From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757521Ab3CHNCx (ORCPT ); Fri, 8 Mar 2013 08:02:53 -0500 Received: from mail-wg0-f50.google.com ([74.125.82.50]:46711 "EHLO mail-wg0-f50.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757108Ab3CHNCv convert rfc822-to-8bit (ORCPT ); Fri, 8 Mar 2013 08:02:51 -0500 MIME-Version: 1.0 In-Reply-To: <20130308.105519.82764856.d.hatayama@jp.fujitsu.com> References: <20130302083447.31252.93914.stgit@localhost6.localdomain6> <20130302083714.31252.17863.stgit@localhost6.localdomain6> <513867D2.7090501@cn.fujitsu.com> <20130308.105519.82764856.d.hatayama@jp.fujitsu.com> Date: Fri, 8 Mar 2013 21:02:50 +0800 Message-ID: Subject: Re: [PATCH v2 15/20] kexec: fill note buffers by NT_VMCORE_PAD notes in page-size boundary From: Yanfei Zhang To: HATAYAMA Daisuke Cc: zhangyanfei@cn.fujitsu.com, kexec@lists.infradead.org, heiko.carstens@de.ibm.com, linux-kernel@vger.kernel.org, lisa.mitchell@hp.com, kumagai-atsushi@mxc.nes.nec.co.jp, ebiederm@xmission.com, akpm@linux-foundation.org, cpw@sgi.com, vgoyal@redhat.com Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2013/3/8 HATAYAMA Daisuke : > From: Zhang Yanfei > Subject: Re: [PATCH v2 15/20] kexec: fill note buffers by NT_VMCORE_PAD notes in page-size boundary > Date: Thu, 7 Mar 2013 18:11:30 +0800 > >> 于 2013年03月02日 16:37, HATAYAMA Daisuke 写道: >>> Fill both crash_notes and vmcoreinfo_note buffers by NT_VMCORE_PAD >>> note type to make them satisfy mmap()'s page-size boundary >>> requirement. >>> >>> So far, end of note segments has been marked by zero-filled elf >>> header. Instead, this patch writes NT_VMCORE_PAD note in the end of >>> note segments until the offset on page-size boundary. >> >> >> In the codes below, it seems that you assign name "VMCOREINFO" for >> note type NT_VMCORE_PAD, right? This is kind of wired, i think. This >> name has been used for NT_VMCORE_DEBUGINFO note already. Why not something >> like "VMCOREPAD" or "PAD"? >> > > It looks you are confusing or don't know name and type. The name is > namespace and in the namespace, there are multiple note types, each of > which has the corresponding data. In other words, data corresponding > to types differ if they belong to differnet name space even if > integers of the types are coincide with. Yes, I knew this. Just as the spec said " a program must recognize both the name and the type to recognize a descriptor.". But I cannot understand what your word "namespace" came from? I think you complicate simple things here. Only with a type, we cannot recognize a descriptor, because "multiple interpretations of a single type value may exist", So we should combine the name and the type together. If both the name and type of two descriptors are the same, we could say we have two same descriptors. If one of them (type or name) are different, we say the two descriptors are different and the two notes have different data. If I am wrong, please correct me. > > The "VMCOREINFO" name represents information exported from > /proc/vmcore that is used in kdump framework. In this sense, > NT_VMCORE_PAD that is specific for /proc/vmcore and kdump framework, > should belong to the "VMCOREINFO" name. I cannot understand the name explanation totally. Does the name really have this meaning? Is there any authentic document? I was always thinking we could feel free to name a name by ourselves! > > Thanks. > HATAYAMA, Daisuke > > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mail-wg0-f46.google.com ([74.125.82.46]) by merlin.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1UDwwq-0000MD-C9 for kexec@lists.infradead.org; Fri, 08 Mar 2013 13:03:03 +0000 Received: by mail-wg0-f46.google.com with SMTP id fg15so2418086wgb.25 for ; Fri, 08 Mar 2013 05:02:51 -0800 (PST) MIME-Version: 1.0 In-Reply-To: <20130308.105519.82764856.d.hatayama@jp.fujitsu.com> References: <20130302083447.31252.93914.stgit@localhost6.localdomain6> <20130302083714.31252.17863.stgit@localhost6.localdomain6> <513867D2.7090501@cn.fujitsu.com> <20130308.105519.82764856.d.hatayama@jp.fujitsu.com> Date: Fri, 8 Mar 2013 21:02:50 +0800 Message-ID: Subject: Re: [PATCH v2 15/20] kexec: fill note buffers by NT_VMCORE_PAD notes in page-size boundary From: Yanfei Zhang List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Sender: "kexec" Errors-To: kexec-bounces+dwmw2=infradead.org@lists.infradead.org To: HATAYAMA Daisuke Cc: heiko.carstens@de.ibm.com, kexec@lists.infradead.org, linux-kernel@vger.kernel.org, lisa.mitchell@hp.com, kumagai-atsushi@mxc.nes.nec.co.jp, ebiederm@xmission.com, zhangyanfei@cn.fujitsu.com, akpm@linux-foundation.org, cpw@sgi.com, vgoyal@redhat.com MjAxMy8zLzggSEFUQVlBTUEgRGFpc3VrZSA8ZC5oYXRheWFtYUBqcC5mdWppdHN1LmNvbT46Cj4g RnJvbTogWmhhbmcgWWFuZmVpIDx6aGFuZ3lhbmZlaUBjbi5mdWppdHN1LmNvbT4KPiBTdWJqZWN0 OiBSZTogW1BBVENIIHYyIDE1LzIwXSBrZXhlYzogZmlsbCBub3RlIGJ1ZmZlcnMgYnkgTlRfVk1D T1JFX1BBRCBub3RlcyBpbiBwYWdlLXNpemUgYm91bmRhcnkKPiBEYXRlOiBUaHUsIDcgTWFyIDIw MTMgMTg6MTE6MzAgKzA4MDAKPgo+PiDkuo4gMjAxM+W5tDAz5pyIMDLml6UgMTY6MzcsIEhBVEFZ QU1BIERhaXN1a2Ug5YaZ6YGTOgo+Pj4gRmlsbCBib3RoIGNyYXNoX25vdGVzIGFuZCB2bWNvcmVp bmZvX25vdGUgYnVmZmVycyBieSBOVF9WTUNPUkVfUEFECj4+PiBub3RlIHR5cGUgdG8gbWFrZSB0 aGVtIHNhdGlzZnkgbW1hcCgpJ3MgcGFnZS1zaXplIGJvdW5kYXJ5Cj4+PiByZXF1aXJlbWVudC4K Pj4+Cj4+PiBTbyBmYXIsIGVuZCBvZiBub3RlIHNlZ21lbnRzIGhhcyBiZWVuIG1hcmtlZCBieSB6 ZXJvLWZpbGxlZCBlbGYKPj4+IGhlYWRlci4gSW5zdGVhZCwgdGhpcyBwYXRjaCB3cml0ZXMgTlRf Vk1DT1JFX1BBRCBub3RlIGluIHRoZSBlbmQgb2YKPj4+IG5vdGUgc2VnbWVudHMgdW50aWwgdGhl IG9mZnNldCBvbiBwYWdlLXNpemUgYm91bmRhcnkuCj4+Cj4+Cj4+IEluIHRoZSBjb2RlcyBiZWxv dywgaXQgc2VlbXMgdGhhdCB5b3UgYXNzaWduIG5hbWUgIlZNQ09SRUlORk8iIGZvcgo+PiBub3Rl IHR5cGUgTlRfVk1DT1JFX1BBRCwgcmlnaHQ/IFRoaXMgaXMga2luZCBvZiB3aXJlZCwgaSB0aGlu ay4gVGhpcwo+PiBuYW1lIGhhcyBiZWVuIHVzZWQgZm9yIE5UX1ZNQ09SRV9ERUJVR0lORk8gbm90 ZSBhbHJlYWR5LiBXaHkgbm90IHNvbWV0aGluZwo+PiBsaWtlICJWTUNPUkVQQUQiIG9yICJQQUQi Pwo+Pgo+Cj4gSXQgbG9va3MgeW91IGFyZSBjb25mdXNpbmcgb3IgZG9uJ3Qga25vdyBuYW1lIGFu ZCB0eXBlLiBUaGUgbmFtZSBpcwo+IG5hbWVzcGFjZSBhbmQgaW4gdGhlIG5hbWVzcGFjZSwgdGhl cmUgYXJlIG11bHRpcGxlIG5vdGUgdHlwZXMsIGVhY2ggb2YKPiB3aGljaCBoYXMgdGhlIGNvcnJl c3BvbmRpbmcgZGF0YS4gSW4gb3RoZXIgd29yZHMsIGRhdGEgY29ycmVzcG9uZGluZwo+IHRvIHR5 cGVzIGRpZmZlciBpZiB0aGV5IGJlbG9uZyB0byBkaWZmZXJuZXQgbmFtZSBzcGFjZSBldmVuIGlm Cj4gaW50ZWdlcnMgb2YgdGhlIHR5cGVzIGFyZSBjb2luY2lkZSB3aXRoLgoKWWVzLCBJIGtuZXcg dGhpcy4gSnVzdCBhcyB0aGUgc3BlYyBzYWlkICIgYSBwcm9ncmFtIG11c3QgcmVjb2duaXplIGJv dGggdGhlIG5hbWUKYW5kIHRoZSB0eXBlIHRvIHJlY29nbml6ZSBhIGRlc2NyaXB0b3IuIi4gQnV0 IEkgY2Fubm90IHVuZGVyc3RhbmQgd2hhdCB5b3VyIHdvcmQKIm5hbWVzcGFjZSIgY2FtZSBmcm9t PyBJIHRoaW5rIHlvdSBjb21wbGljYXRlIHNpbXBsZSB0aGluZ3MgaGVyZS4KCk9ubHkgd2l0aCBh IHR5cGUsIHdlIGNhbm5vdCByZWNvZ25pemUgYSBkZXNjcmlwdG9yLCBiZWNhdXNlICJtdWx0aXBs ZQppbnRlcnByZXRhdGlvbnMgb2YKYSBzaW5nbGUgdHlwZSB2YWx1ZSBtYXkgZXhpc3QiLCBTbyB3 ZSBzaG91bGQgY29tYmluZSB0aGUgbmFtZSBhbmQgdGhlIHR5cGUKdG9nZXRoZXIuIElmIGJvdGgg dGhlIG5hbWUgYW5kIHR5cGUgb2YgdHdvIGRlc2NyaXB0b3JzIGFyZSB0aGUgc2FtZSwKd2UgY291 bGQgc2F5IHdlCmhhdmUgdHdvIHNhbWUgZGVzY3JpcHRvcnMuIElmIG9uZSBvZiB0aGVtICh0eXBl IG9yIG5hbWUpIGFyZQpkaWZmZXJlbnQsIHdlIHNheSB0aGUKdHdvIGRlc2NyaXB0b3JzIGFyZSBk aWZmZXJlbnQgYW5kIHRoZSB0d28gbm90ZXMgaGF2ZSBkaWZmZXJlbnQgZGF0YS4KCklmIEkgYW0g d3JvbmcsIHBsZWFzZSBjb3JyZWN0IG1lLgoKPgo+IFRoZSAiVk1DT1JFSU5GTyIgbmFtZSByZXBy ZXNlbnRzIGluZm9ybWF0aW9uIGV4cG9ydGVkIGZyb20KPiAvcHJvYy92bWNvcmUgdGhhdCBpcyB1 c2VkIGluIGtkdW1wIGZyYW1ld29yay4gSW4gdGhpcyBzZW5zZSwKPiBOVF9WTUNPUkVfUEFEIHRo YXQgaXMgc3BlY2lmaWMgZm9yIC9wcm9jL3ZtY29yZSBhbmQga2R1bXAgZnJhbWV3b3JrLAo+IHNo b3VsZCBiZWxvbmcgdG8gdGhlICJWTUNPUkVJTkZPIiBuYW1lLgoKSSBjYW5ub3QgdW5kZXJzdGFu ZCB0aGUgbmFtZSBleHBsYW5hdGlvbiB0b3RhbGx5LiBEb2VzIHRoZSBuYW1lIHJlYWxseQpoYXZl IHRoaXMgbWVhbmluZz8gSXMgdGhlcmUgYW55IGF1dGhlbnRpYyBkb2N1bWVudD8gSSB3YXMgYWx3 YXlzIHRoaW5raW5nIHdlCmNvdWxkIGZlZWwgZnJlZSB0byBuYW1lIGEgbmFtZSBieSBvdXJzZWx2 ZXMhCgo+Cj4gVGhhbmtzLgo+IEhBVEFZQU1BLCBEYWlzdWtlCj4KPiAtLQo+IFRvIHVuc3Vic2Ny aWJlIGZyb20gdGhpcyBsaXN0OiBzZW5kIHRoZSBsaW5lICJ1bnN1YnNjcmliZSBsaW51eC1rZXJu ZWwiIGluCj4gdGhlIGJvZHkgb2YgYSBtZXNzYWdlIHRvIG1ham9yZG9tb0B2Z2VyLmtlcm5lbC5v cmcKPiBNb3JlIG1ham9yZG9tbyBpbmZvIGF0ICBodHRwOi8vdmdlci5rZXJuZWwub3JnL21ham9y ZG9tby1pbmZvLmh0bWwKPiBQbGVhc2UgcmVhZCB0aGUgRkFRIGF0ICBodHRwOi8vd3d3LnR1eC5v cmcvbGttbC8KCl9fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19f CmtleGVjIG1haWxpbmcgbGlzdAprZXhlY0BsaXN0cy5pbmZyYWRlYWQub3JnCmh0dHA6Ly9saXN0 cy5pbmZyYWRlYWQub3JnL21haWxtYW4vbGlzdGluZm8va2V4ZWMK