Re: [Qemu-devel] [PATCH] s390-ccw: Fix alignment for CCW1

[Halil Pasic]

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?