Re: [PATCH v14 03/11] target/s390x/cpu topology: handle STSI(15) and build the SYSIB

[Thomas Huth]

On 10/01/2023 15.29, Thomas Huth wrote:
> On 05/01/2023 15.53, Pierre Morel wrote:
> > On interception of STSI(15.1.x) the System Information Block
> > (SYSIB) is built from the list of pre-ordered topology entries.
> >
> > Signed-off-by: Pierre Morel <pmorel@linux.ibm.com>
> > ---
...
> > +void insert_stsi_15_1_x(S390CPU *cpu, int sel2, __u64 addr, uint8_t ar)
> > +{
> > +    union {
> > +        char place_holder[S390_TOPOLOGY_SYSIB_SIZE];
> > +        SysIB_151x sysib;
> > +    } buffer QEMU_ALIGNED(8) = {};
> > +    int len;
> > +
> > +    if (!s390_has_topology() || sel2 < 2 || sel2 > 
> > SCLP_READ_SCP_INFO_MNEST) {
> > +        setcc(cpu, 3);
> > +        return;
> > +    }
> > +
> > +    len = setup_stsi(cpu, &buffer.sysib, sel2);
> > +
> > +    if (len > 4096) {
>
> Maybe use TARGET_PAGE_SIZE instead of 4096 ?
>
> > +        setcc(cpu, 3);
> > +        return;
> > +    }
> > +
> > +    buffer.sysib.length = cpu_to_be16(len);
> > +    s390_cpu_virt_mem_write(cpu, addr, ar, &buffer.sysib, len);
>
> Is this supposed to work with protected guests, too? If so, I think you 
> likely need to use s390_cpu_pv_mem_write() for protected guests?

I now saw in a later patch that the topology feature gets disabled for 
protected guests - so never mind, please ignore my question here.

 Thomas