Re: [gentoo-user] Kernel options and udisk

[Felix Kuperjans]

Dale wrote:
> Howdy,
>
> I was doing a update a while back and noticed a ewarn, enotice or
> something going by. I used the elogviewer to go back and dig it out.
> This is what it says:
>
> Found sources for kernel version:
> 3.5.0-gentoo
> Checking for suitable kernel configuration options...
> ERROR (setup)
>
> CONFIG_USB_SUSPEND: is not set when it should be.
> WARN (setup)
udisks will work without that, but if you try to safely unplug a USB
stick or other USB storage device, an error will occur because udisks is
unable to power off the device before unplugging.
The option is not required for its essential functionality, but it's
definitely useful and does not add any big overhead to the kernel, so I
always enable it and would recommend enabling it unless you have a
strong reason not to set it.
>
> Please check to make sure these options are set correctly.
> Failure to do so may cause unexpected problems.
>
> So, I go into the kernel's menuconfig and find this:
>
> │ CONFIG_USB_SUSPEND: │
> │ │
> │ If you say Y here, you can use driver calls or the sysfs │
> │ "power/control" file to enable or disable autosuspend for │
> │ individual USB peripherals (see │
> │ Documentation/usb/power-management.txt for more details). │
> │ │
> │ Also, USB "remote wakeup" signaling is supported, whereby some │
> │ USB devices (like keyboards and network adapters) can wake up │
> │ their parent hub. That wakeup cascades up the USB tree, and │
> │ could wake the system from states like suspend-to-RAM. │
> │ │
> │ If you are unsure about this, say N here. │
This message is on a lot of important stuff, it just means you will be
able to use USB (at least on *some* machines) without enabling it.
As soon as you have any reason to set it or know what it does, this
recommendation is superfluous. Only take care if the help message says
something like:
* This is usually not needed, so if unsure, say no
* This is highly experimental, ...
* only set this as module ...
* Do not enable unless ...
In such cases, you should be sure what you are doing and usually no
ebuild would require options like that.
> │ │
> │ Symbol: USB_SUSPEND [=n] │
> │ Type : boolean │
> │ Prompt: USB runtime power management (autosuspend) and wakeup │
> │ Defined at drivers/usb/core/Kconfig:41 │
> │ Depends on: USB_SUPPORT [=y] && USB [=y] && PM_RUNTIME [=y] │
> │ Location: │
> │ -> Device Drivers │
> │ -> USB support (USB_SUPPORT [=y]) │
> │ -> Support for Host-side USB (USB [=y])
>
> The important part is about 'if you are unsure about this, say N here'.
> Well, I don't think I need USB remote wakeup or anything so I don't
> think I need this but at the same time, udisk is giving me notice that
> it should be there.
>
> This is a desktop system not a laptop. Do I need to listen to me not
> needing it or udisk that says I do?
This option is only USB relevant and can be used on any laptop / desktop
system / whatever with USB support.
> Opinions?
>
> Dale
>
> :-) :-)
>
> P. S. The only things I have USB right now is my printer and a camera. I
> may have a UPS added to that when I get around to rebooting again. I'm
> not sure on how I will end up connecting it yet.
In case you have no USB sticks and never want to use any USB storage
device, you won't need udisks at all, try disabling the "udisks" USE
flags on your desktop packages (esp. gvfs).

Regards,
Felix