| Message ID | 2806030.VWUMy6F7lm@vostro.rjw.lan (mailing list archive) |
|---|---|
| State | Not Applicable, archived |
| Headers | show |
On Sat, Feb 02, 2013 at 11:18:20PM +0100, Rafael J. Wysocki wrote: > On Saturday, February 02, 2013 09:15:37 PM Rafael J. Wysocki wrote: > > On Saturday, February 02, 2013 03:58:01 PM Greg KH wrote: > [...] > > > > > I know it's more complicated with these types of devices, and I think we > > > are getting closer to the correct solution, I just don't want to ever > > > see duplicate devices in the driver model for the same physical device. > > > > Do you mean two things based on struct device for the same hardware component? > > That's been happening already pretty much forever for every PCI device known > > to the ACPI layer, for PNP and many others. However, those ACPI things are (or > > rather should be, but we're going to clean that up) only for convenience (to be > > able to see the namespace structure and related things in sysfs). So the stuff > > under /sys/devices/LNXSYSTM\:00/ is not "real". In my view it shouldn't even > > be under /sys/devices/ (/sys/firmware/acpi/ seems to be a better place for it), > > but that may be difficult to change without breaking user space (maybe we can > > just symlink it from /sys/devices/ or something). And the ACPI bus type > > shouldn't even exist in my opinion. > > Well, well. > > In fact, the appended patch moves the whole ACPI device nodes tree under > /sys/firmware/acpi/ and I'm not seeing any negative consequences of that on my > test box (events work and so on). User space is quite new on it, though, and > the patch is hackish. Try booting a RHEL 5 image on this type of kernel, or some old Fedora releases, they were sensitive to changes in sysfs. greg k-h
On Sunday, February 03, 2013 07:24:47 PM Greg KH wrote: > On Sat, Feb 02, 2013 at 11:18:20PM +0100, Rafael J. Wysocki wrote: > > On Saturday, February 02, 2013 09:15:37 PM Rafael J. Wysocki wrote: > > > On Saturday, February 02, 2013 03:58:01 PM Greg KH wrote: > > [...] > > > > > > > I know it's more complicated with these types of devices, and I think we > > > > are getting closer to the correct solution, I just don't want to ever > > > > see duplicate devices in the driver model for the same physical device. > > > > > > Do you mean two things based on struct device for the same hardware component? > > > That's been happening already pretty much forever for every PCI device known > > > to the ACPI layer, for PNP and many others. However, those ACPI things are (or > > > rather should be, but we're going to clean that up) only for convenience (to be > > > able to see the namespace structure and related things in sysfs). So the stuff > > > under /sys/devices/LNXSYSTM\:00/ is not "real". In my view it shouldn't even > > > be under /sys/devices/ (/sys/firmware/acpi/ seems to be a better place for it), > > > but that may be difficult to change without breaking user space (maybe we can > > > just symlink it from /sys/devices/ or something). And the ACPI bus type > > > shouldn't even exist in my opinion. > > > > Well, well. > > > > In fact, the appended patch moves the whole ACPI device nodes tree under > > /sys/firmware/acpi/ and I'm not seeing any negative consequences of that on my > > test box (events work and so on). User space is quite new on it, though, and > > the patch is hackish. > > Try booting a RHEL 5 image on this type of kernel, or some old Fedora > releases, they were sensitive to changes in sysfs. Well, I've found a machine where it causes problems to happen. I'll try to add a symlink from /sys/devices to that and see what happens then. Thanks, Rafael
Index: linux-pm/drivers/acpi/scan.c =================================================================== --- linux-pm.orig/drivers/acpi/scan.c +++ linux-pm/drivers/acpi/scan.c @@ -1443,6 +1443,8 @@ void acpi_init_device_object(struct acpi device->flags.match_driver = false; device_initialize(&device->dev); dev_set_uevent_suppress(&device->dev, true); + if (handle == ACPI_ROOT_OBJECT) + device->dev.kobj.parent = acpi_kobj; } void acpi_device_add_finalize(struct acpi_device *device)