Date: Sat, 9 Sep 2017 20:29:52 +0200
From: Borislav Petkov <bp@alien8.de>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Markus Trippelsdorf <markus@trippelsdorf.de>,
        Andy Lutomirski <luto@kernel.org>, Ingo Molnar <mingo@kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Peter Zijlstra <peterz@infradead.org>,
        LKML <linux-kernel@vger.kernel.org>, Ingo Molnar <mingo@redhat.com>,
        Tom Lendacky <thomas.lendacky@amd.com>
Subject: Re: Current mainline git (24e700e291d52bd2) hangs when building e.g.
 perf
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On Sat, Sep 09, 2017 at 11:26:27AM -0700, Linus Torvalds wrote:
> But the fact that that fixes it for you does indicate that it's not
> just a stale TLB entry or something, it really is some CPU using page
> tables after they have been free'd and been re-allocated to something
> else (and *then* they may point to garbage).

Cool, I was trying to think of a good use case how we'd hit that. I
guess you just gave one. :)

Thx.

-- 
Regards/Gruss,
    Boris.

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