Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757296Ab0FDDmK (ORCPT ); Thu, 3 Jun 2010 23:42:10 -0400 Received: from mail-iw0-f174.google.com ([209.85.214.174]:54222 "EHLO mail-iw0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756997Ab0FDDmG (ORCPT ); Thu, 3 Jun 2010 23:42:06 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:user-agent:mime-version:to:cc:subject :references:in-reply-to:content-type:content-transfer-encoding; b=JvEbmaaGfiC3UQFQODdwXmjwBnVtlUtdVbR65KBk3o38hNdJSzAwj0/z5ZinP/Ycx3 7pn5e5IkZQn8JBE/vQggvcsN2OHmgEV3zL225uydYW3J6oowP+S+UvjE7+cE0/68JCU1 e+FbKzs2bHJjwdiAaryCcChqEEe45vUIYPk5U= Message-ID: <4C08760B.8050002@gmail.com> Date: Thu, 03 Jun 2010 21:42:03 -0600 From: Robert Hancock User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.9) Gecko/20100430 Fedora/3.0.4-3.fc13 Thunderbird/3.0.4 MIME-Version: 1.0 To: Marc Dionne CC: Matthew Garrett , Linux Kernel Mailing List , linux-ide@vger.kernel.org, garzik@redhat.com Subject: Re: Hang during boot, bisected to commit 96d60303fd References: <20100603020006.GB19123@srcf.ucam.org> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2314 Lines: 48 On 06/03/2010 07:21 PM, Marc Dionne wrote: > On Wed, Jun 2, 2010 at 10:00 PM, Matthew Garrett wrote: >> On Wed, Jun 02, 2010 at 09:49:27PM -0400, Marc Dionne wrote: >>> Since somewhere early in the 2.6.35 merge window I've been seeing a hang >>> during boot. The hang last roughly 30 seconds and is followed by this: >>> >>> ata4.00: exception Emask 0x0 SAct 0x1 SErr 0x0 action 0x6 frozen >>> ata4.00: failed command: READ FPDMA QUEUED >>> ata4.00: cmd 60/08:00:00:00:00/00:00:00:00:00/40 tag 0 ncq 4096 in >>> res 40/00:00:00:00:00/00:00:00:00:00/00 Emask 0x4 (timeout) >>> ata4.00: status: { DRDY } >>> ata4: hard resetting link >>> ahci_is_device_present: status is: 80 >>> ahci_is_device_present: status(2) is: 3 >>> ata4: SATA link up 3.0 Gbps (SStatus 123 SControl 300) >>> ata4.00: configured for UDMA/133 >>> ata4.00: device reported invalid CHS sector 0 >>> ata4: EH complete >>> >>> The system works normally once booted. I had some time to do a bisect >>> today and it cleanly ended up pointing to this commit: >>> 96d60303fd: ahci: Turn off DMA engines when there's no device attached >>> >>> Reverting the commit makes the system boot cleanly as before. System has >>> an Intel ICH10 based board, in AHCI mode, disk is an Intel X25M SSD. >> >> Hm, interesting. Jeff, any immediate ideas? I don't see this behaviour >> on my ICH10. Is there actually a device on ata4? >> >> -- >> Matthew Garrett | mjg59@srcf.ucam.org > > If it's helpful, attached are the dmesg output following a normal boot > and one with the hang. > > The only difference in the kernel used for those two boots is that the > return statement in ahci_start_engine following the call to > ahci_is_device_present is commented out for the normal boot case. > When the return statement is active, the 30 second hang occurs. Can you try and put a printk in where it's returning out of the ahci_start_engine method? I wonder if that's getting triggered somewhere unexpected.. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/