From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx196.postini.com [74.125.245.196]) by kanga.kvack.org (Postfix) with SMTP id E50D66B005A for ; Tue, 8 Jan 2013 12:29:47 -0500 (EST) Date: Tue, 8 Jan 2013 19:30:58 +0200 From: "Kirill A. Shutemov" Subject: Re: oops in copy_page_rep() Message-ID: <20130108173058.GA27727@shutemov.name> References: <20130105152208.GA3386@redhat.com> <20130108163141.GA27555@shutemov.name> 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: Linus Torvalds Cc: Hillf Danton , Hugh Dickins , Dave Jones , Linux Kernel , Andrea Arcangeli , Andrew Morton , Mel Gorman , Linux-MM , Rik van Riel On Tue, Jan 08, 2013 at 08:52:14AM -0800, Linus Torvalds wrote: > On Tue, Jan 8, 2013 at 8:31 AM, Kirill A. Shutemov wrote: > >> > >> Heh. I was more thinking about why do_huge_pmd_wp_page() needs it, but > >> do_huge_pmd_numa_page() does not. > > > > It does. The check should be moved up. > > > >> Also, do we actually need it for huge_pmd_set_accessed()? The > >> *placement* of that thing confuses me. And because it confuses me, I'd > >> like to understand it. > > > > We need it for huge_pmd_set_accessed() too. > > > > Looks like a mis-merge. The original patch for huge_pmd_set_accessed() was > > correct: http://lkml.org/lkml/2012/10/25/402 > > Not a merge error: the pmd_trans_splitting() check was removed by > commit d10e63f29488 ("mm: numa: Create basic numa page hinting > infrastructure"). Check difference between patch above and merged one -- a1dd450. Merged patch is obviously broken: huge_pmd_set_accessed() can be called only if the pmd is under splitting. -- Kirill A. Shutemov -- 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