From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752726AbcFIRCF (ORCPT ); Thu, 9 Jun 2016 13:02:05 -0400 Received: from mail.kernel.org ([198.145.29.136]:48986 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751035AbcFIRCD (ORCPT ); Thu, 9 Jun 2016 13:02:03 -0400 Date: Thu, 9 Jun 2016 12:01:56 -0500 From: Bjorn Helgaas To: Arnd Bergmann Cc: Krzysztof =?utf-8?Q?Ha=C5=82asa?= , Bjorn Helgaas , linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] Revert "ARM: cns3xxx: pci: avoid potential stack overflow" Message-ID: <20160609170156.GB1109@localhost> References: <20160531215802.30590.97398.stgit@bhelgaas-glaptop2.roam.corp.google.com> <11128570.JeBAgI5zQr@wuerfel> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <11128570.JeBAgI5zQr@wuerfel> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jun 01, 2016 at 11:09:47PM +0200, Arnd Bergmann wrote: > On Wednesday, June 1, 2016 1:08:59 PM CEST Krzysztof Hałasa wrote: > > Bjorn Helgaas writes: > > > > > This reverts commit 498a92d42596a7a32c042319eb62a4c3d8081cf1. > > > > > > Krzysztof reported that this change broke Cavium CNS3xxx, ARMv6 (Laguna > > > GW-2388) because the MRRS setting is never written to the hardware. > > > > > > Signed-off-by: Bjorn Helgaas > > > CC: Arnd Bergmann > > > CC: Krzysztof Hałasa > > > --- > > > arch/arm/mach-cns3xxx/pcie.c | 71 ++++++++++++++++++++++++------------------ > > > 1 file changed, 41 insertions(+), 30 deletions(-) > > > > This, applied to v4.7-rc1, fixes the problem on my Laguna boards. > > > > Tested-by: Krzysztof Hałasa > > > > And as well > > > > Acked-by: Krzysztof Hałasa > > Thank! > > Obviously, I'd rather not bring back the gcc warning or the potential > stack overflow (however unlikely). > > What exactly is the problem we are seeing, and is there a way to fix > it on top of my patch? Are we perhaps just missing a call to > pcie_bus_configure_settings()? > > Note that cns3xxx is in a bit of an odd state, as only half of the > platform code is even present in the kernel, and there is no effort > to change that. As far as I know, the board that this was tested on > is not present in the mainline kernel, and the board we support > is a development system that few people even own at this point. I'm sure there's a good, simple fix for this that would be better than the revert. Unfortunately I don't have time to work on it right now. I'll be on vacation for the last 2-3 weeks before v4.7 releases, so I'm scrambling to get the big chunks merged before 6/22 or so. Bjorn