xics/kvm: Fix issues with older KVMs on POWER9 hosts

[Qemu-devel] [PATCH 1/3] xics/spapr: Prevent RTAS/hypercalls emulation to be used by in-kernel XICS

Posted by Greg Kurz 6 years, 5 months ago

The XICS-related RTAS calls and hypercalls in QEMU are supposed to be
called only when the KVM in-kernel XICS is in use.

Add some explicit checks to detect that, print an error message and report
an hardware error to the guest.

Signed-off-by: Greg Kurz <groug@kaod.org>
---
 hw/intc/xics_spapr.c |   46 ++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 46 insertions(+)

diff --git a/hw/intc/xics_spapr.c b/hw/intc/xics_spapr.c
index 5a1835e8b1ed..d470ab5f7a2a 100644
--- a/hw/intc/xics_spapr.c
+++ b/hw/intc/xics_spapr.c
@@ -41,11 +41,31 @@
  * Guest interfaces
  */
 
+static bool check_in_kernel_xics(const char *func)
+{
+    if (kvm_irqchip_in_kernel()) {
+        error_report("pseries: %s must never be called for in-kernel XICS",
+                     func);
+        return true;
+    }
+
+    return false;
+}
+
+#define CHECK_IN_KERNEL_XICS_HCALL              \
+    do {                                        \
+        if (check_in_kernel_xics(__func__)) {   \
+            return H_HARDWARE;                  \
+        }                                       \
+    } while (0)
+
 static target_ulong h_cppr(PowerPCCPU *cpu, SpaprMachineState *spapr,
                            target_ulong opcode, target_ulong *args)
 {
     target_ulong cppr = args[0];
 
+    CHECK_IN_KERNEL_XICS_HCALL;
+
     icp_set_cppr(spapr_cpu_state(cpu)->icp, cppr);
     return H_SUCCESS;
 }
@@ -56,6 +76,8 @@ static target_ulong h_ipi(PowerPCCPU *cpu, SpaprMachineState *spapr,
     target_ulong mfrr = args[1];
     ICPState *icp = xics_icp_get(XICS_FABRIC(spapr), args[0]);
 
+    CHECK_IN_KERNEL_XICS_HCALL;
+
     if (!icp) {
         return H_PARAMETER;
     }
@@ -69,6 +91,8 @@ static target_ulong h_xirr(PowerPCCPU *cpu, SpaprMachineState *spapr,
 {
     uint32_t xirr = icp_accept(spapr_cpu_state(cpu)->icp);
 
+    CHECK_IN_KERNEL_XICS_HCALL;
+
     args[0] = xirr;
     return H_SUCCESS;
 }
@@ -78,6 +102,8 @@ static target_ulong h_xirr_x(PowerPCCPU *cpu, SpaprMachineState *spapr,
 {
     uint32_t xirr = icp_accept(spapr_cpu_state(cpu)->icp);
 
+    CHECK_IN_KERNEL_XICS_HCALL;
+
     args[0] = xirr;
     args[1] = cpu_get_host_ticks();
     return H_SUCCESS;
@@ -88,6 +114,8 @@ static target_ulong h_eoi(PowerPCCPU *cpu, SpaprMachineState *spapr,
 {
     target_ulong xirr = args[0];
 
+    CHECK_IN_KERNEL_XICS_HCALL;
+
     icp_eoi(spapr_cpu_state(cpu)->icp, xirr);
     return H_SUCCESS;
 }
@@ -99,6 +127,8 @@ static target_ulong h_ipoll(PowerPCCPU *cpu, SpaprMachineState *spapr,
     uint32_t mfrr;
     uint32_t xirr;
 
+    CHECK_IN_KERNEL_XICS_HCALL;
+
     if (!icp) {
         return H_PARAMETER;
     }
@@ -111,6 +141,14 @@ static target_ulong h_ipoll(PowerPCCPU *cpu, SpaprMachineState *spapr,
     return H_SUCCESS;
 }
 
+#define CHECK_IN_KERNEL_XICS_RTAS(rets)                 \
+    do {                                                \
+        if (check_in_kernel_xics(__func__)) {           \
+            rtas_st((rets), 0, RTAS_OUT_HW_ERROR);      \
+            return;                                     \
+        }                                               \
+    } while (0)
+
 static void rtas_set_xive(PowerPCCPU *cpu, SpaprMachineState *spapr,
                           uint32_t token,
                           uint32_t nargs, target_ulong args,
@@ -119,6 +157,8 @@ static void rtas_set_xive(PowerPCCPU *cpu, SpaprMachineState *spapr,
     ICSState *ics = spapr->ics;
     uint32_t nr, srcno, server, priority;
 
+    CHECK_IN_KERNEL_XICS_RTAS(rets);
+
     if ((nargs != 3) || (nret != 1)) {
         rtas_st(rets, 0, RTAS_OUT_PARAM_ERROR);
         return;
@@ -152,6 +192,8 @@ static void rtas_get_xive(PowerPCCPU *cpu, SpaprMachineState *spapr,
     ICSState *ics = spapr->ics;
     uint32_t nr, srcno;
 
+    CHECK_IN_KERNEL_XICS_RTAS(rets);
+
     if ((nargs != 1) || (nret != 3)) {
         rtas_st(rets, 0, RTAS_OUT_PARAM_ERROR);
         return;
@@ -182,6 +224,8 @@ static void rtas_int_off(PowerPCCPU *cpu, SpaprMachineState *spapr,
     ICSState *ics = spapr->ics;
     uint32_t nr, srcno;
 
+    CHECK_IN_KERNEL_XICS_RTAS(rets);
+
     if ((nargs != 1) || (nret != 1)) {
         rtas_st(rets, 0, RTAS_OUT_PARAM_ERROR);
         return;
@@ -213,6 +257,8 @@ static void rtas_int_on(PowerPCCPU *cpu, SpaprMachineState *spapr,
     ICSState *ics = spapr->ics;
     uint32_t nr, srcno;
 
+    CHECK_IN_KERNEL_XICS_RTAS(rets);
+
     if ((nargs != 1) || (nret != 1)) {
         rtas_st(rets, 0, RTAS_OUT_PARAM_ERROR);
         return;

Re: [Qemu-devel] [PATCH 1/3] xics/spapr: Prevent RTAS/hypercalls emulation to be used by in-kernel XICS

Posted by David Gibson 6 years, 5 months ago

On Thu, Jun 13, 2019 at 06:44:54PM +0200, Greg Kurz wrote:
> The XICS-related RTAS calls and hypercalls in QEMU are supposed to be
> called only when the KVM in-kernel XICS is in use.

I've applied this, but reversed the sense of the sentence above, which
appears to be the intent.

> 
> Add some explicit checks to detect that, print an error message and report
> an hardware error to the guest.
> 
> Signed-off-by: Greg Kurz <groug@kaod.org>
> ---
>  hw/intc/xics_spapr.c |   46 ++++++++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 46 insertions(+)
> 
> diff --git a/hw/intc/xics_spapr.c b/hw/intc/xics_spapr.c
> index 5a1835e8b1ed..d470ab5f7a2a 100644
> --- a/hw/intc/xics_spapr.c
> +++ b/hw/intc/xics_spapr.c
> @@ -41,11 +41,31 @@
>   * Guest interfaces
>   */
>  
> +static bool check_in_kernel_xics(const char *func)
> +{
> +    if (kvm_irqchip_in_kernel()) {
> +        error_report("pseries: %s must never be called for in-kernel XICS",
> +                     func);
> +        return true;
> +    }
> +
> +    return false;
> +}
> +
> +#define CHECK_IN_KERNEL_XICS_HCALL              \
> +    do {                                        \
> +        if (check_in_kernel_xics(__func__)) {   \
> +            return H_HARDWARE;                  \
> +        }                                       \
> +    } while (0)
> +
>  static target_ulong h_cppr(PowerPCCPU *cpu, SpaprMachineState *spapr,
>                             target_ulong opcode, target_ulong *args)
>  {
>      target_ulong cppr = args[0];
>  
> +    CHECK_IN_KERNEL_XICS_HCALL;
> +
>      icp_set_cppr(spapr_cpu_state(cpu)->icp, cppr);
>      return H_SUCCESS;
>  }
> @@ -56,6 +76,8 @@ static target_ulong h_ipi(PowerPCCPU *cpu, SpaprMachineState *spapr,
>      target_ulong mfrr = args[1];
>      ICPState *icp = xics_icp_get(XICS_FABRIC(spapr), args[0]);
>  
> +    CHECK_IN_KERNEL_XICS_HCALL;
> +
>      if (!icp) {
>          return H_PARAMETER;
>      }
> @@ -69,6 +91,8 @@ static target_ulong h_xirr(PowerPCCPU *cpu, SpaprMachineState *spapr,
>  {
>      uint32_t xirr = icp_accept(spapr_cpu_state(cpu)->icp);
>  
> +    CHECK_IN_KERNEL_XICS_HCALL;
> +
>      args[0] = xirr;
>      return H_SUCCESS;
>  }
> @@ -78,6 +102,8 @@ static target_ulong h_xirr_x(PowerPCCPU *cpu, SpaprMachineState *spapr,
>  {
>      uint32_t xirr = icp_accept(spapr_cpu_state(cpu)->icp);
>  
> +    CHECK_IN_KERNEL_XICS_HCALL;
> +
>      args[0] = xirr;
>      args[1] = cpu_get_host_ticks();
>      return H_SUCCESS;
> @@ -88,6 +114,8 @@ static target_ulong h_eoi(PowerPCCPU *cpu, SpaprMachineState *spapr,
>  {
>      target_ulong xirr = args[0];
>  
> +    CHECK_IN_KERNEL_XICS_HCALL;
> +
>      icp_eoi(spapr_cpu_state(cpu)->icp, xirr);
>      return H_SUCCESS;
>  }
> @@ -99,6 +127,8 @@ static target_ulong h_ipoll(PowerPCCPU *cpu, SpaprMachineState *spapr,
>      uint32_t mfrr;
>      uint32_t xirr;
>  
> +    CHECK_IN_KERNEL_XICS_HCALL;
> +
>      if (!icp) {
>          return H_PARAMETER;
>      }
> @@ -111,6 +141,14 @@ static target_ulong h_ipoll(PowerPCCPU *cpu, SpaprMachineState *spapr,
>      return H_SUCCESS;
>  }
>  
> +#define CHECK_IN_KERNEL_XICS_RTAS(rets)                 \
> +    do {                                                \
> +        if (check_in_kernel_xics(__func__)) {           \
> +            rtas_st((rets), 0, RTAS_OUT_HW_ERROR);      \
> +            return;                                     \
> +        }                                               \
> +    } while (0)
> +
>  static void rtas_set_xive(PowerPCCPU *cpu, SpaprMachineState *spapr,
>                            uint32_t token,
>                            uint32_t nargs, target_ulong args,
> @@ -119,6 +157,8 @@ static void rtas_set_xive(PowerPCCPU *cpu, SpaprMachineState *spapr,
>      ICSState *ics = spapr->ics;
>      uint32_t nr, srcno, server, priority;
>  
> +    CHECK_IN_KERNEL_XICS_RTAS(rets);
> +
>      if ((nargs != 3) || (nret != 1)) {
>          rtas_st(rets, 0, RTAS_OUT_PARAM_ERROR);
>          return;
> @@ -152,6 +192,8 @@ static void rtas_get_xive(PowerPCCPU *cpu, SpaprMachineState *spapr,
>      ICSState *ics = spapr->ics;
>      uint32_t nr, srcno;
>  
> +    CHECK_IN_KERNEL_XICS_RTAS(rets);
> +
>      if ((nargs != 1) || (nret != 3)) {
>          rtas_st(rets, 0, RTAS_OUT_PARAM_ERROR);
>          return;
> @@ -182,6 +224,8 @@ static void rtas_int_off(PowerPCCPU *cpu, SpaprMachineState *spapr,
>      ICSState *ics = spapr->ics;
>      uint32_t nr, srcno;
>  
> +    CHECK_IN_KERNEL_XICS_RTAS(rets);
> +
>      if ((nargs != 1) || (nret != 1)) {
>          rtas_st(rets, 0, RTAS_OUT_PARAM_ERROR);
>          return;
> @@ -213,6 +257,8 @@ static void rtas_int_on(PowerPCCPU *cpu, SpaprMachineState *spapr,
>      ICSState *ics = spapr->ics;
>      uint32_t nr, srcno;
>  
> +    CHECK_IN_KERNEL_XICS_RTAS(rets);
> +
>      if ((nargs != 1) || (nret != 1)) {
>          rtas_st(rets, 0, RTAS_OUT_PARAM_ERROR);
>          return;
> 

-- 
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

Re: [Qemu-devel] [PATCH 1/3] xics/spapr: Prevent RTAS/hypercalls emulation to be used by in-kernel XICS

Posted by Greg Kurz 6 years, 4 months ago

On Fri, 14 Jun 2019 11:34:59 +1000
David Gibson <david@gibson.dropbear.id.au> wrote:

> On Thu, Jun 13, 2019 at 06:44:54PM +0200, Greg Kurz wrote:
> > The XICS-related RTAS calls and hypercalls in QEMU are supposed to be
> > called only when the KVM in-kernel XICS is in use.  
> 
> I've applied this, but reversed the sense of the sentence above, which
> appears to be the intent.
> 

Oops indeed... Thanks !

> > 
> > Add some explicit checks to detect that, print an error message and report
> > an hardware error to the guest.
> > 
> > Signed-off-by: Greg Kurz <groug@kaod.org>
> > ---
> >  hw/intc/xics_spapr.c |   46 ++++++++++++++++++++++++++++++++++++++++++++++
> >  1 file changed, 46 insertions(+)
> > 
> > diff --git a/hw/intc/xics_spapr.c b/hw/intc/xics_spapr.c
> > index 5a1835e8b1ed..d470ab5f7a2a 100644
> > --- a/hw/intc/xics_spapr.c
> > +++ b/hw/intc/xics_spapr.c
> > @@ -41,11 +41,31 @@
> >   * Guest interfaces
> >   */
> >  
> > +static bool check_in_kernel_xics(const char *func)
> > +{
> > +    if (kvm_irqchip_in_kernel()) {
> > +        error_report("pseries: %s must never be called for in-kernel XICS",
> > +                     func);
> > +        return true;
> > +    }
> > +
> > +    return false;
> > +}
> > +
> > +#define CHECK_IN_KERNEL_XICS_HCALL              \
> > +    do {                                        \
> > +        if (check_in_kernel_xics(__func__)) {   \
> > +            return H_HARDWARE;                  \
> > +        }                                       \
> > +    } while (0)
> > +
> >  static target_ulong h_cppr(PowerPCCPU *cpu, SpaprMachineState *spapr,
> >                             target_ulong opcode, target_ulong *args)
> >  {
> >      target_ulong cppr = args[0];
> >  
> > +    CHECK_IN_KERNEL_XICS_HCALL;
> > +
> >      icp_set_cppr(spapr_cpu_state(cpu)->icp, cppr);
> >      return H_SUCCESS;
> >  }
> > @@ -56,6 +76,8 @@ static target_ulong h_ipi(PowerPCCPU *cpu, SpaprMachineState *spapr,
> >      target_ulong mfrr = args[1];
> >      ICPState *icp = xics_icp_get(XICS_FABRIC(spapr), args[0]);
> >  
> > +    CHECK_IN_KERNEL_XICS_HCALL;
> > +
> >      if (!icp) {
> >          return H_PARAMETER;
> >      }
> > @@ -69,6 +91,8 @@ static target_ulong h_xirr(PowerPCCPU *cpu, SpaprMachineState *spapr,
> >  {
> >      uint32_t xirr = icp_accept(spapr_cpu_state(cpu)->icp);
> >  
> > +    CHECK_IN_KERNEL_XICS_HCALL;
> > +
> >      args[0] = xirr;
> >      return H_SUCCESS;
> >  }
> > @@ -78,6 +102,8 @@ static target_ulong h_xirr_x(PowerPCCPU *cpu, SpaprMachineState *spapr,
> >  {
> >      uint32_t xirr = icp_accept(spapr_cpu_state(cpu)->icp);
> >  
> > +    CHECK_IN_KERNEL_XICS_HCALL;
> > +
> >      args[0] = xirr;
> >      args[1] = cpu_get_host_ticks();
> >      return H_SUCCESS;
> > @@ -88,6 +114,8 @@ static target_ulong h_eoi(PowerPCCPU *cpu, SpaprMachineState *spapr,
> >  {
> >      target_ulong xirr = args[0];
> >  
> > +    CHECK_IN_KERNEL_XICS_HCALL;
> > +
> >      icp_eoi(spapr_cpu_state(cpu)->icp, xirr);
> >      return H_SUCCESS;
> >  }
> > @@ -99,6 +127,8 @@ static target_ulong h_ipoll(PowerPCCPU *cpu, SpaprMachineState *spapr,
> >      uint32_t mfrr;
> >      uint32_t xirr;
> >  
> > +    CHECK_IN_KERNEL_XICS_HCALL;
> > +
> >      if (!icp) {
> >          return H_PARAMETER;
> >      }
> > @@ -111,6 +141,14 @@ static target_ulong h_ipoll(PowerPCCPU *cpu, SpaprMachineState *spapr,
> >      return H_SUCCESS;
> >  }
> >  
> > +#define CHECK_IN_KERNEL_XICS_RTAS(rets)                 \
> > +    do {                                                \
> > +        if (check_in_kernel_xics(__func__)) {           \
> > +            rtas_st((rets), 0, RTAS_OUT_HW_ERROR);      \
> > +            return;                                     \
> > +        }                                               \
> > +    } while (0)
> > +
> >  static void rtas_set_xive(PowerPCCPU *cpu, SpaprMachineState *spapr,
> >                            uint32_t token,
> >                            uint32_t nargs, target_ulong args,
> > @@ -119,6 +157,8 @@ static void rtas_set_xive(PowerPCCPU *cpu, SpaprMachineState *spapr,
> >      ICSState *ics = spapr->ics;
> >      uint32_t nr, srcno, server, priority;
> >  
> > +    CHECK_IN_KERNEL_XICS_RTAS(rets);
> > +
> >      if ((nargs != 3) || (nret != 1)) {
> >          rtas_st(rets, 0, RTAS_OUT_PARAM_ERROR);
> >          return;
> > @@ -152,6 +192,8 @@ static void rtas_get_xive(PowerPCCPU *cpu, SpaprMachineState *spapr,
> >      ICSState *ics = spapr->ics;
> >      uint32_t nr, srcno;
> >  
> > +    CHECK_IN_KERNEL_XICS_RTAS(rets);
> > +
> >      if ((nargs != 1) || (nret != 3)) {
> >          rtas_st(rets, 0, RTAS_OUT_PARAM_ERROR);
> >          return;
> > @@ -182,6 +224,8 @@ static void rtas_int_off(PowerPCCPU *cpu, SpaprMachineState *spapr,
> >      ICSState *ics = spapr->ics;
> >      uint32_t nr, srcno;
> >  
> > +    CHECK_IN_KERNEL_XICS_RTAS(rets);
> > +
> >      if ((nargs != 1) || (nret != 1)) {
> >          rtas_st(rets, 0, RTAS_OUT_PARAM_ERROR);
> >          return;
> > @@ -213,6 +257,8 @@ static void rtas_int_on(PowerPCCPU *cpu, SpaprMachineState *spapr,
> >      ICSState *ics = spapr->ics;
> >      uint32_t nr, srcno;
> >  
> > +    CHECK_IN_KERNEL_XICS_RTAS(rets);
> > +
> >      if ((nargs != 1) || (nret != 1)) {
> >          rtas_st(rets, 0, RTAS_OUT_PARAM_ERROR);
> >          return;
> >   
>

[Qemu-devel] [PATCH 1/3] xics/spapr: Prevent RTAS/hypercalls emulation to be used by in-kernel XICS
[Qemu-devel] [PATCH 2/3] xics/spapr: Register RTAS/hypercalls once at machine init
[Qemu-devel] [PATCH 3/3] xics/spapr: Detect old KVM XICS on POWER9 hosts