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 D60FE2A1CF for ; Wed, 18 Mar 2026 05:56:49 +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=1773813409; cv=none; b=XCLS+8/sdnnN4HvAnt7j8Au+UvrW8kBmaHrtVmnDntpKpURptUWj9EbmCryFDDxmXlwz71WIM+AQgfOm3rWNuNFwV+Vw/kI4cmyIV+ongWP1W7VO/P4fd8rd4a57pfE4sA7pppq8ByiWqT6MsfRKcYkqonZifOfVDhctQaSDb3Q= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773813409; c=relaxed/simple; bh=rfnoONL4n34OjU2sHTyixSXVbI/HvWxE4shOwhh1/U4=; h=Message-ID:Date:MIME-Version:Cc:Subject:To:References:From: In-Reply-To:Content-Type; b=S843JMeKrZu7FuEPpMHZdI89YwKXuq7P7b0xEwF6IDsnDr/JHuwIUmHCqhWVwOS5g1uoOk4ft1gwFyj1z/9Oa34Z77oPbm90L+l3D2LsKPSF+XAqkWz9qqTof9j6S5p/Mtb97L225ZEgvue/iWPhZN8ciAcATda/+uOjytGFYd8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=hLA071Zc; 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="hLA071Zc" Received: by smtp.kernel.org (Postfix) with ESMTPSA id CEA32C19421; Wed, 18 Mar 2026 05:56:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1773813409; bh=rfnoONL4n34OjU2sHTyixSXVbI/HvWxE4shOwhh1/U4=; h=Date:Cc:Subject:To:References:From:In-Reply-To:From; b=hLA071ZclBL3RTTcwn/pOIftcsRdkRLlQ01MypwCaaWnEpWDP+9OHf7TWsWz6B1Og 4Y/JQTzVhxygAasPS/tdwraK/zCHgOpskGJFXTXjK1NkLKlxZR6TVub1ozlWOOx8PM WEoZuDlah4w0rAwhw0WrmVh9p9x5lnVq4epGNeb9MbXzGAacNv4uAArXBj94NLbts1 oDxhH+8Tr6CNiRipMdPAbsJ80G6IxavymzuiwD9JLKvY54pAeSUm7hQKO2a6R7TD66 E/ZGJTFadHf6/b8nfweWHTrwS44a5Xp+LlVv0kFM0cHS1t4VuLJV8ZrgYAHeIOaYNS utARMWH6rdxaw== Message-ID: Date: Wed, 18 Mar 2026 13:56:42 +0800 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Cc: chao@kernel.org, linux-f2fs-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org, baijiaju1990@gmail.com, r33s3n6@gmail.com, gality369@gmail.com, zhenghaoran154@gmail.com, hanguidong02@gmail.com, ziyuzhang201@gmail.com Subject: Re: [PATCH] f2fs: add READ_ONCE() for i_blocks in f2fs_update_inode() To: Cen Zhang , jaegeuk@kernel.org References: <20260317114225.3017089-1-zzzccc427@gmail.com> Content-Language: en-US From: Chao Yu In-Reply-To: <20260317114225.3017089-1-zzzccc427@gmail.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 2026/3/17 19:42, Cen Zhang wrote: > f2fs_update_inode() reads inode->i_blocks without holding i_lock to > serialize it to the on-disk inode, while concurrent truncate or > allocation paths may modify i_blocks under i_lock. Since blkcnt_t is > u64, this risks torn reads on 32-bit architectures. > > Following the approach in ext4_inode_blocks_set(), add READ_ONCE() to prevent > potential compiler-induced tearing. > Need a Fixes line and Cc stable@kernel.org? Otherwise, it looks good to me. Thanks, > Signed-off-by: Cen Zhang > --- > fs/f2fs/inode.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/fs/f2fs/inode.c b/fs/f2fs/inode.c > index 078874db918c..73b913dbe02a 100644 > --- a/fs/f2fs/inode.c > +++ b/fs/f2fs/inode.c > @@ -694,7 +694,7 @@ void f2fs_update_inode(struct inode *inode, struct folio *node_folio) > ri->i_uid = cpu_to_le32(i_uid_read(inode)); > ri->i_gid = cpu_to_le32(i_gid_read(inode)); > ri->i_links = cpu_to_le32(inode->i_nlink); > - ri->i_blocks = cpu_to_le64(SECTOR_TO_BLOCK(inode->i_blocks) + 1); > + ri->i_blocks = cpu_to_le64(SECTOR_TO_BLOCK(READ_ONCE(inode->i_blocks)) + 1); > > if (!f2fs_is_atomic_file(inode) || > is_inode_flag_set(inode, FI_ATOMIC_COMMITTED))