCFfQYyCdGflHN0et619PAxbsszAaI/pGHJpdHjAgUN/FzB8s5TcqoXlIAhZcK C1Zq+e8kn0gtF9rtNEbbJ1X84LZLYtUntDpfmno+oADuwHlElrc/fnmWgIVyq8uTa/hL CW2A== X-Gm-Message-State: APjAAAVC7WJKcvkPGEbiH4XTnbZg/hz9CS2DBaqOHBMdiB3A2QMsnBGX X4YDqp6jk6HEuE9B1Ww4hn60CV30qrWHf5A55r3qpQ== X-Google-Smtp-Source: APXvYqwE5wMeaGSIvNyY2BTy28AxuQMGsjlQOMQJ/g9Nuz73c9JXx/mbsafhYfzhqVldWgO1VAvXOO9/vT+g3CHkLek= X-Received: by 2002:a05:6830:1b70:: with SMTP id d16mr300372ote.71.1573606748988; Tue, 12 Nov 2019 16:59:08 -0800 (PST) MIME-Version: 1.0 References: <20191112000700.3455038-1-jhubbard@nvidia.com> <20191112000700.3455038-9-jhubbard@nvidia.com> <20191112204338.GE5584@ziepe.ca> <0db36e86-b779-01af-77e7-469af2a2e19c@nvidia.com> <20191112234250.GA19615@ziepe.ca> In-Reply-To: <20191112234250.GA19615@ziepe.ca> From: Dan Williams Date: Tue, 12 Nov 2019 16:58:57 -0800 Message-ID: Subject: Re: [PATCH v3 08/23] vfio, mm: fix get_user_pages_remote() and FOLL_LONGTERM To: Jason Gunthorpe X-Mailman-Original-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=intel-com.20150623.gappssmtp.com; s=20150623; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=bbhHvXUlpKSBxAaen2slRAaR7FABAWW5b4ZHt5uDQAs=; b=aNNgsrA5EIFA9nVSCXy/uyenu1ifAR2ZxMR/sDW6HqK6vSTYpxIpmBrjP/vDjDaVnk l4xh/AHHGyooUHFp1c42LTwLTpwdgtUaJfWvN3Y7CFSVzmwzvxLUaHQBl+Ibev8TBoid 2FUFgDLM8vD2vOwzS+IEshtyE4Y+b3ieXpqqo3Mxdly/m4ak6FnwfnCLEy5DGwsI7qq9 7rFre8WIcpfUZvKl+y7wQa6yOvynR61ZdKROoMobKwRLP3lkc2bkhgPK6DIYIEcGXZ4p WUPwy1pR33Kp+/7N+4r5VmPuWnlSLsuN14iR6BROP5kh/8NTzRoeUzJllo7I56/tNtvu ttpQ== X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Michal Hocko , Jan Kara , KVM list , Linux Doc Mailing List , David Airlie , Dave Chinner , Maling list - DRI developers , LKML , Linux MM , Paul Mackerras , linux-kselftest@vger.kernel.org, Ira Weiny , Jonathan Corbet , linux-rdma , Michael Ellerman , Christoph Hellwig , Vlastimil Babka , =?UTF-8?B?QmrDtnJuIFTDtnBlbA==?= , "Linux-media@vger.kernel.org" , Shuah Khan , John Hubbard , linux-block@vger.kernel.org, =?UTF-8?B?SsOpcsO0bWUgR2xpc3Nl?= , Al Viro , Mauro Carvalho Chehab , bpf@vger.kernel.org, Magnus Karlsson , Jens Axboe , Netdev , Alex Williamson , linux-fsdevel , Andrew Morton , linuxppc-dev , "David S . Miller" , Mike Kravetz Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Message-ID: <20191113005857.X1yMBAk1CzBxmNZq8zNeUTOuKvsbcbCmNU71XJyHsl4@z> T24gVHVlLCBOb3YgMTIsIDIwMTkgYXQgMzo0MyBQTSBKYXNvbiBHdW50aG9ycGUgPGpnZ0B6aWVw ZS5jYT4gd3JvdGU6Cj4KPiBPbiBUdWUsIE5vdiAxMiwgMjAxOSBhdCAwMjo0NTo1MVBNIC0wODAw LCBEYW4gV2lsbGlhbXMgd3JvdGU6Cj4gPiBPbiBUdWUsIE5vdiAxMiwgMjAxOSBhdCAyOjQzIFBN IEpvaG4gSHViYmFyZCA8amh1YmJhcmRAbnZpZGlhLmNvbT4gd3JvdGU6Cj4gPiA+Cj4gPiA+IE9u IDExLzEyLzE5IDEyOjQzIFBNLCBKYXNvbiBHdW50aG9ycGUgd3JvdGU6Cj4gPiA+IC4uLgo+ID4g PiA+PiAtICAgICAgICAgICAgfQo+ID4gPiA+PiArICAgIHJldCA9IGdldF91c2VyX3BhZ2VzX3Jl bW90ZShOVUxMLCBtbSwgdmFkZHIsIDEsIGZsYWdzIHwgRk9MTF9MT05HVEVSTSwKPiA+ID4gPj4g KyAgICAgICAgICAgICAgICAgICAgICAgICAgICAgICAgcGFnZSwgdm1hcywgTlVMTCk7Cj4gPiA+ ID4+ICsgICAgLyoKPiA+ID4gPj4gKyAgICAgKiBUaGUgbGlmZXRpbWUgb2YgYSB2YWRkcl9nZXRf cGZuKCkgcGFnZSBwaW4gaXMKPiA+ID4gPj4gKyAgICAgKiB1c2Vyc3BhY2UtY29udHJvbGxlZC4g SW4gdGhlIGZzLWRheCBjYXNlIHRoaXMgY291bGQKPiA+ID4gPj4gKyAgICAgKiBsZWFkIHRvIGlu ZGVmaW5pdGUgc3RhbGxzIGluIGZpbGVzeXN0ZW0gb3BlcmF0aW9ucy4KPiA+ID4gPj4gKyAgICAg KiBEaXNhbGxvdyBhdHRlbXB0cyB0byBwaW4gZnMtZGF4IHBhZ2VzIHZpYSB0aGlzCj4gPiA+ID4+ ICsgICAgICogaW50ZXJmYWNlLgo+ID4gPiA+PiArICAgICAqLwo+ID4gPiA+PiArICAgIGlmIChy ZXQgPiAwICYmIHZtYV9pc19mc2RheCh2bWFzWzBdKSkgewo+ID4gPiA+PiArICAgICAgICAgICAg cmV0ID0gLUVPUE5PVFNVUFA7Cj4gPiA+ID4+ICsgICAgICAgICAgICBwdXRfcGFnZShwYWdlWzBd KTsKPiA+ID4gPj4gICAgICB9Cj4gPiA+ID4KPiA+ID4gPiBBRkFJSyB0aGlzIGNodW5rIGlzIHJl ZHVuZGFudCBub3cgYXMgaXQgaXMgc29tZSBoYWNrIHRvIGVtdWxhdGUKPiA+ID4gPiBGT0xMX0xP TkdURVJNPyBTbyB2bWFzIGNhbiBiZSBkZWxldGVkIHRvby4KPiA+ID4KPiA+ID4gTGV0IG1lIGZp cnN0IG1ha2Ugc3VyZSBJIHVuZGVyc3RhbmQgd2hhdCBEYW4gaGFzIGluIG1pbmQgZm9yIHRoZSB2 bWEKPiA+ID4gY2hlY2tpbmcsIGluIHRoZSBvdGhlciB0aHJlYWQuLi4KPiA+Cj4gPiBJdCdzIG5v dCByZWR1bmRhbnQgcmVsYXRpdmUgdG8gdXBzdHJlYW0gd2hpY2ggZG9lcyBub3QgZG8gYW55dGhp bmcgdGhlCj4gPiBGT0xMX0xPTkdURVJNIGluIHRoZSBndXAtc2xvdyBwYXRoLi4uIGJ1dCBJIGhh dmUgbm90IGxvb2tlZCBhdCBwYXRjaGVzCj4gPiAxLTcgdG8gc2VlIGlmIHNvbWV0aGluZyB0aGVy ZSBtYWRlIGl0IHJlZHVuZGFudC4KPgo+IE9oLCB0aGUgaHVuayBKb2huIGhhZCBiZWxvdyBmb3Ig Z2V0X3VzZXJfcGFnZXNfcmVtb3RlKCkgYWxzbyBuZWVkcyB0bwo+IGNhbGwgX19ndXBfbG9uZ3Rl cm1fbG9ja2VkKCkgd2hlbiBGT0xMX0xPTkdURVJNIGlzIHNwZWNpZmllZCwgdGhlbgo+IHRoYXQg Y2FsbHMgY2hlY2tfZGF4X3ZtYXMoKSB3aGljaCBkdXBsaWNhdGVzIHRoZSB2bWFfaXNfZnNkYXgo KSBjaGVjawo+IGFib3ZlLgoKT2ggdHJ1ZSwgZ29vZCBleWUuIEl0IGlzIHJlZHVuZGFudCBpZiBp dCBkb2VzIGFkZGl0aW9uYWxseSBjYWxsCl9fZ3VwX2xvbmd0ZXJtX2xvY2tlZCgpLCBhbmQgaXQg bmVlZHMgdG8gZG8gdGhhdCBvdGhlcndpc2VzIGl0IHVuZG9lcwp0aGUgQ01BIG1pZ3JhdGlvbiBt YWdpYyB0aGF0IEFuZWVzaCBhZGRlZC4KCj4KPiBDZXJ0YWlubHkgbm8gY2FsbGVyIG9mIEZPTExf TE9OR1RFUk0gc2hvdWxkIGhhdmUgdG8gZG8gZGF4IHNwZWNpZmljCj4gVk1BIGNoZWNraW5nLgoK QWdyZWUsIHRoYXQgd2FzIG15IGNvbW1lbnQgYWJvdXQgY2xlYW5pbmcgdXAgdGhlIHZtYV9pc19m c2RheCgpIGNoZWNrCnRvIGJlIGludGVybmFsIHRvIHRoZSBndXAgY29yZS4KX19fX19fX19fX19f X19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX18KZHJpLWRldmVsIG1haWxpbmcgbGlz dApkcmktZGV2ZWxAbGlzdHMuZnJlZWRlc2t0b3Aub3JnCmh0dHBzOi8vbGlzdHMuZnJlZWRlc2t0 b3Aub3JnL21haWxtYW4vbGlzdGluZm8vZHJpLWRldmVs