public inbox for stable@vger.kernel.org
 help / color / mirror / Atom feed
From: Jakub Kicinski <kuba@kernel.org>
To: Siddharth Vadapalli <s-vadapalli@ti.com>
Cc: <andrew+netdev@lunn.ch>, <davem@davemloft.net>,
	<edumazet@google.com>, <pabeni@redhat.com>, <danishanwar@ti.com>,
	<rogerq@kernel.org>, <horms@kernel.org>, <mwalle@kernel.org>,
	<nm@ti.com>, <v-singh1@ti.com>, <vadim.fedorenko@linux.dev>,
	<matthias.schiffer@ew.tq-group.com>, <vigneshr@ti.com>,
	<m-malladi@ti.com>, <jacob.e.keller@intel.com>,
	<stable@vger.kernel.org>, <netdev@vger.kernel.org>,
	<linux-kernel@vger.kernel.org>,
	<linux-arm-kernel@lists.infradead.org>, <srk@ti.com>
Subject: Re: [PATCH net 2/3] net: ethernet: ti: icssg_common: set irq_disabled after disabling TX IRQ
Date: Mon, 23 Feb 2026 18:48:40 -0800	[thread overview]
Message-ID: <20260223184840.06069afa@kernel.org> (raw)
In-Reply-To: <20260220041431.372610-3-s-vadapalli@ti.com>

On Fri, 20 Feb 2026 09:41:58 +0530 Siddharth Vadapalli wrote:
> The 'irq_disabled' variable indicates the current state of the TX IRQ and
> is used by the TX NAPI handler to determine whether the IRQ should be
> enabled.
> 
> Currently, 'irq_disabled' is set before actually disabling the IRQ by
> invoking disable_irq_nosync(). In an SMP environment, this leads to a race
> condition wherein the processor taking the interrupt sets 'irq_disabled'
> while another processor executing a previous instance of the TX NAPI
> handler sees 'irq_disabled' set and invokes enable_irq() before the TX IRQ
> is actually disabled by disable_irq_nosync(). This results in the following
> warning:
> 	Unbalanced enable for IRQ ...

AFAICT the flow on the Tx bug is not buggy, owner ship of the IRQ
vector passes handler -> NAPI -> timer. I don't see how those can
race.
-- 
pw-bot: cr

  reply	other threads:[~2026-02-24  2:48 UTC|newest]

Thread overview: 16+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-02-20  4:11 [PATCH net 0/3] Fix Unbalanced IRQ Enable for CPSW and ICSSG Siddharth Vadapalli
2026-02-20  4:11 ` [PATCH net 1/3] net: ethernet: ti: am65-cpsw-nuss: set irq_disabled after disabling RX IRQ Siddharth Vadapalli
2026-02-24  2:48   ` Jakub Kicinski
2026-02-24  5:10     ` Siddharth Vadapalli
2026-02-24 23:54       ` Jakub Kicinski
2026-02-25 11:12         ` Siddharth Vadapalli
2026-02-20  4:11 ` [PATCH net 2/3] net: ethernet: ti: icssg_common: set irq_disabled after disabling TX IRQ Siddharth Vadapalli
2026-02-24  2:48   ` Jakub Kicinski [this message]
2026-02-24 12:24     ` Siddharth Vadapalli
2026-02-24 23:49       ` Jakub Kicinski
2026-02-25 11:31         ` Siddharth Vadapalli
2026-02-26  0:09           ` Jakub Kicinski
2026-02-26 11:34             ` Siddharth Vadapalli
2026-02-20  4:11 ` [PATCH net 3/3] net: ethernet: ti: icssg_common: set irq_disabled after disabling RX IRQ Siddharth Vadapalli
2026-02-20 10:00 ` [PATCH net 0/3] Fix Unbalanced IRQ Enable for CPSW and ICSSG Malladi, Meghana
2026-02-23 17:39 ` Simon Horman

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=20260223184840.06069afa@kernel.org \
    --to=kuba@kernel.org \
    --cc=andrew+netdev@lunn.ch \
    --cc=danishanwar@ti.com \
    --cc=davem@davemloft.net \
    --cc=edumazet@google.com \
    --cc=horms@kernel.org \
    --cc=jacob.e.keller@intel.com \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=m-malladi@ti.com \
    --cc=matthias.schiffer@ew.tq-group.com \
    --cc=mwalle@kernel.org \
    --cc=netdev@vger.kernel.org \
    --cc=nm@ti.com \
    --cc=pabeni@redhat.com \
    --cc=rogerq@kernel.org \
    --cc=s-vadapalli@ti.com \
    --cc=srk@ti.com \
    --cc=stable@vger.kernel.org \
    --cc=v-singh1@ti.com \
    --cc=vadim.fedorenko@linux.dev \
    --cc=vigneshr@ti.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