From mboxrd@z Thu Jan 1 00:00:00 1970 From: Matthew Wilcox Subject: Re: sym53c8xx parity errors on SuSE 9.1's hwscan? Date: Thu, 23 Sep 2004 03:39:14 +0100 Sender: linux-scsi-owner@vger.kernel.org Message-ID: <20040923023914.GV16153@parcelfarce.linux.theplanet.co.uk> References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from parcelfarce.linux.theplanet.co.uk ([195.92.249.252]:17108 "EHLO www.linux.org.uk") by vger.kernel.org with ESMTP id S268146AbUIWCjP (ORCPT ); Wed, 22 Sep 2004 22:39:15 -0400 Content-Disposition: inline In-Reply-To: List-Id: linux-scsi@vger.kernel.org To: Matthias Andree Cc: linux-scsi@vger.kernel.org, Matthew Wilcox On Thu, Sep 23, 2004 at 01:16:51AM +0200, Matthias Andree wrote: > SuSE Linux 9.1 (kernel 2.6.5 + SuSE patch set, but also 2.6.7 or a bit > milder in 2.6.9-rc2-mm1) uses some SuSE-specific "hwprobe" or "hwinfo" > tool to scan for hardware. Does anyone have the source? I'd be interested to see what it's up to. > I find it a bit intimidating that user-space (albeit with root > permissions) causes "SCSI" parity errors, and given the 2.6.9 logging > towards the end of the mail, I am wondering if SuSE's hwinfo stuff > triggers some race condition or manages to bypass the SCSI phase state > machine or if the probe confuses the chip. I haven't yet managed to > isolate (with strace) the cause. I have a suggestion. If the probe attempts to size the BARs of the chip, this is a destructive process that could well cause the chip to start spewing errors are require a reset to work again. > Is there a useful debug setting for sym53c8xx that could shed some light > on what the user-space has attempted that led to the SCSI parity error? The trouble is that I suspect the probe is completely bypassing the driver. It might be worth instrumenting drivers/pci/proc.c to see if it's writing to any of the BARs (particularly the second memory BAR, the one that's 8k). -- "Next the statesmen will invent cheap lies, putting the blame upon the nation that is attacked, and every man will be glad of those conscience-soothing falsities, and will diligently study them, and refuse to examine any refutations of them; and thus he will by and by convince himself that the war is just, and will thank God for the better sleep he enjoys after this process of grotesque self-deception." -- Mark Twain