Date: Thu, 27 Oct 2016 21:19:51 +0200
From: Borislav Petkov <bp@alien8.de>
To: Bob Peterson <rpeterso@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
        Andy Lutomirski <luto@amacapital.net>,
        Andreas Gruenbacher <agruenba@redhat.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Andy Lutomirski <luto@kernel.org>, LKML <linux-kernel@vger.kernel.org>,
        Steven Whitehouse <swhiteho@redhat.com>,
        Mel Gorman <mgorman@techsingularity.net>,
        linux-mm <linux-mm@kvack.org>
Subject: Re: CONFIG_VMAP_STACK, on-stack struct, and wake_up_bit
Message-ID: <20161027191951.zgcrcmvmla7ayeon@pd.tnic>
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On Thu, Oct 27, 2016 at 02:51:30PM -0400, Bob Peterson wrote:
> I couldn't recreate that first boot failure, even using .config.old,
> and even after removing (rm -fR) my linux.git and untarring it from the
> original tarball, doing a make clean, etc.

Hmm, so it could also depend on the randomized offset as it is getting
generated anew each boot. So you could try to boot a couple of times
to see if the randomized offset is generated just right for the bug
condition to match.

I mean, it would be great if you try a couple times but even if you're
unsuccessful, that's fine too - the fix is obviously correct and I've
confirmed that it boots fine in my VM here.

> The output before and after your new patch are the same (except for the times):
> 
> # dmesg | grep -i microcode
> [    5.291679] microcode: microcode updated early to new patch_level=0x010000d9

That looks good.

Thanks!

-- 
Regards/Gruss,
    Boris.

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