Re: Nobody cared about IRQs at shutdown

From: Alan Stern
Date: Thu Nov 25 2010 - 11:06:12 EST


On Thu, 25 Nov 2010, Alexander E. Patrakov wrote:

> Hello.
>
> After switching my Gentoo desktop from sysvinit + openrc to systemd, I
> started getting "nobody cared" messages about IRQs 16 and 19 (common
> thing: they are assigned to the USB controllers, that's why CC:

According to your listing, they are used by uhci-hcd. Do the messages
go away if you unload uhci-hcd before shutting down?

> linux-usb) at shutdown. Also, instead of shutting down immediately, the
> kernel started waiting for something to time out (and after the timeout,
> it does power off the computer). Adding the "irqpoll" parameter does
> work around the issue. A screen photo illustrating the problem and the
> kernel config are attached.
>
> I didn't try to bisect because there is no known good kernel. I.e., the
> issue doesn't exist without systemd, and I didn't run systemd with
> earlier kernels.
>
> Please help diagnosing and, if possible, fixing this problem.
>
> The broken image at the top of the screen is from extlinux (I use it to
> boot the kernel because I don't like grub).

You may need to debug the uhci-hcd driver. Look into
drivers/usb/host/uhci-hcd.c; the uhci_shutdown() routine ought to be
called and it ought to call uhci_hc_died(), which in turn calls
uhci_reset_hc() in pci-quirks.c, which is supposed to prevent the
controller from generating any IRQs.

Do you have any USB devices attached to bus 3 or bus 6?

Alan Stern

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