From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail143.messagelabs.com (mail143.messagelabs.com [216.82.254.35]) by kanga.kvack.org (Postfix) with ESMTP id 6438D6B0044 for ; Tue, 3 Nov 2009 22:45:17 -0500 (EST) Date: Wed, 4 Nov 2009 14:22:42 +1100 From: David Gibson Subject: Re: Filtering bits in set_pte_at() Message-ID: <20091104032242.GC27772@yookeroo.seuss> References: <1256957081.6372.344.camel@pasglop> <1257200367.7907.50.camel@pasglop> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1257200367.7907.50.camel@pasglop> Sender: owner-linux-mm@kvack.org To: Benjamin Herrenschmidt Cc: Hugh Dickins , "linux-mm@kvack.org" , linuxppc-dev@lists.ozlabs.org, "linux-kernel@vger.kernel.org" List-ID: On Tue, Nov 03, 2009 at 09:19:27AM +1100, Benjamin Herrenschmidt wrote: > On Mon, 2009-11-02 at 13:27 +0000, Hugh Dickins wrote: > > On Sat, 31 Oct 2009, Benjamin Herrenschmidt wrote: > > > > > Hi folks ! > > > > > > So I have a little problem on powerpc ... :-) > > > > Thanks a lot for running this by us. > > Heh, I though you may have been bored :-) > > > I've not looked to see if there are more such issues in arch/powerpc > > itself, but those instances you mention are the only ones I managed > > to find: uses of update_mmu_cache() and that hugetlb_cow() one. > > Right, that's all I spotted so far > > > The hugetlb_cow() one involves not set_pte_at() but set_huge_pte_at(), > > so you'd want to change that too? And presumably set_pte_at_notify()? > > It all seems a lot of tedium, when so very few places are interested > > in the pte after they've set it. > > We need to change set_huge_pte_at() too. Currently, David fixed the > problem in a local tree by making hugetlb_cow() re-read the PTE . Well, actually I have another cleanup patch in the queue which makes set_huge_pte_at() equal to set_pte_at() on powerpc, and I was using that on the tree where this problem became apparent. -- David Gibson | I'll have my music baroque, and my code david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_ | _way_ _around_! http://www.ozlabs.org/~dgibson -- 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