Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755044AbZJ2O6V (ORCPT ); Thu, 29 Oct 2009 10:58:21 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754841AbZJ2O6V (ORCPT ); Thu, 29 Oct 2009 10:58:21 -0400 Received: from smtp2.ultrahosting.com ([74.213.174.253]:55061 "EHLO smtp.ultrahosting.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1754516AbZJ2O6U (ORCPT ); Thu, 29 Oct 2009 10:58:20 -0400 Date: Thu, 29 Oct 2009 14:57:19 -0400 (EDT) From: Christoph Lameter X-X-Sender: cl@V090114053VZO-1 To: Tejun Heo cc: Jiri Kosina , "Rafael J. Wysocki" , Linux Kernel Mailing List , Kernel Testers List , Ingo Molnar , Jeff Mahoney , "Luck, Tony" , Peter Zijlstra , Peter Zijlstra Subject: Re: [Bug #14467] Linker errors on ia64 with NR_CPUS=4096 In-Reply-To: <4AE9AB23.8010207@kernel.org> Message-ID: References: <6dRYo8ss7vL.A.nnF.Cre5KB@chimera> <4AE9AB23.8010207@kernel.org> User-Agent: Alpine 1.10 (DEB 962 2008-03-14) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1054 Lines: 25 On Thu, 29 Oct 2009, Tejun Heo wrote: > It's just for sched_init() which has irq off but is not really in > atomic context and does GFP_KERNEL allocations. The following comment > has been added to the first patch to explain it. Uhmm.. Is the page allocator available at that point? If you are constricted to the reserved per cpu area then IA64 can still run out of space if its booted with 4096 actual cpus. > + * allocations are done using GFP_KERNEL with pcpu_lock released. In > + * general, percpu memory can't be allocated with irq off but > + * irqsave/restore are still used in alloc path so that it can be used > + * from early init path - sched_init() specifically. > > Thanks. Maybe make the patch a bit more general so that it can operate in an atomic context and handles gfp flags nicely? -- 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/