From mboxrd@z Thu Jan 1 00:00:00 1970 From: Konrad Rzeszutek Wilk Subject: Re: Re: [PATCH] Two patches fixing regression introduced by 'x86-64, mm: Put early page table high' Date: Mon, 2 May 2011 15:34:36 -0400 Message-ID: <20110502193436.GA14666@dumpdata.com> References: <1304356942-17656-1-git-send-email-konrad.wilk@oracle.com> <4DBEEA69.7010000@zytor.com> <20110502180802.GA7498@dumpdata.com> <4DBEF8EC.7080301@zytor.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <4DBEF8EC.7080301@zytor.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: "H. Peter Anvin" , yinghai@kernel.org, Stefano Stabellini , Jeremy Fitzhardinge Cc: xen-devel@lists.xensource.com, linux-kernel@vger.kernel.org List-Id: xen-devel@lists.xenproject.org On Mon, May 02, 2011 at 11:33:16AM -0700, H. Peter Anvin wrote: > On 05/02/2011 11:08 AM, Konrad Rzeszutek Wilk wrote: > >> > >> My inclination would be to apply your workaround -- are there any > >> adverse effects to doing that? > > > > There is a bootup slowdown (not noticeable). That is because we call the > > 'memblock_find_range' function on every PTE table creation (only during > > bootup of course). > > > > Testing wise, on the machines on which the regression occurred, with these two > > patches the regression disappears - so that is a good sign. I am testing > > it on some more today to assure myself I am not missing anything. > > > > OK, sounds like a plan then. I like it because it doesn't affect the > native kernel. I figured :-) Moving forward I really want to get rid of this wart. Not sure if it is possible, but I was thinking it would be nice to get you, Yinghai, Jeremy, Stefano all in one place (phone or web-conference thing) to sketch out some ideas and hammer something out. What days would work best?