On Wednesday, July 10, 2013 05:48:26 PM Toshi Kani wrote: > On Thu, 2013-07-11 at 00:45 +0200, Rafael J. Wysocki wrote: > > On Wednesday, July 10, 2013 02:11:05 AM Rafael J. Wysocki wrote: > > > On Tuesday, July 09, 2013 01:32:42 PM Toshi Kani wrote: > > > > On Mon, 2013-07-08 at 02:10 +0200, Rafael J. Wysocki wrote: > > > > > From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx> > > > > > > > > > > An ACPI_NOTIFY_BUS_CHECK notification means that we should scan the > > > > > entire namespace starting from the given handle even if the device > > > > > represented by that handle is present (other devices below it may > > > > > just have been added). > > > > > > > > > > For this reason, modify acpi_scan_bus_device_check() to always run > > > > > acpi_bus_scan() if the notification being handled is of type > > > > > ACPI_NOTIFY_BUS_CHECK. > > > > > > > > > > Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx> > > > > > Cc: 3.10+ <stable@xxxxxxxxxxxxxxx> > > > > > > > > Acked-by: Toshi Kani <toshi.kani@xxxxxx> > > > > > > > > But, I think we need the additional patch below. > > > > > > Yes, I think you're right. > > > > That said I'd prefer to put the check into acpi_bus_device_attach() like in > > the appended patch. > > That's fine by me. > > Acked-by: Toshi Kani <toshi.kani@xxxxxx> > > Just a minor point, though. Isn't it a bit inconsistent with > device_attach(), which checks dev->driver inside the function? Well, device_attach() may be called from different places while this is the only place where acpi_scan_attach_handler() is called. The check in acpi_bus_device_attach() is easier to follow to me, because it clearly means "we don't need to do anything more if there's a handler", while the check in acpi_scan_attach_handler() makes you wonder "why do we need to return 1 in that case?" and then you need to go to the caller and look at the check of the return value to see "ah, because we don't want that device_attach() to be called then!". > That said, I am OK with either way. Cool. :-) Thanks, Rafael > > --- > > From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx> > > Subject: ACPI / scan: Do not try to attach scan handlers to devices having them > > > > In acpi_bus_device_attach(), if there is an ACPI device object > > for the given handle and that device object has a scan handler > > attached to it already, there's nothing more to do for that handle > > and the function should just return success immediately. Make > > that happen. > > > > Reported-by: Toshi Kani <toshi.kani@xxxxxx> > > Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx> > > --- > > drivers/acpi/scan.c | 3 +++ > > 1 file changed, 3 insertions(+) > > > > Index: linux-pm/drivers/acpi/scan.c > > =================================================================== > > --- linux-pm.orig/drivers/acpi/scan.c > > +++ linux-pm/drivers/acpi/scan.c > > @@ -1984,6 +1984,9 @@ static acpi_status acpi_bus_device_attac > > if (acpi_bus_get_device(handle, &device)) > > return AE_CTRL_DEPTH; > > > > + if (device->handler) > > + return AE_OK; > > + > > ret = acpi_scan_attach_handler(device); > > if (ret) > > return ret > 0 ? AE_OK : AE_CTRL_DEPTH; > > > > -- > > To unsubscribe from this list: send the line "unsubscribe linux-acpi" in > > the body of a message to majordomo@xxxxxxxxxxxxxxx > > More majordomo info at http://vger.kernel.org/majordomo-info.html > > > -- > To unsubscribe from this list: send the line "unsubscribe linux-acpi" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- I speak only for myself. Rafael J. Wysocki, Intel Open Source Technology Center. -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
