The formula used to compute the address of the HPT allocated by QEMU is
open-coded in several places. This patch moves the magic to a dedicated
helper. While here, we also patch the callers to only pass the address
to KVM if we indeed have a userland HPT (ie, KVM PR).

Signed-off-by: Greg Kurz <groug@kaod.org>
---
 hw/ppc/spapr.c          |    9 +++++++++
 hw/ppc/spapr_cpu_core.c |   12 +++++++-----
 hw/ppc/spapr_hcall.c    |   14 ++++++++------
 include/hw/ppc/spapr.h  |    1 +
 4 files changed, 25 insertions(+), 11 deletions(-)

diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
index caffa1276328..bf24c26b756d 100644
--- a/hw/ppc/spapr.c
+++ b/hw/ppc/spapr.c
@@ -1290,6 +1290,15 @@ static void spapr_store_hpte(PPCVirtualHypervisor *vhyp, hwaddr ptex,
     }
 }
 
+target_ulong spapr_get_hpt_pointer(sPAPRMachineState *spapr)
+{
+    if (!spapr->htab) {
+        return 0;
+    }
+
+    return (target_ulong)(uintptr_t)spapr->htab | (spapr->htab_shift - 18);
+}
+
 int spapr_hpt_shift_for_ramsize(uint64_t ramsize)
 {
     int shift;
diff --git a/hw/ppc/spapr_cpu_core.c b/hw/ppc/spapr_cpu_core.c
index 85037ef71e27..581eb4d92de9 100644
--- a/hw/ppc/spapr_cpu_core.c
+++ b/hw/ppc/spapr_cpu_core.c
@@ -93,11 +93,13 @@ static void spapr_cpu_reset(void *opaque)
      * HPT
      */
     if (kvm_enabled()) {
-        env->spr[SPR_SDR1] = (target_ulong)(uintptr_t)spapr->htab
-            | (spapr->htab_shift - 18);
-        if (kvmppc_put_books_sregs(cpu) < 0) {
-            error_report("Unable to update SDR1 in KVM");
-            exit(1);
+        target_ulong sdr1 = spapr_get_hpt_pointer(spapr);
+        if (sdr1) {
+            env->spr[SPR_SDR1] = sdr1;
+            if (kvmppc_put_books_sregs(cpu) < 0) {
+                error_report("Unable to update SDR1 in KVM");
+                exit(1);
+            }
         }
     }
 }
diff --git a/hw/ppc/spapr_hcall.c b/hw/ppc/spapr_hcall.c
index 6ab8c188f381..06059b44ab40 100644
--- a/hw/ppc/spapr_hcall.c
+++ b/hw/ppc/spapr_hcall.c
@@ -735,9 +735,10 @@ static target_ulong h_resize_hpt_commit(PowerPCCPU *cpu,
 
         if (kvm_enabled()) {
             /* For KVM PR, update the HPT pointer */
-            target_ulong sdr1 = (target_ulong)(uintptr_t)spapr->htab
-                | (spapr->htab_shift - 18);
-            kvmppc_update_sdr1(sdr1);
+            target_ulong sdr1 = spapr_get_hpt_pointer(spapr);
+            if (sdr1) {
+                kvmppc_update_sdr1(sdr1);
+            }
         }
 
         pending->hpt = NULL; /* so it's not free()d */
@@ -1566,9 +1567,10 @@ static target_ulong h_client_architecture_support(PowerPCCPU *cpu,
             spapr_reallocate_hpt(spapr, maxshift, &error_fatal);
             if (kvm_enabled()) {
                 /* For KVM PR, update the HPT pointer */
-                target_ulong sdr1 = (target_ulong)(uintptr_t)spapr->htab
-                    | (spapr->htab_shift - 18);
-                kvmppc_update_sdr1(sdr1);
+                target_ulong sdr1 = spapr_get_hpt_pointer(spapr);
+                if (sdr1) {
+                    kvmppc_update_sdr1(sdr1);
+                }
             }
         }
     }
diff --git a/include/hw/ppc/spapr.h b/include/hw/ppc/spapr.h
index c1b365f56431..a1f5edc15018 100644
--- a/include/hw/ppc/spapr.h
+++ b/include/hw/ppc/spapr.h
@@ -709,4 +709,5 @@ void spapr_do_system_reset_on_cpu(CPUState *cs, run_on_cpu_data arg);
 int spapr_vcpu_id(PowerPCCPU *cpu);
 PowerPCCPU *spapr_find_cpu(int vcpu_id);
 
+target_ulong spapr_get_hpt_pointer(sPAPRMachineState *spapr);
 #endif /* HW_SPAPR_H */

On Mon, Sep 04, 2017 at 11:47:05PM +0200, Greg Kurz wrote:
> The formula used to compute the address of the HPT allocated by QEMU is
> open-coded in several places. This patch moves the magic to a dedicated
> helper. While here, we also patch the callers to only pass the address
> to KVM if we indeed have a userland HPT (ie, KVM PR).

The helper function seems reasonable, though I'm not sure about the
name (a. it's not just a pointer, since it includes the encoded size
and b. the name doesn't indicate this is basically KVM PR specific).

THe "only pass the address to KVM if we indeed have a userland HPT
(ie, KVM PR)" bit doesn't really work.  You're doing it by testing for
(sdr1 != 0), but that can only be true if the HPT is minimum size,
which doesn't have much to do with anything meaningful.

> Signed-off-by: Greg Kurz <groug@kaod.org>
> ---
>  hw/ppc/spapr.c          |    9 +++++++++
>  hw/ppc/spapr_cpu_core.c |   12 +++++++-----
>  hw/ppc/spapr_hcall.c    |   14 ++++++++------
>  include/hw/ppc/spapr.h  |    1 +
>  4 files changed, 25 insertions(+), 11 deletions(-)
> 
> diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
> index caffa1276328..bf24c26b756d 100644
> --- a/hw/ppc/spapr.c
> +++ b/hw/ppc/spapr.c
> @@ -1290,6 +1290,15 @@ static void spapr_store_hpte(PPCVirtualHypervisor *vhyp, hwaddr ptex,
>      }
>  }
>  
> +target_ulong spapr_get_hpt_pointer(sPAPRMachineState *spapr)
> +{
> +    if (!spapr->htab) {
> +        return 0;
> +    }
> +
> +    return (target_ulong)(uintptr_t)spapr->htab | (spapr->htab_shift - 18);
> +}
> +
>  int spapr_hpt_shift_for_ramsize(uint64_t ramsize)
>  {
>      int shift;
> diff --git a/hw/ppc/spapr_cpu_core.c b/hw/ppc/spapr_cpu_core.c
> index 85037ef71e27..581eb4d92de9 100644
> --- a/hw/ppc/spapr_cpu_core.c
> +++ b/hw/ppc/spapr_cpu_core.c
> @@ -93,11 +93,13 @@ static void spapr_cpu_reset(void *opaque)
>       * HPT
>       */
>      if (kvm_enabled()) {
> -        env->spr[SPR_SDR1] = (target_ulong)(uintptr_t)spapr->htab
> -            | (spapr->htab_shift - 18);
> -        if (kvmppc_put_books_sregs(cpu) < 0) {
> -            error_report("Unable to update SDR1 in KVM");
> -            exit(1);
> +        target_ulong sdr1 = spapr_get_hpt_pointer(spapr);
> +        if (sdr1) {
> +            env->spr[SPR_SDR1] = sdr1;
> +            if (kvmppc_put_books_sregs(cpu) < 0) {
> +                error_report("Unable to update SDR1 in KVM");
> +                exit(1);
> +            }
>          }
>      }
>  }
> diff --git a/hw/ppc/spapr_hcall.c b/hw/ppc/spapr_hcall.c
> index 6ab8c188f381..06059b44ab40 100644
> --- a/hw/ppc/spapr_hcall.c
> +++ b/hw/ppc/spapr_hcall.c
> @@ -735,9 +735,10 @@ static target_ulong h_resize_hpt_commit(PowerPCCPU *cpu,
>  
>          if (kvm_enabled()) {
>              /* For KVM PR, update the HPT pointer */
> -            target_ulong sdr1 = (target_ulong)(uintptr_t)spapr->htab
> -                | (spapr->htab_shift - 18);
> -            kvmppc_update_sdr1(sdr1);
> +            target_ulong sdr1 = spapr_get_hpt_pointer(spapr);
> +            if (sdr1) {
> +                kvmppc_update_sdr1(sdr1);
> +            }
>          }
>  
>          pending->hpt = NULL; /* so it's not free()d */
> @@ -1566,9 +1567,10 @@ static target_ulong h_client_architecture_support(PowerPCCPU *cpu,
>              spapr_reallocate_hpt(spapr, maxshift, &error_fatal);
>              if (kvm_enabled()) {
>                  /* For KVM PR, update the HPT pointer */
> -                target_ulong sdr1 = (target_ulong)(uintptr_t)spapr->htab
> -                    | (spapr->htab_shift - 18);
> -                kvmppc_update_sdr1(sdr1);
> +                target_ulong sdr1 = spapr_get_hpt_pointer(spapr);
> +                if (sdr1) {
> +                    kvmppc_update_sdr1(sdr1);
> +                }
>              }
>          }
>      }
> diff --git a/include/hw/ppc/spapr.h b/include/hw/ppc/spapr.h
> index c1b365f56431..a1f5edc15018 100644
> --- a/include/hw/ppc/spapr.h
> +++ b/include/hw/ppc/spapr.h
> @@ -709,4 +709,5 @@ void spapr_do_system_reset_on_cpu(CPUState *cs, run_on_cpu_data arg);
>  int spapr_vcpu_id(PowerPCCPU *cpu);
>  PowerPCCPU *spapr_find_cpu(int vcpu_id);
>  
> +target_ulong spapr_get_hpt_pointer(sPAPRMachineState *spapr);
>  #endif /* HW_SPAPR_H */
> 

-- 
David Gibson			| I'll have my music baroque, and my code
david AT gibson.dropbear.id.au	| minimalist, thank you.  NOT _the_ _other_
				| _way_ _around_!
http://www.ozlabs.org/~dgibson

On Sun, 10 Sep 2017 13:41:41 +1000
David Gibson <david@gibson.dropbear.id.au> wrote:

> On Mon, Sep 04, 2017 at 11:47:05PM +0200, Greg Kurz wrote:
> > The formula used to compute the address of the HPT allocated by QEMU is
> > open-coded in several places. This patch moves the magic to a dedicated
> > helper. While here, we also patch the callers to only pass the address
> > to KVM if we indeed have a userland HPT (ie, KVM PR).  
> 
> The helper function seems reasonable, though I'm not sure about the
> name (a. it's not just a pointer, since it includes the encoded size
> and b. the name doesn't indicate this is basically KVM PR specific).
> 

Sure, I'll come up with a better name.

> THe "only pass the address to KVM if we indeed have a userland HPT
> (ie, KVM PR)" bit doesn't really work.  You're doing it by testing for
> (sdr1 != 0), but that can only be true if the HPT is minimum size,
> which doesn't have much to do with anything meaningful.
> 

Hmmm... if QEMU has allocated an HPT in userspace then the helper
necessarily returns a non-null value, no matter the HPT size. Am
I missing something ?

> > Signed-off-by: Greg Kurz <groug@kaod.org>
> > ---
> >  hw/ppc/spapr.c          |    9 +++++++++
> >  hw/ppc/spapr_cpu_core.c |   12 +++++++-----
> >  hw/ppc/spapr_hcall.c    |   14 ++++++++------
> >  include/hw/ppc/spapr.h  |    1 +
> >  4 files changed, 25 insertions(+), 11 deletions(-)
> > 
> > diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
> > index caffa1276328..bf24c26b756d 100644
> > --- a/hw/ppc/spapr.c
> > +++ b/hw/ppc/spapr.c
> > @@ -1290,6 +1290,15 @@ static void spapr_store_hpte(PPCVirtualHypervisor *vhyp, hwaddr ptex,
> >      }
> >  }
> >  
> > +target_ulong spapr_get_hpt_pointer(sPAPRMachineState *spapr)
> > +{
> > +    if (!spapr->htab) {
> > +        return 0;
> > +    }
> > +
> > +    return (target_ulong)(uintptr_t)spapr->htab | (spapr->htab_shift - 18);
> > +}
> > +
> >  int spapr_hpt_shift_for_ramsize(uint64_t ramsize)
> >  {
> >      int shift;
> > diff --git a/hw/ppc/spapr_cpu_core.c b/hw/ppc/spapr_cpu_core.c
> > index 85037ef71e27..581eb4d92de9 100644
> > --- a/hw/ppc/spapr_cpu_core.c
> > +++ b/hw/ppc/spapr_cpu_core.c
> > @@ -93,11 +93,13 @@ static void spapr_cpu_reset(void *opaque)
> >       * HPT
> >       */
> >      if (kvm_enabled()) {
> > -        env->spr[SPR_SDR1] = (target_ulong)(uintptr_t)spapr->htab
> > -            | (spapr->htab_shift - 18);
> > -        if (kvmppc_put_books_sregs(cpu) < 0) {
> > -            error_report("Unable to update SDR1 in KVM");
> > -            exit(1);
> > +        target_ulong sdr1 = spapr_get_hpt_pointer(spapr);
> > +        if (sdr1) {
> > +            env->spr[SPR_SDR1] = sdr1;
> > +            if (kvmppc_put_books_sregs(cpu) < 0) {
> > +                error_report("Unable to update SDR1 in KVM");
> > +                exit(1);
> > +            }
> >          }
> >      }
> >  }
> > diff --git a/hw/ppc/spapr_hcall.c b/hw/ppc/spapr_hcall.c
> > index 6ab8c188f381..06059b44ab40 100644
> > --- a/hw/ppc/spapr_hcall.c
> > +++ b/hw/ppc/spapr_hcall.c
> > @@ -735,9 +735,10 @@ static target_ulong h_resize_hpt_commit(PowerPCCPU *cpu,
> >  
> >          if (kvm_enabled()) {
> >              /* For KVM PR, update the HPT pointer */
> > -            target_ulong sdr1 = (target_ulong)(uintptr_t)spapr->htab
> > -                | (spapr->htab_shift - 18);
> > -            kvmppc_update_sdr1(sdr1);
> > +            target_ulong sdr1 = spapr_get_hpt_pointer(spapr);
> > +            if (sdr1) {
> > +                kvmppc_update_sdr1(sdr1);
> > +            }
> >          }
> >  
> >          pending->hpt = NULL; /* so it's not free()d */
> > @@ -1566,9 +1567,10 @@ static target_ulong h_client_architecture_support(PowerPCCPU *cpu,
> >              spapr_reallocate_hpt(spapr, maxshift, &error_fatal);
> >              if (kvm_enabled()) {
> >                  /* For KVM PR, update the HPT pointer */
> > -                target_ulong sdr1 = (target_ulong)(uintptr_t)spapr->htab
> > -                    | (spapr->htab_shift - 18);
> > -                kvmppc_update_sdr1(sdr1);
> > +                target_ulong sdr1 = spapr_get_hpt_pointer(spapr);
> > +                if (sdr1) {
> > +                    kvmppc_update_sdr1(sdr1);
> > +                }
> >              }
> >          }
> >      }
> > diff --git a/include/hw/ppc/spapr.h b/include/hw/ppc/spapr.h
> > index c1b365f56431..a1f5edc15018 100644
> > --- a/include/hw/ppc/spapr.h
> > +++ b/include/hw/ppc/spapr.h
> > @@ -709,4 +709,5 @@ void spapr_do_system_reset_on_cpu(CPUState *cs, run_on_cpu_data arg);
> >  int spapr_vcpu_id(PowerPCCPU *cpu);
> >  PowerPCCPU *spapr_find_cpu(int vcpu_id);
> >  
> > +target_ulong spapr_get_hpt_pointer(sPAPRMachineState *spapr);
> >  #endif /* HW_SPAPR_H */
> >   
> 

On Mon, Sep 11, 2017 at 02:04:37PM +0200, Greg Kurz wrote:
> On Sun, 10 Sep 2017 13:41:41 +1000
> David Gibson <david@gibson.dropbear.id.au> wrote:
> 
> > On Mon, Sep 04, 2017 at 11:47:05PM +0200, Greg Kurz wrote:
> > > The formula used to compute the address of the HPT allocated by QEMU is
> > > open-coded in several places. This patch moves the magic to a dedicated
> > > helper. While here, we also patch the callers to only pass the address
> > > to KVM if we indeed have a userland HPT (ie, KVM PR).  
> > 
> > The helper function seems reasonable, though I'm not sure about the
> > name (a. it's not just a pointer, since it includes the encoded size
> > and b. the name doesn't indicate this is basically KVM PR specific).
> > 
> 
> Sure, I'll come up with a better name.
> 
> > THe "only pass the address to KVM if we indeed have a userland HPT
> > (ie, KVM PR)" bit doesn't really work.  You're doing it by testing for
> > (sdr1 != 0), but that can only be true if the HPT is minimum size,
> > which doesn't have much to do with anything meaningful.
> > 
> 
> Hmmm... if QEMU has allocated an HPT in userspace then the helper
> necessarily returns a non-null value, no matter the HPT size. Am
> I missing something ?

Yes, but the reverse is not true.  Even if qemu *hasn't* allocated an
HPT in userspace, it will usually return a non-zero value - the only
case it won't is when the HPT is minimum size.  That makes the test
pretty pointless.

> 
> > > Signed-off-by: Greg Kurz <groug@kaod.org>
> > > ---
> > >  hw/ppc/spapr.c          |    9 +++++++++
> > >  hw/ppc/spapr_cpu_core.c |   12 +++++++-----
> > >  hw/ppc/spapr_hcall.c    |   14 ++++++++------
> > >  include/hw/ppc/spapr.h  |    1 +
> > >  4 files changed, 25 insertions(+), 11 deletions(-)
> > > 
> > > diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
> > > index caffa1276328..bf24c26b756d 100644
> > > --- a/hw/ppc/spapr.c
> > > +++ b/hw/ppc/spapr.c
> > > @@ -1290,6 +1290,15 @@ static void spapr_store_hpte(PPCVirtualHypervisor *vhyp, hwaddr ptex,
> > >      }
> > >  }
> > >  
> > > +target_ulong spapr_get_hpt_pointer(sPAPRMachineState *spapr)
> > > +{
> > > +    if (!spapr->htab) {
> > > +        return 0;
> > > +    }
> > > +
> > > +    return (target_ulong)(uintptr_t)spapr->htab | (spapr->htab_shift - 18);
> > > +}
> > > +
> > >  int spapr_hpt_shift_for_ramsize(uint64_t ramsize)
> > >  {
> > >      int shift;
> > > diff --git a/hw/ppc/spapr_cpu_core.c b/hw/ppc/spapr_cpu_core.c
> > > index 85037ef71e27..581eb4d92de9 100644
> > > --- a/hw/ppc/spapr_cpu_core.c
> > > +++ b/hw/ppc/spapr_cpu_core.c
> > > @@ -93,11 +93,13 @@ static void spapr_cpu_reset(void *opaque)
> > >       * HPT
> > >       */
> > >      if (kvm_enabled()) {
> > > -        env->spr[SPR_SDR1] = (target_ulong)(uintptr_t)spapr->htab
> > > -            | (spapr->htab_shift - 18);
> > > -        if (kvmppc_put_books_sregs(cpu) < 0) {
> > > -            error_report("Unable to update SDR1 in KVM");
> > > -            exit(1);
> > > +        target_ulong sdr1 = spapr_get_hpt_pointer(spapr);
> > > +        if (sdr1) {
> > > +            env->spr[SPR_SDR1] = sdr1;
> > > +            if (kvmppc_put_books_sregs(cpu) < 0) {
> > > +                error_report("Unable to update SDR1 in KVM");
> > > +                exit(1);
> > > +            }
> > >          }
> > >      }
> > >  }
> > > diff --git a/hw/ppc/spapr_hcall.c b/hw/ppc/spapr_hcall.c
> > > index 6ab8c188f381..06059b44ab40 100644
> > > --- a/hw/ppc/spapr_hcall.c
> > > +++ b/hw/ppc/spapr_hcall.c
> > > @@ -735,9 +735,10 @@ static target_ulong h_resize_hpt_commit(PowerPCCPU *cpu,
> > >  
> > >          if (kvm_enabled()) {
> > >              /* For KVM PR, update the HPT pointer */
> > > -            target_ulong sdr1 = (target_ulong)(uintptr_t)spapr->htab
> > > -                | (spapr->htab_shift - 18);
> > > -            kvmppc_update_sdr1(sdr1);
> > > +            target_ulong sdr1 = spapr_get_hpt_pointer(spapr);
> > > +            if (sdr1) {
> > > +                kvmppc_update_sdr1(sdr1);
> > > +            }
> > >          }
> > >  
> > >          pending->hpt = NULL; /* so it's not free()d */
> > > @@ -1566,9 +1567,10 @@ static target_ulong h_client_architecture_support(PowerPCCPU *cpu,
> > >              spapr_reallocate_hpt(spapr, maxshift, &error_fatal);
> > >              if (kvm_enabled()) {
> > >                  /* For KVM PR, update the HPT pointer */
> > > -                target_ulong sdr1 = (target_ulong)(uintptr_t)spapr->htab
> > > -                    | (spapr->htab_shift - 18);
> > > -                kvmppc_update_sdr1(sdr1);
> > > +                target_ulong sdr1 = spapr_get_hpt_pointer(spapr);
> > > +                if (sdr1) {
> > > +                    kvmppc_update_sdr1(sdr1);
> > > +                }
> > >              }
> > >          }
> > >      }
> > > diff --git a/include/hw/ppc/spapr.h b/include/hw/ppc/spapr.h
> > > index c1b365f56431..a1f5edc15018 100644
> > > --- a/include/hw/ppc/spapr.h
> > > +++ b/include/hw/ppc/spapr.h
> > > @@ -709,4 +709,5 @@ void spapr_do_system_reset_on_cpu(CPUState *cs, run_on_cpu_data arg);
> > >  int spapr_vcpu_id(PowerPCCPU *cpu);
> > >  PowerPCCPU *spapr_find_cpu(int vcpu_id);
> > >  
> > > +target_ulong spapr_get_hpt_pointer(sPAPRMachineState *spapr);
> > >  #endif /* HW_SPAPR_H */
> > >   
> > 
> 



-- 
David Gibson			| I'll have my music baroque, and my code
david AT gibson.dropbear.id.au	| minimalist, thank you.  NOT _the_ _other_
				| _way_ _around_!
http://www.ozlabs.org/~dgibson

On Mon, 11 Sep 2017 22:50:45 +1000
David Gibson <david@gibson.dropbear.id.au> wrote:

> On Mon, Sep 11, 2017 at 02:04:37PM +0200, Greg Kurz wrote:
> > On Sun, 10 Sep 2017 13:41:41 +1000
> > David Gibson <david@gibson.dropbear.id.au> wrote:
> >   
> > > On Mon, Sep 04, 2017 at 11:47:05PM +0200, Greg Kurz wrote:  
> > > > The formula used to compute the address of the HPT allocated by QEMU is
> > > > open-coded in several places. This patch moves the magic to a dedicated
> > > > helper. While here, we also patch the callers to only pass the address
> > > > to KVM if we indeed have a userland HPT (ie, KVM PR).    
> > > 
> > > The helper function seems reasonable, though I'm not sure about the
> > > name (a. it's not just a pointer, since it includes the encoded size
> > > and b. the name doesn't indicate this is basically KVM PR specific).
> > >   
> > 
> > Sure, I'll come up with a better name.
> >   
> > > THe "only pass the address to KVM if we indeed have a userland HPT
> > > (ie, KVM PR)" bit doesn't really work.  You're doing it by testing for
> > > (sdr1 != 0), but that can only be true if the HPT is minimum size,
> > > which doesn't have much to do with anything meaningful.
> > >   
> > 
> > Hmmm... if QEMU has allocated an HPT in userspace then the helper
> > necessarily returns a non-null value, no matter the HPT size. Am
> > I missing something ?  
> 
> Yes, but the reverse is not true.  Even if qemu *hasn't* allocated an
> HPT in userspace, it will usually return a non-zero value - the only
> case it won't is when the HPT is minimum size.  That makes the test
> pretty pointless.
> 

The helper does return 0 if QEMU hasn't allocated an HPT in userspace.

[...]
> > > > +target_ulong spapr_get_hpt_pointer(sPAPRMachineState *spapr)
> > > > +{
> > > > +    if (!spapr->htab) {
> > > > +        return 0;
> > > > +    }
> > > > +
> > > > +    return (target_ulong)(uintptr_t)spapr->htab | (spapr->htab_shift - 18);
> > > > +}
> > > > +

but I agree the patch isn't good... for the comprehension at least. I'll
rework the patchset.

Also this causes a behavior change: we won't update SDR1 anymore with KVM HV,
which already handles it BTW.

void kvmppc_set_hpt(struct kvm *kvm, struct kvm_hpt_info *info)
{
	atomic64_set(&kvm->arch.mmio_update, 0);
	kvm->arch.hpt = *info;
	kvm->arch.sdr1 = __pa(info->virt) | (info->order - 18);

Maybe I should push this behavior change to a separate patch anyway...