From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from gate.crashing.org (gate.crashing.org [63.228.1.57]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id 98880DE0BD for ; Fri, 10 Oct 2008 16:02:44 +1100 (EST) Subject: Re: [PATCH v3] powerpc: properly reserve in bootmem the lmb reserved regions that cross NUMA nodes From: Benjamin Herrenschmidt To: Jon Tollefson In-Reply-To: <48EE6720.6010601@linux.vnet.ibm.com> References: <48EE6720.6010601@linux.vnet.ibm.com> Content-Type: text/plain Date: Fri, 10 Oct 2008 15:55:16 +1100 Message-Id: <1223614516.8157.154.camel@pasglop> Mime-Version: 1.0 Cc: Linux Memory Management List , Linux Kernel Mailing List , linuxppc-dev , Paul Mackerras Reply-To: benh@kernel.crashing.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Thu, 2008-10-09 at 15:18 -0500, Jon Tollefson wrote: > If there are multiple reserved memory blocks via lmb_reserve() that are > contiguous addresses and on different NUMA nodes we are losing track of which > address ranges to reserve in bootmem on which node. I discovered this > when I recently got to try 16GB huge pages on a system with more then 2 nodes. I'm going to apply it, however, could you double check something for me ? A cursory glance of the new version makes me wonder, what if the first call to get_node_active_region() ends up with the work_fn never hitting the if () case ? I think in that case, node_ar->end_pfn never gets initialized right ? Can that happen in practice ? I suspect that isn't the case but better safe than sorry... If there's indeed a potential problem, please send a fixup patch. Cheers, Ben.