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From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Sat, 8 Dec 2018 13:58:51 -0800
Message-ID: <CAHk-=wg9J+9H4kvzF0SmBP_CoSrBTxPc6xMRJKb3fDnOUs0DNw@mail.gmail.com>
Subject: Re: [PATCH v4 00/23] Ext4 Encoding and Case-insensitive support
To: "Theodore Ts'o" <tytso@mit.edu>
Cc: linux-fsdevel <linux-fsdevel@vger.kernel.org>,
        kernel@collabora.com, linux-ext4@vger.kernel.org,
        krisman@collabora.com
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On Sat, Dec 8, 2018 at 1:48 PM Linus Torvalds
<torvalds@linux-foundation.org> wrote:
>
> Yes, allowing concurrent use then generates whole new "interesting"
> questions, like "what happens if a case _sensitive_ user creates two
> files with names that are identical to a in-sensitive user", but they
> aren't necessarily any worse than the issues you face *not* allowing
> that.

I'm hoping you are at least doing it per-directory. That makes at
least the "oh, the whole filesystem needs to do this wrong" issue a
bit less bad.

Just looking at the shortlog you posted, my guess is that the ext4
patches didn't even get *that* right, though. That shortlog "encoding
information in superblock" implies this is the same kind of just
horribly bad mess that we've seen before.

I really despise every single case-sensitive filesystem I have ever
seen, exactly because nobody apparently spends even a minimal amount
of effort on getting any of the basics remotely right. Every single
case I've seen has been a huge nasty hack, with seriously bad
system-wide consequences.

                  Linus