Bug 4843

Summary:	irq 20: nobody cared
Product:	ACPI	Reporter:	Alexey Dobriyan (adobriyan)
Component:	Config-Interrupts	Assignee:	Shaohua (shaohua.li)
Status:	CLOSED PATCH_ALREADY_AVAILABLE
Severity:	normal	CC:	acpi-bugzilla, akpm, bunk, marko.kohtala, nickpiggin, protasnb
Priority:	P2
Hardware:	i386
OS:	Linux
Kernel Version:	2.6.13-rc1	Subsystem:
Regression:	---	Bisected commit-id:
Attachments:	/var/log/messages Patch to fix VIA chipset problems caused by IRQ packing patch

Description Alexey Dobriyan 2005-07-04 14:27:16 UTC

From: Marko Kohtala <marko.kohtala@gmail.com>
http://marc.theaimsgroup.com/?t=112038967400001&r=1&w=2

2.6.12 worked fine, but soon after it got broken and was still broken just now
[Sun, 3 Jul 2005 14:16:53 +0300 --adobriyan] that I checked git version.

USB Universal Host Controller Interface driver v2.3
<7>Pin 2-12 already programmed
ACPI: PCI Interrupt 0000:00:11.2[D] -> GSI 12 (level, low) -> IRQ 20
PCI: Via IRQ fixup for 0000:00:11.2, from 12 to 4
uhci_hcd 0000:00:11.2: VIA Technologies, Inc. VT82xxxxx UHCI USB 1.1 Controller
uhci_hcd 0000:00:11.2: new USB bus registered, assigned bus number 4
uhci_hcd 0000:00:11.2: irq 20, io base 0x0000cc00
hub 4-0:1.0: USB hub found
hub 4-0:1.0: 2 ports detected
usb 3-1: new low speed USB device using ohci_hcd and address 2
irq 20: nobody cared (try booting with the "irqpoll" option)

Working kernel uses IRQ 12.

Comment 1 Alexey Dobriyan 2005-07-04 14:28:27 UTC

Created attachment 5264 [details]
/var/log/messages

Comment 2 Alexey Dobriyan 2005-07-04 14:31:19 UTC

From: Marko Kohtala <marko.kohtala@gmail.com>

Motherboard is MSI-6380 ver 2, i.e. K7T266 Pro2-RU

Comment 3 Shaohua 2005-07-04 18:00:36 UTC

How about revert below patch?
http://www.kernel.org/git/?p=linux/kernel/git/torvalds/linux-
2.6.git;a=commit;h=c434b7a6aedfe428ad17cd61b21b125a7b7a29ce

Comment 4 Marko Kohtala 2005-07-06 00:35:16 UTC

Yes, reverting this patch removed the problem.
http://www.kernel.org/git/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=c434b7a6aedfe428ad17cd61b21b125a7b7a29ce

Thank you.

I'll be out of reach for few weeks now, so I will not be able to test this patch
in fixed form for you. After that then.

Comment 5 Shaohua 2005-07-06 00:49:23 UTC

The via irq quirk is done after mp_register_gsi, so the above patch breaks it. 
I'll ping Natilie.

Comment 6 Natalie Protasevich 2005-07-06 16:43:11 UTC

Created attachment 5292 [details]
Patch to fix VIA chipset problems caused by IRQ packing patch

Comment 7 Natalie Protasevich 2005-07-06 16:50:32 UTC

Recently, I had another complaint and the patch attached fixed it for the other 
case. The VIA chipset uses 4-bit register for its internal routing, which 
limits it to IRQs below 16. This is a usual ISA range, but IRQs 9,10, 11, and 
13 are not used by traditional ISA devices, and that's what VIA relies upon. My 
patch starts distributing PCI IRQs starting 16, and this breaks VIA.
Marko, please test the patch and let me know if it worked for you.
Thanks,
--Natalie

Comment 8 Marko Kohtala 2005-07-20 04:40:27 UTC

Seems to work with the patch to fix VIA.

Thank you Natalie.

Comment 9 Andrew Morton 2005-07-28 23:20:11 UTC

Natalie's patch is still not present in 2.6.13-rc4!

Could someone please get a copy over to me asap?

Comment 10 Shaohua 2005-07-29 00:47:06 UTC

*** Bug 4960 has been marked as a duplicate of this bug. ***

Comment 11 Natalie Protasevich 2005-07-29 07:02:37 UTC

Andrew, you already have the patches in the -mm tree, they are:
x86-avoid-wasting-irqs-patch-update.patch
x86_64-avoid-wasting-irqs-patch-update.patch

Thanks,
--Natalie

Comment 12 Andrew Morton 2005-07-29 11:36:17 UTC

Ah, thanks.  I'll merge the x86 one and I've asked Andi to ack the x86_64
fix for 2.6.13 as well.

Comment 13 Adrian Bunk 2005-08-08 18:29:31 UTC

The patches are in 2.6.13-rc6.