From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx189.postini.com [74.125.245.189]) by kanga.kvack.org (Postfix) with SMTP id B78ED6B004D for ; Thu, 19 Jul 2012 19:50:56 -0400 (EDT) Date: Fri, 20 Jul 2012 08:50:57 +0900 From: Minchan Kim Subject: Re: + memory-hotplug-fix-kswapd-looping-forever-problem-fix-fix.patch added to -mm tree Message-ID: <20120719235057.GA21012@bbox> References: <20120717233115.A8E411E005C@wpzn4.hot.corp.google.com> <20120718012200.GA27770@bbox> <20120718143810.b15564b3.akpm@linux-foundation.org> <20120719001002.GA6579@bbox> <20120719002102.GN24336@google.com> <20120719004845.GA7346@bbox> <20120719165750.GP24336@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20120719165750.GP24336@google.com> Sender: owner-linux-mm@kvack.org List-ID: To: Tejun Heo Cc: Andrew Morton , Ralf Baechle , aaditya.kumar.30@gmail.com, kamezawa.hiroyu@jp.fujitsu.com, linux-mm@kvack.org, Johannes Weiner , Yinghai Lu On Thu, Jul 19, 2012 at 09:57:50AM -0700, Tejun Heo wrote: > Hello, > > On Thu, Jul 19, 2012 at 09:48:45AM +0900, Minchan Kim wrote: > > > Maybe trigger warning if some fields which have to be zero aren't? > > > > It's not good because this causes adding new WARNING in that part > > whenever we add new field in pgdat. It nullify this patch's goal. > > Maybe just do that on some fields? The goal is catching unlikely case > where archs leave the struct with garbage data. I don't think full > coverage is an absolute requirement. Or reorganize the fields such IIUC your previous reply, archs can use any fields during boot. If so, we need full coverage for catching it. > that fields unused by boot code is collected at the top so that it can > be memset after certain offset? If the fields touched by boot are limited, it's good idea. Let me ask a question. What fields are used by boot code before calling free_area_init_node (excpet struct bootmem_data *bdata)? > > But, really, given how the structure is used, I think we're better off > just making sure all archs clear them and maybe have a sanity check or > two just in case. It's not like breakage on that front is gonna be > subtle. Of course, it seems all archs seems to zero-out already as I mentioned (Not sure, MIPS) but Andrew doesn't want it. Andrew? > > Thanks. > > -- > tejun > > -- > 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 -- Kind regards, Minchan Kim -- 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