Re: QUESTION: Network hangs with BP6 and 2.4.x kernels, hardware

[Manfred Spraul]

Ingo Molnar wrote:
> 
> we *already* reorder vector numbers and spread them out as much as
> possible. We do this in 2.2 as well. We did this almost from day 1 of
> IO-APIC support. If any manually allocated IRQ vector creates a '3 vectors
> in the same 16-vector region' situation then thats a bug in hw_irq.h..
> 
I reread the 2.2 and 2.4 code:

2.2 spreads all vectors, even the internal interrupts (tlb flush,
reschedule, timer, call function) are spread.
Hmm. AFAICS there is one bug: 3 interrupts are in priority 5:

CALL_FUNCTION_VECTOR	0x50
IRQ0_TRAP_VECTOR	0x51
irq1: irq0+8		0x59

check arch/i386/kernel/irq.h and assign_irq_vector (io_apic.c)

2.4 spreads the vectors for the external (hardware, from io apic)
interrupts, but 5 ipi vectors have the same priority: reschedule, call
function, tlb invalidate, apic error, spurious interrupt.

But that doesn't explain what happens with ne2k cards: neither 2.2 nor
2.4 have more than 2 interrupts in class for the hardware interrupt
16/19.
With 2.2 I don't have any problems, 2.4 hangs.

--
	Manfred