# nobody cares about my irq!

## jwalker

I've been playing with a fresh bootstrap of Gentoo using gcc 3.4, glibc 2.3.4 (nptl), and reiser4.  Everything's been going great, but when I reboot with my new love-sources kernel fresh out of the oven, it gave me an error similar to the following:

```
irq 9: nobody cared!

 [<pointer>] __report_bad_irq+0x2a/0x8b

 [<pointer>] note_interrupt+0x6f/0x9f

 [<pointer>] do_IRQ+0x17c/0x1a8

 [<pointer>] common_interrupt+0x18/0x20

 ....

handlers:

[<pointer>] (usb_hcd_irq+0x0/0x67)

Disabling IRQ #9

```

I continued to look into this problem as much as I knew how, but I have yet to resolve it.  I have tried a few different kernels, and it seems as though all of the fairly recent (>=2.6.7) mm-patched kernels are affected by this problem.  When testing, I did not apply the reiser4 patch unless necessary as I did not want any of that code to adversely affect interrupt handling.

By default, one of the uhci devices and the e1000 nic share irq 9, and if I disable the usb controller in bios, then the error just occurs later on when dhcpcd is ran.  If I disable the nic in bios, then the uhci controller generates the error before init is ran.  I also tried changing the IRQ assigned to both to 3, but it oopsed in the interrupt handler (fatal exception in e1000_watchdog) when the init script finished up.  The only way I can avoid a problem (at least I haven't had one yet with this approach) is to either disable the nic and change the irq of the usb controller to 3 or disable both completely.  

I'd really like to figure out the problem, but I do not know much about kernel hacking (or interrupt handling), so it's taking me forever.  Any info would be greatly appreciated.

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## Malakin

I have the same problem, it started when I moved to 2.6.7 so I just went back to 2.6.6 and I'm waiting for 2.6.8 where I'm hoping it will be fixed. (I'm using regular development sources)

If you really want to fix it on your own instead of just waiting for a fix you could figure out which of the revisions from 2.6.6 -> 2.6.7 caused the problem and then figure out which patch caused the problem, from there it would be easy to fix. Although someone's probably already fixed it and the patch it out there somewhere.

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## gazoombo

IIRC there is a USB bug of some kind that causes this error. Look in /proc/interupts and see if ehci_hcd is on that IRQ. If it is, it might be the same problem I had. RAC has a patch for it. 

http://dev.gentoo.org/~rac/ehci-irq.patch

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## Malakin

I'll try the patch out later but I think this is it.

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## Dinini

Just in case that doesn't work.  Your problem sounds alot like http://bugme.osdl.org/show_bug.cgi?id=2243 you could try the patch in comment 89. But first try the patch gazoombo recommended.  :Smile: 

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## jwalker

Thanks guys!  I was finally able to track down the correct bug (and there was a patch out already - released about 2 weeks ago), but would not have known to check out acpi problems without the helpful links   :Smile:  .

If anyone else has a problem similar to this, mine stemmed from an ACPI breakage on DELL workstations.  See the bug report here... http://bugzilla.kernel.org/show_bug.cgi?id=2990

The mm patches were breaking tradtional PIC support, so when ACPI failed and the kernel resorted to PIC interrupt routing as opposed to IO-APIC, everything decided to shat itself.

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## agilen

FYI - The patch that gazoombo posted above worked for ck-sources 2.6.7-r5.

Thanks!

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## gazoombo

Don't thank me, thank RAC. He helped me out on #gentoo and pointed me to the patch.

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## yaneurabeya

 *jwalker wrote:*   

> If anyone else has a problem similar to this, mine stemmed from an ACPI breakage on DELL workstations.  See the bug report here... http://bugzilla.kernel.org/show_bug.cgi?id=2990

 

Great! That's just what I was looking for for fixing my network support when I use ACPI  :Very Happy: .

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