From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mout.web.de (mout.web.de [212.227.15.4]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id DC6B13101D2 for ; Mon, 16 Feb 2026 13:43:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=212.227.15.4 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771249437; cv=none; b=eltxmSHjuXyLaRp6vzoR77zFoTqW8+UB6NARIun100TwmxUrx+kqn66eucXh7goMKxPpW7ja35lk390Knp6MNEcGxun0ttl3CcEAZaCuAo4n/uVo/9XiZ3hhUqee9lXQbfswKDajOiEjfAYLNVu67bIoUXhv+VR1+Hfo+DOAY+8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771249437; c=relaxed/simple; bh=cbfGdeTGS5fXk39OIwNWosl7v4mPCJc/RrIYmSbReso=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; 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kgucLGPezychDxGd1WRbIeC52DiYdJK9UZPWQdhL5ByrcryjQaFlR7c6K7EXkVHIn9Bu2nnLs xZAyy4lCymbyiyj+4= Starting with linux-6.18, I see the following log messages 2026-02-15T23:50:17.558716+01:00 [ T1559] Dead loop on virtual device wlp4s0, fix it urgently! 2026-02-15T23:50:17.558737+01:00 [ T1559] Dead loop on virtual device wlp4s0, fix it urgently! [...] regarding my wireless network device 04:00.0 Network controller [0280]: MEDIATEK Corp. MT7921K (RZ608) Wi-Fi 6E 80MHz [14c3:0608] I bisected this (from v6.17 to v6.18) and got this as the first bad commit: 3253cb49cbad ("softirq: Allow to drop the softirq-BKL lock on PREEMPT_RT") Using CONFIG_PREEMPT_RT_NEEDS_BH_LOCK=y in v6.18.10 fixes the issue. Bert Karwatzki