From mboxrd@z Thu Jan 1 00:00:00 1970 From: Robert Hancock Subject: Re: MSI broken in libata? Date: Sun, 10 Jan 2010 19:39:38 -0600 Message-ID: <4B4A815A.60503@gmail.com> References: <64bb37e0912250122n4e0e1842q88c0dad7e99ec6a7@mail.gmail.com> <4B484829.6060405@kernel.org> <64bb37e1001092033r1f0b4defw46c1a07101bb2d1b@mail.gmail.com> <4B4A7BC7.6060106@kernel.org> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from mail-yx0-f187.google.com ([209.85.210.187]:35408 "EHLO mail-yx0-f187.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750786Ab0AKBjl (ORCPT ); Sun, 10 Jan 2010 20:39:41 -0500 In-Reply-To: <4B4A7BC7.6060106@kernel.org> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Tejun Heo Cc: Torsten Kaiser , linux-kernel@vger.kernel.org, Jeff Garzik , linux-ide@vger.kernel.org On 01/10/2010 07:15 PM, Tejun Heo wrote: > On 01/10/2010 01:33 PM, Torsten Kaiser wrote: >> I did try the patch from Robert Hancock in >> http://lkml.org/lkml/2010/1/6/417 ,but without success. >> >> if you need any more information, or have something for me to try, >> please just ask. I did look at the code and the documentation about >> enabling MSI, but did not see anything (obvious) wrong, so I don't >> know what to try next. > > Can you please try the attached patch? > > Thanks. > It'd be interesting to see if it makes a difference, but I don't think the patch is quite right. According to the datasheet, doing the MSI ack while the interrupt source is still pending will cause a new MSI to be sent, so if you do it before handling the interrupt you'll generate a spurious interrupt after every real one. Though, apparently my patch that did the MSI ack after the handling didn't help, so either that's wrong or the problem is unrelated. (I tend to suspect the latter, given that sata_nv is also failing in the same way.)