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[PATCH v1 1/4] ACPI: property: Fix buffer properties extraction for subnodes

Rafael J. Wysocki posted 4 patches 2 weeks, 5 days ago
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[PATCH v1 1/4] ACPI: property: Fix buffer properties extraction for subnodes
Posted by Rafael J. Wysocki 2 weeks, 5 days ago 
From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

The ACPI handle passed to acpi_extract_properties() as the first
argument represents the ACPI namespace scope in which to look for
objects returning buffers associated with buffer properties.

For _DSD objects located immediately under ACPI devices, this handle is
the same as the handle of the device object holding the _DSD, but for
data-only subnodes it is not so.

First of all, data-only subnodes are represented by objects that
cannot hold other objects in their scopes (like control methods).
Therefore a data-only subnode handle cannot be used for completing
relative pathname segments, so the current code in
in acpi_nondev_subnode_extract() passing a data-only subnode handle
to acpi_extract_properties() is invalid.

Moreover, a data-only subnode of device A may be represented by an
object located in the scope of device B (which kind of makes sense,
for instance, if A is a B's child).  In that case, the scope in
question would be the one of device B.  In other words, the scope
mentioned above is the same as the scope used for subnode object
lookup in acpi_nondev_subnode_extract().

Accordingly, rearrange that function to use the same scope for the
extraction of properties and subnode object lookup.

Fixes: 103e10c69c61 ("ACPI: property: Add support for parsing buffer property UUID")
Cc: 6.0+ <stable@vger.kernel.org> # 6.0+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
---
 drivers/acpi/property.c |   30 +++++++++++-------------------
 1 file changed, 11 insertions(+), 19 deletions(-)

--- a/drivers/acpi/property.c
+++ b/drivers/acpi/property.c
@@ -83,6 +83,7 @@ static bool acpi_nondev_subnode_extract(
 					struct fwnode_handle *parent)
 {
 	struct acpi_data_node *dn;
+	acpi_handle scope = NULL;
 	bool result;
 
 	if (acpi_graph_ignore_port(handle))
@@ -98,27 +99,18 @@ static bool acpi_nondev_subnode_extract(
 	INIT_LIST_HEAD(&dn->data.properties);
 	INIT_LIST_HEAD(&dn->data.subnodes);
 
-	result = acpi_extract_properties(handle, desc, &dn->data);
+	/*
+	 * The scope for the completion of relative pathname segments and
+	 * subnode object lookup is the one of the namespace node (device)
+	 * containing the object that has returned the package.  That is, it's
+	 * the scope of that object's parent device.
+	 */
+	if (handle)
+		acpi_get_parent(handle, &scope);
 
-	if (handle) {
-		acpi_handle scope;
-		acpi_status status;
-
-		/*
-		 * The scope for the subnode object lookup is the one of the
-		 * namespace node (device) containing the object that has
-		 * returned the package.  That is, it's the scope of that
-		 * object's parent.
-		 */
-		status = acpi_get_parent(handle, &scope);
-		if (ACPI_SUCCESS(status)
-		    && acpi_enumerate_nondev_subnodes(scope, desc, &dn->data,
-						      &dn->fwnode))
-			result = true;
-	} else if (acpi_enumerate_nondev_subnodes(NULL, desc, &dn->data,
-						  &dn->fwnode)) {
+	result = acpi_extract_properties(scope, desc, &dn->data);
+	if (acpi_enumerate_nondev_subnodes(scope, desc, &dn->data, &dn->fwnode))
 		result = true;
-	}
 
 	if (result) {
 		dn->handle = handle;
Re: [PATCH v1 1/4] ACPI: property: Fix buffer properties extraction for subnodes
Posted by Sakari Ailus 2 weeks, 3 days ago 
Hi Rafael,

On Fri, Sep 12, 2025 at 09:39:52PM +0200, Rafael J. Wysocki wrote:
> From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
> 
> The ACPI handle passed to acpi_extract_properties() as the first
> argument represents the ACPI namespace scope in which to look for
> objects returning buffers associated with buffer properties.
> 
> For _DSD objects located immediately under ACPI devices, this handle is
> the same as the handle of the device object holding the _DSD, but for
> data-only subnodes it is not so.
> 
> First of all, data-only subnodes are represented by objects that
> cannot hold other objects in their scopes (like control methods).
> Therefore a data-only subnode handle cannot be used for completing
> relative pathname segments, so the current code in
> in acpi_nondev_subnode_extract() passing a data-only subnode handle
> to acpi_extract_properties() is invalid.
> 
> Moreover, a data-only subnode of device A may be represented by an
> object located in the scope of device B (which kind of makes sense,
> for instance, if A is a B's child).  In that case, the scope in
> question would be the one of device B.  In other words, the scope
> mentioned above is the same as the scope used for subnode object
> lookup in acpi_nondev_subnode_extract().
> 
> Accordingly, rearrange that function to use the same scope for the
> extraction of properties and subnode object lookup.
> 
> Fixes: 103e10c69c61 ("ACPI: property: Add support for parsing buffer property UUID")

I believe the commit introducing this is
99db5ff7fe0b4e1657423d7bbe2aa8f655dd02d1 .

> Cc: 6.0+ <stable@vger.kernel.org> # 6.0+
> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
> ---
>  drivers/acpi/property.c |   30 +++++++++++-------------------
>  1 file changed, 11 insertions(+), 19 deletions(-)
> 
> --- a/drivers/acpi/property.c
> +++ b/drivers/acpi/property.c
> @@ -83,6 +83,7 @@ static bool acpi_nondev_subnode_extract(
>  					struct fwnode_handle *parent)
>  {
>  	struct acpi_data_node *dn;
> +	acpi_handle scope = NULL;
>  	bool result;
>  
>  	if (acpi_graph_ignore_port(handle))
> @@ -98,27 +99,18 @@ static bool acpi_nondev_subnode_extract(
>  	INIT_LIST_HEAD(&dn->data.properties);
>  	INIT_LIST_HEAD(&dn->data.subnodes);
>  
> -	result = acpi_extract_properties(handle, desc, &dn->data);
> +	/*
> +	 * The scope for the completion of relative pathname segments and
> +	 * subnode object lookup is the one of the namespace node (device)
> +	 * containing the object that has returned the package.  That is, it's
> +	 * the scope of that object's parent device.
> +	 */
> +	if (handle)
> +		acpi_get_parent(handle, &scope);
>  
> -	if (handle) {
> -		acpi_handle scope;
> -		acpi_status status;
> -
> -		/*
> -		 * The scope for the subnode object lookup is the one of the
> -		 * namespace node (device) containing the object that has
> -		 * returned the package.  That is, it's the scope of that
> -		 * object's parent.
> -		 */
> -		status = acpi_get_parent(handle, &scope);
> -		if (ACPI_SUCCESS(status)
> -		    && acpi_enumerate_nondev_subnodes(scope, desc, &dn->data,
> -						      &dn->fwnode))
> -			result = true;
> -	} else if (acpi_enumerate_nondev_subnodes(NULL, desc, &dn->data,
> -						  &dn->fwnode)) {
> +	result = acpi_extract_properties(scope, desc, &dn->data);
> +	if (acpi_enumerate_nondev_subnodes(scope, desc, &dn->data, &dn->fwnode))
>  		result = true;
> -	}
>  
>  	if (result) {
>  		dn->handle = handle;
> 
> 

-- 
Kind regards,

Sakari Ailus
Re: [PATCH v1 1/4] ACPI: property: Fix buffer properties extraction for subnodes
Posted by Rafael J. Wysocki 2 weeks, 3 days ago 
Hi Sakari,

On Mon, Sep 15, 2025 at 1:04 PM Sakari Ailus
<sakari.ailus@linux.intel.com> wrote:
>
> Hi Rafael,
>
> On Fri, Sep 12, 2025 at 09:39:52PM +0200, Rafael J. Wysocki wrote:
> > From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
> >
> > The ACPI handle passed to acpi_extract_properties() as the first
> > argument represents the ACPI namespace scope in which to look for
> > objects returning buffers associated with buffer properties.
> >
> > For _DSD objects located immediately under ACPI devices, this handle is
> > the same as the handle of the device object holding the _DSD, but for
> > data-only subnodes it is not so.
> >
> > First of all, data-only subnodes are represented by objects that
> > cannot hold other objects in their scopes (like control methods).
> > Therefore a data-only subnode handle cannot be used for completing
> > relative pathname segments, so the current code in
> > in acpi_nondev_subnode_extract() passing a data-only subnode handle
> > to acpi_extract_properties() is invalid.
> >
> > Moreover, a data-only subnode of device A may be represented by an
> > object located in the scope of device B (which kind of makes sense,
> > for instance, if A is a B's child).  In that case, the scope in
> > question would be the one of device B.  In other words, the scope
> > mentioned above is the same as the scope used for subnode object
> > lookup in acpi_nondev_subnode_extract().
> >
> > Accordingly, rearrange that function to use the same scope for the
> > extraction of properties and subnode object lookup.
> >
> > Fixes: 103e10c69c61 ("ACPI: property: Add support for parsing buffer property UUID")
>
> I believe the commit introducing this is
> 99db5ff7fe0b4e1657423d7bbe2aa8f655dd02d1 .

No, it isn't.  Prior to commit 103e10c69c61, scope was not passed to
acpi_extract_properties().

> > Cc: 6.0+ <stable@vger.kernel.org> # 6.0+
> > Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
> > ---
> >  drivers/acpi/property.c |   30 +++++++++++-------------------
> >  1 file changed, 11 insertions(+), 19 deletions(-)
> >
> > --- a/drivers/acpi/property.c
> > +++ b/drivers/acpi/property.c
> > @@ -83,6 +83,7 @@ static bool acpi_nondev_subnode_extract(
> >                                       struct fwnode_handle *parent)
> >  {
> >       struct acpi_data_node *dn;
> > +     acpi_handle scope = NULL;
> >       bool result;
> >
> >       if (acpi_graph_ignore_port(handle))
> > @@ -98,27 +99,18 @@ static bool acpi_nondev_subnode_extract(
> >       INIT_LIST_HEAD(&dn->data.properties);
> >       INIT_LIST_HEAD(&dn->data.subnodes);
> >
> > -     result = acpi_extract_properties(handle, desc, &dn->data);
> > +     /*
> > +      * The scope for the completion of relative pathname segments and
> > +      * subnode object lookup is the one of the namespace node (device)
> > +      * containing the object that has returned the package.  That is, it's
> > +      * the scope of that object's parent device.
> > +      */
> > +     if (handle)
> > +             acpi_get_parent(handle, &scope);
> >
> > -     if (handle) {
> > -             acpi_handle scope;
> > -             acpi_status status;
> > -
> > -             /*
> > -              * The scope for the subnode object lookup is the one of the
> > -              * namespace node (device) containing the object that has
> > -              * returned the package.  That is, it's the scope of that
> > -              * object's parent.
> > -              */
> > -             status = acpi_get_parent(handle, &scope);
> > -             if (ACPI_SUCCESS(status)
> > -                 && acpi_enumerate_nondev_subnodes(scope, desc, &dn->data,
> > -                                                   &dn->fwnode))
> > -                     result = true;
> > -     } else if (acpi_enumerate_nondev_subnodes(NULL, desc, &dn->data,
> > -                                               &dn->fwnode)) {
> > +     result = acpi_extract_properties(scope, desc, &dn->data);
> > +     if (acpi_enumerate_nondev_subnodes(scope, desc, &dn->data, &dn->fwnode))
> >               result = true;
> > -     }
> >
> >       if (result) {
> >               dn->handle = handle;
> >
> >
>
> --

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