public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
To: Jakub Kicinski <kuba@kernel.org>
Cc: Marek Vasut <marex@nabladev.com>,
	netdev@vger.kernel.org, stable@vger.kernel.org,
	"David S. Miller" <davem@davemloft.net>,
	Andrew Lunn <andrew+netdev@lunn.ch>,
	Eric Dumazet <edumazet@google.com>,
	Nicolai Buchwitz <nb@tipi-net.de>,
	Paolo Abeni <pabeni@redhat.com>,
	Ronald Wahl <ronald.wahl@raritan.com>,
	Yicong Hui <yiconghui@gmail.com>,
	linux-kernel@vger.kernel.org, Thomas Gleixner <tglx@kernel.org>
Subject: Re: [net,PATCH v2] net: ks8851: Reinstate disabling of BHs around IRQ handler
Date: Mon, 13 Apr 2026 18:10:00 +0200	[thread overview]
Message-ID: <20260413161000.P_SLxmZl@linutronix.de> (raw)
In-Reply-To: <20260413084445.59fe28d6@kernel.org>

On 2026-04-13 08:44:45 [-0700], Jakub Kicinski wrote:
> On Mon, 13 Apr 2026 14:57:44 +0200 Sebastian Andrzej Siewior wrote:
> > On 2026-04-12 10:51:25 [-0700], Jakub Kicinski wrote:
> > > > Does the backtrace make the problem clearer, with the annotation above ?  
> > > 
> > > Sebastian, do you have any recommendation here? tl;dr is that the driver does  
> > …
> > 
> > What about this:
> 
> Thanks for taking a look (according to you auto-reply immediately after
> a vacation ;))

;)

> TBH changing the driver feels like a workaround / invitation for a
> whack-a-mole game. I'd prefer to fix the skb allocation.

The problem is that _irq() implicitly disables bh processing but this
does not happen. Forcing this is possible but expensive.
However, I did remove lock from bh_disable() on RT.

Marek: from which kernel version was this backtrace?

> Is there any way we can check if any locks which were _irq() on non-RT
> are held?

lockdep has a list of locks which are acquired but it does not see if it
is _irq() or not. It only records it was acquired.

Sebastian

      reply	other threads:[~2026-04-13 16:10 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-04-08 16:24 [net,PATCH v2] net: ks8851: Reinstate disabling of BHs around IRQ handler Marek Vasut
2026-04-09  6:52 ` Nicolai Buchwitz
2026-04-09 15:26   ` Marek Vasut
2026-04-10  7:29     ` Nicolai Buchwitz
2026-04-12 16:01 ` Jakub Kicinski
2026-04-12 16:27   ` Marek Vasut
2026-04-12 17:51     ` Jakub Kicinski
2026-04-13 12:57       ` Sebastian Andrzej Siewior
2026-04-13 15:31         ` Marek Vasut
2026-04-13 16:03           ` Sebastian Andrzej Siewior
2026-04-13 15:44         ` Jakub Kicinski
2026-04-13 16:10           ` Sebastian Andrzej Siewior [this message]

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=20260413161000.P_SLxmZl@linutronix.de \
    --to=bigeasy@linutronix.de \
    --cc=andrew+netdev@lunn.ch \
    --cc=davem@davemloft.net \
    --cc=edumazet@google.com \
    --cc=kuba@kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=marex@nabladev.com \
    --cc=nb@tipi-net.de \
    --cc=netdev@vger.kernel.org \
    --cc=pabeni@redhat.com \
    --cc=ronald.wahl@raritan.com \
    --cc=stable@vger.kernel.org \
    --cc=tglx@kernel.org \
    --cc=yiconghui@gmail.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