From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1792487629; b=oTLRY0eWUxsdHvW0Kc9V35f+FdJMyK3P7sTcRQoR38u6PzDYrgJbolAxEtQVD5Dz1Web 2c2BBjjBeV+nT078ZeowZjzpypBPCWHGhjwPM5tJcEhYzPy63TUCmdY1PnppJIMSYAwVt EHBJFdh4lpT8d3lCImOHhbLBehnaEpRZ1vU1BZoDm1ZEC9aRlY8mRjYOjjmd9fenjHJBJ /GZD65kOXn/+mFooUJbhZgH20oNdcO5jJdcu/LE13cjVTFka5mUdebnE+35hJ9E3SMk/o avRBduRmmSoJFVbzyu2aAO1JgWzi2ycGOgUpfLlVpryGACDzPdO5stLUucTT1FmXhTA== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1792487629; h=Received:DKIM-Signature:Message-ID:Date:MIME-Version:User-Agent:Cc: Subject:To:References:Content-Language:From:In-Reply-To:Content-Type: Content-Transfer-Encoding; bh=cBT5Tv/OCYXZ5REQMB2nW+cv403IPsf1vrinm69NgC0=; b=A59emmVB7emtMmFog9duSi5iPG82bJLzuv1ySZ3PuVhKVGz/rXBwKuLQiYOt3LcgLTER h6tJc/ygDyNLACu0wQaW6chcT7WnF+it6mniPnBv9VyMpcSG376R4kfmB2IpvxTm6Y6uT vyryEDY7amNYG1+mEf6H761jn8hgVSu+rEifveXpef8ekj22qXga7FiKiIDKuGHHsyQ6U JwNU/7EpPudXvsyvuFdHGPLlF/pmlGL5JSf7gLgCf0oGK/UD9NkEEHZ/lem1ZmpvmAj0E MdnJ9bQ1JnSRvDe9O4orENNkh/w+PDA0l+G9ops5ks+ZHtCOnfailgCLkVe3Og0QWbg== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=QLnBLVxy; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 47261606A319; Tue, 20 Oct 2026 09:13:48 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=QLnBLVxy Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7BD2A1F000C4; Tue, 20 Oct 2026 09:13:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1792487628; bh=cBT5Tv/OCYXZ5REQMB2nW+cv403IPsf1vrinm69NgC0=; h=Date:Cc:Subject:To:References:From:In-Reply-To; b=QLnBLVxy/rzkLd0FngifJtK1Tqe/bFoag34nXhw4wCLaJc44NxrGppj//PRtUy1/H y8AGW4q+q21yxVYvn8qpW0WcF8/Tc/ZRXps1P0278s/P0joZD4DcN+//jHC6ns0njD qq8O2Lz9kyaGWPvJY2gMEp7kJ29YG6fJxgpv4pf4WR23NCemQ/TQszc7f6Vl1ETxoe HS1YVWYsfA/G4Imd7LCKVwyzSum8U29rrhG4ePfRfhd6YUNAi9GXM8qhSFzdlUmkR5 hVlp90x8/jJvzbiuya5Zko1k7XJZB48thL3G9EOk2CIH6tVHvNHjRnBMQNk9wPWqwC Dj5QDRHQfWhdg== Message-ID: <5c97f2ab-0fdb-4f87-898a-0f43ef42f470@kernel.org> Date: Tue, 20 Oct 2026 17:13:45 +0800 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 User-Agent: Mozilla Thunderbird Cc: chao@kernel.org, Daeho Jeong , stable@vger.kernel.org Subject: Re: [f2fs-dev] [PATCH] f2fs: expose resizable_tail feature via sysfs To: Daeho Jeong , linux-kernel@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net, kernel-team@android.com References: <20261014152138.138281-1-daeho43@gmail.com> Content-Language: en-US From: Chao Yu In-Reply-To: <20261014152138.138281-1-daeho43@gmail.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 10/14/26 23:21, Daeho Jeong wrote: > From: Daeho Jeong > > Userspace has no way to know whether the kernel supports the > resizable_tail_secno mount option before mounting. Passing it to a > kernel without the support fails the mount with -EINVAL, and checking > /sys/fs/f2fs//pinned_area_max_secno requires an f2fs instance > to be mounted already. > > Export /sys/fs/f2fs/features/resizable_tail so that userspace can check > the support before formatting or mounting a filesystem that relies on > resizable_tail_secno, e.g. a filesystem whose tail is going to be shrunk > online later. > > Fixes: c966d29e01bb ("f2fs: support resizable tail section and unify pinned allocation") > Cc: stable@vger.kernel.org > Signed-off-by: Daeho Jeong Reviewed-by: Chao Yu Thanks,