On Mon, 28 Aug 2017 10:28:53 -0400 Farhan Ali <al...@linux.vnet.ibm.com> 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...)
