From mboxrd@z Thu Jan 1 00:00:00 1970 From: Qian Cai Date: Tue, 28 Jan 2020 05:48:30 +0000 Subject: Re: [PATCH V12] mm/debug: Add tests validating architecture page table helpers Message-Id: List-Id: References: <012158b7-a40e-050f-cd1b-d6ce7faf042f@arm.com> In-Reply-To: <012158b7-a40e-050f-cd1b-d6ce7faf042f@arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit To: Anshuman Khandual Cc: Mark Rutland , linux-ia64@vger.kernel.org, linux-sh@vger.kernel.org, Peter Zijlstra , James Hogan , Tetsuo Handa , Heiko Carstens , Michal Hocko , Linux-MM , Dave Hansen , Paul Mackerras , sparclinux@vger.kernel.org, Thomas Gleixner , linux-s390@vger.kernel.org, Michael Ellerman , x86@kernel.org, Russell King - ARM Linux , Matthew Wilcox , Steven Price , Jason Gunthorpe , Gerald Schaefer , linux-snps-arc@lists.infradead.org, linux-arm-kernel@lists.infradead.org, Ingo Molnar , Kees Cook , Masahiro Yamada , Mark Brown , "Kirill A . Shutemov" , Dan Williams , Vlastimil Babka , Christophe Leroy , Sri Krishna chowdary , Ard Biesheuvel , Greg Kroah-Hartman , linux-mips@vger.kernel.org, Ralf Baechle , linux-kernel@vger.kernel.org, Paul Burton , Mike Rapoport , Vineet Gupta , Martin Schwidefsky , Andrew Morton , linuxppc-dev@lists.ozlabs.org, "David S. Miller" > On Jan 27, 2020, at 11:58 PM, Anshuman Khandual wrote: > > As I had mentioned before, the test attempts to formalize page table helper semantics > as expected from generic MM code paths and intend to catch deviations when enabled on > a given platform. How else should we test semantics errors otherwise ? There are past > examples of usefulness for this procedure on arm64 and on s390. I am wondering how > else to prove the usefulness of a debug feature if these references are not enough. Not saying it will not be useful. As you mentioned it actually found a bug or two in the past. The problem is that there is always a cost to maintain something like this, and nobody knew how things could be broken even for the isolated code you mentioned in the future given how complicated the kernel code base is. I am not so positive that many developers would enable this debug feature and use it on a regular basis from the information you gave so far. On the other hand, it might just be good at maintaining this thing out of tree by yourself anyway, because if there isn’t going to be used by many developers, few people is going to contribute to this and even noticed when it is broken. What’s the point of getting this merged apart from being getting some meaningless credits? 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, DKIM_VALID_AU,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 5666CC35246 for ; Tue, 28 Jan 2020 05:48:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2AEF424682 for ; Tue, 28 Jan 2020 05:48:34 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lca.pw header.i=@lca.pw header.b="Hma1sjKp" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725867AbgA1Fsd (ORCPT ); Tue, 28 Jan 2020 00:48:33 -0500 Received: from mail-qk1-f196.google.com ([209.85.222.196]:46096 "EHLO mail-qk1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725799AbgA1Fsc (ORCPT ); Tue, 28 Jan 2020 00:48:32 -0500 Received: by mail-qk1-f196.google.com with SMTP id g195so12192449qke.13 for ; Mon, 27 Jan 2020 21:48:32 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=lca.pw; s=google; h=content-transfer-encoding:from:mime-version:subject:date:message-id :references:cc:in-reply-to:to; bh=LCR4yoPyKXUQ+V6Rzx8Vr1pGJBzG7ybCO5xmGhWVO2E=; b=Hma1sjKpCAmCNDeQeafPYa2ae6jBDESB1PCm6wfy4m1d7M9+BWh8FVkywYWY7ykCiy SzQx25lgeC+4duHJWx6KqUIh8QXTw8di5MeaGwQuHHn89Nhc7uYjdWvvsMbKeA7vFD83 eZ0ttxqv+O0UBv0Q1ELfjNP83to7CnSAWkh7s2C27oDB+u7jHIZRBxLZHGidOdsQf1JK mEEo4/yiVKjxGyBlmRHpRnDqvkuHhNTxRoPqy1Zumzpfc60DAz3G+S+hPw5+FUChoT/q bS0YqS6g/Diq0QYdhlCFXqUUyepH5ufSRHLX0WMtxLjOyn6wC8W9mPq32swU9Z657Mb6 aYdQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:content-transfer-encoding:from:mime-version :subject:date:message-id:references:cc:in-reply-to:to; bh=LCR4yoPyKXUQ+V6Rzx8Vr1pGJBzG7ybCO5xmGhWVO2E=; b=oQz+qiO82Y6KdiB0D2WgL6TLKRm4j0bwssukByvulJf4VCKRzJ1eLk5Ft55GssEj9n yM0HKNSG+LgC2WvHYRVxALXXEH5wioj9rP6NDkPfpOXAwNmgftfQzr+WURUes1jwCCVg qgV3mIS890CQwA44D9ZCHjyftOH1lnp8ZdzA2vv2/1AHiQyXIjAWcT5qn26cD9SWYL4x sVzZAXhEnHkTYFm2hzlw5yar6ztSSsNxVwS5fbg6sAGYN4H6aS8iscQsyj5xiPmNt8aG ygOYi61HTW5RUvqZ1L2UPaLSG7I/QuNWxmWRWrFRp9RUPblZRpwEsnINg3EUsvlGtEN/ RwLA== X-Gm-Message-State: APjAAAVUHd25BgoLx9oTqsRQNW1PbILarfOx3ZZVavzia60lwhgcq/bV zqAq9I3hkAicTjWRayVHxT8OoA== X-Google-Smtp-Source: APXvYqwn3oHOOTfkm4bMswvjR/8+st1VKZNpzuQd0q1CmHzfURBt8o3+PL4pjZF1Mk5vBV26vMgvyQ== X-Received: by 2002:ae9:edc8:: with SMTP id c191mr20758894qkg.227.1580190511462; Mon, 27 Jan 2020 21:48:31 -0800 (PST) Received: from [192.168.1.183] (pool-71-184-117-43.bstnma.fios.verizon.net. [71.184.117.43]) by smtp.gmail.com with ESMTPSA id 8sm11519536qkm.92.2020.01.27.21.48.30 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 27 Jan 2020 21:48:30 -0800 (PST) Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable From: Qian Cai Mime-Version: 1.0 (1.0) Subject: Re: [PATCH V12] mm/debug: Add tests validating architecture page table helpers Date: Tue, 28 Jan 2020 00:48:30 -0500 Message-Id: References: <012158b7-a40e-050f-cd1b-d6ce7faf042f@arm.com> Cc: Linux-MM , Andrew Morton , Vlastimil Babka , Greg Kroah-Hartman , Thomas Gleixner , Mike Rapoport , Jason Gunthorpe , Dan Williams , Peter Zijlstra , Michal Hocko , Mark Rutland , Mark Brown , Steven Price , Ard Biesheuvel , Masahiro Yamada , Kees Cook , Tetsuo Handa , Matthew Wilcox , Sri Krishna chowdary , Dave Hansen , Russell King - ARM Linux , Michael Ellerman , Paul Mackerras , Martin Schwidefsky , Heiko Carstens , "David S. Miller" , Vineet Gupta , James Hogan , Paul Burton , Ralf Baechle , "Kirill A . Shutemov" , Gerald Schaefer , Christophe Leroy , Ingo Molnar , linux-snps-arc@lists.infradead.org, linux-mips@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-ia64@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org, sparclinux@vger.kernel.org, x86@kernel.org, linux-kernel@vger.kernel.org In-Reply-To: <012158b7-a40e-050f-cd1b-d6ce7faf042f@arm.com> To: Anshuman Khandual X-Mailer: iPhone Mail (17C54) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > On Jan 27, 2020, at 11:58 PM, Anshuman Khandual wrote: >=20 > As I had mentioned before, the test attempts to formalize page table helpe= r semantics > as expected from generic MM code paths and intend to catch deviations when= enabled on > a given platform. How else should we test semantics errors otherwise ? The= re are past > examples of usefulness for this procedure on arm64 and on s390. I am wonde= ring how > else to prove the usefulness of a debug feature if these references are no= t enough. Not saying it will not be useful. As you mentioned it actually found a bug o= r two in the past. The problem is that there is always a cost to maintain so= mething like this, and nobody knew how things could be broken even for the i= solated code you mentioned in the future given how complicated the kernel co= de base is. I am not so positive that many developers would enable this debu= g feature and use it on a regular basis from the information you gave so far= .=20 On the other hand, it might just be good at maintaining this thing out of tr= ee by yourself anyway, because if there isn=E2=80=99t going to be used by ma= ny developers, few people is going to contribute to this and even noticed wh= en it is broken. What=E2=80=99s the point of getting this merged apart from b= eing getting some meaningless credits?= 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=-0.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, 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 04BCFC33CB3 for ; Tue, 28 Jan 2020 05:50:42 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (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 9D3F32467B for ; Tue, 28 Jan 2020 05:50:41 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=lca.pw header.i=@lca.pw header.b="Hma1sjKp" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9D3F32467B Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=lca.pw Authentication-Results: mail.kernel.org; spf=tempfail smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 486G1T6y9zzDqBW for ; Tue, 28 Jan 2020 16:50:37 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=lca.pw (client-ip=2607:f8b0:4864:20::744; helo=mail-qk1-x744.google.com; envelope-from=cai@lca.pw; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=lca.pw Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=lca.pw header.i=@lca.pw header.a=rsa-sha256 header.s=google header.b=Hma1sjKp; dkim-atps=neutral Received: from mail-qk1-x744.google.com (mail-qk1-x744.google.com [IPv6:2607:f8b0:4864:20::744]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 486Fz83lh0zDqBL for ; Tue, 28 Jan 2020 16:48:35 +1100 (AEDT) Received: by mail-qk1-x744.google.com with SMTP id j20so12211256qka.10 for ; Mon, 27 Jan 2020 21:48:34 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=lca.pw; s=google; h=content-transfer-encoding:from:mime-version:subject:date:message-id :references:cc:in-reply-to:to; bh=LCR4yoPyKXUQ+V6Rzx8Vr1pGJBzG7ybCO5xmGhWVO2E=; b=Hma1sjKpCAmCNDeQeafPYa2ae6jBDESB1PCm6wfy4m1d7M9+BWh8FVkywYWY7ykCiy SzQx25lgeC+4duHJWx6KqUIh8QXTw8di5MeaGwQuHHn89Nhc7uYjdWvvsMbKeA7vFD83 eZ0ttxqv+O0UBv0Q1ELfjNP83to7CnSAWkh7s2C27oDB+u7jHIZRBxLZHGidOdsQf1JK mEEo4/yiVKjxGyBlmRHpRnDqvkuHhNTxRoPqy1Zumzpfc60DAz3G+S+hPw5+FUChoT/q bS0YqS6g/Diq0QYdhlCFXqUUyepH5ufSRHLX0WMtxLjOyn6wC8W9mPq32swU9Z657Mb6 aYdQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:content-transfer-encoding:from:mime-version :subject:date:message-id:references:cc:in-reply-to:to; bh=LCR4yoPyKXUQ+V6Rzx8Vr1pGJBzG7ybCO5xmGhWVO2E=; b=Ir1VGH8qEj8muFPOu+eqPR3flpfy8CHsw5U164OUIlxDW4N5NlYUiz9gChpRMDfQab xjrTfDzYMCzY1Bv6BE7fRyokEVQxVaqwMnCLd5BNn5WznPnt18SXW7WYjLv4WjfWtPgX mnZEXe9Nlk/g3OTqOgmBjyGoNI/NYUq7aTmkHK7DKrb0/o310G8y9g/PHgr0YbC4n3SH krAnZIBHiT/lOs++KbmKSLR7eQ6iXscaLSksvzNJFuk8/GZMcXD5hdtApjtNyiooZR2/ O0BssJJLOImSSOUv6xwdr5xwhsxp0QmYOYPtwawWPoGT9Dhg9Fq9GassmGt04TaGjabG lyUQ== X-Gm-Message-State: APjAAAWVQ1JRkeNwRe9JJiFAc8ohJEkhrXYafT4jYUYWIJoO4L5oY3io nqUppBhYTbZKrP4OBVGq2+CrZg== X-Google-Smtp-Source: APXvYqwn3oHOOTfkm4bMswvjR/8+st1VKZNpzuQd0q1CmHzfURBt8o3+PL4pjZF1Mk5vBV26vMgvyQ== X-Received: by 2002:ae9:edc8:: with SMTP id c191mr20758894qkg.227.1580190511462; Mon, 27 Jan 2020 21:48:31 -0800 (PST) Received: from [192.168.1.183] (pool-71-184-117-43.bstnma.fios.verizon.net. [71.184.117.43]) by smtp.gmail.com with ESMTPSA id 8sm11519536qkm.92.2020.01.27.21.48.30 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 27 Jan 2020 21:48:30 -0800 (PST) Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable From: Qian Cai Mime-Version: 1.0 (1.0) Subject: Re: [PATCH V12] mm/debug: Add tests validating architecture page table helpers Date: Tue, 28 Jan 2020 00:48:30 -0500 Message-Id: References: <012158b7-a40e-050f-cd1b-d6ce7faf042f@arm.com> In-Reply-To: <012158b7-a40e-050f-cd1b-d6ce7faf042f@arm.com> To: Anshuman Khandual X-Mailer: iPhone Mail (17C54) 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: Mark Rutland , linux-ia64@vger.kernel.org, linux-sh@vger.kernel.org, Peter Zijlstra , James Hogan , Tetsuo Handa , Heiko Carstens , Michal Hocko , Linux-MM , Dave Hansen , Paul Mackerras , sparclinux@vger.kernel.org, Thomas Gleixner , linux-s390@vger.kernel.org, x86@kernel.org, Russell King - ARM Linux , Matthew Wilcox , Steven Price , Jason Gunthorpe , Gerald Schaefer , linux-snps-arc@lists.infradead.org, linux-arm-kernel@lists.infradead.org, Ingo Molnar , Kees Cook , Masahiro Yamada , Mark Brown , "Kirill A . Shutemov" , Dan Williams , Vlastimil Babka , Sri Krishna chowdary , Ard Biesheuvel , Greg Kroah-Hartman , linux-mips@vger.kernel.org, Ralf Baechle , linux-kernel@vger.kernel.org, Paul Burton , Mike Rapoport , Vineet Gupta , Martin Schwidefsky , Andrew Morton , linuxppc-dev@lists.ozlabs.org, "David S. Miller" Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" > On Jan 27, 2020, at 11:58 PM, Anshuman Khandual wrote: >=20 > As I had mentioned before, the test attempts to formalize page table helpe= r semantics > as expected from generic MM code paths and intend to catch deviations when= enabled on > a given platform. How else should we test semantics errors otherwise ? The= re are past > examples of usefulness for this procedure on arm64 and on s390. I am wonde= ring how > else to prove the usefulness of a debug feature if these references are no= t enough. Not saying it will not be useful. As you mentioned it actually found a bug o= r two in the past. The problem is that there is always a cost to maintain so= mething like this, and nobody knew how things could be broken even for the i= solated code you mentioned in the future given how complicated the kernel co= de base is. I am not so positive that many developers would enable this debu= g feature and use it on a regular basis from the information you gave so far= .=20 On the other hand, it might just be good at maintaining this thing out of tr= ee by yourself anyway, because if there isn=E2=80=99t going to be used by ma= ny developers, few people is going to contribute to this and even noticed wh= en it is broken. 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[71.184.117.43]) by smtp.gmail.com with ESMTPSA id 8sm11519536qkm.92.2020.01.27.21.48.30 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 27 Jan 2020 21:48:30 -0800 (PST) From: Qian Cai Mime-Version: 1.0 (1.0) Subject: Re: [PATCH V12] mm/debug: Add tests validating architecture page table helpers Date: Tue, 28 Jan 2020 00:48:30 -0500 Message-Id: References: <012158b7-a40e-050f-cd1b-d6ce7faf042f@arm.com> In-Reply-To: <012158b7-a40e-050f-cd1b-d6ce7faf042f@arm.com> To: Anshuman Khandual X-Mailer: iPhone Mail (17C54) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200127_214833_204372_A24A5C6F X-CRM114-Status: GOOD ( 14.48 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , linux-ia64@vger.kernel.org, linux-sh@vger.kernel.org, Peter Zijlstra , James Hogan , Tetsuo Handa , Heiko Carstens , Michal Hocko , Linux-MM , Dave Hansen , Paul Mackerras , sparclinux@vger.kernel.org, Thomas Gleixner , linux-s390@vger.kernel.org, Michael Ellerman , x86@kernel.org, Russell King - ARM Linux , Matthew Wilcox , Steven Price , Jason Gunthorpe , Gerald Schaefer , linux-snps-arc@lists.infradead.org, linux-arm-kernel@lists.infradead.org, Ingo Molnar , Kees Cook , Masahiro Yamada , Mark Brown , "Kirill A . 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Miller" Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org Cgo+IE9uIEphbiAyNywgMjAyMCwgYXQgMTE6NTggUE0sIEFuc2h1bWFuIEtoYW5kdWFsIDxBbnNo dW1hbi5LaGFuZHVhbEBhcm0uY29tPiB3cm90ZToKPiAKPiBBcyBJIGhhZCBtZW50aW9uZWQgYmVm b3JlLCB0aGUgdGVzdCBhdHRlbXB0cyB0byBmb3JtYWxpemUgcGFnZSB0YWJsZSBoZWxwZXIgc2Vt YW50aWNzCj4gYXMgZXhwZWN0ZWQgZnJvbSBnZW5lcmljIE1NIGNvZGUgcGF0aHMgYW5kIGludGVu ZCB0byBjYXRjaCBkZXZpYXRpb25zIHdoZW4gZW5hYmxlZCBvbgo+IGEgZ2l2ZW4gcGxhdGZvcm0u IEhvdyBlbHNlIHNob3VsZCB3ZSB0ZXN0IHNlbWFudGljcyBlcnJvcnMgb3RoZXJ3aXNlID8gVGhl cmUgYXJlIHBhc3QKPiBleGFtcGxlcyBvZiB1c2VmdWxuZXNzIGZvciB0aGlzIHByb2NlZHVyZSBv biBhcm02NCBhbmQgb24gczM5MC4gSSBhbSB3b25kZXJpbmcgaG93Cj4gZWxzZSB0byBwcm92ZSB0 aGUgdXNlZnVsbmVzcyBvZiBhIGRlYnVnIGZlYXR1cmUgaWYgdGhlc2UgcmVmZXJlbmNlcyBhcmUg bm90IGVub3VnaC4KCk5vdCBzYXlpbmcgaXQgd2lsbCBub3QgYmUgdXNlZnVsLiBBcyB5b3UgbWVu dGlvbmVkIGl0IGFjdHVhbGx5IGZvdW5kIGEgYnVnIG9yIHR3byBpbiB0aGUgcGFzdC4gVGhlIHBy b2JsZW0gaXMgdGhhdCB0aGVyZSBpcyBhbHdheXMgYSBjb3N0IHRvIG1haW50YWluIHNvbWV0aGlu ZyBsaWtlIHRoaXMsIGFuZCBub2JvZHkga25ldyBob3cgdGhpbmdzIGNvdWxkIGJlIGJyb2tlbiBl dmVuIGZvciB0aGUgaXNvbGF0ZWQgY29kZSB5b3UgbWVudGlvbmVkIGluIHRoZSBmdXR1cmUgZ2l2 ZW4gaG93IGNvbXBsaWNhdGVkIHRoZSBrZXJuZWwgY29kZSBiYXNlIGlzLiBJIGFtIG5vdCBzbyBw b3NpdGl2ZSB0aGF0IG1hbnkgZGV2ZWxvcGVycyB3b3VsZCBlbmFibGUgdGhpcyBkZWJ1ZyBmZWF0 dXJlIGFuZCB1c2UgaXQgb24gYSByZWd1bGFyIGJhc2lzIGZyb20gdGhlIGluZm9ybWF0aW9uIHlv dSBnYXZlIHNvIGZhci4gCgpPbiB0aGUgb3RoZXIgaGFuZCwgaXQgbWlnaHQganVzdCBiZSBnb29k IGF0IG1haW50YWluaW5nIHRoaXMgdGhpbmcgb3V0IG9mIHRyZWUgYnkgeW91cnNlbGYgYW55d2F5 LCBiZWNhdXNlIGlmIHRoZXJlIGlzbuKAmXQgZ29pbmcgdG8gYmUgdXNlZCBieSBtYW55IGRldmVs b3BlcnMsIGZldyBwZW9wbGUgaXMgZ29pbmcgdG8gY29udHJpYnV0ZSB0byB0aGlzIGFuZCBldmVu IG5vdGljZWQgd2hlbiBpdCBpcyBicm9rZW4uIFdoYXTigJlzIHRoZSBwb2ludCBvZiBnZXR0aW5n IHRoaXMgbWVyZ2VkIGFwYXJ0IGZyb20gYmVpbmcgZ2V0dGluZyBzb21lIG1lYW5pbmdsZXNzIGNy ZWRpdHM/Cl9fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fCmxp bnV4LWFybS1rZXJuZWwgbWFpbGluZyBsaXN0CmxpbnV4LWFybS1rZXJuZWxAbGlzdHMuaW5mcmFk ZWFkLm9yZwpodHRwOi8vbGlzdHMuaW5mcmFkZWFkLm9yZy9tYWlsbWFuL2xpc3RpbmZvL2xpbnV4 LWFybS1rZXJuZWwK