Re: [PATCH 09/15] s390x: protvirt: SCLP interpretation

[Pierre Morel]

On 2019-11-21 15:24, Janosch Frank wrote:
> On 11/21/19 3:11 PM, Cornelia Huck wrote:
> > On Wed, 20 Nov 2019 06:43:28 -0500
> > Janosch Frank <address@hidden> wrote:
> >
> > > SCLP for a protected guest is done over the SIDAD, so we need to use
> > > the s390_cpu_virt_mem_* functions to access the SIDAD instead of guest
> > > memory when reading/writing SCBs.
> > >
> > > To not confuse the sclp emulation, we set 0x42000 as the address, but
> > > ignore it for reading/writing the SCCB.
> > >
> > > Signed-off-by: Janosch Frank <address@hidden>
> > > ---
> > >   hw/s390x/sclp.c         | 16 ++++++++++++++++
> > >   include/hw/s390x/sclp.h |  2 ++
> > >   target/s390x/kvm.c      |  8 +++++++-
> > >   3 files changed, 25 insertions(+), 1 deletion(-)
> > >
> > > diff --git a/hw/s390x/sclp.c b/hw/s390x/sclp.c
> > > index f57ce7b739..00d08adc7f 100644
> > > --- a/hw/s390x/sclp.c
> > > +++ b/hw/s390x/sclp.c
> > > @@ -193,6 +193,22 @@ static void sclp_execute(SCLPDevice *sclp, SCCB *sccb, 
> > > uint32_t code)
> > >       }
> > >   }
> > >   
> > > +int sclp_service_call_protected(CPUS390XState *env, uint64_t sccb,
> > > +                                uint32_t code)
> > > +{
> > > +    SCLPDevice *sclp = get_sclp_device();
> > > +    SCLPDeviceClass *sclp_c = SCLP_GET_CLASS(sclp);
> > > +    SCCB work_sccb;
> > > +    hwaddr sccb_len = sizeof(SCCB);
> > > +
> > > +    s390_cpu_virt_mem_read(env_archcpu(env), 0, 0, &work_sccb, sccb_len);
> > > +    sclp_c->execute(sclp, &work_sccb, code);
> > > +    s390_cpu_virt_mem_write(env_archcpu(env), 0, 0, &work_sccb,
> > > +                            be16_to_cpu(work_sccb.h.length));
> > > +    sclp_c->service_interrupt(sclp, sccb);
> > > +    return 0;
> > > +}
> > > +
> > >   int sclp_service_call(CPUS390XState *env, uint64_t sccb, uint32_t code)
> > >   {
> > >       SCLPDevice *sclp = get_sclp_device();
> > > diff --git a/include/hw/s390x/sclp.h b/include/hw/s390x/sclp.h
> > > index c54413b78c..c0a3faa37d 100644
> > > --- a/include/hw/s390x/sclp.h
> > > +++ b/include/hw/s390x/sclp.h
> > > @@ -217,5 +217,7 @@ void s390_sclp_init(void);
> > >   void sclp_service_interrupt(uint32_t sccb);
> > >   void raise_irq_cpu_hotplug(void);
> > >   int sclp_service_call(CPUS390XState *env, uint64_t sccb, uint32_t code);
> > > +int sclp_service_call_protected(CPUS390XState *env, uint64_t sccb,
> > > +                                uint32_t code);
> > >   
> > >   #endif
> > > diff --git a/target/s390x/kvm.c b/target/s390x/kvm.c
> > > index 58251c0229..0f2458b553 100644
> > > --- a/target/s390x/kvm.c
> > > +++ b/target/s390x/kvm.c
> > > @@ -1172,7 +1172,13 @@ static int kvm_sclp_service_call(S390CPU *cpu, struct 
> > > kvm_run *run,
> > >       sccb = env->regs[ipbh0 & 0xf];
> > >       code = env->regs[(ipbh0 & 0xf0) >> 4];
> > >   
> > > -    r = sclp_service_call(env, sccb, code);
> > > +    if (run->s390_sieic.icptcode == ICPT_PV_INSTR ||
> > > +        run->s390_sieic.icptcode == ICPT_PV_INSTR_NOT) {
> > > +        r = sclp_service_call_protected(env, 0x42000, code);
> > I fear that confuses the reader instead of the emulation :)
> >
> > Especially as you end up passing that value to
> > sclp_c->service_interrupt()...
> Pierre has some more opinions on that, so I'll let him present his
> planned changes to this patch :)


Hum, sorry but I can not present any thing at the moment.
I will study the problem, it will take some time.


> > > +    } else {
> > > +        r = sclp_service_call(env, sccb, code);
> > > +    }
> > > +
> > >       if (r < 0) {
> > >           kvm_s390_program_interrupt(cpu, -r);
> > >       } else {
--
Pierre Morel
IBM Lab Boeblingen