Re: [Qemu-devel] [PATCH 4/9] s390x: refactor error handling for SSCH and RSCH

[Halil Pasic]

On 09/08/2017 05:41 AM, Dong Jia Shi wrote:
> Let' me summarize here, in case I misunderstand things. Now we have
> two ways to choose:
> 
> A. Kernel: no change.
>    Qemu  : handle -EFAULT as option 2 by generating a program check.
> 
> B. Kernel: return -EFAULT
>            +
>            update the IRB area in the I/O region for option 1 to present
>            a unit check SCSW (with proper sense byte ECW), and for option
>            2 to present a program check.
>    Qemu  : handle -EFAULT according to the information that the IRB area
>            provided.

This is not what I was trying to say. You got my message regarding A, but
B was supposed to be understood like this.

Keep the current handling for option 1, that is return -EFAULT. For option
2 do what the spec says, execute the program until the bad address and then
generate a program-check (SCSW) once the bad stuff has it's turn. Thus
the only change in QEMU would be handling -EFAULT with an unit check (because
now it's just option 1).

Halil