From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx185.postini.com [74.125.245.185]) by kanga.kvack.org (Postfix) with SMTP id C3E166B0082 for ; Thu, 16 Feb 2012 16:42:48 -0500 (EST) Date: Thu, 16 Feb 2012 22:42:45 +0100 From: Andrea Arcangeli Subject: Re: exit_mmap() BUG_ON triggering since 3.1 Message-ID: <20120216214245.GD23585@redhat.com> References: <20120215183317.GA26977@redhat.com> <20120216070753.GA23585@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: owner-linux-mm@kvack.org List-ID: To: Hugh Dickins Cc: Dave Jones , Andrew Morton , David Rientjes , linux-kernel@vger.kernel.org, linux-mm@kvack.org, kernel-team@fedoraproject.org On Thu, Feb 16, 2012 at 01:53:04AM -0800, Hugh Dickins wrote: > Yes (and I think less troublesome than most BUGs, coming at exit > while not holding locks; though we could well make it a WARN_ON, > I don't think that existed back in the day). A WARN_ON would be fine with me, go ahead if you prefer it... only risk would be to go unnoticed or be underestimated. I am ok with the BUG_ON too (even if this time it triggered false positives... sigh). > Acked-by: Hugh Dickins Thanks for the quick review! > In looking into the bug, it had actually bothered me a little that you > were setting aside those pages, yet not counting them into nr_ptes; > though the only thing that cares is oom_kill.c, and the count of pages > in each hugepage can only dwarf the count in nr_ptes (whereas, without > hugepages, it's possible to populate very sparsely and nr_ptes become > significant). Agreed, it's not significant either ways. Running my two primary systems with this applied for half a day and no problem so far so it should be good for -mm at least. -- 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/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org