From: Ralf Baechle Subject: Re: ext4dev build failure on mips: "empty_zero_page" undefined Date: Tue, 13 May 2008 06:12:52 +0100 Message-ID: <20080513051252.GA20575@linux-mips.org> References: <20080512130604.GA15008@deprecation.cyrius.com> <90edad820805120654n50f7a00cm3c7b4a4f9346d5ea@mail.gmail.com> <20080512143426.GB7029@mit.edu> <90edad820805120746l61e67362vbd177d63e8b05dc8@mail.gmail.com> <20080513045028.GC22226@linux-mips.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Theodore Tso , Martin Michlmayr , linux-mips@linux-mips.org, linux-ext4@vger.kernel.org To: Dmitri Vorobiev Return-path: Received: from vigor.karmaclothing.net ([217.169.26.28]:51606 "EHLO dl5rb.ham-radio-op.net" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753487AbYEMFNV (ORCPT ); Tue, 13 May 2008 01:13:21 -0400 Content-Disposition: inline In-Reply-To: <20080513045028.GC22226@linux-mips.org> Sender: linux-ext4-owner@vger.kernel.org List-ID: On Tue, May 13, 2008 at 05:50:29AM +0100, Ralf Baechle wrote: > > Normally I push my patches via the mips tree, and now I'm Cc:ing Ralf for that. > > > > Hopefully Ralf will react quickly. :) > > I prefer to do it myself so I can apply it at the same time to the MIPS > -stable branches. > > I'm a little irriated that this thread seems to be only about > empty_zero_page but apparently not zero_page_mask? empty_zero_page is > actualy an array of pages on MIPS and ZERO_PAGE() will pick the right one > for a particular user space mapping based on the virtual address but > ZERO_PAGE() also references zero_page_mask. So I sense more brokenness > here. The ZERO_PAGE(0) call in ext4_ext_zeroout is the culprit. Using a zero argument allows the compiler to eleminate the reference to zero_page_mask. Am I reading this right that ZERO_PAGE() is being used without any mappings to userspace being involved? Ralf