Subject : irq 21: nobody cared 2.6.24-rc1
Submitter : Bongani Hlope <firstname.lastname@example.org>
References : http://lkml.org/lkml/2007/10/25/90
I finally convinced my girlfriend to loan me her iPod. I've been trying to bisect the patch that causes this problem. What I found out was that this seems to be a hardware + timing problem, not software. These are the events that leads to the irq 21: nobody cared
1. You have to connect an iPod before you boot you computer
2. With the 2.6.23 and less kernels this will boot fine and allocate the irq 21 to:
21: IO-APIC-fasteoi ehci_hcd:usb1, uhci_hcd:usb2, uhci_hcd:usb3, uhci_hcd:usb4
but when you boot 2.6.24-rcX kernel, you get the irq 21: nobody care message. After getting that message and try to boot to 2.4.23 or less kernels you will get that message again.
The timing part that I'm talking about is that when I was busy dissecting, some kernel's seem to work fine until I started to boot them the second time. On the boot sequence that seems to work fine, the iPod's screen only switches on when the boot sequence is at starting udev.
The boot sequences that seem to have problems is when the iPod's screen switches on while the kernel is still in it's early boot stages (before it starts userspace).
I would like to close this bug report, until at least Ted finds time to see if the symptoms he sees are the same as mine or there is an easier way to reproduce this.
My "irq 21: nobody cared" problem is the same as the one described in bug #8853, and is related to the bluetooth adapter on the Lenovo X61s laptop. So I'm afraid I can't add much to this bug report. My apologies for any confusion, but the original writeup in LKML: http://lkml.org/lkml/2007/10/25/90 didn't mention anything about an ipod as part of the reproduction.