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Date:   Wed, 04 Jan 2023 15:43:33 +0100
From:   "Arnd Bergmann" <arnd@arndb.de>
To:     syzbot <syzbot+7bb7cd3595533513a9e7@syzkaller.appspotmail.com>,
        "Andrew Morton" <akpm@linux-foundation.org>,
        christian.brauner@ubuntu.com,
        "Damien Le Moal" <damien.lemoal@opensource.wdc.com>,
        jlayton@kernel.org, linux-fsdevel@vger.kernel.org,
        linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com,
        "Linus Torvalds" <torvalds@linux-foundation.org>,
        "Matthew Wilcox" <willy@infradead.org>
Subject: Re: [syzbot] [hfs?] WARNING in hfs_write_inode
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On Wed, Jan 4, 2023, at 15:24, syzbot wrote:

> The issue was bisected to:
>
> commit 55d1cbbbb29e6656c662ee8f73ba1fc4777532eb
> Author: Arnd Bergmann <arnd@arndb.de>
> Date:   Tue Nov 9 02:35:04 2021 +0000
>
>     hfs/hfsplus: use WARN_ON for sanity check
>

My patch was a mechanical conversion from '/* panic? */'
to 'WARN_ON()' to work around a compiler warning,
and the previous code had been in there since the
2004 HFS rewrite by Roman Zippel.

I know nothing about what this function actually does,
so my best answer is that we could revert my patch
and use pr_debug() instead of WARN_ON() for all of these.

    Arnd