Re: [PATCH] net: lan78xx: fix "enabled interrupts" warninig

From: Jisheng Zhang
Date: Mon Apr 08 2019 - 21:36:19 EST


On Mon, 8 Apr 2019 10:46:52 +0000 wrote:

>
>
> > > Is this warning specific to any linux version?
> >
> > In theory, no. I only tested 5.0, 4.20, both can reproduce this warning.
> >
> This makes me think that code is fine because it occurs in 4.20 and greater. Or maybe the problem is masked in older. I maybe wrong in assuming that.

Per my understanding, the warning should occur since commit cc89c323a30e
("lan78xx: Use irq_domain for phy interrupt from USB Int. EP")
I just bought a Raspberry Pi 3B+ a few days ago, so I didn't have chance
to check 4.19 and before.

>
> >
> > The warning comes from calling generic_handle_irq() in usb tasklet context.
> > This is not correct.
> >
> > Per my understanding, if there's chained irq, we could introduce extra
> > irqdomain. E.g
> >
> > GIC <--> another irqchip controller <--> HW device
> >
> Correct, IRQ domain is generally used in chained irq controllers.
> Yes, We need to check why irq domain is used in the current driver.
>

It's introduced in the commit cc89c323a30e

Thanks