From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tejun Heo Subject: Re: Port Multiplier drives not always all found on cold plug Date: Sat, 17 May 2008 23:21:21 +0900 Message-ID: <482EE9E1.5000805@gmail.com> References: <482DB79F.2030204@rtr.ca> <482DBA62.4020209@rtr.ca> <482DBC5C.3020904@rtr.ca> <482DC41F.9080901@rtr.ca> <482DCD1F.4090503@rtr.ca> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from wf-out-1314.google.com ([209.85.200.170]:5956 "EHLO wf-out-1314.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754191AbYEQOV2 (ORCPT ); Sat, 17 May 2008 10:21:28 -0400 Received: by wf-out-1314.google.com with SMTP id 27so591413wfd.4 for ; Sat, 17 May 2008 07:21:28 -0700 (PDT) In-Reply-To: <482DCD1F.4090503@rtr.ca> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Mark Lord Cc: Jeff Garzik , Alan Cox , IDE/ATA development list Mark Lord wrote: > Mark Lord wrote: >> >>> So I guess the questions are: >>> >>> 1. Where are these unexpected interrupts coming from? > .. > > Well, I'm still not sure of the source of the interrupt, > but I did just now find an ancient bug in sata_mv, > in it's internal handling of the port interrupt mask. > > The DONE_IRQ bit gets enabled a tad early in the EH sequence, > enabling us to receive interrupts when we're not expecting them. > > Looks like that mv_unexpected_intr() function was useful after all. :) > > Patches forthcoming to clean this up, once I study things a bit more. I've been studying things for last two days and discovered a number of things. I'll soon post patch series. Thanks a lot for digging into PMP stuff. It's great to have someone else's eyes on this stuff. -- tejun