Re: Current mainline git (24e700e291d52bd2) hangs when building e.g. perf

[Markus Trippelsdorf]

On 2017.09.08 at 12:39 +0200, Markus Trippelsdorf wrote:
> On 2017.09.08 at 12:35 +0200, Ingo Molnar wrote:
> > 
> > * Markus Trippelsdorf <markus@xxxxxxxxxxxxxxx> wrote:
> > 
> > > On 2017.09.08 at 11:16 +0200, Borislav Petkov wrote:
> > > > On Fri, Sep 08, 2017 at 10:05:36AM +0200, Borislav Petkov wrote:
> > > > > On Fri, Sep 08, 2017 at 08:26:44AM +0200, Thomas Gleixner wrote:
> > > > > > On Fri, 8 Sep 2017, Markus Trippelsdorf wrote:
> > > > > > 
> > > > > > CC+ Borislav. He might have access to such a beast
> > > > > 
> > > > > Can I have /proc/cpuinfo and dmesg pls, in order to see whether I have
> > > > > something similar?
> > > > > 
> > > > > Private mail's fine too.
> > > > 
> > > > So I don't have exactly your model - mine is model 2, stepping 3 but I see
> > > > something strange too, in dmesg:
> > > 
> > > I'm pretty sure the bug is in the merged 'x86-mm-for-linus' branch:
> > > Either Andy's "PCID optimized TLB flushing" (would be my guess) or
> > > 'encrypted memory' support by Tom Lendacky.
> > > 
> > > (Bisecting is hard, because sometimes I can compile stuff for over 15
> > > minutes without hitting the bug. At other times the machine locks up
> > > hard when starting X11 already.)
> > 
> > Do you have the 72c0098d92ce fix?
> 
> Yes. The bug still happens on the current git tree (which has the fix
> already):

The bug is definitely caused by Andy Lutomirski's PCID optimized TLB
flushing" patches. Tom is off the hook.

-- 
Markus