From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from e4.ny.us.ibm.com ([32.97.182.144]) by canuck.infradead.org with esmtps (Exim 4.63 #1 (Red Hat Linux)) id 1IKwOJ-0004LU-Ln for kexec@lists.infradead.org; Tue, 14 Aug 2007 09:25:04 -0400 Received: from d01relay02.pok.ibm.com (d01relay02.pok.ibm.com [9.56.227.234]) by e4.ny.us.ibm.com (8.13.8/8.13.8) with ESMTP id l7EDOpRh006345 for ; Tue, 14 Aug 2007 09:24:51 -0400 Received: from d01av04.pok.ibm.com (d01av04.pok.ibm.com [9.56.224.64]) by d01relay02.pok.ibm.com (8.13.8/8.13.8/NCO v8.4) with ESMTP id l7EDOpFS459076 for ; Tue, 14 Aug 2007 09:24:51 -0400 Received: from d01av04.pok.ibm.com (loopback [127.0.0.1]) by d01av04.pok.ibm.com (8.12.11.20060308/8.13.3) with ESMTP id l7EDOoAx002596 for ; Tue, 14 Aug 2007 09:24:50 -0400 Date: Tue, 14 Aug 2007 18:54:54 +0530 From: Vivek Goyal Subject: Re: [patch] add kdump_after_notifier Message-ID: <20070814132454.GA8293@in.ibm.com> References: <20070802112852.GA7054@in.ibm.com> <31687.1186113947@kao2.melbourne.sgi.com> <20070805110746.GA12540@in.ibm.com> <46C1691E.7090708@ah.jp.nec.com> <20070814083710.GA14538@suse.de> Mime-Version: 1.0 Content-Disposition: inline In-Reply-To: <20070814083710.GA14538@suse.de> Reply-To: vgoyal@in.ibm.com 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-bounces@lists.infradead.org Errors-To: kexec-bounces+dwmw2=infradead.org+dwmw2=infradead.org@lists.infradead.org To: Takenori Nagano , Keith Owens , "Eric W. Biederman" , k-miyoshi@cb.jp.nec.com, kexec@lists.infradead.org, linux-kernel@vger.kernel.org, Andrew Morton T24gVHVlLCBBdWcgMTQsIDIwMDcgYXQgMTA6Mzc6MTBBTSArMDIwMCwgQmVybmhhcmQgV2FsbGUg d3JvdGU6Cj4gKiBUYWtlbm9yaSBOYWdhbm8gPHQtbmFnYW5vQGFoLmpwLm5lYy5jb20+IFsyMDA3 LTA4LTE0IDEwOjM0XToKPiA+IFZpdmVrIEdveWFsIHdyb3RlOgo+ID4gPiBPbiBGcmksIEF1ZyAw MywgMjAwNyBhdCAwMjowNTo0N1BNICsxMDAwLCBLZWl0aCBPd2VucyB3cm90ZToKPiA+ID4gCj4g PiA+IAo+ID4gPiBUbyBzdW0gdXAsIGNvdXBsZSBvZiBvcHRpb25zIGNvbWUgdG8gbWluZC4KPiA+ ID4gCj4gPiA+IC0gUmVnaXN0ZXIgYWxsIHRoZSBSQVMgdG9vbHMgb24gZGllIG5vdGlmaWVyIGFu ZCBwYW5pYwo+ID4gPiAgIG5vdGlmaWVyIGxpc3RzIHdpdGggZmFpcmx5IGhpZ2ggcHJpb3JpdHku IEV4cG9ydCBsaXN0Cj4gPiA+ICAgb2YgUkFTIHRvb2xzIHRvIHVzZXIgc3BhY2UgYW5kIGFsbG93 IHVzZXJzIHRvIGRlY2lkZSB0aGUKPiA+ID4gICBvcmRlciBvZiBleGVjdXRpb24gYW5kIHByaW9y aXR5IG9mIFJBUyB0b29scy4KPiA+ID4gCj4gPiA+IC0gQ3JlYXRlIGEgc2VwYXJhdGUgUkFTIHRv b2wgbm90aWZpZXIgbGlzdCAocmFzX3Rvb2xfbm90aWZlcl9saXN0KS4KPiA+ID4gICBBbGwgdGhl IFJBUyB0b29scyByZWdpc3RlciBvbiB0aGlzIGxpc3QuIFRoaXMgbGlzdCBnZXRzIHByaW9yaXR5 Cj4gPiA+ICAgb3ZlciBkaWUgb3IgcGFuaWMgbm90aWZpZXIgbGlzdC4gVXNlciBkZWNpZGVzIHRo ZSBvZGVyIG9mIGV4ZWN1dGlvbgo+ID4gPiAgIG9mIFJBUyB0b29scy4gCj4gPiA+IAo+ID4gPiAg IEhlcmUgYXNzdW1wdGlvbiBpcyB0aGF0IGFib3ZlIGxpc3Qgd2lsbCBub3QgYmUgZXhwb3J0ZWQg dG8gbW9kdWxlcy4KPiA+ID4gICBBbGwgdGhlIFJBUyB0b29scyB3aWxsIGJlIGluIGtlcm5lbCBh bmQgdGhleSBhbHdheXMgZ2V0IGEgcHJpb3JpdHkKPiA+ID4gICB0byBpbnNwZWN0IGFuIGV2ZW50 Lgo+ID4gPiAKPiA+ID4gV2hhdCBkbyBvdGhlcnMgdGhpbms/Cj4gPiAKPiA+IFZlcnkgZ29vZCBp ZGVhLiBCdXQgdGhlcmUgaXMgYSBwcm9ibGVtIGhvdyB0byBnaXZlIGRlZmF1bHQgcHJpb3JpdHkg dG8gUkFTIHRvb2xzLgo+ID4gCj4gPiBIb3cgYWJvdXQgcHJpb3JpdHkgY2hhbmdlYWJsZSBub3Rp Zmllcl9saXN0PyBVc2VyIGNhbiBjaGFuZ2UgbGlzdCBvcmRlcgo+ID4gZHluYW1pY2FsbHkgaWYg dGhleSB3YW50LiBPZiBjb3Vyc2UsIHdlIGhhdmUgdG8gZ2l2ZSBoaWdoZXN0IHByaW9yaXR5IHRv IGtkdW1wCj4gPiBieSBkZWZhdWx0LiBJdCBpcyB2ZXJ5IHVzZWZ1bCBmb3IgdXNlcnMgd2hvIHdh bnQgdG8gdXNlIHNvbWUgUkFTIHRvb2xzLgo+IAo+IEkgdGhpbmsgdGhhdCB3YXMgdGhlIGlkZWEg b2YgdGhlIGZpcnN0IOKAnC3igJ0gKOKAnGV4cG9ydCBsaXN0IG9mIFJBUyB0b29scwo+IHRvIHVz ZXIgc3BhY2XigJ0pLgo+IAoKU28gZm9yIHRoZSB0aW1lIGJlaW5nIEkgdGhpbmsgd2UgY2FuIHB1 dCBSQVMgdG9vbHMgb24gZGllIG5vdGlmaWVyIGxpc3QKYW5kIGlmIGl0IHJ1bnMgaW50byBpc3N1 ZXMgd2UgY2FuIGFsd2F5cyB0aGluayBvZiBjcmVhdGluZyBhIHNlcGFyYXRlIGxpc3QuCgpGZXcg dGhpbmdzIGNvbWUgdG8gbWluZC4KCi0gV2h5IHRoZXJlIGlzIGEgc2VwYXJhdGUgcGFuaWNfbm90 aWZpZXJfbGlzdD8gQ2FuJ3QgaXQgYmUgbWVyZ2VkIHdpdGgKICBkaWVfY2hhaW4/IGRpZV92YWwg YWxyZWFkeSBnb3Qgb25lIG9mIHRoZSBldmVudCB0eXBlIGFzIFBBTklDLiBJZiB0aGVyZQogIGFy ZSBubyBzcGVjaWZpYyByZWFzb25zIHRoZW4gd2Ugc2hvdWxkIG1lcmdlIHRoZSB0d28gbGlzdHMu IFJlZ2lzdGVyaW5nCiAgUkFTIHRvb2xzIG9uIGEgc2luZ2xlIGxpc3QgaXMgZWFzaWVyLgotIE1v ZGlmeSBLZHVtcCB0byByZWdpc3RlciBvbiBkaWVfY2hhaW4gbGlzdC4gCi0gTW9kaWZ5IEtkYiB0 byByZWdpc3RlciBvbiBkaWVfY2hhaW4gbGlzdC4KLSBFeHBvcnQgYWxsIHRoZSByZWdpc3RlcmVk IG1lbWJlcnMgb2YgZGllX2NoYWluIHRocm91Z2ggc3lzZnMgYWxvbmcgd2l0aAogIHRoZWlyIHBy aW9yaXRpZXMuIFByaW9yaXRpZXMgc2hvdWxkIGJlIG1vZGlmaWFibGUuIE1vc3QgbGlrZWx5IG9u ZSAKICBzaGFsbCBoYXZlIHRvIGludHJvZHVjZSBhZGRpdGlvbmFsIGZpZWxkIGluIHN0cnVjdCBu b3RpZmllcl9ibG9jay4gVGhpcwogIGZpZWxkIHdpbGwgYmUgYSBzdHJpbmcgYXMgYW4gaWRlbnRp ZmllciBvZiB0aGUgdXNlciByZWdpc3RlcmQuIGUuZwogICJLZHVtcCIsICJLZGIiIGV0Yy4KCk5v dyB1c2VyIHdpbGwgYmUgYWJsZSB0byB2aWV3IGFsbCB0aGUgZGllX2NoYWluIHVzZXJzIHRocm91 Z2ggc3lzZnMgYW5kCmJlIGFibGUgdG8gbW9kaWZ5IHRoZSBvcmRlciBpbiB3aGljaCB0aGVzZSBz aG91bGQgcnVuIGJ5IG1vZGlmeWluZyB0aGVpcgpwcmlvcml0eS4gSGVuY2UgYWxsIHRoZSBSQVMg dG9vbHMgY2FuIGNvLWV4aXN0LgoKQW55IHRob3VnaHRzPwoKVGhhbmtzClZpdmVrCgoKCgo+IAo+ IFRoYW5rcywKPiAgICBCZXJuaGFyZAoKX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19f X19fX19fX19fX19fX18Ka2V4ZWMgbWFpbGluZyBsaXN0CmtleGVjQGxpc3RzLmluZnJhZGVhZC5v cmcKaHR0cDovL2xpc3RzLmluZnJhZGVhZC5vcmcvbWFpbG1hbi9saXN0aW5mby9rZXhlYwo= From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761445AbXHNNZK (ORCPT ); Tue, 14 Aug 2007 09:25:10 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756923AbXHNNYy (ORCPT ); Tue, 14 Aug 2007 09:24:54 -0400 Received: from e3.ny.us.ibm.com ([32.97.182.143]:41586 "EHLO e3.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752338AbXHNNYw (ORCPT ); Tue, 14 Aug 2007 09:24:52 -0400 Date: Tue, 14 Aug 2007 18:54:54 +0530 From: Vivek Goyal To: Takenori Nagano , Keith Owens , "Eric W. Biederman" , k-miyoshi@cb.jp.nec.com, kexec@lists.infradead.org, linux-kernel@vger.kernel.org, Andrew Morton Subject: Re: [patch] add kdump_after_notifier Message-ID: <20070814132454.GA8293@in.ibm.com> Reply-To: vgoyal@in.ibm.com References: <20070802112852.GA7054@in.ibm.com> <31687.1186113947@kao2.melbourne.sgi.com> <20070805110746.GA12540@in.ibm.com> <46C1691E.7090708@ah.jp.nec.com> <20070814083710.GA14538@suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20070814083710.GA14538@suse.de> User-Agent: Mutt/1.5.11 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Aug 14, 2007 at 10:37:10AM +0200, Bernhard Walle wrote: > * Takenori Nagano [2007-08-14 10:34]: > > Vivek Goyal wrote: > > > On Fri, Aug 03, 2007 at 02:05:47PM +1000, Keith Owens wrote: > > > > > > > > > To sum up, couple of options come to mind. > > > > > > - Register all the RAS tools on die notifier and panic > > > notifier lists with fairly high priority. Export list > > > of RAS tools to user space and allow users to decide the > > > order of execution and priority of RAS tools. > > > > > > - Create a separate RAS tool notifier list (ras_tool_notifer_list). > > > All the RAS tools register on this list. This list gets priority > > > over die or panic notifier list. User decides the oder of execution > > > of RAS tools. > > > > > > Here assumption is that above list will not be exported to modules. > > > All the RAS tools will be in kernel and they always get a priority > > > to inspect an event. > > > > > > What do others think? > > > > Very good idea. But there is a problem how to give default priority to RAS tools. > > > > How about priority changeable notifier_list? User can change list order > > dynamically if they want. Of course, we have to give highest priority to kdump > > by default. It is very useful for users who want to use some RAS tools. > > I think that was the idea of the first “-” (“export list of RAS tools > to user space”). > So for the time being I think we can put RAS tools on die notifier list and if it runs into issues we can always think of creating a separate list. Few things come to mind. - Why there is a separate panic_notifier_list? Can't it be merged with die_chain? die_val already got one of the event type as PANIC. If there are no specific reasons then we should merge the two lists. Registering RAS tools on a single list is easier. - Modify Kdump to register on die_chain list. - Modify Kdb to register on die_chain list. - Export all the registered members of die_chain through sysfs along with their priorities. Priorities should be modifiable. Most likely one shall have to introduce additional field in struct notifier_block. This field will be a string as an identifier of the user registerd. e.g "Kdump", "Kdb" etc. Now user will be able to view all the die_chain users through sysfs and be able to modify the order in which these should run by modifying their priority. Hence all the RAS tools can co-exist. Any thoughts? Thanks Vivek > > Thanks, > Bernhard