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Date: Thu, 6 Jun 2024 15:08:32 +0200
From: Christoph Hellwig <hch@lst.de>
To: Ofir Gal <ofir.gal@volumez.com>
Cc: Sagi Grimberg <sagi@grimberg.me>, Christoph Hellwig <hch@lst.de>,
	davem@davemloft.net, linux-block@vger.kernel.org,
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Subject: Re: [PATCH v2 1/4] net: introduce helper sendpages_ok()
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On Thu, Jun 06, 2024 at 03:57:25PM +0300, Ofir Gal wrote:
> The slab pages aren't allocated by the md-bitmap, they are pages that
> happens to be after the allocated pages. I'm applying a patch to the md
> subsystem asap.

Similar cases could happen by other means as well.  E.g. if you write
to the last blocks in an XFS allocation group while also writing something
to superblock copy at the beginnig of the next one and the two writes get
merged.  Probably not easy to reproduce but entirely possible.  Just as
as lot of other scenarious could happen due to merges.