From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mark Lord Subject: Re: Problem with ata layer in 2.6.24 Date: Tue, 29 Jan 2008 13:32:09 -0500 Message-ID: <479F7129.8010406@rtr.ca> References: <200801272122.21823.gene.heskett@gmail.com> <1201539043.31293.7.camel@zem> <1201540830.6526.19.camel@localhost> <200801281230.32910.gene.heskett@gmail.com> <479E1D9E.3000900@bobjweil.com> <20080129121201.2f727f5f@core> <479F5D29.1020705@bobjweil.com> <479F6C6B.7090505@rtr.ca> <479F7049.3080904@bobjweil.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from rtr.ca ([76.10.145.34]:1328 "EHLO mail.rtr.ca" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752205AbYA2ScK (ORCPT ); Tue, 29 Jan 2008 13:32:10 -0500 In-Reply-To: <479F7049.3080904@bobjweil.com> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: rgheck Cc: Alan Cox , Daniel Barkalow , Gene Heskett , Zan Lynx , Calvin Walton , Linux Kernel Mailing List , Linux ide Mailing list rgheck wrote: > Mark Lord wrote: >> rgheck wrote: >>> Alan Cox wrote: >>>>> not one problem but lots---is sufficiently widespread that a Mini >>>>> HOWTO, say, would be really welcome and, I'm guessing, widely used. >>>>> >>>> >>>> We don't see very many libata problems at the distro level and they for >>>> the most part boil down to >>>> >>>> - sata_nv with >4GB of RAM, knowing being worked on, no old IDE driver >>>> anyway >>>> >>> Is this >4GB or >=4GB? I've seen contradictory reports, and I've got >>> 4GB. >> .. >> >> For all practical purposes, most memory over 3GB (or sometimes even 2GB) >> on a 32-bit x86 system is treated as >4GB by the motherboard. >> >> Because it's not the amount of *memory* that matters so much, >> but rather the amount of *used address space*. Video cards, >> PCI devices, other motherboard resources etc.. can all subtract >> from the available address space, leaving much less than 4GB >> for your RAM. > > Right. So it looks like I do have this issue, though I haven't seen any > actual problems on 24. Is there a known workaround? .. For now, the workaround is to not enable the RAM above 4GB. Your kernel .config file should therefore have these two lines: CONFIG_HIGHMEM4G=y # CONFIG_HIGHMEM64G is not set Later, once the issue is fixed at the driver level (soon), you can get your high memory back again by enabling CONFIG_HIGHMEM64G, though this will cost a few percent of performance in the extra page table overhead it creates. Cheers