From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kyle McMartin Subject: Re: [PATCH 2/3] e1000e: Useset_memory_ro()/set_memory_rw() to protect flash memory Date: Wed, 24 Sep 2008 13:53:58 -0400 Message-ID: <20080924175358.GA2591@phobos.i.cabal.ca> References: <20080923224535.6869.76210.stgit@jtkirshe-mobile.jf.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: jeff@garzik.org, mingo@elte.hu, davem@davemloft.net, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, jesse.brandeburg@intel.com, john.ronciak@intel.com, Bruce Allan To: Jeff Kirsher Return-path: Received: from 206-248-169-182.dsl.ncf.ca ([206.248.169.182]:52383 "EHLO phobos.cabal.ca" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751899AbYIXRx7 (ORCPT ); Wed, 24 Sep 2008 13:53:59 -0400 Content-Disposition: inline In-Reply-To: <20080923224535.6869.76210.stgit@jtkirshe-mobile.jf.intel.com> Sender: netdev-owner@vger.kernel.org List-ID: On Tue, Sep 23, 2008 at 03:45:54PM -0700, Jeff Kirsher wrote: > +#ifdef _ASM_X86_CACHEFLUSH_H > + set_memory_rw((unsigned long)hw->flash_address, > + hw->flash_len >> PAGE_SHIFT); > +#endif > writew(val, hw->flash_address + reg); > +#ifdef _ASM_X86_CACHEFLUSH_H > + set_memory_ro((unsigned long)hw->flash_address, > + hw->flash_len >> PAGE_SHIFT); > +#endif > } Hi Jeff, You're making the entire read-only mapping read-write for the single writel call... why not just limit it to the page that the writel is targetting? regards, Kyle [sorry, I've only been following this at a glance, but it's somewhat important for rawhide... does someone have a way to reproduce this at whim? Has someone tried catching it using an IOMMU on one of the newer Intel boxes, if it is a DMA going awry?]