HI Marc & Stephen,

Most of engineers are out until New Year's Day.
 
LAN78xx driver uses irq_domain for phy interrupt, but smsc95xx uses polling.
Need to check flow again, you can try that comment out "lan78xx_setup_irq_domain" to
make dev->domain_data.phyirq = 0 which forces PHY polling.
 
Can you share if this is filed on RPI forum?
Also, it would be appreciated if you can create a ticket on Microchip site at
https://www.microchip.com/technical-support/hot-topics

Best Regards,
Woojung

-----Original Message-----
From: Marc Zyngier <redacted>
Sent: Saturday, December 29, 2018 4:42 AM
To: Stefan Wahren <redacted>
Cc: Woojung Huh - C21699 <Woojung.Huh@microchip.com>; Eric Anholt
[off-list ref]; UNGLinuxDriver [off-list ref];
netdev@vger.kernel.org; linux-arm-kernel@lists.infradead.org
Subject: Re: lan78xx: WARNING: irq 79 handler enabled interrupts

On Sat, 29 Dec 2018 00:02:57 +0000,
Stefan Wahren [off-list ref] wrote:

Hi Stephan,

quoted

Hi,
while booting my Raspberry Pi 3 B+ with Linux 4.20 (arm64/defconfig)
i'm getting the following warning:

[   11.005738] irq 79 handler irq_default_primary_handler+0x0/0x8 enabled

interrupts

[...]

quoted

This seems to come from the lan78xx driver, because i don't get this
warning on the RPI 3B (smsc95xx).

What's the approach to fix this issue?  Is it just simply replace
spin_lock_irq() with spin_lock_irqsave() at the right places?

No, this is more pathological than that. The USB framework seems to be
using threaded interrupts, which implies that interrupts are
re-enabled as soon as it has run.

In turn, this driver is using handle_simple_irq() as its flow, which
definitely expect interrupts to be disabled.

I have no insight in how this driver works, but I'm happy to help if
someone explains the interrupt flow of this thing.

	M.

--
Jazz is not dead, it just smell funny.

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel