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From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
To: Yunseong Kim <ysk@kzalloc.com>
Cc: Johannes Berg <johannes.berg@intel.com>,
	Clark Williams <clrkwllms@kernel.org>,
	Steven Rostedt <rostedt@goodmis.org>, Jiri Kosina <jkosina@suse.cz>,
	Aaron Hill <aa1ronham@gmail.com>,
	Lukas Redlinger <rel+kernel@agilox.net>,
	Oleksii Shevchuk <alxchk@gmail.com>,
	Toke =?utf-8?Q?H=C3=B8iland-J=C3=B8rgensen?= <toke@redhat.com>,
	linux-wireless@vger.kernel.org, linux-rt-devel@lists.linux.dev,
	LKML <linux-kernel@vger.kernel.org>
Subject: Re: [RFC] mac80211: Potential sleep in atomic context in
 __ieee80211_wake_txqs
Message-ID: <20250819101004.KB4KbEO-@linutronix.de>
References: <c15a819a-51de-467c-93fd-c321dd2e8ec9@kzalloc.com>
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In-Reply-To: <c15a819a-51de-467c-93fd-c321dd2e8ec9@kzalloc.com>

On 2025-08-19 01:56:00 [+0900], Yunseong Kim wrote:
> Hi,
Hi,

> I found a potential PREEMPT_RT issue I noticed in __ieee80211_wake_txqs()
> 
>  static void __ieee80211_wake_txqs(struct ieee80211_sub_if_data *sdata, int ac)
>  {
>      ...
>      local_bh_disable();
>      spin_lock(&fq->lock);
>      ...
>  }
> 
> This sequence of local_bh_disable() followed by spin_lock(). On an 

As explained in the previous mail regarding for
inet_twsk_hashdance_schedule(), this is fine.

> Best regards,
> Yunseong Kim

Sebastian