From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from e23smtp05.au.ibm.com (E23SMTP05.au.ibm.com [202.81.18.174]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "e23smtp05.au.ibm.com", Issuer "Equifax" (verified OK)) by ozlabs.org (Postfix) with ESMTP id 1F412DDE3F for ; Wed, 20 Feb 2008 00:19:28 +1100 (EST) Received: from d23relay03.au.ibm.com (d23relay03.au.ibm.com [202.81.18.234]) by e23smtp05.au.ibm.com (8.13.1/8.13.1) with ESMTP id m1JDJDUP008909 for ; Wed, 20 Feb 2008 00:19:13 +1100 Received: from d23av02.au.ibm.com (d23av02.au.ibm.com [9.190.235.138]) by d23relay03.au.ibm.com (8.13.8/8.13.8/NCO v8.7) with ESMTP id m1JDJS8m3956836 for ; Wed, 20 Feb 2008 00:19:28 +1100 Received: from d23av02.au.ibm.com (loopback [127.0.0.1]) by d23av02.au.ibm.com (8.12.11.20060308/8.13.3) with ESMTP id m1JDJRPL004069 for ; Wed, 20 Feb 2008 00:19:28 +1100 Message-ID: <47BAD75C.9030406@linux.vnet.ibm.com> Date: Tue, 19 Feb 2008 18:49:24 +0530 From: Kamalesh Babulal MIME-Version: 1.0 To: Jens Axboe Subject: Re: [BUG] Linux 2.6.25-rc2 - Regression from 2.6.24-rc1-git1 softlockup while bootup on powerpc References: <47B67E5E.4010001@linux.vnet.ibm.com> <20080217192913.GO23197@kernel.dk> <20080219170432.9c04376f.kamezawa.hiroyu@jp.fujitsu.com> <20080219083633.GN23197@kernel.dk> In-Reply-To: <20080219083633.GN23197@kernel.dk> Content-Type: text/plain; charset=us-ascii Cc: Dhaval Giani , Linux Kernel Mailing List , Srivatsa Vaddagiri , linuxppc-dev@ozlabs.org, Ingo Molnar , KAMEZAWA Hiroyuki , Balbir Singh List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Jens Axboe wrote: > On Tue, Feb 19 2008, KAMEZAWA Hiroyuki wrote: >> On Sun, 17 Feb 2008 20:29:13 +0100 >> Jens Axboe wrote: >> >>> It's odd stuff. Could you perhaps try and add some printks to >>> block/cfq-iosched.c:call_for_each_cic(), like dumping the 'nr' return >>> from radix_tree_gang_lookup() and the pointer value of cics[i] in the >>> for() loop after the lookup? >>> >> I met the same issue on ia64/NUMA box. >> seems cisc[]->key is NULL and index for radix_tree_gang_lookup() was >> always '1'. > > Why does it keep repeating then? If ->key is NULL, the next lookup index > should be 1UL. > > But I think the radix 'scan over entire tree' is a bit fragile. This > patch adds a parallel hlist for ease of properly browsing the members, > does that work for you? It compiles, but I haven't booted it here yet... > >> Attached patch works well for me, but I don't know much about cfq. >> please confirm. > > It doesn't make a lot of sense, I'm afraid. > > block/blk-ioc.c | 35 +++++++++++++++-------------------- > block/cfq-iosched.c | 37 +++++++++++-------------------------- > include/linux/iocontext.h | 2 ++ > 3 files changed, 28 insertions(+), 46 deletions(-) > > diff --git a/block/blk-ioc.c b/block/blk-ioc.c > index 80245dc..73c7002 100644 > --- a/block/blk-ioc.c Hi Jens, Thanks for the patch. The patch works fine, machine boots up without the kernel panic. -- Thanks & Regards, Kamalesh Babulal, Linux Technology Center, IBM, ISTL.