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From:   Linus Torvalds <torvalds@linux-foundation.org>
Date:   Tue, 21 Apr 2020 14:30:06 -0700
Message-ID: <CAHk-=whhpFhUV51jabGEzHN51aKTL5fbQBvNw9=3cXnO8PXs3A@mail.gmail.com>
Subject: Re: [BISECTED]: Kernel panic (was: Linux 5.7-rc2)
To:     Peter Zijlstra <peterz@infradead.org>
Cc:     Harald Arnesen <harald@skogtun.org>,
        Ingo Molnar <mingo@kernel.org>,
        "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Giovanni Gherdovich <ggherdovich@suse.cz>
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On Tue, Apr 21, 2020 at 2:23 PM Peter Zijlstra <peterz@infradead.org> wrote:
>
> (not seeing the original report in the archives or my list copy)

Hmm. It was cc'd to lkml, but maybe the attached 3.2MB picture ended
up making it too big to actually make it to the list...

The picture was just the bottom of the oops - I decoded the Code:
section just to verify that yeah, it's the div instruction in
arch_scale_freq_tick, from kernel_init -> native_smp_prepapre_cpus
(the rest of the oops has scrolled off the page).

> I'm assuming it's some sort of dodgy virt setup, actual real proper
> hardware should never get here like that.

It actually looks like a native boot on a Lenovo T510i laptop to me.

Also, see

  https://lore.kernel.org/lkml/b90ba443-9b9d-481e-7ecc-d5a25816e02f@oracle.com/

where Dave Kleikamp seems to say that it happens on his Lenovo T410.

So I do think it's real, and _not_ virtualization. Please don't
dismiss it as some vmware artifact. Looks more like it's triggered by
some Lenovo Thinkpad BIOS setup issue.

                Linus