From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from gate.crashing.org (gate.crashing.org [63.228.1.57]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id 8E7B8B7088 for ; Wed, 19 Jan 2011 17:06:28 +1100 (EST) Subject: Re: 2.6.37-git17 virtual IO boot failure From: Benjamin Herrenschmidt To: Nishanth Aravamudan In-Reply-To: <20110119004824.GA20441@us.ibm.com> References: <20110118123152.50f75a72@kryten> <20110118224718.GA19039@us.ibm.com> <20110119004824.GA20441@us.ibm.com> Content-Type: text/plain; charset="UTF-8" Date: Wed, 19 Jan 2011 17:06:18 +1100 Message-ID: <1295417178.2148.131.camel@pasglop> Mime-Version: 1.0 Cc: linuxppc-dev@ozlabs.org, sonnyrao@us.ibm.com, Anton Blanchard , miltonm@bga.com List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Tue, 2011-01-18 at 16:48 -0800, Nishanth Aravamudan wrote: > > Ben, if you're ok with waiting to see if Milton or Sonny have any > ideas, > I'd like to hold off on asking for a revert. In the case they do, I'll > be able to test and send out any proposed fix rapidly. I don't believe this specific error is causing the lockup, I think we only hit a spurrious message on devices that don't have DMA capabilities in the first place. (But I may be wrong, I'll wait for you guys to dig more or I'll have a look myself tomorrow if I manage to get out of meetings). So there's another problem with SCSI tho it -could- also be a DMA issue, hard to tell at this point. BTW. I'm not too happy with those defaults set to 64-bit. Probably not an issue until your other patches go in, but some devices like veth cannot do 64-bit DMA. I think we should default to 32-bit in the VIO base code and explicitely enable 64-bit DMA from drivers that support it (in theory vscsi but I haven't verified the implementation). Cheers, Ben.