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 4DBABC433FE for ; Mon, 16 May 2022 16:18:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1343520AbiEPQSN (ORCPT ); Mon, 16 May 2022 12:18:13 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:32818 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232773AbiEPQSK (ORCPT ); Mon, 16 May 2022 12:18:10 -0400 Received: from mga05.intel.com (mga05.intel.com [192.55.52.43]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5A67638184; Mon, 16 May 2022 09:18:09 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1652717889; x=1684253889; h=from:to:cc:subject:date:message-id:references: in-reply-to:content-transfer-encoding:mime-version; bh=+l+W5AAGJYF9POu96DFeN42Yp1wDBbNs2cT6ebzm1Q4=; b=gE3JndFmb3MVc+y8k0MigjEzVzCqGvTnKuZFhE4DjcCYaU4+iqRdm1YK P0DDqVHBLoq7VKipOO0hdvZYV9pVTZG1CN68yC4Fs1ioVILwIZ3Q2SrMn sSdjpODOS6uWQjCqGoSIJu1pba5omJEmL1FQURGDTGfZUlS1TXhoGF22j h0UKzl3D3f9Sw7CU71YSSLPCDk1YAxt17+ONuVJQaBsvQLE0imNdebkVK Q0O82ERRbpa9leBWTCKvYYiIIzee1lVvNZNkYwosdrYyHDA3KJBcn4HGB Wc7wLsviGum79vhrgzLiyhyPVYTFfrQj6/p9kQjA+0ss/R8t28ygKVZCy A==; X-IronPort-AV: E=McAfee;i="6400,9594,10349"; a="357293807" X-IronPort-AV: E=Sophos;i="5.91,230,1647327600"; d="scan'208";a="357293807" Received: from orsmga008.jf.intel.com ([10.7.209.65]) by fmsmga105.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 16 May 2022 09:18:08 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.91,230,1647327600"; d="scan'208";a="596591798" Received: from fmsmsx605.amr.corp.intel.com ([10.18.126.85]) by orsmga008.jf.intel.com with ESMTP; 16 May 2022 09:18:05 -0700 Received: from fmsmsx612.amr.corp.intel.com (10.18.126.92) by fmsmsx605.amr.corp.intel.com (10.18.126.85) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.27; Mon, 16 May 2022 09:18:05 -0700 Received: from fmsmsx610.amr.corp.intel.com (10.18.126.90) by fmsmsx612.amr.corp.intel.com (10.18.126.92) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.27; Mon, 16 May 2022 09:18:04 -0700 Received: from fmsmsx610.amr.corp.intel.com ([10.18.126.90]) by fmsmsx610.amr.corp.intel.com ([10.18.126.90]) with mapi id 15.01.2308.027; Mon, 16 May 2022 09:18:04 -0700 From: "Luck, Tony" To: "Guilherme G. Piccoli" , Petr Mladek , Dinh Nguyen CC: "akpm@linux-foundation.org" , "bhe@redhat.com" , "kexec@lists.infradead.org" , "linux-kernel@vger.kernel.org" , "bcm-kernel-feedback-list@broadcom.com" , "linuxppc-dev@lists.ozlabs.org" , "linux-alpha@vger.kernel.org" , "linux-edac@vger.kernel.org" , "linux-hyperv@vger.kernel.org" , "linux-leds@vger.kernel.org" , "linux-mips@vger.kernel.org" , "linux-parisc@vger.kernel.org" , "linux-pm@vger.kernel.org" , "linux-remoteproc@vger.kernel.org" , "linux-s390@vger.kernel.org" , "linux-tegra@vger.kernel.org" , "linux-um@lists.infradead.org" , "linux-xtensa@linux-xtensa.org" , "netdev@vger.kernel.org" , "openipmi-developer@lists.sourceforge.net" , "rcu@vger.kernel.org" , "sparclinux@vger.kernel.org" , "xen-devel@lists.xenproject.org" , "x86@kernel.org" , "kernel-dev@igalia.com" , "kernel@gpiccoli.net" , "halves@canonical.com" , "fabiomirmar@gmail.com" , "alejandro.j.jimenez@oracle.com" , "andriy.shevchenko@linux.intel.com" , "arnd@arndb.de" , "bp@alien8.de" , "corbet@lwn.net" , "d.hatayama@jp.fujitsu.com" , "dave.hansen@linux.intel.com" , "dyoung@redhat.com" , "Tang, Feng" , "gregkh@linuxfoundation.org" , "mikelley@microsoft.com" , "hidehiro.kawai.ez@hitachi.com" , "jgross@suse.com" , "john.ogness@linutronix.de" , "keescook@chromium.org" , "luto@kernel.org" , "mhiramat@kernel.org" , "mingo@redhat.com" , "paulmck@kernel.org" , "peterz@infradead.org" , "rostedt@goodmis.org" , "senozhatsky@chromium.org" , "stern@rowland.harvard.edu" , "tglx@linutronix.de" , "vgoyal@redhat.com" , "vkuznets@redhat.com" , "will@kernel.org" , Alex Elder , Alexander Gordeev , Anton Ivanov , Benjamin Herrenschmidt , Bjorn Andersson , Boris Ostrovsky , Chris Zankel , Christian Borntraeger , "Corey Minyard" , Dexuan Cui , "H. Peter Anvin" , Haiyang Zhang , "Heiko Carstens" , Helge Deller , Ivan Kokshaysky , "James E.J. Bottomley" , James Morse , Johannes Berg , "K. Y. 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d="scan'208";a="596591798" Received: from fmsmsx605.amr.corp.intel.com ([10.18.126.85]) by orsmga008.jf.intel.com with ESMTP; 16 May 2022 09:18:05 -0700 Received: from fmsmsx612.amr.corp.intel.com (10.18.126.92) by fmsmsx605.amr.corp.intel.com (10.18.126.85) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.27; Mon, 16 May 2022 09:18:05 -0700 Received: from fmsmsx610.amr.corp.intel.com (10.18.126.90) by fmsmsx612.amr.corp.intel.com (10.18.126.92) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.27; Mon, 16 May 2022 09:18:04 -0700 Received: from fmsmsx610.amr.corp.intel.com ([10.18.126.90]) by fmsmsx610.amr.corp.intel.com ([10.18.126.90]) with mapi id 15.01.2308.027; Mon, 16 May 2022 09:18:04 -0700 From: "Luck, Tony" To: "Guilherme G. Piccoli" , Petr Mladek , Dinh Nguyen Subject: RE: [PATCH 21/30] panic: Introduce the panic pre-reboot notifier list Thread-Topic: [PATCH 21/30] panic: Introduce the panic pre-reboot notifier list Thread-Index: AQHYWooLnXaT7guJw0OCpuGv/IkEoK0iJCSAgAAZuAD//40QkA== Date: Mon, 16 May 2022 16:18:04 +0000 Message-ID: References: <20220427224924.592546-1-gpiccoli@igalia.com> <20220427224924.592546-22-gpiccoli@igalia.com> <63a74b56-89ef-8d1f-d487-cdb986aab798@igalia.com> In-Reply-To: <63a74b56-89ef-8d1f-d487-cdb986aab798@igalia.com> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: dlp-product: dlpe-windows dlp-reaction: no-action dlp-version: 11.6.401.20 x-originating-ip: [10.1.200.100] Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 MIME-Version: 1.0 X-Mailman-Approved-At: Tue, 17 May 2022 07:40:39 +1000 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: Paul Mackerras , Pavel Machek , Alexander Gordeev , "K. 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Peter Anvin" , "sparclinux@vger.kernel.org" , "linux-leds@vger.kernel.org" , Anton Ivanov , Richard Weinberger , "x86@kernel.org" , "mingo@redhat.com" , "dyoung@redhat.com" , "paulmck@kernel.org" , Heiko Carstens , "linux-tegra@vger.kernel.org" , "andriy.shevchenko@linux.intel.com" , Johannes Berg , "linux-edac@vger.kernel.org" , "jgross@suse.com" , "netdev@vger.kernel.org" , "kernel@gpiccoli.net" , "kexec@lists.infradead.org" , "linux-mips@vger.kernel.org" , Ivan Kokshaysky , "vkuznets@redhat.com" , "linuxppc-dev@lists.ozlabs.org" Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" PiBTbywgbXkgcmVhc29uaW5nIGhlcmUgaXM6IHRoaXMgbm90aWZpZXIgc2hvdWxkIGZpdCB0aGUg aW5mbyBsaXN0LA0KPiBkZWZpbml0ZWx5ISBCdXQuLi5pdCdzIHZlcnkgaGlnaCByaXNrIGZvciBr ZHVtcC4gSXQgZGVlcCBkaXZlcyBpbnRvIHRoZQ0KPiByZWdtYXAgQVBJICh0aGVyZSBhcmUgbG9j a3MgaW4gc3VjaCBjb2RlKSBwbHVzIHRoZXJlIGlzIGFuIChNTSlJTyB3cml0ZQ0KPiB0byB0aGUg ZGV2aWNlIGFuZCBhbiBBUk0gZmlybXdhcmUgY2FsbC4gU28sIGRlc3BpdGUgdGhlIG5hdHVyZSBv ZiB0aGlzDQo+IG5vdGlmaWVyIF9maXRzIHRoZSBpbmZvcm1hdGlvbmFsIGxpc3RfLCB0aGUgX2Nv ZGUgaXMgcmlza3lfIHNvIHdlIHNob3VsZA0KPiBhdm9pZCBydW5uaW5nIGl0IGJlZm9yZSBhIGtk dW1wLg0KPg0KPiBOb3csIHdlIGluZGVlZCBoYXZlIGEgY2hpY2tlbi9lZ2cgcHJvYmxlbTogd2Fu dCB0byBhdm9pZCBpdCBiZWZvcmUNCj4ga2R1bXAsIEJVVCBpbiBjYXNlIGtkdW1wIGlzIG5vdCBz ZXQsIGttc2dfZHVtcCgpIChhbmQgY29uc29sZSBmbHVzaGluZywNCj4gYWZ0ZXIgeW91ciBzdWdn ZXN0aW9uIFBldHIpIHdpbGwgcnVuIGJlZm9yZSBpdCBhbmQgbm90IHNhdmUgY29sbGVjdGVkDQo+ IGluZm9ybWF0aW9uIGZyb20gRURBQyBQb1YuDQoNCldvdWxkIGl0IGJlIHBvc3NpYmxlIHRvIGhh dmUgc29tZSBnbG9iYWwgImtkdW1wIGlzIGNvbmZpZ3VyZWQgKyBlbmFibGVkIiBmbGFnPw0KDQpU aGVuIG5vdGlmaWVycyBjb3VsZCBtYWtlIGFuIGluZm9ybWVkIGNob2ljZSBvbiB3aGV0aGVyIHRv IGRlZXAgZGl2ZSB0bw0KZ2V0IGFsbCB0aGUgcG9zc2libGUgZGV0YWlscyAod2hlbiB0aGVyZSBp cyBubyBrZHVtcCkgb3IganVzdCBza2ltIHRoZSBoaWdoDQpsZXZlbCBzdHVmZiAodG8gbWF4aW1p emUgY2hhbmNlIG9mIGdldHRpbmcgYSBzdWNjZXNzZnVsIGtkdW1wKS4NCg0KLVRvbnkNCg== From mboxrd@z Thu Jan 1 00:00:00 1970 From: Luck, Tony Date: Mon, 16 May 2022 16:18:04 +0000 Subject: [PATCH 21/30] panic: Introduce the panic pre-reboot notifier list In-Reply-To: <63a74b56-89ef-8d1f-d487-cdb986aab798@igalia.com> References: <20220427224924.592546-1-gpiccoli@igalia.com> <20220427224924.592546-22-gpiccoli@igalia.com> <63a74b56-89ef-8d1f-d487-cdb986aab798@igalia.com> Message-ID: List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: kexec@lists.infradead.org > So, my reasoning here is: this notifier should fit the info list, > definitely! But...it's very high risk for kdump. It deep dives into the > regmap API (there are locks in such code) plus there is an (MM)IO write > to the device and an ARM firmware call. So, despite the nature of this > notifier _fits the informational list_, the _code is risky_ so we should > avoid running it before a kdump. > > Now, we indeed have a chicken/egg problem: want to avoid it before > kdump, BUT in case kdump is not set, kmsg_dump() (and console flushing, > after your suggestion Petr) will run before it and not save collected > information from EDAC PoV. Would it be possible to have some global "kdump is configured + enabled" flag? Then notifiers could make an informed choice on whether to deep dive to get all the possible details (when there is no kdump) or just skim the high level stuff (to maximize chance of getting a successful kdump). -Tony From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: "Luck, Tony" Subject: RE: [PATCH 21/30] panic: Introduce the panic pre-reboot notifier list Date: Mon, 16 May 2022 16:18:04 +0000 Message-ID: References: <20220427224924.592546-1-gpiccoli@igalia.com> <20220427224924.592546-22-gpiccoli@igalia.com> <63a74b56-89ef-8d1f-d487-cdb986aab798@igalia.com> In-Reply-To: <63a74b56-89ef-8d1f-d487-cdb986aab798@igalia.com> Content-Language: en-US MIME-Version: 1.0 List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-um" Errors-To: linux-um-bounces+geert=linux-m68k.org@lists.infradead.org To: "Guilherme G. Piccoli" , Petr Mladek , Dinh Nguyen Cc: "akpm@linux-foundation.org" , "bhe@redhat.com" , "kexec@lists.infradead.org" , "linux-kernel@vger.kernel.org" , "bcm-kernel-feedback-list@broadcom.com" , "linuxppc-dev@lists.ozlabs.org" , "linux-alpha@vger.kernel.org" , "linux-edac@vger.kernel.org" , "linux-hyperv@vger.kernel.org" , "linux-leds@vger.kernel.org" , "linux-mips@vger.kernel.org" , "linux-parisc@vger.kernel.org" , "linux-pm@vger.kernel.org" , "linux-remoteproc@vger.kernel.org" , "linux-s390@vger.kernel.org" , "linux-tegra@vger.kernel.org" , "linux-um@lists.infradead.org" , "linux-xtensa@linux-xtensa.org" , "netdev@vger.kernel.org" , "openipmi-developer@lists.sourceforge.net" , "rcu@vger.kernel.org" , "sparclinux@vger.kernel.org" , "xen-devel@lists.xenproject.org" , "x86@kernel.org" , "kernel-dev@igalia.com" , "kernel@gpiccoli.net" , "halves@canonical.com" , "fabiomirmar@gmail.com" , "alejandro.j.jimenez@oracle.com" , "andriy.shevchenko@linux.intel.com" , "arnd@arndb.de" , "bp@alien8.de" , "corbet@lwn.net" , "d.hatayama@jp.fujitsu.com" , "dave.hansen@linux.intel.com" , "dyoung@redhat.com" , "Tang, Feng" , "gregkh@linuxfoundation.org" , "mikelley@microsoft.com" , "hidehiro.kawai.ez@hitachi.com" , "jgross@suse.com" , "john.ogness@linutronix.de" , "keescook@chromium.org" , "luto@kernel.org" , "mhiramat@kernel.org" , "mingo@redhat.com" , "paulmck@kernel.org" , "peterz@infradead.org" , "rostedt@goodmis.org" , "senozhatsky@chromium.org" , "stern@rowland.harvard.edu" , "tglx@linutronix.de" , "vgoyal@redhat.com" , "vkuznets@redhat.com" , "will@kernel.org" , Alex Elder , Alexander Gordeev , Anton Ivanov , Benjamin Herrenschmidt , Bjorn Andersson , Boris Ostrovsky , Chris Zankel , Christian Borntraeger , "Corey Minyard , Dexuan Cui , H. Peter Anvin , Haiyang Zhang , Heiko Carstens , Helge Deller , Ivan Kokshaysky" , "James E.J. Bottomley" , James Morse , Johannes Berg , "K. Y. Srinivasan" , Mathieu Poirier , "Matt Turner , Mauro Carvalho Chehab , Max Filippov" , Michael Ellerman , Paul Mackerras , Pavel Machek , "Richard Weinberger , Robert Richter , Stefano Stabellini , Stephen Hemminger" , Sven Schnelle , Vasily > So, my reasoning here is: this notifier should fit the info list, > definitely! But...it's very high risk for kdump. It deep dives into the > regmap API (there are locks in such code) plus there is an (MM)IO write > to the device and an ARM firmware call. So, despite the nature of this > notifier _fits the informational list_, the _code is risky_ so we should > avoid running it before a kdump. > > Now, we indeed have a chicken/egg problem: want to avoid it before > kdump, BUT in case kdump is not set, kmsg_dump() (and console flushing, > after your suggestion Petr) will run before it and not save collected > information from EDAC PoV. Would it be possible to have some global "kdump is configured + enabled" flag? Then notifiers could make an informed choice on whether to deep dive to get all the possible details (when there is no kdump) or just skim the high level stuff (to maximize chance of getting a successful kdump). -Tony _______________________________________________ linux-um mailing list linux-um@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-um From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Luck, Tony" Subject: RE: [PATCH 21/30] panic: Introduce the panic pre-reboot notifier list Date: Mon, 16 May 2022 16:18:04 +0000 Message-ID: References: <20220427224924.592546-1-gpiccoli@igalia.com> <20220427224924.592546-22-gpiccoli@igalia.com> <63a74b56-89ef-8d1f-d487-cdb986aab798@igalia.com> Mime-Version: 1.0 Content-Transfer-Encoding: base64 Return-path: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1652717889; x=1684253889; h=from:to:cc:subject:date:message-id:references: in-reply-to:content-transfer-encoding:mime-version; bh=+l+W5AAGJYF9POu96DFeN42Yp1wDBbNs2cT6ebzm1Q4=; b=gE3JndFmb3MVc+y8k0MigjEzVzCqGvTnKuZFhE4DjcCYaU4+iqRdm1YK P0DDqVHBLoq7VKipOO0hdvZYV9pVTZG1CN68yC4Fs1ioVILwIZ3Q2SrMn sSdjpODOS6uWQjCqGoSIJu1pba5omJEmL1FQURGDTGfZUlS1TXhoGF22j h0UKzl3D3f9Sw7CU71YSSLPCDk1YAxt17+ONuVJQaBsvQLE0imNdebkVK Q0O82ERRbpa9leBWTCKvYYiIIzee1lVvNZNkYwosdrYyHDA3KJBcn4HGB Wc7wLsviGum79vhrgzLiyhyPVYTFfrQj6/p9kQjA+0ss/R8t28ygKVZCy A==; In-Reply-To: <63a74b56-89ef-8d1f-d487-cdb986aab798@igalia.com> Content-Language: en-US List-ID: Content-Type: text/plain; charset="us-ascii" To: "Guilherme G. Piccoli" , Petr Mladek , Dinh Nguyen Cc: "akpm@linux-foundation.org" , "bhe@redhat.com" , "kexec@lists.infradead.org" , "linux-kernel@vger.kernel.org" , "bcm-kernel-feedback-list@broadcom.com" , "linuxppc-dev@lists.ozlabs.org" , "linux-alpha@vger.kernel.org" , "linux-edac@vger.kernel.org" , "linux-hyperv@vger.kernel.org" , "linux-leds@vger.kernel.org" , "linux-mips@vger.kernel.org" , "linux-parisc@vger.kernel.org" , "linux-pm@vger.kernel.org" , linux PiBTbywgbXkgcmVhc29uaW5nIGhlcmUgaXM6IHRoaXMgbm90aWZpZXIgc2hvdWxkIGZpdCB0aGUg aW5mbyBsaXN0LA0KPiBkZWZpbml0ZWx5ISBCdXQuLi5pdCdzIHZlcnkgaGlnaCByaXNrIGZvciBr ZHVtcC4gSXQgZGVlcCBkaXZlcyBpbnRvIHRoZQ0KPiByZWdtYXAgQVBJICh0aGVyZSBhcmUgbG9j a3MgaW4gc3VjaCBjb2RlKSBwbHVzIHRoZXJlIGlzIGFuIChNTSlJTyB3cml0ZQ0KPiB0byB0aGUg ZGV2aWNlIGFuZCBhbiBBUk0gZmlybXdhcmUgY2FsbC4gU28sIGRlc3BpdGUgdGhlIG5hdHVyZSBv ZiB0aGlzDQo+IG5vdGlmaWVyIF9maXRzIHRoZSBpbmZvcm1hdGlvbmFsIGxpc3RfLCB0aGUgX2Nv ZGUgaXMgcmlza3lfIHNvIHdlIHNob3VsZA0KPiBhdm9pZCBydW5uaW5nIGl0IGJlZm9yZSBhIGtk dW1wLg0KPg0KPiBOb3csIHdlIGluZGVlZCBoYXZlIGEgY2hpY2tlbi9lZ2cgcHJvYmxlbTogd2Fu dCB0byBhdm9pZCBpdCBiZWZvcmUNCj4ga2R1bXAsIEJVVCBpbiBjYXNlIGtkdW1wIGlzIG5vdCBz ZXQsIGttc2dfZHVtcCgpIChhbmQgY29uc29sZSBmbHVzaGluZywNCj4gYWZ0ZXIgeW91ciBzdWdn ZXN0aW9uIFBldHIpIHdpbGwgcnVuIGJlZm9yZSBpdCBhbmQgbm90IHNhdmUgY29sbGVjdGVkDQo+ IGluZm9ybWF0aW9uIGZyb20gRURBQyBQb1YuDQoNCldvdWxkIGl0IGJlIHBvc3NpYmxlIHRvIGhh dmUgc29tZSBnbG9iYWwgImtkdW1wIGlzIGNvbmZpZ3VyZWQgKyBlbmFibGVkIiBmbGFnPw0KDQpU aGVuIG5vdGlmaWVycyBjb3VsZCBtYWtlIGFuIGluZm9ybWVkIGNob2ljZSBvbiB3aGV0aGVyIHRv IGRlZXAgZGl2ZSB0bw0KZ2V0IGFsbCB0aGUgcG9zc2libGUgZGV0YWlscyAod2hlbiB0aGVyZSBp cyBubyBrZHVtcCkgb3IganVzdCBza2ltIHRoZSBoaWdoDQpsZXZlbCBzdHVmZiAodG8gbWF4aW1p emUgY2hhbmNlIG9mIGdldHRpbmcgYSBzdWNjZXNzZnVsIGtkdW1wKS4NCg0KLVRvbnkNCg==