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From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Sun, 28 Apr 2024 11:50:14 -0700
Message-ID: <CAHk-=wj6HmDetTDhNNUNcAXZzmCv==oHk22_kVW4znfO-HuMnA@mail.gmail.com>
Subject: Re: [PATCH v3] tty: tty_io: remove hung_up_tty_fops
To: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>, Dmitry Vyukov <dvyukov@google.com>, 
	syzbot <syzbot+b7c3ba8cdc2f6cf83c21@syzkaller.appspotmail.com>, 
	linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com, 
	Nathan Chancellor <nathan@kernel.org>, Arnd Bergmann <arnd@kernel.org>, Al Viro <viro@zeniv.linux.org.uk>, 
	Jiri Slaby <jirislaby@kernel.org>
Content-Type: text/plain; charset="UTF-8"

On Sun, 28 Apr 2024 at 03:20, Tetsuo Handa
<penguin-kernel@i-love.sakura.ne.jp> wrote:
>
>
> If we keep the current model, WRITE_ONCE() is not sufficient.
>
> My understanding is that KCSAN's report like

I find it obnoxious that these are NOT REAL PROBLEMS.

It's KCSAN that is broken and doesn't allow us to just tell it to
sanely ignore things.

I don't want to add stupid and pointless annotations for a broken tooling.

Can you instead just ask the KCSAN people to have some mode where we
can annotate a pointer as a "use one or the other", and just shut that
thing up that way?

Because no, we're not adding some idiotic "f_op()" wrapper just to
shut KCSAN up about a non-issue.

                     Linus