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Date:   Thu, 31 Aug 2023 07:25:29 +0100
From:   Al Viro <viro@zeniv.linux.org.uk>
To:     Christoph Hellwig <hch@lst.de>
Cc:     Christian Brauner <brauner@kernel.org>,
        Heiko Carstens <hca@linux.ibm.com>,
        Vasily Gorbik <gor@linux.ibm.com>,
        Alexander Gordeev <agordeev@linux.ibm.com>,
        Paul Moore <paul@paul-moore.com>,
        Stephen Smalley <stephen.smalley.work@gmail.com>,
        Eric Paris <eparis@parisplace.org>, linux-s390@vger.kernel.org,
        linux-fsdevel@vger.kernel.org, selinux@vger.kernel.org
Subject: Re: [PATCH 1/4] ramfs: free sb->s_fs_info after shutting down the
 super block
Message-ID: <20230831062529.GD3390869@ZenIV>
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 <20230831053157.256319-2-hch@lst.de>
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On Thu, Aug 31, 2023 at 07:31:54AM +0200, Christoph Hellwig wrote:
> sb->s_fs_info can only be safely freed after generic_shutdown_super was
> called and all access to the super_block has stopped.
> 
> Thus only free the private data after calling kill_litter_super, which
> calls generic_shutdown_super internally.

Take a look at what ramfs uses that thing for.  Remount and ->show_options().
Neither is an issue in ->kill_sb().  I don't really hate that patch, but
commit message is flat-out incorrect in this case.