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 31338B6FBE for ; Mon, 27 Feb 2012 10:22:38 +1100 (EST) Message-ID: <1330298534.20389.53.camel@pasglop> Subject: Re: [PATCH] powerpc/prom: bump up maximum size of properties From: Benjamin Herrenschmidt To: Nishanth Aravamudan Date: Mon, 27 Feb 2012 10:22:14 +1100 In-Reply-To: <1330129422-2648-1-git-send-email-nacc@us.ibm.com> References: <1330129422-2648-1-git-send-email-nacc@us.ibm.com> Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 Cc: linuxppc-dev@lists.ozlabs.org, Anton Blanchard , Paul Mackerras , Robert Jennings List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Fri, 2012-02-24 at 16:23 -0800, Nishanth Aravamudan wrote: > On a 16TB system (using AMS/CMO), I get: > > WARNING: ignoring large property [/ibm,dynamic-reconfiguration-memory] ibm,dynamic-memory length 0x000000000017ffec > > and significantly less memory is thus shown to the partition. As far as > I can tell, the constant used is arbitrary, but bump it up to 2MB, which > covers the above property (approximately 1.5MB). > > With this patch, the kernel does see all of the system memory on the > 16TB system. Why not go all the way to either removing the limit, or setting it to something much bigger ? That's just asking to break again when we get an even bigger system. The limit was originally set because of Apple machines carrying ROM images in the device-tree, at a time where we were much more memory constrained than we are now. But even then, it never represented such a large gain and in the end, was probably not -that- useful. I'd say bump it to something really large like 16M or remove the limit alltogether. Cheers, Ben. > Signed-off-by: Nishanth Aravamudan > Cc: Anton Blanchard > Cc: Paul Mackerras > Cc: Robert Jennings > Cc: linuxppc-dev@lists.ozlabs.org > --- > arch/powerpc/kernel/prom_init.c | 2 +- > 1 files changed, 1 insertions(+), 1 deletions(-) > > diff --git a/arch/powerpc/kernel/prom_init.c b/arch/powerpc/kernel/prom_init.c > index eca626e..0bf0ccc 100644 > --- a/arch/powerpc/kernel/prom_init.c > +++ b/arch/powerpc/kernel/prom_init.c > @@ -53,7 +53,7 @@ > * ensure that we don't lose things like the interrupt-map property > * on a PCI-PCI bridge. > */ > -#define MAX_PROPERTY_LENGTH (1UL * 1024 * 1024) > +#define MAX_PROPERTY_LENGTH (2UL * 1024 * 1024) > > /* > * Eventually bump that one up