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From:   Linus Torvalds <torvalds@linux-foundation.org>
Date:   Mon, 29 Aug 2022 10:19:36 -0700
Message-ID: <CAHk-=whScqgJaP71QBBS9ik0kUrZBDLw+ZvzF4AxEo7eviGwaw@mail.gmail.com>
Subject: Re: [PATCH RFC 1/2] coding-style.rst: document BUG() and WARN() rules
 ("do not crash the kernel")
To:     John Hubbard <jhubbard@nvidia.com>
Cc:     Dave Young <dyoung@redhat.com>,
        David Hildenbrand <david@redhat.com>,
        linux-kernel@vger.kernel.org, linux-mm@kvack.org,
        linux-doc@vger.kernel.org, kexec@lists.infradead.org,
        Andrew Morton <akpm@linux-foundation.org>,
        Ingo Molnar <mingo@kernel.org>,
        David Laight <David.Laight@aculab.com>,
        Jonathan Corbet <corbet@lwn.net>,
        Andy Whitcroft <apw@canonical.com>,
        Joe Perches <joe@perches.com>,
        Dwaipayan Ray <dwaipayanray1@gmail.com>,
        Lukas Bulwahn <lukas.bulwahn@gmail.com>,
        Baoquan He <bhe@redhat.com>, Vivek Goyal <vgoyal@redhat.com>,
        Stephen Johnston <sjohnsto@redhat.com>,
        Prarit Bhargava <prarit@redhat.com>
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On Sun, Aug 28, 2022 at 9:49 PM John Hubbard <jhubbard@nvidia.com> wrote:
>
> ...here. I count ~1000 calls to panic() in today's kernel, to a
> function in kernel/panic.c that shows no hint of being removed, nor
> even deprecated.

Heh. I guess we never finished the panic() removal.

It's been decades, I suspect we ended up deciding that the bootup
failures might as well continue to panic.

Anyway, please don't use it. It's one of those things that should
never ever trigger, and mainly for something like "oops, I ran out of
memory during boot" etc.

Oh, I'm sure it's crept into other places too, but that doesn't make it ok.

                 Linus