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Andrzej Siewior Cc: Thomas Gleixner , linux-kernel@vger.kernel.org, linux-rt-devel@lists.linux.dev, spasswolf@web.de Date: Mon, 16 Feb 2026 16:32:29 +0100 In-Reply-To: <20260216134333.412332-1-spasswolf@web.de> References: <20260216134333.412332-1-spasswolf@web.de> Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.56.2-0+deb13u1 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Provags-ID: V03:K1:NGSjNYTRQi40X4Iy4radXeQkF69kEAFwvpMI433j+tu2LwY3gye 54GEXyHsS81OibqGBfBtFElK2e/eND7MXdVweEBAVor6y9/B9Fd2nU9pC3QWl77g5ccefpc aYgq8RiZyC0qgZ7PlwJwca8FrcX8aovDK43LT7ZGvbfRKGmxVS7cqmmhr3kr2A5Uged1STA r4+OzEpMXNeME4IGUh+PQ== X-Spam-Flag: NO UI-OutboundReport: notjunk:1;M01:P0:W+4414mBnlA=;Si6WO5Y7qUf9W+dnwxzZufSvLYL B2N3b7fxT27iEimg4gU9sDhyr5DgL7rQhxOKztqKTfu0PrFgI1QqoImixz78evTRrumlsg1BS clFNiqgACo7bsxEg/bLomZbgAH5TcVe/4El3BIBy3gxh9tb3AVj2APFYCTLZdAwzU5ayMqGP6 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eyxYpAp2QxhNnZBcYoLrlv03CGtL66V9YDH7Q2nki+hhJhq7T31S0EMwojf9TZzfqq7RhWjkn YCHUCdT4OUHn+uc1esHjQhcV7B9Qfk+JnWvl97geXm2JvmJddh9LeUJ+uoL4eCQ/geI53+UzT BJEqSgIdR1Fxm2sxAdVo96s8UDiqTM/KOZSzZpwBtMuISCYCZYSYc8gG7I7ujqSfhlYoi6iF1 z80wor2pqmhiZrth43b26nKAVIdeJt1mEP1aCFqhUplQUg+aP3bkUfWZE/XPAKmYezpKIT4ll PlkhgJybPDutaJNVuzIjbbA9QPb6VVO2I0lVwsIUdmzzPLpfh4Bm5djebYqA== Am Montag, dem 16.02.2026 um 14:43 +0100 schrieb Bert Karwatzki: > Starting with linux-6.18, I see the following log messages >=20 > 2026-02-15T23:50:17.558716+01:00 [ T1559] Dead loop on virtual device wl= p4s0, fix it urgently! > 2026-02-15T23:50:17.558737+01:00 [ T1559] Dead loop on virtual device wl= p4s0, fix it urgently! > [...] >=20 > regarding my wireless network device >=20 > 04:00.0 Network controller [0280]: MEDIATEK Corp. MT7921K (RZ608) Wi-Fi = 6E 80MHz [14c3:0608] >=20 > I bisected this (from v6.17 to v6.18) and got this as the first bad comm= it: > 3253cb49cbad ("softirq: Allow to drop the softirq-BKL lock on PREEMPT_RT= ") >=20 > Using CONFIG_PREEMPT_RT_NEEDS_BH_LOCK=3Dy in v6.18.10 fixes the issue. >=20 > Bert Karwatzki May I presume that to fix this properly at least some of the spin_lock_bh(= )s in net/mac80211/ need to be converted to local_lock_nested_bh()s? Bert Karwatzki