[v2,3/5] ACPI: scan: Make acpi_processor_add() check the device enabled bit
Commit Message
From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Modify acpi_processor_add() return an error if _STA returns the enabled
bit clear for the given processor device, so as to avoid using processors
that don't decode their resources, as per the ACPI specification. [1]
Link: https://uefi.org/specs/ACPI/6.5/06_Device_Configuration.html#sta-device-status # [1]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
---
v1 -> v2:
* Move acpi_device_is_enabled() to this patch.
* Change patch ordering.
* Do not check the "functional" _STA bit in acpi_device_is_present().
---
drivers/acpi/acpi_processor.c | 3 +++
drivers/acpi/internal.h | 1 +
drivers/acpi/scan.c | 5 +++++
3 files changed, 9 insertions(+)
Comments
On Tue, Feb 27, 2024 at 10:28 AM Jonathan Cameron
<Jonathan.Cameron@huawei.com> wrote:
>
> On Mon, 26 Feb 2024 17:40:52 +0100
> "Rafael J. Wysocki" <rjw@rjwysocki.net> wrote:
>
> > From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
> >
> > Modify acpi_processor_add() return an error if _STA returns the enabled
> > bit clear for the given processor device, so as to avoid using processors
> > that don't decode their resources, as per the ACPI specification. [1]
> >
> > Link: https://uefi.org/specs/ACPI/6.5/06_Device_Configuration.html#sta-device-status # [1]
> > Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
>
> Sorry for lack of reply on discussion.
No worries.
> Your follow up mails never reached my inbox for some reason
/me blames spam filters somewhere.
> so I just caught up on lore. I'll keep an eye on
> the archives to make sure I don't miss further discussion.
Thanks!
> Agreed that functional isn't relevant here so this patch is correct.
> Also agree that it would be nice to clarify the spec as you mentioned
> to say that bit 1 is reserved if bit 0 of _STA result is clear.
> Depending on interpretation it's either a clarification or a relaxation
> of current statements, so should be uncontroversial (famous last words ;)
Right.
> +CC kangkang so this is on his radar as an ACPI cleanup suggestion.
> For his reference, discussion is here:
> https://lore.kernel.org/linux-acpi/CAJZ5v0jjD=KN0pOuWZZ8DT5yHdu03KgOSHYe3wB7h2vafNa44w@mail.gmail.com/
>
> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Thanks for all of the reviews!
===================================================================
@@ -121,6 +121,7 @@ int acpi_device_setup_files(struct acpi_
void acpi_device_remove_files(struct acpi_device *dev);
void acpi_device_add_finalize(struct acpi_device *device);
void acpi_free_pnp_ids(struct acpi_device_pnp *pnp);
+bool acpi_device_is_enabled(const struct acpi_device *adev);
bool acpi_device_is_present(const struct acpi_device *adev);
bool acpi_device_is_battery(struct acpi_device *adev);
bool acpi_device_is_first_physical_node(struct acpi_device *adev,
===================================================================
@@ -381,6 +381,9 @@ static int acpi_processor_add(struct acp
struct device *dev;
int result = 0;
+ if (!acpi_device_is_enabled(device))
+ return -ENODEV;
+
pr = kzalloc(sizeof(struct acpi_processor), GFP_KERNEL);
if (!pr)
return -ENOMEM;
===================================================================
@@ -1945,6 +1945,11 @@ bool acpi_device_is_present(const struct
return adev->status.present || adev->status.functional;
}
+bool acpi_device_is_enabled(const struct acpi_device *adev)
+{
+ return adev->status.present && adev->status.enabled;
+}
+
static bool acpi_scan_handler_matching(struct acpi_scan_handler *handler,
const char *idstr,
const struct acpi_device_id **matchid)