From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail172.messagelabs.com (mail172.messagelabs.com [216.82.254.3]) by kanga.kvack.org (Postfix) with SMTP id 588E98D0040 for ; Thu, 24 Mar 2011 14:13:41 -0400 (EDT) Date: Thu, 24 Mar 2011 20:13:18 +0200 (EET) From: Pekka Enberg Subject: Re: [GIT PULL] SLAB changes for v2.6.39-rc1 In-Reply-To: <20110324172653.GA28507@elte.hu> Message-ID: References: <20110324142146.GA11682@elte.hu> <20110324172653.GA28507@elte.hu> MIME-Version: 1.0 Content-Type: MULTIPART/MIXED; BOUNDARY="8323329-1280347503-1300990398=:4990" Sender: owner-linux-mm@kvack.org List-ID: To: Ingo Molnar Cc: Christoph Lameter , torvalds@linux-foundation.org, akpm@linux-foundation.org, tj@kernel.org, npiggin@kernel.dk, rientjes@google.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org This message is in MIME format. The first part should be readable text, while the remaining parts are likely unreadable without MIME-aware tools. --8323329-1280347503-1300990398=:4990 Content-Type: TEXT/PLAIN; charset=iso-8859-1; format=flowed Content-Transfer-Encoding: 8BIT Hi Ingo, On Thu, 24 Mar 2011, Ingo Molnar wrote: > * Pekka Enberg wrote: > >> On Thu, Mar 24, 2011 at 4:41 PM, Christoph Lameter wrote: >>> On Thu, 24 Mar 2011, Ingo Molnar wrote: >>> >>>> FYI, some sort of boot crash has snuck upstream in the last 24 hours: >>>> >>>> BUG: unable to handle kernel paging request at ffff87ffc147e020 >>>> IP: [] this_cpu_cmpxchg16b_emu+0x2/0x1c >>> >>> Hmmm.. This is the fallback code for the case that the processor does not >>> support cmpxchg16b. >> >> How does alternative_io() work? Does it require >> alternative_instructions() to be executed. If so, the fallback code >> won't be active when we enter kmem_cache_init(). Is there any reason >> check_bugs() is called so late during boot? Can we do something like >> the totally untested attached patch? > > Does the config i sent you boot on your box? I think the bug is pretty generic > and should trigger on any box. Here's a patch that reorganizes the alternatives fixup to happen earlier so that the fallback should work. It boots on my machine so please give it a spin if possible. I'll try out your .config next. Pekka --8323329-1280347503-1300990398=:4990--