From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tejun Heo Subject: Re: [PATCH] libata: disable_irq() during polling IDENTIFY (take 2) Date: Tue, 08 May 2007 14:01:40 +0200 Message-ID: <464066A4.1010008@gmail.com> References: <463EAB4D.3000309@tw.ibm.com> <463ED8B9.4060501@gmail.com> <463F0B25.40103@tw.ibm.com> <463F0DAD.5060307@gmail.com> <463F1374.1010100@tw.ibm.com> <463F1509.30100@gmail.com> <46405F50.5090901@tw.ibm.com> <20070508130025.7693980c@the-village.bc.nu> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: Received: from nz-out-0506.google.com ([64.233.162.236]:30316 "EHLO nz-out-0506.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S967423AbXEHMBx (ORCPT ); Tue, 8 May 2007 08:01:53 -0400 Received: by nz-out-0506.google.com with SMTP id o1so1935643nzf for ; Tue, 08 May 2007 05:01:53 -0700 (PDT) In-Reply-To: <20070508130025.7693980c@the-village.bc.nu> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Alan Cox Cc: albertl@mail.com, albertcc@tw.ibm.com, Jeff Garzik , Linux IDE , Doug Maxey , bzolnier@gmail.com, Mark Lord Alan Cox wrote: > On Tue, 08 May 2007 19:30:24 +0800 > Albert Lee wrote: > >> Problem: >> Kernel got "irq 5: nobody cared" when using >> libata + polling IDENTIFY + Promise 20275 adapter + Benq DW1620 drive. >> >> Detail message available in bug 8441 (http://bugzilla.kernel.org/show_bug.cgi?id=8441). >> >> Cause: >> The Benq DW1620 drive raises INTRQ during polling IDENTIFY PACKET DEVICE, >> even if nIEN = 1. >> >> Proposed fix: >> Ack the possibly unexpected irq in ata_interrupt(). >> >> Signed-off-by: Albert Lee > > NAK > > We can't do this. A PIO data transfer could take far far too long to be > under IRQ block (its already a problem on a big 32bit box when we bounce > buffer it sometimes). Oh well, that's how we do PIO data transfer when not polling anyway. We kick HSM directly from the interrupt handler and do PIO inside the interrupt handler. The change made here is to make polling PIO act the same way. -- tejun