On 2020-09-11 05:13, Huacai Chen wrote:
Hi, Marc,
On Thu, Sep 10, 2020 at 6:08 PM Marc Zyngier <maz@xxxxxxxxxx> wrote:
On 2020-09-09 05:09, Huacai Chen wrote:
> Reserve legacy LPC irqs (0~15) to avoid spurious interrupts.
How can they be spurious? Why are they enabled the first place?
This looks like you are papering over a much bigger issue.
The spurious interrupts are probably occurred after kdump and the irq
number is in legacy LPC ranges. I think this is because the old kernel
doesn't (and it can't) disable devices properly so there are stale
interrupts in the kdump case.
I don't really understand why the old kernel can't turn the interrupts
off. Most architectures are able t, why not yours?
Finally, why don't you just shut these interrupts off the first place
in the interrupt controller init? Adding a whole lot of kernel
data structures as a band-aid doesn't strike me as the best possible
idea. Not to mention that if they keep firing, all you are doing
is adding extra overhead.
M.
--
Jazz is not dead. It just smells funny...
