Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754263AbbDMNiz (ORCPT ); Mon, 13 Apr 2015 09:38:55 -0400 Received: from forward-corp1g.mail.yandex.net ([95.108.253.251]:38613 "EHLO forward-corp1g.mail.yandex.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750999AbbDMNix (ORCPT ); Mon, 13 Apr 2015 09:38:53 -0400 Authentication-Results: smtpcorp1m.mail.yandex.net; dkim=pass header.i=@yandex-team.ru Message-ID: <552BC6E8.1040400@yandex-team.ru> Date: Mon, 13 Apr 2015 16:38:48 +0300 From: Konstantin Khlebnikov User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.6.0 MIME-Version: 1.0 To: Rob Herring CC: Grant Likely , "devicetree@vger.kernel.org" , Rob Herring , "linux-kernel@vger.kernel.org" , sparclinux@vger.kernel.org, "linux-mm@kvack.org" , linuxppc-dev Subject: Re: [PATCH] of: return NUMA_NO_NODE from fallback of_node_to_nid() References: <20150408165920.25007.6869.stgit@buzz> In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2313 Lines: 67 On 13.04.2015 16:22, Rob Herring wrote: > On Wed, Apr 8, 2015 at 11:59 AM, Konstantin Khlebnikov > wrote: >> Node 0 might be offline as well as any other numa node, >> in this case kernel cannot handle memory allocation and crashes. >> >> Signed-off-by: Konstantin Khlebnikov >> Fixes: 0c3f061c195c ("of: implement of_node_to_nid as a weak function") >> --- >> drivers/of/base.c | 2 +- >> include/linux/of.h | 5 ++++- >> 2 files changed, 5 insertions(+), 2 deletions(-) >> >> diff --git a/drivers/of/base.c b/drivers/of/base.c >> index 8f165b112e03..51f4bd16e613 100644 >> --- a/drivers/of/base.c >> +++ b/drivers/of/base.c >> @@ -89,7 +89,7 @@ EXPORT_SYMBOL(of_n_size_cells); >> #ifdef CONFIG_NUMA >> int __weak of_node_to_nid(struct device_node *np) >> { >> - return numa_node_id(); >> + return NUMA_NO_NODE; > > This is going to break any NUMA machine that enables OF and expects > the weak function to work. Why? NUMA_NO_NODE == -1 -- this's standard "no-affinity" signal. As I see powerpc/sparc versions of of_node_to_nid returns -1 if they cannot find out which node should be used. > > Rob > >> } >> #endif >> >> diff --git a/include/linux/of.h b/include/linux/of.h >> index dfde07e77a63..78a04ee85a9c 100644 >> --- a/include/linux/of.h >> +++ b/include/linux/of.h >> @@ -623,7 +623,10 @@ static inline const char *of_prop_next_string(struct property *prop, >> #if defined(CONFIG_OF) && defined(CONFIG_NUMA) >> extern int of_node_to_nid(struct device_node *np); >> #else >> -static inline int of_node_to_nid(struct device_node *device) { return 0; } >> +static inline int of_node_to_nid(struct device_node *device) >> +{ >> + return NUMA_NO_NODE; >> +} >> #endif >> >> static inline struct device_node *of_find_matching_node( >> >> -- >> To unsubscribe from this list: send the line "unsubscribe devicetree" in >> the body of a message to majordomo@vger.kernel.org >> More majordomo info at http://vger.kernel.org/majordomo-info.html -- Konstantin -- 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/