From: Theodore Tso Subject: Re: upcoming kerneloops.org item: get_page_from_freelist Date: Thu, 25 Jun 2009 21:11:55 -0400 Message-ID: <20090626011155.GI6472@mit.edu> References: <20090624150714.c7264768.akpm@linux-foundation.org> <20090625132544.GB9995@mit.edu> <20090625193806.GA6472@mit.edu> <20090625194423.GB6472@mit.edu> <20090625203743.GD6472@mit.edu> <20090625212628.GO3385@webber.adilger.int> <20090625220504.GG6472@mit.edu> <4A43F60D.2040801@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Andreas Dilger , David Rientjes , Andrew Morton , Linus Torvalds , penberg@cs.helsinki.fi, arjan@infradead.org, linux-kernel@vger.kernel.org, cl@linux-foundation.org, npiggin@suse.de, linux-ext4@vger.kernel.org To: Eric Sandeen Return-path: Received: from thunk.org ([69.25.196.29]:44089 "EHLO thunker.thunk.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752306AbZFZBMe (ORCPT ); Thu, 25 Jun 2009 21:12:34 -0400 Content-Disposition: inline In-Reply-To: <4A43F60D.2040801@redhat.com> Sender: linux-ext4-owner@vger.kernel.org List-ID: On Thu, Jun 25, 2009 at 05:11:25PM -0500, Eric Sandeen wrote: > > ecryptfs used to do kmalloc(PAGE_CACHE_SIZE) & virt_to_page on that, and > with SLUB + slub debug, that gave back non-aligned memory, causing > eventual corruption ... Grumble. Any chance we could add an kmem_cache option which requires the memory to be aligned? Otherwise we could rewrite our own sub-page allocator in ext4 that only handled aligned filesystem block sizes (i.e., 1k, 2k, 4k, etc.) but that would be really silly and be extra code that really should be done once at core functionality. - Ted