Return-Path: Received: from mail-lj1-f194.google.com ([209.85.208.194]:37471 "EHLO mail-lj1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726193AbeLHV7L (ORCPT ); Sat, 8 Dec 2018 16:59:11 -0500 Received: by mail-lj1-f194.google.com with SMTP id e5-v6so6469851lja.4 for ; Sat, 08 Dec 2018 13:59:10 -0800 (PST) Received: from mail-lj1-f174.google.com (mail-lj1-f174.google.com. [209.85.208.174]) by smtp.gmail.com with ESMTPSA id c203sm1287720lfe.95.2018.12.08.13.59.07 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Sat, 08 Dec 2018 13:59:08 -0800 (PST) Received: by mail-lj1-f174.google.com with SMTP id u6-v6so6470439ljd.1 for ; Sat, 08 Dec 2018 13:59:07 -0800 (PST) MIME-Version: 1.0 References: <20181206230903.30011-1-krisman@collabora.com> <20181208194128.GE20708@thunk.org> In-Reply-To: From: Linus Torvalds Date: Sat, 8 Dec 2018 13:58:51 -0800 Message-ID: Subject: Re: [PATCH v4 00/23] Ext4 Encoding and Case-insensitive support To: "Theodore Ts'o" Cc: linux-fsdevel , kernel@collabora.com, linux-ext4@vger.kernel.org, krisman@collabora.com Content-Type: text/plain; charset="UTF-8" Sender: linux-ext4-owner@vger.kernel.org List-ID: On Sat, Dec 8, 2018 at 1:48 PM Linus Torvalds 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