From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from relay.yourmailgateway.de (relay.yourmailgateway.de [188.68.61.103]) (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 548F94FC343; Fri, 18 Sep 2026 13:38:46 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=188.68.61.103 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789738729; cv=none; b=M6gLXBY5z+7OKNU9k02rFj1DemKLqN2KZ8mX0SZ0ZBIjk2Nubc0xrpL8zMFnRgI2sQAQ7NtnLEYla1wwSLQyWRQcpdRo/xCWg+uoTHPPIUHIXv720KhTaH6J8D673U3H5GWJpaaX5CTRU3aPy4KTVfulcJ+vpXGPPr7qa8WbQQk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789738729; c=relaxed/simple; bh=NSGPR63vm0J21dwn5r1enKuzdn3dCG4YKJPLYpM64W8=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=pFoP2V7uLvvNlseT7j68T+ECogibR/n5gY5Ji9HoR+/VZJLmbzfZY+IBGvXkeMtjvsQRlGgnmH+0PQBXjQGKQKkU0ChJIbaqdZjqL+lWmR8rFSJ0iHlGfwSs+it5/gOWmeNaZueefq1qazpKR6O6cCY+wRu3Vsz3Dok0+9Z5nDI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=leemhuis.info; spf=pass smtp.mailfrom=leemhuis.info; dkim=pass (2048-bit key) header.d=leemhuis.info header.i=@leemhuis.info header.b=HW+OE7NR; arc=none smtp.client-ip=188.68.61.103 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=leemhuis.info Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=leemhuis.info Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=leemhuis.info header.i=@leemhuis.info header.b="HW+OE7NR" Received: from mors-relay-8403.netcup.net (localhost [127.0.0.1]) by mors-relay-8403.netcup.net (Postfix) with ESMTPS id 4hmYcN1gwTz87cq; Fri, 18 Sep 2026 15:38:44 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=leemhuis.info; s=key2; t=1789738724; bh=NSGPR63vm0J21dwn5r1enKuzdn3dCG4YKJPLYpM64W8=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=HW+OE7NRUKVex6wzHEF3IQTF86Pm+OWJotfW/8EBhztiEcpPSe0QZnBjVbXTtdl60 BWd9B/DO/3HiiCAI4dB/LGmJEPmSVb3f46lkkj0u0dbLZxY5kBBcFhRZWC/fSoqLtD ylHfmj2tlAQUjwRWp229sCJ/47+p2NR38zKOFv07cH+WKFvJBB2RrlERKJw9s7JIVC vZo2ijWwyMzYHu/6u/Q9/Qws+KnYzi485QNnv9H30juGLbOt7JEVa3x53ZFNV1pCZj O9iWgt3P6eV0XUc7C05InzdA+9M7MVUnF6Jov/6fm1pcQvpNtnShLnKE2sj5F1KhhL hQq37qPtD9qaw== Received: from policy02-mors.netcup.net (unknown [46.38.225.35]) by mors-relay-8403.netcup.net (Postfix) with ESMTPS id 4hmYb34b8Jz8DFZ; Fri, 18 Sep 2026 15:37:35 +0200 (CEST) Received: from mxe9fb.netcup.net (unknown [10.243.12.53]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-256) server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by policy02-mors.netcup.net (Postfix) with ESMTPS id 4hmYb243hHz8sZP; Fri, 18 Sep 2026 15:37:34 +0200 (CEST) Received: from [IPV6:2a02:8108:8984:1d00:a0cf:1912:4be:477f] (unknown [IPv6:2a02:8108:8984:1d00:a0cf:1912:4be:477f]) by mxe9fb.netcup.net (Postfix) with ESMTPSA id CAC7F5FA16; Fri, 18 Sep 2026 15:37:33 +0200 (CEST) Authentication-Results: mxe9fb; spf=pass (sender IP is 2a02:8108:8984:1d00:a0cf:1912:4be:477f) smtp.mailfrom=regressions@leemhuis.info smtp.helo=[IPV6:2a02:8108:8984:1d00:a0cf:1912:4be:477f] Received-SPF: pass (mxe9fb: connection is authenticated) Message-ID: Date: Fri, 18 Sep 2026 15:37:32 +0200 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [REGRESSION] RTL8761BU 0bda:a728: removing BROKEN_EXT_SCAN fixes 0x200c timeout To: Andy Tsvetinskiy Cc: regressions@lists.linux.dev, linux-bluetooth@vger.kernel.org, Kamil Serwus , Junjie Cao , Luiz Augusto von Dentz , Marcel Holtmann , LKML , Alexej Sidorenko References: From: Thorsten Leemhuis Content-Language: de-DE, en-US In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-PPP-Message-ID: <178973865431.1866550.16469531839496829366@mxe9fb.netcup.net> X-NC-CID: bpcrAflHt8zdY5QrWqS0S4zUNqIX10pwqepvi9WfE/OjxMyZz1A= Lo! On 9/18/26 11:21, Andy Tsvetinskiy wrote: > > This report concerns USB ID 0bda:a728, not 0bda:8771. > > I have a Realtek RTL8761BUV USB Bluetooth adapter: > > - USB ID: 0bda:a728 > - Product: Bluetooth 5.4 Radio > - Firmware: rtl_bt/rtl8761bu_fw.bin > - Firmware version: 0xdfc6d922 > - Running kernel: 6.18.51-1-lts > - Distribution: Arch Linux > > With the stock btusb driver, Bluetooth repeatedly failed with: > > Bluetooth: hci0: command 0x200c tx timeout > Bluetooth: hci0: Opcode 0x200c failed: -110 > Bluetooth: hci0: Unable to disable scanning: -110 > Bluetooth: hci0: Resetting usb device. > usb 1-2.2: reset full-speed USB device > Bluetooth: hci0: unexpected event for opcode 0x200c Thx for the report. Just replying to bring a few people into the loop that can help handling this: the Blutooth maintainers and developers which were involved in ca0583c2466174 ("Bluetooth: btusb: limit RTL8761B BROKEN_EXT_SCAN quirk to 0bda:a728") [v7.3-rc1] and 5ead2063611ae5 ("Bluetooth: btrtl: fix RTL8761B/BU broken LE extended scan") [v7.2-rc1]. Ciao, Thorsten > The firmware was loaded successfully: > > Bluetooth: hci0: RTL: loading rtl_bt/rtl8761bu_fw.bin > Bluetooth: hci0: RTL: loading rtl_bt/rtl8761bu_config.bin > Bluetooth: hci0: RTL: fw version 0xdfc6d922 > > The USB autosuspend setting was not the cause: > > /sys/bus/usb/devices/1-2.2/power/autosuspend: -1 > > The current upstream fix ca0583c24661 > ("Bluetooth: btusb: limit RTL8761B BROKEN_EXT_SCAN quirk to 0bda:a728") > is already present in my kernel. It sets BTUSB_BROKEN_EXT_SCAN for 0bda:a728. > > I tested the opposite change locally in drivers/bluetooth/btusb.c: > > - { USB_DEVICE(0x0bda, 0xa728), .driver_info = BTUSB_REALTEK | > - BTUSB_BROKEN_EXT_SCAN }, > + { USB_DEVICE(0x0bda, 0xa728), .driver_info = BTUSB_REALTEK }, > > After rebuilding and reloading the btusb module: > > systemctl stop bluetooth > modprobe -r btusb > modprobe btusb > systemctl start bluetooth > > Bluetooth scanning worked normally. A 20-second scan completed with: > > Discovery started > Discovering: yes > > After loading the patched module, no new occurrences of the > following messages appeared: > > Opcode 0x200c failed: -110 > Opcode 0x2042 failed > command tx timeout > Unable to disable scanning > Resetting usb device > > The patched driver is currently loaded and Bluetooth remains operational. > > This suggests that different RTL8761BUV devices or firmware > revisions using USB ID 0bda:a728 may require different scan quirks. On > my device, keeping BTUSB_BROKEN_EXT_SCAN causes the legacy 0x200c > command to > time out, while removing the quirk fixes the issue. > > Relevant upstream reports: > > https://linux-regtracking.leemhuis.info/regzbot/regression/lore/20260822141115.58815-1-kserwus@gmail.com/ > > https://bugzilla.redhat.com/show_bug.cgi?id=2521504 > > https://lkml.iu.edu/2608.2/12212.html > > Please let me know if more logs, a full patch, or additional > testing is needed. >