On Wed, Dec 18, 2019 at 02:22:49PM +0100, Greg Kurz wrote:
> On Wed, 18 Dec 2019 10:02:08 +0530
> Bharata B Rao <bharata@linux.ibm.com> wrote:
> 
> > A pseries guest can be run as a secure guest on Ultravisor-enabled
> > POWER platforms. When such a secure guest is reset, we need to
> > release/reset a few resources both on ultravisor and hypervisor side.
> > This is achieved by invoking this new ioctl KVM_PPC_SVM_OFF from the
> > machine reset path.
> > 
> > As part of this ioctl, the secure guest is essentially transitioned
> > back to normal mode so that it can reboot like a regular guest and
> > become secure again.
> > 
> > This ioctl has no effect when invoked for a normal guest. If this ioctl
> > fails for a secure guest, the guest is terminated.
> > 
> > Signed-off-by: Bharata B Rao <bharata@linux.ibm.com>
> > ---
> >  hw/ppc/spapr.c       |  1 +
> >  target/ppc/kvm.c     | 15 +++++++++++++++
> >  target/ppc/kvm_ppc.h |  6 ++++++
> >  3 files changed, 22 insertions(+)
> > 
> > diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
> > index f11422fc41..e62c89b3dd 100644
> > --- a/hw/ppc/spapr.c
> > +++ b/hw/ppc/spapr.c
> > @@ -1597,6 +1597,7 @@ static void spapr_machine_reset(MachineState *machine)
> >      void *fdt;
> >      int rc;
> >  
> > +    kvmppc_svm_off(&error_fatal);
> >      spapr_caps_apply(spapr);
> >  
> >      first_ppc_cpu = POWERPC_CPU(first_cpu);
> > diff --git a/target/ppc/kvm.c b/target/ppc/kvm.c
> > index 7406d18945..ae920ec310 100644
> > --- a/target/ppc/kvm.c
> > +++ b/target/ppc/kvm.c
> > @@ -2900,3 +2900,18 @@ void kvmppc_set_reg_tb_offset(PowerPCCPU *cpu, int64_t tb_offset)
> >          kvm_set_one_reg(cs, KVM_REG_PPC_TB_OFFSET, &tb_offset);
> >      }
> >  }
> > +
> > +/*
> > + * Don't set error if KVM_PPC_SVM_OFF ioctl is invoked on kernels
> > + * that don't support this ioctl.
> > + */
> > +void kvmppc_svm_off(Error **errp)
> > +{
> > +    int rc;
> > +    KVMState *s = KVM_STATE(current_machine->accelerator);
> > +
> > +    rc = kvm_vm_ioctl(s, KVM_PPC_SVM_OFF);
> > +    if (rc && rc != -ENOTTY) {
> > +        error_setg(errp, "KVM_PPC_SVM_OFF ioctl failed");
> 
> It could have made sense to use error_setg_errno(errp, -rc, ...) here
> but never mind.

Please update for this.  Otherwise we get no indication of what the
kernel level error was in the qemu error.

> 
> Reviewed-by: Greg Kurz <groug@kaod.org>
> 
> > +    }
> > +}
> > diff --git a/target/ppc/kvm_ppc.h b/target/ppc/kvm_ppc.h
> > index 47b08a4030..9a9bca1b72 100644
> > --- a/target/ppc/kvm_ppc.h
> > +++ b/target/ppc/kvm_ppc.h
> > @@ -37,6 +37,7 @@ int kvmppc_booke_watchdog_enable(PowerPCCPU *cpu);
> >  target_ulong kvmppc_configure_v3_mmu(PowerPCCPU *cpu,
> >                                       bool radix, bool gtse,
> >                                       uint64_t proc_tbl);
> > +void kvmppc_svm_off(Error **errp);
> >  #ifndef CONFIG_USER_ONLY
> >  bool kvmppc_spapr_use_multitce(void);
> >  int kvmppc_spapr_enable_inkernel_multitce(void);
> > @@ -201,6 +202,11 @@ static inline target_ulong kvmppc_configure_v3_mmu(PowerPCCPU *cpu,
> >      return 0;
> >  }
> >  
> > +static inline void kvmppc_svm_off(Error **errp)
> > +{
> > +    return;
> > +}
> > +
> >  static inline void kvmppc_set_reg_ppc_online(PowerPCCPU *cpu,
> >                                               unsigned int online)
> >  {
> 

-- 
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				| _way_ _around_!
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