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Date: Tue, 5 Dec 2023 23:16:33 -0800
From: Christoph Hellwig <hch@infradead.org>
To: Eric Biggers <ebiggers@kernel.org>
Cc: Christoph Hellwig <hch@infradead.org>, linux-fscrypt@vger.kernel.org,
	linux-fsdevel@vger.kernel.org, linux-btrfs@vger.kernel.org,
	Josef Bacik <josef@toxicpanda.com>
Subject: Re: [PATCH] fscrypt: move the call to fscrypt_destroy_keyring() into
 ->put_super()
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References: <20231206001325.13676-1-ebiggers@kernel.org>
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On Tue, Dec 05, 2023 at 10:44:30PM -0800, Eric Biggers wrote:
> There are lots of filesystems that free their ->s_fs_info in ->put_super().  Are
> they all wrong?

Wrong is the wrong word :)

For simple file systems that either don't use block devices, or just
the main one set up by the super.c code using ->put_super is perfectly
fine.  Once a file system does something complicated like setting up
their own block devices, or trying to reuse super blocks using custom
rules it basically has to free ->s_fs_info  in it's own ->kill_sb
handler.  This whole area is a bit messy unfortunately.