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Date:   Mon, 28 Sep 2020 10:54:01 +0200
From:   Borislav Petkov <bp@alien8.de>
To:     Dmitry Vyukov <dvyukov@google.com>
Cc:     Alexander Potapenko <glider@google.com>,
        Marco Elver <elver@google.com>,
        syzbot <syzbot+ce179bc99e64377c24bc@syzkaller.appspotmail.com>,
        Arnaldo Carvalho de Melo <acme@kernel.org>,
        Alexander Shishkin <alexander.shishkin@linux.intel.com>,
        "H. Peter Anvin" <hpa@zytor.com>, Jiri Olsa <jolsa@redhat.com>,
        LKML <linux-kernel@vger.kernel.org>,
        Mark Rutland <mark.rutland@arm.com>,
        Ingo Molnar <mingo@redhat.com>,
        Namhyung Kim <namhyung@kernel.org>,
        Peter Zijlstra <peterz@infradead.org>,
        syzkaller-bugs <syzkaller-bugs@googlegroups.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        the arch/x86 maintainers <x86@kernel.org>,
        clang-built-linux <clang-built-linux@googlegroups.com>
Subject: Re: general protection fault in perf_misc_flags
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On Mon, Sep 28, 2020 at 10:40:19AM +0200, Dmitry Vyukov wrote:
> I meant the kernel self-corrupts itself, that just wasn't detected by
> KASAN, page protections, etc.

Well, Nick already asked this but we're marking all kernel text RO early
during boot. So it either is happening before that or something else
altogether is going on.

And if that is a kernel issue, I believe we should've heard by now from
others. Or maybe this happens only in VMs.

Questions over questions...

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette