From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail6.bemta7.messagelabs.com (mail6.bemta7.messagelabs.com [216.82.255.55]) by kanga.kvack.org (Postfix) with ESMTP id C58CE6B00CA for ; Wed, 23 Nov 2011 08:23:30 -0500 (EST) Date: Wed, 23 Nov 2011 14:25:56 +0100 From: Stanislaw Gruszka Subject: Re: [PATCH v2 1/3] mm: more intensive memory corruption debug Message-ID: <20111123132555.GB7943@redhat.com> References: <1321633507-13614-1-git-send-email-sgruszka@redhat.com> <20111122135608.42686f14.akpm@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20111122135608.42686f14.akpm@linux-foundation.org> Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Mel Gorman , Andrea Arcangeli , "Rafael J. Wysocki" , Christoph Lameter On Tue, Nov 22, 2011 at 01:56:08PM -0800, Andrew Morton wrote: > On Fri, 18 Nov 2011 17:25:05 +0100 > Stanislaw Gruszka wrote: > I added this: > > The default value of debug_guardpage_minorder is zero: no change > from current behaviour. > > correct? Yes, > > +static inline void clear_page_guard_flg(struct page *page) > > +{ > > + __clear_bit(PAGE_DEBUG_FLAG_GUARD, &page->debug_flags); > > +} > > Why is it safe to use the non-atomic bitops here. Clearing/setting flag is done only in __free_one_page()/expand(), so operations are protected by zone->lock. > Please verify that CONFIG_WANT_PAGE_DEBUG_FLAGS is always reliably > enabled when this feature is turned on. Change in mm/Kconfig.debug assures that CONFIG_WANT_PAGE_DEBUG_FLAGS is set whenever CONFIG_DEBUG_PAGEALLOC is. > Some changes I made - please review. Look good, thanks Andrew! Stanislaw -- 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