From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx160.postini.com [74.125.245.160]) by kanga.kvack.org (Postfix) with SMTP id D5CDB6B0031 for ; Thu, 25 Jul 2013 17:38:27 -0400 (EDT) Received: by mail-ee0-f45.google.com with SMTP id b15so1191032eek.32 for ; Thu, 25 Jul 2013 14:38:26 -0700 (PDT) Date: Thu, 25 Jul 2013 23:38:22 +0200 From: Ingo Molnar Subject: Re: [PATCH v2] mm/hotplug, x86: Disable ARCH_MEMORY_PROBE by default Message-ID: <20130725213822.GG18254@gmail.com> References: <1374256068-26016-1-git-send-email-toshi.kani@hp.com> <20130722083721.GC25976@gmail.com> <1374513120.16322.21.camel@misato.fc.hp.com> <20130723080101.GB15255@gmail.com> <1374612301.16322.136.camel@misato.fc.hp.com> <20130724042041.GA8504@gmail.com> <1374685121.16322.218.camel@misato.fc.hp.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1374685121.16322.218.camel@misato.fc.hp.com> Sender: owner-linux-mm@kvack.org List-ID: To: Toshi Kani Cc: akpm@linux-foundation.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, x86@kernel.org, dave@sr71.net, kosaki.motohiro@gmail.com, isimatu.yasuaki@jp.fujitsu.com, tangchen@cn.fujitsu.com, vasilis.liaskovitis@profitbricks.com * Toshi Kani wrote: > > You claimed that the only purpose of this on x86 was > > that testing was done on non-hotplug systems, using > > this interface. Non-hotplug systems have e820 maps. > > Right. Sorry, I first thought that the interface needed > to work as defined, i.e. detect a new memory. But for > the test purpose on non-hotplug systems, that is not > necessary. So, I agree that we can check e820. > > I summarized two options in the email below. > https://lkml.org/lkml/2013/7/23/602 > > Option 1) adds a check with e820. Option 2) deprecates > the interface by removing the config option from x86 > Kconfig. I was thinking that we could evaluate two > options after this patch gets in. Does it make sense? Yeah. That having said, if the e820 check is too difficult to pull off straight away, I also don't mind keeping it as-is if it's useful for testing. Just make sure you document it as "you need to be careful with this" (beyond it being a root-only interface to begin with). Thanks, Ingo -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org