On Fri, 26 Apr 2024 18:56:21 +0200 "Rafael J. Wysocki" <rjw@xxxxxxxxxxxxx> wrote: > From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx> > > The return value of _STA with the "present" bit unset and the "enabled" > bit set is clearly invalid as per the ACPI specification, Section 6.3.7 > "_STA (Device Status)", so make the ACPI device enumeration code > disregard devices with such _STA return values. > > Also, because this implies that status.enabled will only be set if > status.present is set too, acpi_device_is_enabled() can be modified > to simply return the value of the former. > > Link: https://uefi.org/specs/ACPI/6.5/06_Device_Configuration.html#sta-device-status > Link: https://lore.kernel.org/linux-acpi/88179311a503493099028c12ca37d430@xxxxxxxxxx/ > Suggested-by: Salil Mehta <salil.mehta@xxxxxxxxxx> > Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx> Seems a sensible tidying up. Hopefully nothing was relying on this looser behavior. One trivial thing inline. Reviewed-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx> > --- > drivers/acpi/bus.c | 11 +++++++++++ > drivers/acpi/scan.c | 2 +- > 2 files changed, 12 insertions(+), 1 deletion(-) > > Index: linux-pm/drivers/acpi/bus.c > =================================================================== > --- linux-pm.orig/drivers/acpi/bus.c > +++ linux-pm/drivers/acpi/bus.c > @@ -112,6 +112,17 @@ int acpi_bus_get_status(struct acpi_devi > if (ACPI_FAILURE(status)) > return -ENODEV; > > + if (!device->status.present && device->status.enabled) { > + pr_info(FW_BUG "Device [%s] status [%08x]: not present and enabled\n", > + device->pnp.bus_id, (u32)sta); > + device->status.enabled = 0; > + /* > + * The status is clearly invalid, so clear the enabled bit as > + * well to avoid attempting to use the device. > + */ Comment seems to be in a slightly odd place. Perhaps one line earlier makes more sense? Or was the intent to mention functional here? > + device->status.functional = 0; > + } > + > acpi_set_device_status(device, sta); > > if (device->status.functional && !device->status.present) { > Index: linux-pm/drivers/acpi/scan.c > =================================================================== > --- linux-pm.orig/drivers/acpi/scan.c > +++ linux-pm/drivers/acpi/scan.c > @@ -1962,7 +1962,7 @@ bool acpi_device_is_present(const struct > > bool acpi_device_is_enabled(const struct acpi_device *adev) > { > - return adev->status.present && adev->status.enabled; > + return adev->status.enabled; > } > > static bool acpi_scan_handler_matching(struct acpi_scan_handler *handler, > > >
