From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeff Garzik Subject: Re: [PATCH] Don't call request_region() for 3C90x chips Date: Wed, 19 Jul 2006 13:57:37 -0400 Message-ID: <44BE7291.2080306@pobox.com> References: <200607102225.49253.sshtylyov@ru.mvista.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, Andrew Morton Return-path: Received: from srv5.dvmed.net ([207.36.208.214]:51333 "EHLO mail.dvmed.net") by vger.kernel.org with ESMTP id S932331AbWGSR5k (ORCPT ); Wed, 19 Jul 2006 13:57:40 -0400 To: Sergei Shtylylov In-Reply-To: <200607102225.49253.sshtylyov@ru.mvista.com> Sender: netdev-owner@vger.kernel.org List-Id: netdev.vger.kernel.org Sergei Shtylylov wrote: > It's generally not a good idea to call request_region() on an address returned > by pci_iomap(), even less so on a MMIO address. And there was absolutely no > point in claiming the region already claimed by the PCI core, especially with > the same PCI generic owner's name. As this is the only case of the > must_free_region flag being set, this flag may go away as well... > > Signed-off-by: Sergei Shtylyov I agree you have identified a bug, but this is not a solution. The current driver bug is that it calls request_region() potentially on an MMIO address, but the solution is _not_ to completely avoid reserving the resource. The region registered with the PCI core, but _not_ claimed by anyone. Someone still needs to either call pci_{request,release}_regions() or request_[mem_]region() to indicate that the resource is reserved. This bug you have found was probably a missed detail during the conversion to the iomap API. Jeff