The spapr_ics_create() function handles errors in a rather convoluted
way, with two local Error * variables. Moreover, failing to parent the
ICS object to the machine should be considered as a bug but it is
currently ignored.

This patch addresses both issues.

Signed-off-by: Greg Kurz <groug@kaod.org>
---
 hw/ppc/spapr.c |   19 ++++++++++++-------
 1 file changed, 12 insertions(+), 7 deletions(-)

diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
index 44f7dc7f40e9..c53989bb10b1 100644
--- a/hw/ppc/spapr.c
+++ b/hw/ppc/spapr.c
@@ -101,21 +101,26 @@ static ICSState *spapr_ics_create(sPAPRMachineState *spapr,
                                   const char *type_ics,
                                   int nr_irqs, Error **errp)
 {
-    Error *err = NULL, *local_err = NULL;
+    Error *local_err = NULL;
     Object *obj;
 
     obj = object_new(type_ics);
-    object_property_add_child(OBJECT(spapr), "ics", obj, NULL);
+    object_property_add_child(OBJECT(spapr), "ics", obj, &error_abort);
     object_property_add_const_link(obj, "xics", OBJECT(spapr), &error_abort);
-    object_property_set_int(obj, nr_irqs, "nr-irqs", &err);
+    object_property_set_int(obj, nr_irqs, "nr-irqs", &local_err);
+    if (local_err) {
+        goto error;
+    }
     object_property_set_bool(obj, true, "realized", &local_err);
-    error_propagate(&err, local_err);
-    if (err) {
-        error_propagate(errp, err);
-        return NULL;
+    if (local_err) {
+        goto error;
     }
 
     return ICS_SIMPLE(obj);
+
+error:
+    error_propagate(errp, local_err);
+    return NULL;
 }
 
 static void xics_system_init(MachineState *machine, int nr_irqs, Error **errp)

On 05/15/2017 01:39 PM, Greg Kurz wrote:
> The spapr_ics_create() function handles errors in a rather convoluted
> way, with two local Error * variables. Moreover, failing to parent the
> ICS object to the machine should be considered as a bug but it is
> currently ignored.

I am not sure what should be done for object_property_add_child()
errors but QEMU generally uses NULL for 'Error **'. It might be 
wrong though.

As for the local error handling, it is following what is described in 
qapi/error.h. Isn't it ?

Cheers,

C. 

 
> This patch addresses both issues.
> 
> Signed-off-by: Greg Kurz <groug@kaod.org>
> ---
>  hw/ppc/spapr.c |   19 ++++++++++++-------
>  1 file changed, 12 insertions(+), 7 deletions(-)
> 
> diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
> index 44f7dc7f40e9..c53989bb10b1 100644
> --- a/hw/ppc/spapr.c
> +++ b/hw/ppc/spapr.c
> @@ -101,21 +101,26 @@ static ICSState *spapr_ics_create(sPAPRMachineState *spapr,
>                                    const char *type_ics,
>                                    int nr_irqs, Error **errp)
>  {
> -    Error *err = NULL, *local_err = NULL;
> +    Error *local_err = NULL;
>      Object *obj;
>  
>      obj = object_new(type_ics);
> -    object_property_add_child(OBJECT(spapr), "ics", obj, NULL);
> +    object_property_add_child(OBJECT(spapr), "ics", obj, &error_abort);
>      object_property_add_const_link(obj, "xics", OBJECT(spapr), &error_abort);
> -    object_property_set_int(obj, nr_irqs, "nr-irqs", &err);
> +    object_property_set_int(obj, nr_irqs, "nr-irqs", &local_err);
> +    if (local_err) {
> +        goto error;
> +    }
>      object_property_set_bool(obj, true, "realized", &local_err);
> -    error_propagate(&err, local_err);
> -    if (err) {
> -        error_propagate(errp, err);
> -        return NULL;
> +    if (local_err) {
> +        goto error;
>      }
>  
>      return ICS_SIMPLE(obj);
> +
> +error:
> +    error_propagate(errp, local_err);
> +    return NULL;
>  }
>  
>  static void xics_system_init(MachineState *machine, int nr_irqs, Error **errp)
> 

On Mon, 15 May 2017 13:59:33 +0200
Cédric Le Goater <clg@kaod.org> wrote:

> On 05/15/2017 01:39 PM, Greg Kurz wrote:
> > The spapr_ics_create() function handles errors in a rather convoluted
> > way, with two local Error * variables. Moreover, failing to parent the
> > ICS object to the machine should be considered as a bug but it is
> > currently ignored.  
> 
> I am not sure what should be done for object_property_add_child()
> errors but QEMU generally uses NULL for 'Error **'. It might be 
> wrong though.
> 
> As for the local error handling, it is following what is described in 
> qapi/error.h. Isn't it ?
> 

Yes, it does follow the "Receive and accumulate multiple errors" recommandation,
but does it make sense to realize the ICS object if we failed to set nr-irqs ?

> Cheers,
> 
> C. 
> 
>  
> > This patch addresses both issues.
> > 
> > Signed-off-by: Greg Kurz <groug@kaod.org>
> > ---
> >  hw/ppc/spapr.c |   19 ++++++++++++-------
> >  1 file changed, 12 insertions(+), 7 deletions(-)
> > 
> > diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
> > index 44f7dc7f40e9..c53989bb10b1 100644
> > --- a/hw/ppc/spapr.c
> > +++ b/hw/ppc/spapr.c
> > @@ -101,21 +101,26 @@ static ICSState *spapr_ics_create(sPAPRMachineState *spapr,
> >                                    const char *type_ics,
> >                                    int nr_irqs, Error **errp)
> >  {
> > -    Error *err = NULL, *local_err = NULL;
> > +    Error *local_err = NULL;
> >      Object *obj;
> >  
> >      obj = object_new(type_ics);
> > -    object_property_add_child(OBJECT(spapr), "ics", obj, NULL);
> > +    object_property_add_child(OBJECT(spapr), "ics", obj, &error_abort);
> >      object_property_add_const_link(obj, "xics", OBJECT(spapr), &error_abort);
> > -    object_property_set_int(obj, nr_irqs, "nr-irqs", &err);
> > +    object_property_set_int(obj, nr_irqs, "nr-irqs", &local_err);
> > +    if (local_err) {
> > +        goto error;
> > +    }
> >      object_property_set_bool(obj, true, "realized", &local_err);
> > -    error_propagate(&err, local_err);
> > -    if (err) {
> > -        error_propagate(errp, err);
> > -        return NULL;
> > +    if (local_err) {
> > +        goto error;
> >      }
> >  
> >      return ICS_SIMPLE(obj);
> > +
> > +error:
> > +    error_propagate(errp, local_err);
> > +    return NULL;
> >  }
> >  
> >  static void xics_system_init(MachineState *machine, int nr_irqs, Error **errp)
> >   
> 

On Mon, May 15, 2017 at 02:06:18PM +0200, Greg Kurz wrote:
> On Mon, 15 May 2017 13:59:33 +0200
> Cédric Le Goater <clg@kaod.org> wrote:
> 
> > On 05/15/2017 01:39 PM, Greg Kurz wrote:
> > > The spapr_ics_create() function handles errors in a rather convoluted
> > > way, with two local Error * variables. Moreover, failing to parent the
> > > ICS object to the machine should be considered as a bug but it is
> > > currently ignored.  
> > 
> > I am not sure what should be done for object_property_add_child()
> > errors but QEMU generally uses NULL for 'Error **'. It might be 
> > wrong though.
> > 
> > As for the local error handling, it is following what is described in 
> > qapi/error.h. Isn't it ?
> > 
> 
> Yes, it does follow the "Receive and accumulate multiple errors" recommandation,
> but does it make sense to realize the ICS object if we failed to set
> nr-irqs ?

Nor is it necessary to have two different local error variables.

-- 
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, May 15, 2017 at 01:39:45PM +0200, Greg Kurz wrote:
> The spapr_ics_create() function handles errors in a rather convoluted
> way, with two local Error * variables. Moreover, failing to parent the
> ICS object to the machine should be considered as a bug but it is
> currently ignored.
> 
> This patch addresses both issues.
> 
> Signed-off-by: Greg Kurz <groug@kaod.org>

Applied to ppc-for-2.10

> ---
>  hw/ppc/spapr.c |   19 ++++++++++++-------
>  1 file changed, 12 insertions(+), 7 deletions(-)
> 
> diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
> index 44f7dc7f40e9..c53989bb10b1 100644
> --- a/hw/ppc/spapr.c
> +++ b/hw/ppc/spapr.c
> @@ -101,21 +101,26 @@ static ICSState *spapr_ics_create(sPAPRMachineState *spapr,
>                                    const char *type_ics,
>                                    int nr_irqs, Error **errp)
>  {
> -    Error *err = NULL, *local_err = NULL;
> +    Error *local_err = NULL;
>      Object *obj;
>  
>      obj = object_new(type_ics);
> -    object_property_add_child(OBJECT(spapr), "ics", obj, NULL);
> +    object_property_add_child(OBJECT(spapr), "ics", obj, &error_abort);
>      object_property_add_const_link(obj, "xics", OBJECT(spapr), &error_abort);
> -    object_property_set_int(obj, nr_irqs, "nr-irqs", &err);
> +    object_property_set_int(obj, nr_irqs, "nr-irqs", &local_err);
> +    if (local_err) {
> +        goto error;
> +    }
>      object_property_set_bool(obj, true, "realized", &local_err);
> -    error_propagate(&err, local_err);
> -    if (err) {
> -        error_propagate(errp, err);
> -        return NULL;
> +    if (local_err) {
> +        goto error;
>      }
>  
>      return ICS_SIMPLE(obj);
> +
> +error:
> +    error_propagate(errp, local_err);
> +    return NULL;
>  }
>  
>  static void xics_system_init(MachineState *machine, int nr_irqs, Error **errp)
> 

-- 
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