From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.cs.helsinki.fi (courier.cs.helsinki.fi [128.214.9.1]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTP id 30020DE292 for ; Wed, 5 Mar 2008 07:45:38 +1100 (EST) Message-ID: <47CDB498.6040003@cs.helsinki.fi> Date: Tue, 04 Mar 2008 22:44:08 +0200 From: Pekka Enberg MIME-Version: 1.0 To: Andrew Morton Subject: Re: [BUG] 2.6.25-rc3-mm1 kernel panic while bootup on powerpc () References: <20080304011928.e8c82c0c.akpm@linux-foundation.org> <47CD4AB3.3080409@linux.vnet.ibm.com> <20080304103636.3e7b8fdd.akpm@linux-foundation.org> <47CDA081.7070503@cs.helsinki.fi> <20080304193532.GC9051@csn.ul.ie> <84144f020803041141x5bb55832r495d7fde92356e27@mail.gmail.com> <20080304123459.364f879b.akpm@linux-foundation.org> In-Reply-To: <20080304123459.364f879b.akpm@linux-foundation.org> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Cc: linux-mm@kvack.org, mel@csn.ul.ie, kamalesh@linux.vnet.ibm.com, linuxppc-dev@ozlabs.org, stable@kernel.org, Christoph Lameter List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Andrew Morton wrote: > On Tue, 4 Mar 2008 12:07:39 -0800 (PST) > Christoph Lameter wrote: > >> I think this is the correct fix. >> >> The NUMA fallback logic should be passing local_flags to kmem_get_pages() >> and not simply the flags. >> >> Maybe a stable candidate since we are now simply >> passing on flags to the page allocator on the fallback path. > > Do we know why this is only reported in 2.6.25-rc3-mm1? > > Why does this need fixing in 2.6.24.x? Looking at the code, it's triggerable in 2.6.24.3 at least. Why we don't have a report yet, probably because (1) the default allocator is SLUB which doesn't suffer from this and (2) you need a big honkin' NUMA box that causes fallback allocations to happen to trigger it. Pekka