From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 236082040B6; Tue, 3 Jun 2025 13:43:12 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1748958193; cv=none; b=N8IKI3Q7V8H9iA83mAtb0YsI+5iH+DfyMBdbXs8+/9341M7cFwYgX27q2obfhdKrZfUnC/fShgaxfr2k29M681eGOc+Q5jUaO6uXd+zpGiXvwss9Cu6Ex3pz40UQTOtJEu4khdmeV08exaXS0FaD2AyQtxTD9VmfqfqGzybEXrw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1748958193; c=relaxed/simple; bh=f0Vts21CODFgvUIe6d7miDR1R94z5uujshns22T5DEI=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=NQPziMzcyvQb305locu05MkyiJgj8l4b+OFkF4CpisyucJsMAErxvkTT4zp0OTyQxvqXBtBUnWIjPNYjmfmq2FKAmwwm9/OpTpW04XfmnEULSrD0cTTimnFqdRfFw2tU/NeOJupvKDHpUHd0pjSMVNDt2Dxwqs4+D7jSgEt7l70= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=dTrW3brN; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="dTrW3brN" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 20277C4CEED; Tue, 3 Jun 2025 13:43:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1748958192; bh=f0Vts21CODFgvUIe6d7miDR1R94z5uujshns22T5DEI=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=dTrW3brNAI40yQ+lEJJtV1PRO+6XB7A++lkDT8TKFAkaWimNeZRoOak2au8RDl9jA waUdu1K+xPDBKrH/HEIWTrO63K4Y6GPstVfSW2gtMBTAYmIGgliSSfUS4QGp6Pno/i MfmXkcYstcIYzqN+Hpg4EUiRu1E5i4KEOmClvnZzNgQk/NUlL5GDSGoPc9kzzwCvE0 RQ9t3veMWZ8VCNmyUkq1YYdukmqbRbuSop0EXD4QRz9GwvZpjccBp941Q/wFrwgtNz 8/kDyMQ9bMn2Hv2dPwGHKMZJydmduDUimlUygi9Ik0TI/8wtBCznxBl564wusPIU+x gntJdxl36jx8Q== Message-ID: <2a5432be-41b7-4adc-b68a-1f706036a59f@kernel.org> Date: Tue, 3 Jun 2025 15:43:09 +0200 Precedence: bulk X-Mailing-List: linux-serial@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2 2/2] tty: Fix race against tty_open() in tty_register_device_attr() To: Max Staudt , =?UTF-8?Q?Ilpo_J=C3=A4rvinen?= Cc: Greg Kroah-Hartman , Johan Hovold , linux-serial , LKML , stable@vger.kernel.org References: <20250528132816.11433-1-max@enpas.org> <20250528132816.11433-2-max@enpas.org> <6068387e-7064-0c2b-700a-3817bea1045b@linux.intel.com> <16cc8c9d-f89a-406c-9427-94ca75984752@enpas.org> Content-Language: en-US From: Jiri Slaby Autocrypt: addr=jirislaby@kernel.org; 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charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit On 02. 06. 25, 15:40, Max Staudt wrote: > On 6/2/25 19:31, Ilpo Järvinen wrote: >>> +    mutex_lock(&tty_mutex); >> >> Use guard() so you don't need to change the returns and rollback path. > > Thanks, I didn't know about this new kind of helper. > > I'll leave it up to the TTY maintainers - if they don't express a > preference for guard(), I prefer guard(). Actually, I have a patchset to add a support for guard() for uart_lock and console_lock too and use it all over (incl. __free). They untangle the code on many places and get rid of much unneeded churn. But in this very case, I see there is a label, I am not sure if it works right here. Try compiling with clang -- it will tell you. You likely won't cross the label with the guard(). thanks, -- js suse labs