From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=74.208.142.49 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794474159; b=xkDKHdTH3nal6MUcqIaJ8BZ/+vtZsi0CNd+fS7m4SupK0FjOzcB5+g3PNlV2lGDWbdvN 5G3X7HDttKQQox7nodV9NCI9Z21phLlnPv32oHtjDTrPp02b6Ml0a5ubD3kRh9ehMb6XJ 1rZRi0pUcocPuVPi4UOYJ96sBoQ00gLTLPbMsmWZa8gyddz4MrbEf0dtp4cav6yVo+2Jw OtCXxFqq7OexJK0vPhq9F3G8KNz+f0LDq+XU2ikEoF7owVaksWYGjDayNZrVVzPNzEU2T l5RrmYKBqCa8WcYIsLh6VeQKBqfx//LP/caqdGNMJKDaCPR7EpVAE+tVWCeP33TmjzQ== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794474159; h=DMARC-Filter:DKIM-Signature:Received:From:To:Cc:Subject:Date: Message-ID:X-Mailer:In-Reply-To:References:MIME-Version: Content-Transfer-Encoding; bh=sQTROA+2ZM7HhctIX3ti/nZ/3akeIRzlGS88TA6PMJU=; b=gv5/i52WCVAlJsI6qMw8Ps6W0V7oHqqEBsY6KgB6zU/kCAyduwzEXUGsQ7yeqGA+Muu8 Tc2y5L2RL9YLCNTCIbne3QiF838y7owirl04umSAkxxKbXpkZacJnPzsVnljzvrvLs+Ue 72I8S+QvhcHXNCwdlRRoUyrpUkUKOYEY0igw7nErwsMJ78S0E1zhd5Xvrwa8RHDMseFEX B+3q1K3Z9gasd0QTRsbZY6hzlztgGFOxTxGkQ2CPmpVmfCWU+GvWu32xiNrodml6kqGhp RnI35Epsui12giG5HULp989udV8jIkHZayMDLzdP+DNqnLC/Mff+hPkVWVlqUasArEw== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=kernelriot.com; spf=pass smtp.mailfrom=kernelriot.com; dkim=pass header.d=kernelriot.com header.i=@kernelriot.com header.a=rsa-sha256 header.s=kr2026 header.b=isBuGvu9; arc=none smtp.remote-ip=74.208.142.49 Received: from mail.kernelriot.com (mail.kernelriot.com [74.208.142.49]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3FE4E606A335; Thu, 12 Nov 2026 09:02:39 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org 3FE4E606A335 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=kernelriot.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=kernelriot.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernelriot.com header.i=@kernelriot.com header.a=rsa-sha256 header.s=kr2026 header.b=isBuGvu9 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernelriot.com; s=kr2026; t=1794474152; bh=wsxfuSYTb4m26WLN6I++b1kztJk7XRmZPsgFbFQo/OM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Transfer-Encoding:From; b=isBuGvu9e9I43xxC5UdLS2Lhf+K/f44bWFDXYcogt925ZxnGaolkCvK/lu/RgHAzK 0DbXDhs52zZgSbY/o0TVj7MyMO4gb6zN0dslZc+d1gyZB0ey1jVBWKHFCjZk6RIzDC kpwzfwn1tK9S2rbjOi64/G36UIE/G9UB5K3IkDwwCsXm1i/QWdCtJJOUk9fAhzoUGF biNpGRlulV7e6IJjQrEBbFzKZQ7tQq5cUDUZWQJOZjVts2tUuDn/euZ5I/NOsmvEJD +gqtolF/KGpsUDNs6Q1frvMXpa+m9ZhRmpuElB8GOQNYK+0w1ptOyjcwr4zSgYKb9w y/so5aOT7RoOg== Received: by mail.kernelriot.com (Postfix, from userid 995) id 1218081A15; Thu, 12 Nov 2026 09:02:32 +0000 (UTC) From: Magnus Leatti To: syzbot+3e3c2f8ca188e30b1427@syzkaller.appspotmail.com Cc: syzkaller-bugs@googlegroups.com, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, oe-linux-nfc@lists.linux.dev, David Heidelberg , Johannes Berg , Deepanshu Kartikey Subject: Re: [syzbot] INFO: task hung in nfc_rfkill_set_block Date: Thu, 12 Nov 2026 06:02:17 -0300 Message-ID: <20261112090217.1462672-1-magnusleatti@kernelriot.com> X-Mailer: git-send-email 2.56.0 In-Reply-To: <000000000000959f6b05ed853d12@google.com> References: <000000000000959f6b05ed853d12@google.com> X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Hi, This looks like the device_lock vs rfkill_global_mutex inversion fixed by 1ab526d97a57 ("net: nfc: fix deadlock between nfc_unregister_device and rfkill_fop_write"). That fix credited a different syzbot report, so this one was never linked to it. I ran the C reproducer for 600 s per kernel, x86_64 under QEMU/KVM: 1ab526d97a57^ hung task report at 91 s (rfkill_sync_work in nfc_dev_down, nfc_unregister_device in rfkill_unregister) 1ab526d97a57 no hang 9d66f26fefac no hang (mainline) #syz fix: net: nfc: fix deadlock between nfc_unregister_device and rfkill_fop_write Thanks, Magnus