From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:37125) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dmfG3-0006No-T1 for qemu-devel@nongnu.org; Tue, 29 Aug 2017 08:04:44 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dmfFy-0007Gc-9g for qemu-devel@nongnu.org; Tue, 29 Aug 2017 08:04:39 -0400 Received: from mx1.redhat.com ([209.132.183.28]:44314) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1dmfFy-0007GK-18 for qemu-devel@nongnu.org; Tue, 29 Aug 2017 08:04:34 -0400 Date: Tue, 29 Aug 2017 14:04:29 +0200 From: Cornelia Huck Message-ID: <20170829140429.08a1731c.cohuck@redhat.com> In-Reply-To: <3421f46f-fa82-ac23-b0ac-5a2acce26d41@linux.vnet.ibm.com> References: <3ed8b810b6592daee6a775037ce21f850e40647d.1503667215.git.alifm@linux.vnet.ibm.com> <20170825160408.2775c8b5.cohuck@redhat.com> <00d41b2b-cf22-c9e2-8d9f-de947f4d3f18@linux.vnet.ibm.com> <20170828102214.7aad9112.cohuck@redhat.com> <20170828150653.7cdc8c5a.cohuck@redhat.com> <20170828160554.45855dfa.cohuck@redhat.com> <9b9880e4-71fd-4bc5-961b-ab0e2b298f03@linux.vnet.ibm.com> <3421f46f-fa82-ac23-b0ac-5a2acce26d41@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH] s390-ccw: Fix alignment for CCW1 List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Farhan Ali Cc: Halil Pasic , Christian Borntraeger , qemu-devel@nongnu.org, farman@linux.vnet.ibm.com, walling@linux.vnet.ibm.com On Mon, 28 Aug 2017 10:28:53 -0400 Farhan Ali wrote: > On 08/28/2017 10:19 AM, Halil Pasic wrote: > > > > > > On 08/28/2017 04:15 PM, Farhan Ali wrote: > >> > >> > >> On 08/28/2017 10:05 AM, Cornelia Huck wrote: > >>>>>> It's the alignment of the CCW which causes the problem. > >>>>>> > >>>>>> The exact error message when starting the guest was: > >>>>>> > >>>>>> ! No virtio device found ! > >>>>>> > >>>>>> Since it worked for SCSI and CDL, and failed for LDL disks on that particular system, we are not really sure what caused the failure. > >>>>>> Debugging it further showed the CCW for LDL disks were not aligned at double word boundary. > >>> This is really, really odd, as the low-level ccw code is the same for > >>> any disk type... > >>> > >> Exactly! > >> > >>>>>> Trying the test on a different system with LDL disks worked fine, with the aligned(8) fix. > >>>>> Do you happen to have an old s390-ccw.img laying around in the test folder? QEMU might pick up > >>>>> this one (e.g. when calling it without libvirt from the command line). > >>>>> > >>>> I explicitly mention the bios to use with '-bios' option and pick up the > >>>> latest bios. Without the aligned fix I see the error and with the fix it > >>>> works fine. > >>> Wait, so the fix fixes it? Or am I confused now? > >>> > >> > >> It fixes in my system and one other system we tried on. But fails on a system where this issue was first noticed. > > > > This is very confusing. So you have tried -bios on the system > > where the issue was first noticed and the issue still persists > > despite of the fixed bios is specified? > > > Yes. > > The system where the issue was first noticed, applying the fix for the > bios, fixes for: > > 1) CDL disks > 2) SCSI disks > > But fails for LDL disk. > > On my system and one other system, the fix works for all the disk types, > CDL, SCSI and LDL and fixes the issue. Are you using different toolchains on the failing and the working systems? Does it work when you copy the bios from a working system? (Clutching at straws here...)