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Date:   Fri, 28 Apr 2023 18:11:45 +0100
From:   Al Viro <viro@zeniv.linux.org.uk>
To:     Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Cc:     Nathan Chancellor <nathan@kernel.org>,
        Jiri Slaby <jirislaby@kernel.org>,
        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
Subject: Re: [PATCH] tty: tty_io: remove hung_up_tty_fops
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On Sat, Apr 29, 2023 at 01:41:02AM +0900, Tetsuo Handa wrote:
> On 2023/04/29 1:27, Nathan Chancellor wrote:
> > I see this change has shown up in -next as commit 4c87e9e5479b ("tty:
> > tty_io: remove hung_up_tty_fops"), where it causes the following warning
> > for configurations without CONFIG_COMPAT (I used ARCH=arm defconfig):
> > 
> >   drivers/tty/tty_io.c:446:13: warning: 'hung_up_tty_compat_ioctl' defined but not used [-Wunused-function]
> >     446 | static long hung_up_tty_compat_ioctl(struct file *file,
> >         |             ^~~~~~~~~~~~~~~~~~~~~~~~
> > 
> > I am not sure if you just added that patch for additional test coverage
> > or for final acceptance but the following diff resolves this warning for
> > me, perhaps it can be folded in for a v2?
> 
> Thank you for reporting. Yes, moving the definition will solve the warning.

	IDGI...  Why do you need to keep that function at all?  Compare it
with hung_up_tty_ioctl() - they are token-for-token identical; the only
difference is the function name...