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Date: Tue, 14 Jul 2026 07:20:11 +0200
From: Christoph Hellwig <hch@lst.de>
To: "Darrick J. Wong" <djwong@kernel.org>
Cc: Christoph Hellwig <hch@lst.de>, cem@kernel.org, stable@vger.kernel.org,
	linux-xfs@vger.kernel.org
Subject: Re: [PATCH 5/6] xfs: write the rg superblock when fixing it
Message-ID: <20260714052011.GA31796@lst.de>
References: <178346726054.1271589.14164163317011378817.stgit@frogsfrogsfrogs> <178346726193.1271589.8429966417697809477.stgit@frogsfrogsfrogs> <20260713064105.GA29416@lst.de> <20260713215857.GG7195@frogsfrogsfrogs>
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On Mon, Jul 13, 2026 at 02:58:57PM -0700, Darrick J. Wong wrote:
> Hrmm.  Right now both superblock scrubbers don't do much for group 0,
> because both buffers are pinned to the xfs_mount, so they assume that
> there's no need to check anything.  However, the ondisk super could have
> gotten corrupted (or blown away by fdisk), in which case an immediate
> crash could render the filesystem unmountable.
> 
> So, I could (a) teach the super scrubbers to read the primary / rt
> super; and (b) teach them both to log the superblock and bwrite it
> immediately to shorten the window in which this could happen.
> 
> What do you think?

I guess the only sensible time to scrub the sb would be early during
mount? 

> Also, this patch should be calling xfs_log_sb *after* xfs_trans_getsb,
> so I'll fix that for the repost.

Oops.