From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752414AbbHPOeV (ORCPT ); Sun, 16 Aug 2015 10:34:21 -0400 Received: from mx02.unibo.it ([137.204.24.59]:43403 "EHLO mx02.unibo.it" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751361AbbHPOeU (ORCPT ); Sun, 16 Aug 2015 10:34:20 -0400 X-Greylist: delayed 901 seconds by postgrey-1.27 at vger.kernel.org; Sun, 16 Aug 2015 10:34:20 EDT X-AuditID: 89cc183b-f79866d000004835-40-55d09bdc8567 Message-ID: <55D09BD8.4090601@unibo.it> Date: Sun, 16 Aug 2015 16:19:04 +0200 From: Sergio Callegari User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.8.0 MIME-Version: 1.0 To: Subject: Regression: commit 045065d breaks kernel on machine with atapi floppy: high IOWAIT, hung processes (bisected) Content-Type: text/plain; charset="utf-8"; format=flowed Content-Transfer-Encoding: 7bit X-Originating-IP: [5.170.91.192] X-ClientProxiedBy: E13-MBX1-CS.personale.dir.unibo.it (10.12.1.71) To E13-MBX2-CS.personale.dir.unibo.it (10.12.1.72) X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFmpileLIzCtJLcpLzFFi42Lh4mH00L0z+0KowadjShaXd81hc2D0+LxJ LoAxitsmKbGkLDgzPU/fLoE74//0lewFj3krjvU+YWpg7OTuYuTkkBAwkfj9+AcrhC0mceHe erYuRi4OIYFljBI75l5lh3C2Mkq8+/WIGaSKV0Bd4vK7L0wgNouAqsTec1vAutkEjCSOftvG BmKLCoRJXDmzEapeUOLkzCcsILaIgJLE92vdjCC2sECFxKrzf8B6mQUsJGbOP88IYctLbH87 B6xXSEBNYkr/XhaI6xQkzrSsh7LLJda92cc+gVFgFpIVs5CMmoVk1AJG5lWMYsW56brFyYl5 RnrJxXqleZlJ+Xo5+cmbGIFh2HlGwnoH44wLbocYBTgYlXh4JQ6dDxViTSwrrsw9xCjJwaQk yvsgCijEl5SfUpmRWJwRX1Sak1p8iFGCg1lJhFen90KoEG9KYmVValE+TEqag0VJnJeRgYFB SCA9sSQ1OzW1ILUIJivDwaEkwas3C6hRsCg1PbUiLTOnBCHNxMEJMpxLSqQ4NS8ltSixtCQj HhSb8cXA6ARJ8QDtDQZp5y0uSMwFikK0nmLU5diy4MZaJiGWvPy8VClxXhuQIgGQoozSPLgV oKTDuir6wCtGcaCPhXnLQap4gAkLbtIroCVMQEvsZpwFWVKSiJCSamDcN2dbF0sWp5O58GlX 8Zfhrf6rz3v67L8q+eLWvhOLAj3CA1t/NWkc23dDme+T0c3Ad/oCGjOfyBQWKvsJaZ1Qv5D2 /EWUe+epp7NF2/vvBc9cxbvQ8snEU4UJn1++cRLZOX/GZ+HgSYfUfk43jIicb1fzzib/uBtb b0C6MXPzQ7sK8+0FtZ1KLMUZiYZazEXFiQB8/bqZFQMAAA== Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, please keep me in CC in answers. I'd like to report that after commit [045065d8a300a37218c548e9aa7becd581c6a0e8] [SCSI] fix qemu boot hang problem the kernel is not usable on a machine with an IOMEGA Zip 100 ATAPI drive as in: Model=IOMEGA ZIP 100 ATAPI Floppy, FwRev=12.A, SerialNo= Config={ SpinMotCtl Removeable nonMagnetic } RawCHS=0/0/0, TrkSize=0, SectSize=0, ECCbytes=0 BuffType=unknown, BuffSize=unknown, MaxMultSect=0 (maybe): CurCHS=0/0/0, CurSects=0, LBA=yes, LBAsects=0 IORDY=on/off, tPIO={min:500,w/IORDY:180} PIO modes: pio0 pio1 pio2 pio3 AdvancedPM=no Symptoms include: - Extremely high IOWAIT in absence of load - Kernel reporting hung processes - Commands like blkid hanging - Inability of the machine to shutdown Symptoms do not appear immediately, but after some time (anywhere between a few minutes and /many hours/ after boot). First symptom is IOWAIT suddendly jumping high. Due to the delay in which symptoms manifest, bisecting has been quite painful, but I am now rather sure that the first bad commit is the one above. Other pieces of hardware configuration include: - ASRock N68S motherboard with AMD Phenom(tm) II X4 920 Processor and NVIDIA MCP61 SATA/IDE Chipset - IDE drive connected as slave on ide interface where master is HL-DT-ST DVD-RAM GH22NP20 CDROM/DVD writer Issue is weird because the commit seems to merely fix a trivial error in logic condition - if (atomic_read(&sdev->device_busy) && !scsi_device_blocked(sdev)) + if (!atomic_read(&sdev->device_busy) && !scsi_device_blocked(sdev)) blk_delay_queue(q, SCSI_QUEUE_DELAY); Hence, the commit may just end up making visible some other issue. Best, Sergio