From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tejun Heo Subject: Re: ahci port hangs while hard resetting link Date: Mon, 23 Aug 2010 11:31:32 +0200 Message-ID: <4C723FF4.1020208@kernel.org> References: <201008230010.48355.anssi.hannula@iki.fi> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: Received: from hera.kernel.org ([140.211.167.34]:53202 "EHLO hera.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753671Ab0HWJgV (ORCPT ); Mon, 23 Aug 2010 05:36:21 -0400 In-Reply-To: <201008230010.48355.anssi.hannula@iki.fi> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Anssi Hannula Cc: linux-ide@vger.kernel.org Hello, On 08/22/2010 11:10 PM, Anssi Hannula wrote: > 22:52:18 : ata6: exception Emask 0x10 SAct 0x0 SErr 0x4050002 action 0xe > frozen > 22:52:18 : ata6: irq_stat 0x00400040, connection status changed > 22:52:18 : ata6: SError: { RecovComm PHYRdyChg CommWake DevExch } > 22:52:18 : ata6: hard resetting link > 22:52:28 : ata6: softreset failed (device not ready) > 22:52:28 : ata6: hard resetting link > 22:52:38 : ata6: softreset failed (device not ready) > 22:52:38 : ata6: hard resetting link > 22:52:49 : ata6: link is slow to respond, please be patient (ready=0) > 22:53:13 : ata6: softreset failed (device not ready) > 22:53:13 : ata6: limiting SATA link speed to 1.5 Gbps > 22:53:13 : ata6: hard resetting link > ===================== > I disconnect the drive for a few moments, but nothing is output by kernel. > I reconnect it again, but again, nothing is output by the kernel. > I run: echo "- - -" > > /sys/devices/pci0000:00/0000:00:1f.2/host5/scsi_host/host5/scan > However, it appeared stuck and still no messages in the kernel log, so > I disconnected the device again. Still nothing is output, and the > following messages started to be output, indicating that the process > had become stuck: Looks like EH got stuck somehow. Maybe the timeout calculation is wrong? Can you please trigger sysrq-t while the system is stuck and post the result? Thanks. -- tejun