Re: nobody cared about IRQ 19 (firewire, on a HP 2510p notebook)

From: Stefan Richter
Date: Sun Mar 30 2008 - 07:12:30 EST


I wrote on 2008-03-21:
Martin Michlmayr wrote:
I just got the following in dmesg a few minutes after booting my
notebook which was idle at the time this occurred. This was with
2.6.25-rc6 but I've seen the same with 2.6.22 (see the attached
dmesg from 2.6.22).

irq 19: nobody cared (try booting with the "irqpoll" option)
Pid: 0, comm: swapper Not tainted 2.6.25-rc6-amd64 #1

Call Trace:
<IRQ> [<ffffffff80271c0b>] __report_bad_irq+0x38/0x7c
[<ffffffff80271e51>] note_interrupt+0x202/0x249
[<ffffffff8027274e>] handle_fasteoi_irq+0xab/0xd0
[<ffffffff8020f82c>] do_IRQ+0x6e/0xda
[<ffffffff8020c65d>] ret_from_intr+0x0/0x19
<EOI> [<ffffffff80221831>] ? native_irq_enable+0x6/0x7
[<ffffffff88006330>] ? :processor:acpi_idle_enter_bm+0x2ab/0x325
[<ffffffff803b5ef3>] ? menu_select+0x70/0x99
[<ffffffff803b52e1>] ? cpuidle_idle_call+0x77/0xa6
[<ffffffff803b526a>] ? cpuidle_idle_call+0x0/0xa6
[<ffffffff8020b187>] ? cpu_idle+0xb1/0xdb
[<ffffffff8042ea16>] ? rest_init+0x5a/0x5c

handlers:
[<ffffffff8806f0f5>] (irq_handler+0x0/0x207 [firewire_ohci])
Disabling IRQ #19
...
02:06.1 FireWire (IEEE 1394): Ricoh Co Ltd R5C832 IEEE 1394 Controller (rev 04)
...

According to your 2.6.22 dmesg, this happens a while after the firewire subsystem seemingly successfully initialized the controller. Could you please post "dmesg | grep firewire" from 2.6.25-rc6 though?

[According to Martin's answer on 2008-03-22, the initialization of firewire-ohci also succeeds without noticeable problem under 2.6.25-rc6.]

The __report_bad_irq() and "Disabling IRQ #..." can only have happened because this condition in fw-ohci.c::irq_handler()

event = reg_read(ohci, OHCI1394_IntEventClear);

if (!event || !~event)
return IRQ_NONE;

happened a lot of times. This means either
- Some MMIO reads return bogus values (all zero or all ones in a
bitfield which should be sparsely populated in a proper interrupt
event),
or
- the interrupt was misrouted by the kernel's IRQ infrastructure was
unable to detect the misrouting, AFAIU.

Martin, please check whether the same happens if you disable firewire-ohci in the kernel config (or blacklist it in the modprobe config) and use the ohci1394 driver instead.

Thanks, and sorry for replying so late,
--
Stefan Richter
-=====-==--- --== ====-
http://arcgraph.de/sr/
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/