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 F093C242D7F; Tue, 14 Apr 2026 01:01:00 +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=1776128461; cv=none; b=LuIq1ywsyLnlOSUUpAwiTgj1ODd6XqCIHQ2BcWmA2qAULGkw7ozZoXowRboomoIciYjdfTDxw4hn/DbmmkwfooYTAWt5f/vOkQi6wWqDgrKp0d29ZAuWtAI3u/Zr3gp9txopaz3GMZHlAUn/GEFoPpObE/DsUHQ1u/GtTgcPG14= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776128461; c=relaxed/simple; bh=BlKAU1Qs9rgI2Bqmfdqc8qzuGcapi4hy62HJFElwNlg=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=ZnWBkaXnOrCxoOh4CaF6h++ABn38B6wLjBIMul1RZj8sYH5gCTSGHXuvOG7Ia6sJY2Fun4+CSINfEBoTGUAgU/Bef9URAIIOY/WzFLgWgkYij4zTolIiXbqzSEyY/xpgjwc+7xuiPcoym8iyczvUlbDgMiL5K0vbcffefyAPS3U= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=ItZTVKbw; 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="ItZTVKbw" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D0219C2BCB4; Tue, 14 Apr 2026 01:01:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1776128460; bh=BlKAU1Qs9rgI2Bqmfdqc8qzuGcapi4hy62HJFElwNlg=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=ItZTVKbwDZepUnrt+HdE2B6u4vredkj5WGDCbKyOvS3ZcQ753b8bmPX9zt6bZqd30 RsKltzmIOFvE1T/nou2enuA+Lkb3suHuAu6H8K1j1alNq6r3aXOwzPhU+DUtHK+VQq nfx5yetcmtIxLAzO6DvvViiJHpnGUpWk4LUTv5coe+s9wxC2nJWNtzAMXKcUIyKwyX RVuJ5GUWz3wMSUUxlehkPmDfSkfDFLUoCpGO+or39QbJ5mTF0iQxPB3XCd5sQOzCrf 9loSVk4RqecCV77MEgU1YFcSnOkEa+czJfs0OxainfqAEswEOec4p92kzumNqdv6xY J2oluuY3sjyfg== Date: Mon, 13 Apr 2026 18:01:00 -0700 From: "Darrick J. Wong" To: Dave Chinner Cc: Yuto Ohnuki , Carlos Maiolino , linux-xfs@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v3 2/3] xfs: zero directory data block padding on write verification Message-ID: <20260414010100.GA150005@frogsfrogsfrogs> References: <20260411142411.72194-5-ytohnuki@amazon.com> <20260411142411.72194-7-ytohnuki@amazon.com> <20260413175921.GM1048989@frogsfrogsfrogs> Precedence: bulk X-Mailing-List: linux-xfs@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Tue, Apr 14, 2026 at 10:39:53AM +1000, Dave Chinner wrote: > On Mon, Apr 13, 2026 at 10:59:21AM -0700, Darrick J. Wong wrote: > > On Sat, Apr 11, 2026 at 03:24:14PM +0100, Yuto Ohnuki wrote: > > > Old kernels did not zero the pad field in xfs_dir3_data_hdr when > > > initializing directory data blocks, so existing filesystems may have > > > non-zero padding on disk. > > > > > > Zero the pad field in xfs_dir3_data_write_verify alongside the existing > > > LSN and checksum updates. The pad field is pure alignment padding with > > > no runtime meaning, so zeroing it during write verification is safe and > > > has no additional I/O cost. This lets filesystems gradually self-heal > > > stale non-zero padding as directories are modified, without requiring an > > > explicit repair pass. > > > > > > Suggested-by: Dave Chinner > > > Signed-off-by: Yuto Ohnuki > > > --- > > > fs/xfs/libxfs/xfs_dir2_data.c | 6 ++++++ > > > 1 file changed, 6 insertions(+) > > > > > > diff --git a/fs/xfs/libxfs/xfs_dir2_data.c b/fs/xfs/libxfs/xfs_dir2_data.c > > > index 35ff119aa84b..aecbab61014c 100644 > > > --- a/fs/xfs/libxfs/xfs_dir2_data.c > > > +++ b/fs/xfs/libxfs/xfs_dir2_data.c > > > @@ -382,6 +382,7 @@ xfs_dir3_data_write_verify( > > > struct xfs_mount *mp = bp->b_mount; > > > struct xfs_buf_log_item *bip = bp->b_log_item; > > > struct xfs_dir3_blk_hdr *hdr3 = bp->b_addr; > > > + struct xfs_dir3_data_hdr *datahdr3 = bp->b_addr; > > > xfs_failaddr_t fa; > > > > > > fa = xfs_dir3_data_verify(bp); > > > @@ -396,6 +397,11 @@ xfs_dir3_data_write_verify( > > > if (bip) > > > hdr3->lsn = cpu_to_be64(bip->bli_item.li_lsn); > > > > > > + /* > > > + * Zero padding that may be stale from old kernels. > > > + */ > > > + datahdr3->pad = 0; > > > > This needs to be gated on the directory block actually having a dir3 > > data header (aka xfs_has_crc()). > > It already is gated correctly - this check is done 5 lines above: > > if (!xfs_has_crc(mp)) > return; So it is. My bad; Reviewed-by: "Darrick J. Wong" --D > > -Dave. > > -- > Dave Chinner > dgc@kernel.org >