From: Marc Zyngier <marc.zyngier@arm.com>
To: Stefan Wahren <stefan.wahren@i2se.com>
Cc: Woojung Huh <woojung.huh@microchip.com>,
Eric Anholt <eric@anholt.net>,
Microchip Linux Driver Support <UNGLinuxDriver@microchip.com>,
<netdev@vger.kernel.org>, <linux-arm-kernel@lists.infradead.org>
Subject: Re: lan78xx: WARNING: irq 79 handler enabled interrupts
Date: Sat, 29 Dec 2018 09:41:38 +0000 [thread overview]
Message-ID: <86efa0brfx.wl-marc.zyngier@arm.com> (raw)
In-Reply-To: <1082628525.187562.1546041777025@email.ionos.de>
On Sat, 29 Dec 2018 00:02:57 +0000,
Stefan Wahren <stefan.wahren@i2se.com> wrote:
Hi Stephan,
>
> 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
[...]
> 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.
next prev parent reply other threads:[~2018-12-29 9:41 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-12-29 0:02 lan78xx: WARNING: irq 79 handler enabled interrupts Stefan Wahren
2018-12-29 9:41 ` Marc Zyngier [this message]
2018-12-30 3:25 ` Woojung.Huh
2019-01-01 21:31 ` Stefan Wahren
2019-01-02 21:42 ` Woojung.Huh
2019-02-05 19:57 ` Stefan Wahren
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=86efa0brfx.wl-marc.zyngier@arm.com \
--to=marc.zyngier@arm.com \
--cc=UNGLinuxDriver@microchip.com \
--cc=eric@anholt.net \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=netdev@vger.kernel.org \
--cc=stefan.wahren@i2se.com \
--cc=woojung.huh@microchip.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).