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Date: Thu, 12 Nov 2026 14:44:34 +0100
From: Christoph Hellwig <hch@lst.de>
To: Hengyu Liang <hengyul@cs.unc.edu>
Cc: Carlos Maiolino <cem@kernel.org>, "Darrick J. Wong" <djwong@kernel.org>,
	Christoph Hellwig <hch@lst.de>, linux-xfs@vger.kernel.org,
	linux-kernel@vger.kernel.org, stable@vger.kernel.org
Subject: Re: [PATCH] xfs: fix f_bfree underflow in statfs()
Message-ID: <20261112134434.GA23459@lst.de>
References: <20261112102018.3922571-1-hengyul@cs.unc.edu>
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On Thu, Nov 12, 2026 at 05:20:18AM -0500, Hengyu Liang wrote:
> The issue can be reproduced on a new 2 GiB filesystem mounted on /mnt:
> 
>     for i in $(seq 3000); do head -c 65536 /dev/zero > /mnt/s$i; done
>     dd if=/dev/zero of=/mnt/big bs=1M
>     xfs_io -x -c 'resblks 100000000' /mnt
>     for i in $(seq 1 2 3000); do rm /mnt/s$i; done
>     sync
>     df -h /mnt

Can you add this to xfstests?

The fix itself looks good, thanks a lot!

Reviewed-by: Christoph Hellwig <hch@lst.de>